Pathophysiology of ckd , bilateral small kidney with grade 2 rpc

Reading File

Finding Sources

Searching PubMed

"chronic kidney disease" AND "pathophysiology" AND "small kidney"

Finding Sources

Searching PubMed

"chronic kidney disease" AND pathophysiology

Finding Sources

Reading File

Finding Sources

Searching the Web

bilateral small kidneys grade 2 RPC renal parenchymal changes CKD ultrasound pathophysiology

Reading File

Reading Web Page

https://radiologykey.com/diffuse-renal-parenchymal-diseases

I now have comprehensive material to write a detailed answer. Let me compile the full response:

Pathophysiology of CKD with Bilateral Small Kidneys and Grade 2 Renal Parenchymal Changes (RPC)

What Does the Ultrasound Finding Mean?

Bilateral small kidneys with grade 2 RPC is a classic ultrasound constellation pointing to established chronic kidney disease (CKD). Here is how the grading works sonographically:

Grade	Echogenicity	Corticomedullary Differentiation	Size
Grade 0 (Normal)	Equal to or less than liver/spleen	Preserved	Normal (9-14 cm)
Grade 1	Mildly increased	Slightly reduced	Normal or mildly reduced
Grade 2	Moderately increased (equal to liver)	Reduced/indistinct	Reduced
Grade 3	Markedly increased (greater than liver)	Lost	Small/shrunken

At Grade 2, the parenchyma is echogenic (equal to liver echogenicity), corticomedullary differentiation is reduced, and the kidneys are smaller than normal - this reflects widespread cortical fibrosis, tubular atrophy, and nephron loss. The finding of small kidneys confirms a chronic process, because acute disease typically causes renal enlargement (edema) while chronic fibrosis causes contraction.

Normal renal size: 10-14 cm in males, 9-13 cm in females. Small kidneys = chronic diffuse disease.

Core Pathophysiology of CKD: The Common Pathway

Regardless of the initial cause (diabetic nephropathy, hypertension, glomerulonephritis, etc.), CKD progression follows a final common pathway first articulated by Brenner and colleagues. Understanding this is key to interpreting why kidneys become small and show parenchymal changes.

1. Intact Nephron Hypothesis (Bricker)

When nephrons are destroyed, the surviving nephrons undergo compensatory hypertrophy and hyperfiltration to maintain total GFR. Kidney function is supported by a diminishing pool of hyperfunctioning nephrons rather than by constant numbers of nephrons with reduced function. This glomerulotubular balance is preserved until the terminal stages of CKD.

Brenner and Rector's The Kidney - p. 1742

2. Glomerular Hemodynamic Adaptations (The Brenner Hypothesis)

Following nephron loss, remaining glomeruli undergo:

Afferent arteriolar vasodilation - increases blood flow to remaining glomeruli
Efferent arteriolar constriction - raises intraglomerular hydraulic pressure
Resulting single-nephron GFR (SNGFR) elevation - compensatory hyperfiltration

In experimental models (5/6 nephrectomy rats), the remnant kidney achieves a 300% increase in single-nephron GFR within 16 days. This is initially protective but becomes the engine of progressive injury.

Glomerular capillary hypertension (elevated Pgc) rather than hyperfiltration per se is the primary hemodynamic driver of injury. This causes:

Stretching and injury to glomerular capillary walls
Podocyte foot process effacement and loss
Mesangial cell activation
Proteinuria (due to disrupted filtration barrier)

Evidence: Both RAAS inhibitors and SGLT2 inhibitors reduce intraglomerular pressure and slow CKD progression - a strong mechanistic confirmation.

Brenner and Rector's The Kidney - p. 1743

3. Proteinuria as a Mediator of Tubular Injury

Filtered proteins (albumin, transferrin, complement factors) that reach the tubular lumen:

Are reabsorbed by proximal tubular cells, triggering inflammation and oxidative stress
Activate NF-kB and upregulate inflammatory cytokines (MCP-1, RANTES, osteopontin)
Stimulate tubular cell apoptosis and interstitial fibrosis
Drive recruitment of macrophages and monocytes into the interstitium

This is the link between glomerular damage and tubulointerstitial fibrosis - the histopathological hallmark most closely correlated with GFR decline.

4. Tubulointerstitial Fibrosis (TIF)

TIF is the final common endpoint regardless of initial disease. Key mechanisms include:

Epithelial-mesenchymal transition (EMT): Tubular epithelial cells transform into myofibroblasts, secreting collagen I, III, and IV
TGF-beta 1: The master pro-fibrotic cytokine, activates myofibroblasts and suppresses matrix metalloproteinases (reduces extracellular matrix degradation)
RAAS activation: Angiotensin II is independently pro-fibrotic beyond its hemodynamic effects; it directly stimulates TGF-beta production
Complement activation: C3a and C5a activate interstitial macrophages
Peritubular capillary rarefaction: Loss of peritubular capillaries causes tubular ischemia, further driving atrophy

The fibrotic interstitium compresses tubules, obstructs blood flow, and forces nephron dropout.

5. Glomerulosclerosis

Chronic intraglomerular hypertension causes:

Mesangial expansion - mesangial cells proliferate and deposit matrix
Podocyte loss - podocytes cannot regenerate; their loss leads to glomerular tuft collapse
Focal and segmental glomerulosclerosis (FSGS) morphology is the final common histological pattern, even when the primary disease was something else (e.g., IgA nephropathy, diabetic nephropathy)
Each sclerosed glomerulus = permanent nephron loss, feeding back into the cycle

6. The Vicious Cycle

Initial nephron loss
       ↓
Compensatory hyperfiltration + glomerular hypertension
       ↓
Podocyte injury → Proteinuria
       ↓
Tubular protein overload → Inflammation + TIF
       ↓
Peritubular capillary loss → Tubular ischemia
       ↓
Glomerulosclerosis → Further nephron loss
       ↓
(cycle repeats, accelerating)

Goldman-Cecil Medicine - p. 1346

7. Non-Hemodynamic Amplifying Mechanisms

Factor	Mechanism
Oxidative stress	Excess ROS from hypoxic tubules activates NF-kB, drives TGF-beta, damages DNA
Metabolic acidosis	Increases ammonia production (which activates complement), upregulates ET-1, accelerates fibrosis
Hypertension (systemic)	Incompletely buffered by autoregulation in damaged kidneys; transmitted to glomeruli
Anemia	Tubulointerstitial hypoxia from loss of EPO-producing cortical cells; further capillary dropout
Hyperphosphatemia	Vascular calcification, FGF-23 elevation (cardiotoxic), secondary hyperparathyroidism
Hyperuricemia	Activates NLRP3 inflammasome, induces arteriolopathy in afferent arterioles
Lipid accumulation	Lipotoxicity in proximal tubule cells; foam cell formation in interstitium
Superimposed AKI episodes	Each episode accelerates nephron loss beyond what recovers

Why Kidneys Become Small (Bilateral Renal Atrophy)

The reduction in kidney size reflects the end result of all the above processes:

Glomerulosclerosis - sclerosed glomeruli are replaced by hyaline, reducing renal mass
Tubular atrophy - loss of tubular cells, replacement by fibrous tissue
Interstitial fibrosis - fibrotic matrix contracts the kidney
Peritubular capillary rarefaction - vascular rarefaction with additional parenchymal loss
Compensatory sinus lipomatosis - expansion of renal sinus fat fills in the space left by atrophic parenchyma (a radiological clue)

Smooth contour of small kidneys (as seen here) implies diffuse, symmetric atrophy from chronic glomerulonephritis, hypertensive nephropathy, or diabetic nephropathy - as opposed to irregular/scarred contours from reflux nephropathy or infarctions.

Ultrasound Findings Explained by Pathology

Ultrasound Feature	Pathological Correlate
Increased echogenicity (Grade 2 = liver echogenicity)	Fibrosis replacing normal parenchyma; loss of normal medullary pyramids
Reduced corticomedullary differentiation	Cortical fibrosis making cortex as echogenic as medulla
Small kidney size	Nephron dropout, glomerulosclerosis, tubular atrophy
Smooth contour	Diffuse atrophy (not focal scarring) - suggests DM/HT/GN
Renal sinus fat prominence	Compensatory lipomatosis from parenchymal volume loss

Clinical Correlation: Grade 2 RPC + Small Kidneys

This pattern is typically associated with:

Diabetic nephropathy (most common cause globally; initially large kidneys that shrink late)
Hypertensive nephrosclerosis (arteriolosclerosis of afferent arterioles)
Chronic glomerulonephritis (IgA nephropathy, FSGS in end-stage)
Chronic interstitial nephritis (analgesic nephropathy, aristolochic acid, etc.)

The combination of bilateral small kidneys + Grade 2 RPC indicates CKD stage 3 or beyond in most patients, with significant irreversible parenchymal damage. It argues against a biopsy (risk of bleeding, low diagnostic yield from a shrunken fibrotic kidney) and toward management of CKD progression.

Key Management Implications from Pathophysiology

Since glomerular capillary hypertension drives the common pathway:

RAAS inhibitors (ACEi/ARB) - reduce efferent arteriolar tone, lower Pgc, reduce proteinuria, independently anti-fibrotic
SGLT2 inhibitors - restore tubuloglomerular feedback via macula densa (reduce afferent arteriolar tone), reduce intraglomerular pressure, have direct anti-inflammatory and anti-fibrotic renal effects - recent evidence (PMID 40196891) confirms cardiovascular-renal benefit
Blood pressure control - target <130/80 mmHg in CKD
Protein restriction - reduces proteinuria and metabolic acid load
Treat superimposed AKI promptly - each episode accelerates irreversible nephron loss
Correct acidosis - sodium bicarbonate supplementation shown to slow CKD progression

Sources:

Brenner and Rector's The Kidney, 2-Volume Set - Chapters 51, 31 (pp. 1742-1788)
Goldman-Cecil Medicine - p. 1346
AKI-to-CKD transition review 2024 (PMID 39298548)
Cardiovascular disease in CKD, Eur Heart J 2025 (PMID 40196891)
Grainger & Allison's Diagnostic Radiology - Diffuse Renal Parenchymal Diseases chapter

Make a presentation on CKD pathophysiology and renoprotective strategies

Reading File

Running Command

mkdir -p /tmp/workspace/ckd-presentation

Writing File

~/ckd-presentation/create_ckd_pptx.py

from pptx import Presentation
from pptx.util import Inches, Pt, Emu
from pptx.dml.color import RGBColor
from pptx.enum.text import PP_ALIGN, MSO_ANCHOR
from pptx.oxml.ns import qn
from lxml import etree
from io import BytesIO

# ── Palette ───────────────────────────────────────────────
NAVY      = RGBColor(0x0D, 0x2B, 0x55)   # dark navy
TEAL      = RGBColor(0x00, 0x84, 0x8A)   # accent teal
ORANGE    = RGBColor(0xE8, 0x6A, 0x1B)   # warm accent
LIGHT_BG  = RGBColor(0xF2, 0xF6, 0xFA)   # very light blue-grey
WHITE     = RGBColor(0xFF, 0xFF, 0xFF)
MID_GREY  = RGBColor(0x55, 0x65, 0x78)
LIGHT_TEAL= RGBColor(0xE0, 0xF4, 0xF5)
LIGHT_ORG = RGBColor(0xFD, 0xF0, 0xE6)
DARK_TEXT = RGBColor(0x1A, 0x1A, 0x2E)
RED_WARN  = RGBColor(0xC0, 0x39, 0x2B)

def new_prs():
    prs = Presentation()
    prs.slide_width  = Inches(13.333)
    prs.slide_height = Inches(7.5)
    return prs

def blank_slide(prs):
    return prs.slides.add_slide(prs.slide_layouts[6])

def fill_shape(shape, rgb):
    sp = shape._element
    spPr = sp.find(qn('p:spPr'))
    if spPr is None:
        spPr = etree.SubElement(sp, qn('p:spPr'))
    solidFill = etree.SubElement(spPr, qn('a:solidFill'))
    srgbClr   = etree.SubElement(solidFill, qn('a:srgbClr'))
    srgbClr.set('val', f'{rgb[0]:02X}{rgb[1]:02X}{rgb[2]:02X}')

def add_rect(slide, x, y, w, h, rgb):
    shape = slide.shapes.add_shape(1, Inches(x), Inches(y), Inches(w), Inches(h))
    shape.line.fill.background()
    fill_shape(shape, rgb)
    return shape

def add_textbox(slide, x, y, w, h, text, size, bold=False, color=DARK_TEXT,
                align=PP_ALIGN.LEFT, wrap=True, italic=False, font="Calibri"):
    tb = slide.shapes.add_textbox(Inches(x), Inches(y), Inches(w), Inches(h))
    tf = tb.text_frame
    tf.word_wrap = wrap
    tf.margin_left = 0; tf.margin_right = 0
    tf.margin_top = 0;  tf.margin_bottom = 0
    p = tf.paragraphs[0]
    p.alignment = align
    run = p.add_run()
    run.text = text
    run.font.name = font
    run.font.size = Pt(size)
    run.font.bold = bold
    run.font.italic = italic
    run.font.color.rgb = color
    return tf

def add_para(tf, text, size, bold=False, color=DARK_TEXT,
             align=PP_ALIGN.LEFT, italic=False, space_before=0, font="Calibri"):
    p = tf.add_paragraph()
    p.alignment = align
    if space_before:
        p.space_before = Pt(space_before)
    run = p.add_run()
    run.text = text
    run.font.name = font
    run.font.size = Pt(size)
    run.font.bold = bold
    run.font.italic = italic
    run.font.color.rgb = color
    return p

def add_bullet(tf, text, size=14, color=DARK_TEXT, indent=0, bold=False):
    p = tf.add_paragraph()
    p.level = indent
    run = p.add_run()
    bullet = "• " if indent == 0 else "  – "
    run.text = bullet + text
    run.font.name = "Calibri"
    run.font.size = Pt(size)
    run.font.bold = bold
    run.font.color.rgb = color

def slide_header(slide, title, subtitle=None):
    """Navy top bar with white title"""
    add_rect(slide, 0, 0, 13.333, 1.1, NAVY)
    add_textbox(slide, 0.4, 0.12, 12, 0.6, title,
                size=26, bold=True, color=WHITE, align=PP_ALIGN.LEFT)
    if subtitle:
        add_textbox(slide, 0.4, 0.68, 12, 0.38, subtitle,
                    size=13, bold=False, color=RGBColor(0xB0,0xD0,0xE8),
                    align=PP_ALIGN.LEFT)

def teal_box(slide, x, y, w, h, title, bullets, title_size=14, bullet_size=12.5):
    add_rect(slide, x, y, w, 0.42, TEAL)
    add_textbox(slide, x+0.1, y+0.05, w-0.2, 0.35, title,
                size=title_size, bold=True, color=WHITE)
    tb = slide.shapes.add_textbox(Inches(x), Inches(y+0.42),
                                   Inches(w), Inches(h-0.42))
    tf = tb.text_frame
    tf.word_wrap = True
    tf.margin_left = Inches(0.1); tf.margin_right = Inches(0.05)
    tf.margin_top = Inches(0.05)
    for i, b in enumerate(bullets):
        if i == 0:
            p = tf.paragraphs[0]
        else:
            p = tf.add_paragraph()
        run = p.add_run()
        run.text = "• " + b
        run.font.name = "Calibri"
        run.font.size = Pt(bullet_size)
        run.font.color.rgb = DARK_TEXT

def orange_box(slide, x, y, w, h, title, bullets, title_size=14, bullet_size=12.5):
    add_rect(slide, x, y, w, 0.42, ORANGE)
    add_textbox(slide, x+0.1, y+0.05, w-0.2, 0.35, title,
                size=title_size, bold=True, color=WHITE)
    tb = slide.shapes.add_textbox(Inches(x), Inches(y+0.42),
                                   Inches(w), Inches(h-0.42))
    tf = tb.text_frame
    tf.word_wrap = True
    tf.margin_left = Inches(0.1); tf.margin_right = Inches(0.05)
    tf.margin_top = Inches(0.05)
    for i, b in enumerate(bullets):
        if i == 0:
            p = tf.paragraphs[0]
        else:
            p = tf.add_paragraph()
        run = p.add_run()
        run.text = "• " + b
        run.font.name = "Calibri"
        run.font.size = Pt(bullet_size)
        run.font.color.rgb = DARK_TEXT

# ═══════════════════════════════════════════════════════════
# Build presentation
# ═══════════════════════════════════════════════════════════
prs = new_prs()

# ── SLIDE 1: Title ─────────────────────────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, NAVY)

# Diagonal accent stripe
accent = slide.shapes.add_shape(1, Inches(8.5), Inches(0), Inches(5), Inches(7.5))
fill_shape(accent, TEAL)
accent.line.fill.background()
# Overlap with lighter shade
accent2 = slide.shapes.add_shape(1, Inches(9.5), Inches(0), Inches(3.833), Inches(7.5))
fill_shape(accent2, RGBColor(0x00,0x6A,0x70))
accent2.line.fill.background()

add_textbox(slide, 0.6, 1.4, 8.5, 0.8, "CHRONIC KIDNEY DISEASE",
            size=36, bold=True, color=TEAL, font="Calibri")
add_textbox(slide, 0.6, 2.1, 8.5, 1.1,
            "Pathophysiology & Renoprotective Strategies",
            size=28, bold=True, color=WHITE, font="Calibri")
add_textbox(slide, 0.6, 3.2, 8.0, 0.4,
            "From Nephron Loss to End-Stage Kidney Disease",
            size=15, bold=False, color=RGBColor(0xB0,0xD0,0xE8), italic=True)
add_textbox(slide, 0.6, 5.8, 8.0, 0.35,
            "Based on Brenner & Rector's The Kidney | Harrison's Principles of Internal Medicine",
            size=11, color=RGBColor(0x80,0xA0,0xC0))
add_textbox(slide, 0.6, 6.2, 8.0, 0.35,
            "Goldman-Cecil Medicine | Grainger & Allison's Diagnostic Radiology",
            size=11, color=RGBColor(0x80,0xA0,0xC0))

# ── SLIDE 2: Overview / Agenda ─────────────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Presentation Overview",
             "A structured journey through CKD mechanisms and management")

items = [
    ("1", "Definition & Epidemiology", "What is CKD? Global burden, staging (KDIGO G & A categories)"),
    ("2", "Intact Nephron Hypothesis", "Bricker's hypothesis: hyperfunctioning nephron pool"),
    ("3", "Glomerular Hemodynamics", "Brenner hypothesis: hyperfiltration & glomerular capillary HTN"),
    ("4", "Proteinuria & Tubular Injury", "Filtered proteins as mediators of tubulointerstitial damage"),
    ("5", "Fibrosis & Sclerosis", "TGF-β1, EMT, glomerulosclerosis – the final common endpoint"),
    ("6", "Amplifying Factors", "Oxidative stress, acidosis, anemia, hyperuricemia, lipotoxicity"),
    ("7", "Bilateral Small Kidneys", "Radiological-pathological correlates; RPC grading"),
    ("8", "Renoprotective Strategies", "RAAS, SGLT2i, Finerenone, Sparsentan, lifestyle"),
    ("9", "Summary", "Key take-home points and clinical pearls"),
]

cols = [(0.3, 6.3), (6.8, 6.3)]
for i, (num, title, desc) in enumerate(items):
    col = 0 if i < 5 else 1
    cx, cw = cols[col]
    row = i if col == 0 else i - 5
    y = 1.25 + row * 1.18

    add_rect(slide, cx, y, 0.5, 0.55, TEAL)
    add_textbox(slide, cx+0.05, y+0.06, 0.4, 0.45, num,
                size=18, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, cx+0.6, y, cw-0.65, 0.32, title,
                size=13, bold=True, color=NAVY)
    add_textbox(slide, cx+0.6, y+0.3, cw-0.65, 0.3, desc,
                size=10.5, color=MID_GREY)

# ── SLIDE 3: Definition & Epidemiology ────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "CKD: Definition & Epidemiology",
             "KDIGO 2012 criteria remain the global standard")

add_rect(slide, 0.3, 1.25, 6.0, 2.35, WHITE)
tf = add_textbox(slide, 0.5, 1.35, 5.6, 0.38, "KDIGO Definition of CKD",
                 size=14, bold=True, color=NAVY)
tb = slide.shapes.add_textbox(Inches(0.5), Inches(1.75), Inches(5.6), Inches(1.7))
tf2 = tb.text_frame; tf2.word_wrap = True
for b in [
    "Abnormalities of kidney structure OR function",
    "Present for > 3 months",
    "With implications for health",
    "Markers: GFR <60 mL/min/1.73m² OR albuminuria (ACR ≥30 mg/g)",
    "Structural markers: small kidneys, cysts, histological abnormalities",
]:
    p = tf2.add_paragraph() if b != "Abnormalities of kidney structure OR function" else tf2.paragraphs[0]
    run = p.add_run()
    run.text = "✓  " + b
    run.font.name = "Calibri"; run.font.size = Pt(12); run.font.color.rgb = DARK_TEXT

add_rect(slide, 0.3, 3.75, 6.0, 1.05, TEAL)
add_textbox(slide, 0.5, 3.82, 5.6, 0.38, "KDIGO GFR Categories (G1–G5)",
            size=13, bold=True, color=WHITE)
cats = [("G1", ">90"), ("G2", "60–89"), ("G3a", "45–59"), ("G3b", "30–44"), ("G4", "15–29"), ("G5", "<15")]
for j, (g, val) in enumerate(cats):
    x = 0.35 + j*1.0
    add_rect(slide, x, 4.2, 0.92, 0.5, NAVY if j == 5 else (TEAL if j >= 3 else RGBColor(0x1A,0x7A,0x80)))
    add_textbox(slide, x+0.03, 4.22, 0.88, 0.25, g, size=11, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, x+0.03, 4.46, 0.88, 0.22, val, size=9.5, color=WHITE, align=PP_ALIGN.CENTER)

add_rect(slide, 6.55, 1.25, 6.5, 5.1, WHITE)
add_textbox(slide, 6.7, 1.35, 6.1, 0.38, "Global Burden",
            size=14, bold=True, color=NAVY)
epi_data = [
    ("~850 million", "people affected worldwide", TEAL),
    ("~10%", "of the global adult population", ORANGE),
    ("2–3 million", "deaths/year from kidney failure", RED_WARN),
    ("Top 5", "cause of years of life lost globally", NAVY),
    ("DM & HTN", "account for 50–60% of all CKD cases", TEAL),
    ("ESKD", "~180,000 new cases/year in the USA", ORANGE),
]
for k, (stat, label, color) in enumerate(epi_data):
    y_pos = 1.85 + k*0.72
    add_rect(slide, 6.7, y_pos, 2.0, 0.5, color)
    add_textbox(slide, 6.75, y_pos+0.04, 1.9, 0.28, stat,
                size=15, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, 6.75, y_pos+0.3, 1.9, 0.18, label,
                size=9, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, 8.85, y_pos+0.05, 4.0, 0.4, label,
                size=12, color=DARK_TEXT)

# ── SLIDE 4: Intact Nephron Hypothesis ────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "The Intact Nephron Hypothesis (Bricker)",
             "Remaining nephrons hypertrophy and hyperfunction to compensate for lost nephrons")

add_rect(slide, 0.3, 1.25, 6.1, 5.75, WHITE)
add_textbox(slide, 0.5, 1.35, 5.7, 0.38, "Core Concept",
            size=14, bold=True, color=NAVY)
tb = slide.shapes.add_textbox(Inches(0.5), Inches(1.8), Inches(5.7), Inches(4.8))
tf = tb.text_frame; tf.word_wrap = True
for b in [
    "Kidney function is maintained by a diminishing pool of hyperfunctioning nephrons",
    "Rather than a constant number of nephrons with diminishing function",
    "Glomerulotubular balance preserved until terminal CKD",
    "GFR falls only when nephron loss is substantial (>75%)",
    "",
    "Once GFR falls below a critical threshold → relentless progression",
    "Rate of GFR decline is LINEAR and characteristic of the individual patient",
    "Not the disease → implies a final COMMON PATHWAY",
    "",
    "Adaptive hypertrophy is driven by:",
    "  – Increased tubular workload per remaining nephron",
    "  – Hormonal signals: angiotensin II, IGF-1, EGF",
    "  – Hemodynamic: increased single-nephron GFR (SNGFR)",
    "",
    "Initially protective → ultimately MALADAPTIVE",
]:
    if b == "Core Concept" or b == "":
        p = tf.add_paragraph()
        p.add_run().text = b
        continue
    p = tf.add_paragraph()
    run = p.add_run()
    run.text = b
    run.font.name = "Calibri"; run.font.size = Pt(12.5)
    run.font.color.rgb = DARK_TEXT
    if b.startswith("  –"):
        run.font.color.rgb = MID_GREY

add_rect(slide, 6.7, 1.25, 6.3, 5.75, LIGHT_TEAL)
add_textbox(slide, 6.9, 1.35, 5.9, 0.38, "Experimental Evidence",
            size=14, bold=True, color=NAVY)

# Diagram: boxes and arrows
boxes = [
    (7.1, 2.05, 5.7, 0.55, "Normal: 2 kidneys, ~2 million nephrons", NAVY, WHITE),
    (7.1, 2.85, 5.7, 0.55, "Nephron loss (disease / nephrectomy)", RED_WARN, WHITE),
    (7.1, 3.65, 5.7, 0.55, "Remaining nephrons: hypertrophy & ↑SNGFR", TEAL, WHITE),
    (7.1, 4.45, 5.7, 0.55, "GFR maintained (initially)", RGBColor(0x27,0xAE,0x60), WHITE),
    (7.1, 5.25, 5.7, 0.55, "Maladaptation → glomerulosclerosis, fibrosis", ORANGE, WHITE),
    (7.1, 6.05, 5.7, 0.55, "Progressive nephron loss → ESKD", RED_WARN, WHITE),
]
for bx, by, bw, bh, btext, bcol, tcol in boxes:
    add_rect(slide, bx, by, bw, bh, bcol)
    add_textbox(slide, bx+0.1, by+0.1, bw-0.2, bh-0.1, btext,
                size=12.5, bold=True, color=tcol, align=PP_ALIGN.CENTER)
    if by < 6.05:
        add_textbox(slide, 9.3, by+0.55, 0.5, 0.3, "▼",
                    size=14, bold=True, color=NAVY, align=PP_ALIGN.CENTER)

# ── SLIDE 5: Glomerular Hemodynamics ──────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Glomerular Hemodynamic Adaptations – The Brenner Hypothesis",
             "Glomerular capillary hypertension is the primary driver of progressive nephron injury")

# Left column
add_rect(slide, 0.3, 1.25, 6.0, 5.75, WHITE)
add_textbox(slide, 0.5, 1.35, 5.7, 0.38, "Mechanism of Glomerular Hypertension",
            size=13.5, bold=True, color=NAVY)
tb = slide.shapes.add_textbox(Inches(0.5), Inches(1.8), Inches(5.7), Inches(4.5))
tf = tb.text_frame; tf.word_wrap = True
bullets_hem = [
    "Nephron loss → compensatory afferent arteriolar DILATION",
    "Increased glomerular plasma flow rate (Qα ↑)",
    "Efferent arteriolar constriction (angiotensin II mediated)",
    "Net effect: ↑ intraglomerular hydraulic pressure (Pgc)",
    "↑ Pgc → glomerular capillary HYPERTENSION",
    "",
    "In 5/6 nephrectomy rat model:",
    "  – 300% ↑ in SNGFR at 16 days post-op",
    "  – Direct measurement: Pgc elevated by 15–20 mmHg",
    "",
    "It is CAPILLARY HYPERTENSION (not hyperfiltration per se)",
    "that drives injury – key distinction for therapy",
    "",
    "Evidence (strong):",
    "  – RAAS inhibitors ↓ Pgc → renoprotection",
    "  – SGLT2 inhibitors ↓ Pgc via TGF → renoprotection",
    "  – Both act by different mechanisms yet same endpoint",
]
for i, b in enumerate(bullets_hem):
    p = tf.paragraphs[0] if i == 0 else tf.add_paragraph()
    run = p.add_run()
    run.text = b
    run.font.name = "Calibri"
    run.font.size = Pt(12.5)
    run.font.color.rgb = MID_GREY if b.startswith("  –") or b == "" else (NAVY if "Evidence" in b or "RAAS" in b or "SGLT2" in b else DARK_TEXT)
    run.font.bold = ("CAPILLARY HYPERTENSION" in b or b.startswith("Evidence"))

# Right: diagram
add_rect(slide, 6.6, 1.25, 6.4, 5.75, LIGHT_TEAL)
add_textbox(slide, 6.8, 1.35, 6.0, 0.38, "Glomerular Hemodynamic Changes",
            size=13.5, bold=True, color=NAVY)

params = [
    ("Renal Blood Flow (RBF)", "↑ Initially", TEAL),
    ("Glomerular Plasma Flow (Qα)", "↑↑", TEAL),
    ("Afferent Arteriole Tone", "↓ (dilated)", TEAL),
    ("Efferent Arteriole Tone", "↑ (AngII)", ORANGE),
    ("Intraglomerular Pressure (Pgc)", "↑↑ KEY DRIVER", RED_WARN),
    ("Single-Nephron GFR (SNGFR)", "↑↑↑", TEAL),
    ("Total GFR (initially)", "Maintained", RGBColor(0x27,0xAE,0x60)),
    ("Ultrafiltration Coefficient (Kf)", "↓ Late", ORANGE),
]
for j, (param, val, col) in enumerate(params):
    y_pos = 1.85 + j*0.58
    add_rect(slide, 6.8, y_pos, 3.8, 0.45, WHITE)
    add_textbox(slide, 6.9, y_pos+0.06, 3.6, 0.35, param, size=11.5, color=DARK_TEXT)
    add_rect(slide, 10.7, y_pos, 2.1, 0.45, col)
    add_textbox(slide, 10.75, y_pos+0.06, 2.0, 0.35, val,
                size=11.5, bold=True, color=WHITE, align=PP_ALIGN.CENTER)

add_textbox(slide, 6.8, 6.5, 6.0, 0.45,
            "★  ACE inhibitor/ARB: ↑ efferent dilation → ↓ Pgc  |  SGLT2i: ↑ TGF → ↑ afferent tone → ↓ Pgc",
            size=11, bold=True, color=NAVY)

# ── SLIDE 6: Proteinuria & Tubular Injury ─────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Proteinuria as a Mediator of Tubular Injury",
             "Filtered proteins are not innocent bystanders – they are active mediators of CKD progression")

teal_box(slide, 0.3, 1.25, 4.1, 3.0, "How Proteinuria Causes Tubular Damage", [
    "Disrupted filtration barrier → protein enters tubular lumen",
    "Proximal tubule cells reabsorb excess protein via endocytosis",
    "Protein overload triggers oxidative stress (ROS generation)",
    "Activates NF-κB → pro-inflammatory cytokine cascade",
    "Upregulates MCP-1, RANTES, osteopontin, ET-1",
    "Recruits macrophages/monocytes to interstitium",
    "Tubular cell apoptosis & interstitial inflammation",
])

orange_box(slide, 0.3, 4.4, 4.1, 2.6, "Key Inflammatory Mediators", [
    "TGF-β1: activates myofibroblasts, drives collagen deposition",
    "MCP-1 (CCL2): macrophage chemoattractant",
    "PDGF: fibroblast proliferation",
    "Angiotensin II: local amplifier of TGF-β1 production",
    "ET-1: vasoconstriction + pro-fibrotic",
    "Complement (C3a, C5a): interstitial macrophage activation",
])

teal_box(slide, 4.7, 1.25, 4.0, 3.0, "Progression of Tubular Injury", [
    "Stage 1: Protein overload → tubular cell stress",
    "Stage 2: NF-κB activation, cytokine release",
    "Stage 3: Macrophage infiltration, fibroblast activation",
    "Stage 4: EMT – tubular cells become myofibroblasts",
    "Stage 5: Extracellular matrix deposition (collagen I, III, IV)",
    "Stage 6: Tubular atrophy, loss of function",
    "Stage 7: Peritubular capillary rarefaction → ischaemia",
])

orange_box(slide, 4.7, 4.4, 4.0, 2.6, "Clinical Implications", [
    "Proteinuria grade correlates with rate of GFR decline",
    "Reducing proteinuria is a validated surrogate endpoint",
    "Target: ACR <30 mg/g (ideally <10 mg/g)",
    "Each 50% proteinuria reduction = ~30% less risk of ESKD",
    "Combined RAAS blockade → additive proteinuria reduction",
])

add_rect(slide, 9.0, 1.25, 4.0, 5.75, LIGHT_TEAL)
add_textbox(slide, 9.15, 1.35, 3.7, 0.38, "Downstream Consequences",
            size=13.5, bold=True, color=NAVY)
conseqs = [
    ("Tubulointerstitial Fibrosis", "TGF-β1 → myofibroblast activation → collagen deposition", TEAL),
    ("Tubular Atrophy", "Cell death → tubular dropout → loss of concentrating ability", ORANGE),
    ("Capillary Rarefaction", "Loss of peritubular capillaries → chronic hypoxia", RED_WARN),
    ("Interstitial Inflammation", "Macrophage infiltration → perpetuation of injury cycle", NAVY),
    ("Glomerulosclerosis", "Retrograde pressure from scarred tubules → glomerular collapse", ORANGE),
]
for k, (title_c, desc_c, col) in enumerate(conseqs):
    y_pos = 1.85 + k * 0.96
    add_rect(slide, 9.15, y_pos, 0.4, 0.72, col)
    add_textbox(slide, 9.65, y_pos, 3.2, 0.32, title_c, size=12, bold=True, color=DARK_TEXT)
    add_textbox(slide, 9.65, y_pos+0.32, 3.2, 0.38, desc_c, size=10.5, color=MID_GREY)

# ── SLIDE 7: Fibrosis & Glomerulosclerosis ────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Tubulointerstitial Fibrosis & Glomerulosclerosis",
             "The final common histopathological endpoint of all causes of CKD")

# TIF section
add_rect(slide, 0.3, 1.25, 6.1, 2.7, WHITE)
add_textbox(slide, 0.5, 1.35, 5.7, 0.38, "Tubulointerstitial Fibrosis (TIF)",
            size=14, bold=True, color=NAVY)
tb = slide.shapes.add_textbox(Inches(0.5), Inches(1.8), Inches(5.7), Inches(2.0))
tf = tb.text_frame; tf.word_wrap = True
tif_bullets = [
    "Best histological predictor of GFR decline (stronger than glomerular changes)",
    "Key driver: TGF-β1 from injured tubular cells and macrophages",
    "EMT: tubular epithelial cells transdifferentiate into myofibroblasts",
    "Myofibroblasts secrete collagen I, III, IV → permanent matrix deposition",
    "HIF-1α (hypoxia-inducible factor) amplifies TGF-β1 in hypoxic tubules",
    "Net: interstitial volume expands, tubules compress, nephrons drop out",
]
for i, b in enumerate(tif_bullets):
    p = tf.paragraphs[0] if i == 0 else tf.add_paragraph()
    run = p.add_run()
    run.text = "• " + b
    run.font.name = "Calibri"; run.font.size = Pt(12)
    run.font.color.rgb = DARK_TEXT

# GS section
add_rect(slide, 0.3, 4.1, 6.1, 2.7, WHITE)
add_textbox(slide, 0.5, 4.2, 5.7, 0.38, "Glomerulosclerosis",
            size=14, bold=True, color=NAVY)
tb2 = slide.shapes.add_textbox(Inches(0.5), Inches(4.65), Inches(5.7), Inches(2.0))
tf2 = tb2.text_frame; tf2.word_wrap = True
gs_bullets = [
    "Podocyte loss: podocytes cannot regenerate; loss = permanent",
    "Denuded GBM → mesangial expansion into capillary loops",
    "FSGS morphology: final common pattern regardless of initial disease",
    "Segmental sclerosis → segmental → global glomerulosclerosis",
    "Tubular injury (above) feeds back: obstructed tubules → glomerular atrophy",
    "Each sclerosed glomerulus = permanent, irreversible nephron loss",
]
for i, b in enumerate(gs_bullets):
    p = tf2.paragraphs[0] if i == 0 else tf2.add_paragraph()
    run = p.add_run()
    run.text = "• " + b
    run.font.name = "Calibri"; run.font.size = Pt(12)
    run.font.color.rgb = DARK_TEXT

# Right: Vicious cycle
add_rect(slide, 6.7, 1.25, 6.3, 5.75, LIGHT_TEAL)
add_textbox(slide, 6.9, 1.35, 5.9, 0.38, "The Vicious Cycle of CKD Progression",
            size=13.5, bold=True, color=NAVY)

cycle_steps = [
    ("Initial Nephron Loss", NAVY),
    ("Compensatory Hyperfiltration\n+ Glomerular Hypertension", TEAL),
    ("Podocyte Injury\n→ Proteinuria", ORANGE),
    ("Tubular Protein Overload\n→ Inflammation + TIF", RED_WARN),
    ("Capillary Rarefaction\n→ Tubular Ischaemia", ORANGE),
    ("Glomerulosclerosis\n→ Further Nephron Loss", RED_WARN),
]
for k, (label, col) in enumerate(cycle_steps):
    y_pos = 1.85 + k * 0.78
    add_rect(slide, 7.0, y_pos, 5.7, 0.6, col)
    add_textbox(slide, 7.05, y_pos+0.05, 5.6, 0.52, label,
                size=12, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    if k < 5:
        add_textbox(slide, 9.5, y_pos+0.6, 0.7, 0.2, "▼",
                    size=13, bold=True, color=NAVY, align=PP_ALIGN.CENTER)

add_rect(slide, 7.0, 6.5, 5.7, 0.4, NAVY)
add_textbox(slide, 7.05, 6.52, 5.6, 0.35,
            "↩  Cycle repeats — accelerating with each iteration",
            size=12, bold=True, color=WHITE, align=PP_ALIGN.CENTER)

# ── SLIDE 8: Amplifying Factors ───────────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Non-Hemodynamic Amplifying Factors",
             "Multiple concurrent mechanisms accelerate nephron loss beyond hemodynamics alone")

factors = [
    ("Oxidative Stress", [
        "NADPH oxidase → ↑ ROS in ischaemic tubules",
        "ROS activates NF-κB → TGF-β1, MCP-1 upregulation",
        "Mitochondrial dysfunction in podocytes and tubular cells",
        "Therapeutic target: finerenone (MRA) reduces OS",
    ], TEAL),
    ("Metabolic Acidosis", [
        "↑ Ammonia production per nephron → complement activation",
        "ET-1 upregulation → vasoconstriction + fibrosis",
        "Accelerates tubular injury independent of GFR",
        "NaHCO₃ supplementation slows CKD progression",
    ], ORANGE),
    ("RAAS Overactivation", [
        "AngII: pro-fibrotic (TGF-β1 induction) beyond BP effects",
        "Aldosterone: tubular inflammation, podocyte toxicity",
        "Intrarenal RAAS amplified in CKD independently of systemic BP",
        "Finerenone: non-steroidal MRA; renal + CV benefits",
    ], NAVY),
    ("Hyperphosphatemia & FGF-23", [
        "Phosphate retention → secondary HPT → vascular calcification",
        "FGF-23 rises early in CKD → direct cardiotoxic effect on LV",
        "FGF-23 also suppresses 1α-hydroxylase → ↓ calcitriol",
        "Target: dietary phosphate restriction, binders",
    ], TEAL),
    ("Anemia of CKD", [
        "Loss of cortical EPO-producing cells → absolute EPO deficiency",
        "Chronic inflammation → functional iron deficiency (hepcidin ↑)",
        "Anaemia → ↓ O₂ delivery → tubular ischaemia → fibrosis",
        "ESA + IV iron correct anaemia; SGLT2i modestly raise Hb",
    ], ORANGE),
    ("Superimposed AKI Episodes", [
        "Each AKI episode accelerates irreversible nephron loss",
        "Incomplete tubular repair → maladaptive fibrosis",
        "AKI-to-CKD transition via HIF, TGF-β1, pericyte activation",
        "Prevent: avoid nephrotoxins, adequate hydration, prompt Rx",
    ], RED_WARN),
]

positions = [
    (0.3, 1.25), (4.55, 1.25), (8.8, 1.25),
    (0.3, 4.05), (4.55, 4.05), (8.8, 4.05),
]
for (x, y), (title_f, blist, col) in zip(positions, factors):
    teal_box(slide, x, y, 4.0, 2.65, title_f, blist, title_size=13, bullet_size=11.5) if col == TEAL else \
    orange_box(slide, x, y, 4.0, 2.65, title_f, blist, title_size=13, bullet_size=11.5) if col == ORANGE else \
    (lambda: (add_rect(slide, x, y, 4.0, 0.42, col),
              add_textbox(slide, x+0.1, y+0.05, 3.8, 0.35, title_f, size=13, bold=True, color=WHITE),
              [exec("""
tb = slide.shapes.add_textbox(Inches(x), Inches(y+0.42), Inches(4.0), Inches(2.23))
tf = tb.text_frame; tf.word_wrap = True
tf.margin_left = Inches(0.1); tf.margin_top = Inches(0.05)
""") for _ in [1]],
              [(tf.paragraphs[0] if i == 0 else tf.add_paragraph()).add_run().__setattr__('text', '• ' + b) or
               setattr((tf.paragraphs[0] if i == 0 else tf.paragraphs[-1]).runs[-1].font, 'size', Pt(11.5))
               for i, b in enumerate(blist)]))()

# Simpler approach for navy boxes
for (x, y), (title_f, blist, col) in zip(positions, factors):
    if col == NAVY:
        add_rect(slide, x, y, 4.0, 0.42, NAVY)
        add_textbox(slide, x+0.1, y+0.05, 3.8, 0.35, title_f, size=13, bold=True, color=WHITE)
        tb = slide.shapes.add_textbox(Inches(x), Inches(y+0.42), Inches(4.0), Inches(2.23))
        tf = tb.text_frame; tf.word_wrap = True
        tf.margin_left = Inches(0.1); tf.margin_top = Inches(0.05)
        for i, b in enumerate(blist):
            p = tf.paragraphs[0] if i == 0 else tf.add_paragraph()
            run = p.add_run(); run.text = "• " + b
            run.font.name = "Calibri"; run.font.size = Pt(11.5); run.font.color.rgb = DARK_TEXT

# ── SLIDE 9: Bilateral Small Kidneys & RPC ────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Bilateral Small Kidneys & Renal Parenchymal Changes (RPC)",
             "Radiological-pathological correlation in CKD")

add_rect(slide, 0.3, 1.25, 5.8, 5.75, WHITE)
add_textbox(slide, 0.5, 1.35, 5.4, 0.38, "RPC Grading on Ultrasound",
            size=14, bold=True, color=NAVY)

grades = [
    ("Grade 0\n(Normal)", "Echogenicity ≤ liver/spleen\nCorticomedullary differentiation preserved\nSize: 10–14 cm (M), 9–13 cm (F)", RGBColor(0x27,0xAE,0x60)),
    ("Grade 1\n(Mild)", "Mildly ↑ echogenicity\nSlightly reduced CMD\nSize: mildly reduced or normal", TEAL),
    ("Grade 2\n(Moderate)", "Echogenicity = liver (isoechoic)\nReduced/indistinct CMD\nSize: reduced (small kidneys)", ORANGE),
    ("Grade 3\n(Severe)", "Echogenicity > liver (hyperechoic)\nCMD lost\nSize: markedly small/shrunken", RED_WARN),
]
for j, (grade, desc, col) in enumerate(grades):
    y_pos = 1.85 + j * 1.22
    add_rect(slide, 0.4, y_pos, 1.5, 0.95, col)
    add_textbox(slide, 0.42, y_pos+0.15, 1.46, 0.72, grade,
                size=11, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, 2.0, y_pos+0.05, 4.0, 0.9, desc, size=11, color=DARK_TEXT)

add_rect(slide, 6.4, 1.25, 6.6, 5.75, LIGHT_TEAL)
add_textbox(slide, 6.6, 1.35, 6.2, 0.38, "Pathological Correlates",
            size=14, bold=True, color=NAVY)

correlates = [
    ("↑ Echogenicity", "Fibrosis replacing normal parenchyma;\nloss of normal medullary pyramids", TEAL),
    ("↓ Corticomedullary\nDifferentiation", "Cortical fibrosis raises cortex echogenicity\nto match medulla", ORANGE),
    ("Small Kidney Size", "Glomerulosclerosis + tubular atrophy +\ninterstitial fibrosis → parenchymal contraction", NAVY),
    ("Smooth Contour", "Diffuse atrophy (DM/HTN/GN) –\nnot focal scarring (reflux/infarct)", RGBColor(0x27,0xAE,0x60)),
    ("Sinus Fat Prominence", "Compensatory lipomatosis:\nparenchymal volume loss → fat fills space", TEAL),
]
for k, (sign, patho, col) in enumerate(correlates):
    y_pos = 1.85 + k * 0.98
    add_rect(slide, 6.6, y_pos, 2.2, 0.78, col)
    add_textbox(slide, 6.65, y_pos+0.12, 2.1, 0.62, sign,
                size=11, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_textbox(slide, 8.9, y_pos+0.05, 3.9, 0.7, patho, size=11.5, color=DARK_TEXT)

add_rect(slide, 0.3, 6.75, 12.7, 0.45, NAVY)
add_textbox(slide, 0.5, 6.8, 12.3, 0.35,
            "Grade 2 RPC + bilateral small kidneys → CKD G3+ | Significant irreversible damage | Biopsy often contraindicated",
            size=12, bold=True, color=WHITE, align=PP_ALIGN.CENTER)

# ── SLIDE 10: Renoprotective Strategies Overview ──────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Renoprotective Strategies – Overview",
             "Targeting the common pathway at multiple points for maximum benefit")

add_rect(slide, 0.3, 1.25, 12.7, 0.55, TEAL)
add_textbox(slide, 0.5, 1.3, 12.3, 0.45,
            "Core Principle: Block the common pathway at multiple points — single-agent therapy is insufficient",
            size=13.5, bold=True, color=WHITE, align=PP_ALIGN.CENTER)

therapies = [
    ("RAAS Inhibitors\n(ACEi / ARB)", [
        "↑ Efferent arteriole dilation → ↓ Pgc",
        "Reduce proteinuria (30–50%)",
        "Direct anti-fibrotic (↓ TGF-β1 via ↓ AngII)",
        "Target: SBP <130 mmHg; ACR <30 mg/g",
        "1st-line in all proteinuric CKD",
    ], NAVY),
    ("SGLT2 Inhibitors\n(Dapagliflozin, Empagliflozin)", [
        "Restore tubuloglomerular feedback via macula densa",
        "↑ Afferent arteriolar tone → ↓ Pgc",
        "Direct anti-inflammatory + anti-fibrotic renal effects",
        "DAPA-CKD: 39% ↓ ESKD risk (independent of DM)",
        "EMPA-KIDNEY: consistent benefit at low eGFR",
    ], TEAL),
    ("Non-Steroidal MRA\n(Finerenone)", [
        "Blocks aldosterone + cortisol receptor in kidney",
        "↓ Podocyte toxicity, ↓ tubular inflammation",
        "FIDELIO-DKD / FIGARO-DKD: ↓ CKD progression + CV events",
        "Add to RAAS inhibitor in DKD with residual proteinuria",
        "Less hyperkalaemia vs. spironolactone",
    ], ORANGE),
    ("BP Control", [
        "Target <130/80 mmHg in all CKD (KDIGO 2024)",
        "Every 10 mmHg ↓ SBP = ~15% ↓ ESKD risk",
        "Avoid hypotension (↓ renal perfusion → AKI)",
        "Use RAAS inhibitor as backbone agent",
        "CCB: add-on; diuretics for volume control",
    ], RGBColor(0x1A,0x60,0x90)),
    ("Dual Endothelin/\nAngII Antagonist (Sparsentan)", [
        "Blocks ET-A and AT1 receptors simultaneously",
        "DUPLEX trial: superior proteinuria reduction vs. irbesartan",
        "FDA approved for IgA nephropathy (2023)",
        "Ongoing trials in FSGS and other glomerulopathies",
        "Emerging as an add-on renoprotective strategy",
    ], RGBColor(0x6A,0x1B,0x9A)),
    ("GLP-1 Receptor Agonists\n(Semaglutide)", [
        "FLOW trial (2024): semaglutide ↓ kidney failure by 24%",
        "Anti-inflammatory, ↓ proteinuria, weight reduction",
        "Benefit partially independent of glycaemic control",
        "Particularly useful in obese/diabetic CKD",
        "Emerging as 4th pillar alongside RAAS/SGLT2i/MRA",
    ], RGBColor(0x00,0x7A,0x5E)),
]

positions2 = [
    (0.3, 2.0), (4.55, 2.0), (8.8, 2.0),
    (0.3, 4.65), (4.55, 4.65), (8.8, 4.65),
]
for (x, y), (title_t, blist, col) in zip(positions2, therapies):
    add_rect(slide, x, y, 4.0, 0.48, col)
    add_textbox(slide, x+0.1, y+0.06, 3.8, 0.4, title_t, size=12, bold=True, color=WHITE)
    tb = slide.shapes.add_textbox(Inches(x), Inches(y+0.48), Inches(4.0), Inches(2.0))
    tf = tb.text_frame; tf.word_wrap = True
    tf.margin_left = Inches(0.08); tf.margin_top = Inches(0.05)
    for i, b in enumerate(blist):
        p = tf.paragraphs[0] if i == 0 else tf.add_paragraph()
        run = p.add_run(); run.text = "• " + b
        run.font.name = "Calibri"; run.font.size = Pt(11)
        run.font.color.rgb = DARK_TEXT

# ── SLIDE 11: RAAS + SGLT2i Deep Dive ────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Deep Dive: RAAS Inhibitors & SGLT2 Inhibitors",
             "The two cornerstone agents for renoprotection with complementary mechanisms")

# RAAS side
add_rect(slide, 0.3, 1.25, 6.2, 5.95, WHITE)
add_rect(slide, 0.3, 1.25, 6.2, 0.42, NAVY)
add_textbox(slide, 0.5, 1.3, 5.8, 0.38, "RAAS Inhibitors (ACEi / ARB)",
            size=14, bold=True, color=WHITE)
tb = slide.shapes.add_textbox(Inches(0.5), Inches(1.72), Inches(5.8), Inches(5.0))
tf = tb.text_frame; tf.word_wrap = True
raas_content = [
    ("MECHANISM OF ACTION", True, NAVY),
    ("• ACEi: blocks AngI→AngII conversion; ↑ bradykinin", False, DARK_TEXT),
    ("• ARB: blocks AT1 receptor; no bradykinin effect", False, DARK_TEXT),
    ("• Both: ↑ efferent arteriole dilation → ↓ intraglomerular pressure (Pgc)", False, DARK_TEXT),
    ("• Independent anti-fibrotic via ↓ AngII-TGF-β1 axis", False, DARK_TEXT),
    ("• ↓ Proteinuria by 30–50%", False, DARK_TEXT),
    ("", False, DARK_TEXT),
    ("KEY TRIAL EVIDENCE", True, NAVY),
    ("• RENAAL (losartan in DKD): 16% ↓ ESKD risk", False, DARK_TEXT),
    ("• IDNT (irbesartan in DKD): 23% ↓ ESKD risk", False, DARK_TEXT),
    ("• REIN (ramipril in non-DM proteinuric CKD): ↓ GFR slope", False, DARK_TEXT),
    ("", False, DARK_TEXT),
    ("PRACTICAL POINTS", True, NAVY),
    ("• Monitor K⁺ and creatinine after initiation (esp. bilateral RAS)", False, DARK_TEXT),
    ("• Acceptable: Cr rise ≤30% in first 2 months → continue", False, DARK_TEXT),
    ("• Avoid dual blockade (ACEi + ARB) — ↑ AKI + hyperkalaemia", False, DARK_TEXT),
    ("• Do NOT stop in CKD — reduction in Pgc is the desired effect", False, DARK_TEXT),
    ("• Adjust dose if GFR <30; hold during AKI/procedures", False, DARK_TEXT),
]
for i, (text, bold, col) in enumerate(raas_content):
    p = tf.paragraphs[0] if i == 0 else tf.add_paragraph()
    run = p.add_run(); run.text = text
    run.font.name = "Calibri"; run.font.size = Pt(12.5)
    run.font.bold = bold; run.font.color.rgb = col

# SGLT2i side
add_rect(slide, 6.8, 1.25, 6.2, 5.95, LIGHT_TEAL)
add_rect(slide, 6.8, 1.25, 6.2, 0.42, TEAL)
add_textbox(slide, 7.0, 1.3, 5.8, 0.38, "SGLT2 Inhibitors",
            size=14, bold=True, color=WHITE)
tb2 = slide.shapes.add_textbox(Inches(7.0), Inches(1.72), Inches(5.8), Inches(5.0))
tf2 = tb2.text_frame; tf2.word_wrap = True
sglt2_content = [
    ("MECHANISM OF ACTION", True, NAVY),
    ("• Inhibit SGLT2 co-transporter in proximal tubule S1 segment", False, DARK_TEXT),
    ("• ↑ Tubular NaCl delivery to macula densa → TGF activation", False, DARK_TEXT),
    ("• TGF → afferent arteriolar vasoconstriction → ↓ Pgc", False, DARK_TEXT),
    ("• Direct anti-inflammatory: ↓ NF-κB, ↓ NLRP3 inflammasome", False, DARK_TEXT),
    ("• Anti-fibrotic: ↓ TGF-β1, ↓ EMT in tubular cells", False, DARK_TEXT),
    ("• Mild osmotic diuresis → ↓ preload, ↓ tubular O₂ demand", False, DARK_TEXT),
    ("• Modest haematocrit ↑ → ↑ renal O₂ delivery", False, DARK_TEXT),
    ("", False, DARK_TEXT),
    ("KEY TRIAL EVIDENCE", True, NAVY),
    ("• CREDENCE (canagliflozin, DKD): 30% ↓ ESKD", False, DARK_TEXT),
    ("• DAPA-CKD (dapagliflozin): 39% ↓ ESKD — even non-DM", False, DARK_TEXT),
    ("• EMPA-KIDNEY (empagliflozin): benefit to eGFR ≥20", False, DARK_TEXT),
    ("", False, DARK_TEXT),
    ("PRACTICAL POINTS", True, NAVY),
    ("• No dose adjustment needed at low eGFR (non-glycaemic benefit)", False, DARK_TEXT),
    ("• Risk of DKA (rare), genital mycotic infections", False, DARK_TEXT),
    ("• Hold perioperatively and during AKI ('sick day rules')", False, DARK_TEXT),
    ("• Add to ACEi/ARB for complementary Pgc reduction", False, DARK_TEXT),
]
for i, (text, bold, col) in enumerate(sglt2_content):
    p = tf2.paragraphs[0] if i == 0 else tf2.add_paragraph()
    run = p.add_run(); run.text = text
    run.font.name = "Calibri"; run.font.size = Pt(12.5)
    run.font.bold = bold; run.font.color.rgb = col

# ── SLIDE 12: Additional Strategies ──────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, LIGHT_BG)
slide_header(slide, "Additional Renoprotective & Supportive Strategies",
             "Addressing complications and modifiable risk factors in CKD")

add_rect(slide, 0.3, 1.25, 4.0, 2.9, WHITE)
add_rect(slide, 0.3, 1.25, 4.0, 0.38, NAVY)
add_textbox(slide, 0.4, 1.28, 3.8, 0.32, "Glycaemic Control", size=13, bold=True, color=WHITE)
for b in ["HbA1c target 7–8% in DKD (avoid hypoglycaemia)","Metformin: safe to eGFR ≥30, suspend if <30","SGLT2i: primary choice (dual glycaemic + renal)","GLP-1 RA: secondary benefit (FLOW trial 2024)","Avoid sulphonylureas at low eGFR (hypo risk)"]:
    tb = slide.shapes.add_textbox(Inches(0.4), Inches(1.65 + ["HbA1c target 7–8% in DKD (avoid hypoglycaemia)","Metformin: safe to eGFR ≥30, suspend if <30","SGLT2i: primary choice (dual glycaemic + renal)","GLP-1 RA: secondary benefit (FLOW trial 2024)","Avoid sulphonylureas at low eGFR (hypo risk)"].index(b)*0.38), Inches(3.8), Inches(0.36))
    p = tb.text_frame.paragraphs[0]; run = p.add_run(); run.text = "• " + b
    run.font.name = "Calibri"; run.font.size = Pt(11.5); run.font.color.rgb = DARK_TEXT

add_rect(slide, 4.55, 1.25, 4.0, 2.9, WHITE)
add_rect(slide, 4.55, 1.25, 4.0, 0.38, TEAL)
add_textbox(slide, 4.65, 1.28, 3.8, 0.32, "Dietary & Lifestyle Measures", size=13, bold=True, color=WHITE)
for i, b in enumerate(["Protein: 0.8 g/kg/day in non-dialysis CKD","Low salt: <5 g/day (↓ BP, ↓ proteinuria)","Phosphate restriction in CKD G3b+","Potassium restriction when hyperkalaemia","Avoid NSAIDs, contrast nephropathy, nephrotoxins","Regular aerobic exercise improves BP and outcomes"]):
    tb = slide.shapes.add_textbox(Inches(4.65), Inches(1.65 + i*0.37), Inches(3.8), Inches(0.35))
    p = tb.text_frame.paragraphs[0]; run = p.add_run(); run.text = "• " + b
    run.font.name = "Calibri"; run.font.size = Pt(11.5); run.font.color.rgb = DARK_TEXT

add_rect(slide, 8.8, 1.25, 4.2, 2.9, WHITE)
add_rect(slide, 8.8, 1.25, 4.2, 0.38, ORANGE)
add_textbox(slide, 8.9, 1.28, 4.0, 0.32, "Managing CKD Complications", size=13, bold=True, color=WHITE)
for i, b in enumerate(["Anaemia: ESA when Hb <10 g/dL (target 10–11.5)","IV iron if ferritin <200 or TSAT <20%","Acidosis: NaHCO₃ if bicarbonate <22 mEq/L","Hyperphosphataemia: phosphate binders","Secondary HPT: active vitamin D (calcitriol)","Volume overload: loop diuretics, dietary salt/fluid Rx"]):
    tb = slide.shapes.add_textbox(Inches(8.9), Inches(1.65 + i*0.37), Inches(4.0), Inches(0.35))
    p = tb.text_frame.paragraphs[0]; run = p.add_run(); run.text = "• " + b
    run.font.name = "Calibri"; run.font.size = Pt(11.5); run.font.color.rgb = DARK_TEXT

add_rect(slide, 0.3, 4.3, 12.7, 2.9, WHITE)
add_rect(slide, 0.3, 4.3, 12.7, 0.38, NAVY)
add_textbox(slide, 0.5, 4.33, 12.3, 0.32, "KDIGO 2024: The Comprehensive Risk-Based Approach to CKD Management", size=13.5, bold=True, color=WHITE)

table_data = [
    ("GFR Category", "G1–G2 (≥60)", "G3a (45–59)", "G3b (30–44)", "G4 (15–29)", "G5 (<15 / dialysis)"),
    ("Monitoring (per yr)", "1–2x", "2–3x", "3–4x", "4–5x", "Monthly or per Rx"),
    ("RAAS Inhibitor", "Yes (if proteinuria)", "Yes (continue)", "Yes (continue)", "Yes (continue)", "Per specialist"),
    ("SGLT2 Inhibitor", "Yes (all)", "Yes", "Yes", "Benefit shown ≥20", "Not studied"),
    ("Dietitian referral", "If needed", "Recommended", "Required", "Required", "Required"),
]
col_widths = [2.0, 1.9, 1.9, 1.9, 1.9, 2.8]
col_x = [0.35]
for w in col_widths[:-1]:
    col_x.append(col_x[-1] + w + 0.08)
for row_i, row in enumerate(table_data):
    for col_i, cell in enumerate(row):
        x = col_x[col_i]; y = 4.72 + row_i * 0.42
        bg = LIGHT_TEAL if row_i == 0 else (LIGHT_BG if row_i % 2 == 0 else WHITE)
        add_rect(slide, x, y, col_widths[col_i], 0.4, bg)
        add_textbox(slide, x+0.05, y+0.06, col_widths[col_i]-0.1, 0.3, cell,
                    size=10.5, bold=(row_i == 0), color=NAVY if row_i == 0 else DARK_TEXT)

# ── SLIDE 13: Summary ─────────────────────────────────────
slide = blank_slide(prs)
add_rect(slide, 0, 0, 13.333, 7.5, NAVY)
add_rect(slide, 0, 0, 13.333, 1.1, TEAL)
add_textbox(slide, 0.5, 0.12, 12.3, 0.85, "Summary & Key Take-Home Points",
            size=26, bold=True, color=WHITE)

takeaways = [
    ("1", "Common Pathway", "Regardless of cause, CKD progresses through glomerular capillary hypertension → proteinuria → TIF → glomerulosclerosis. This cycle is self-perpetuating."),
    ("2", "Small Kidneys = Chronicity", "Bilateral small kidneys with Grade 2 RPC on USS indicate significant irreversible damage (CKD G3+). Smooth contour = diffuse disease (DM/HTN/GN)."),
    ("3", "RAAS First", "ACEi/ARB remain the cornerstone — they reduce intraglomerular pressure AND proteinuria AND fibrosis. Never stop unless truly contraindicated."),
    ("4", "Add SGLT2i", "Dapagliflozin/Empagliflozin provide complementary Pgc reduction via TGF, with direct anti-inflammatory and anti-fibrotic renal effects — benefit extends to non-diabetic CKD."),
    ("5", "Then Add Finerenone", "In diabetic CKD with residual proteinuria on RAAS blockade, finerenone (non-steroidal MRA) provides additive renal and cardiovascular benefit with acceptable K⁺ profile."),
    ("6", "Emerging 4th Pillar", "GLP-1 RA (semaglutide – FLOW 2024) show 24% kidney failure reduction. Sparsentan is FDA-approved for IgA nephropathy. The renoprotection toolkit is expanding."),
    ("7", "Treat the Whole Patient", "Address acidosis (NaHCO₃), anaemia (ESA/iron), hyperphosphataemia, BP control, and prevent AKI episodes — each is an independent contributor to CKD progression."),
]
for k, (num, title_s, body_s) in enumerate(takeaways):
    col = k % 2
    row = k // 2
    x = 0.3 if col == 0 else 6.85
    y = 1.25 + row * 1.38
    if k == 6:  # last item spans center
        x = 3.5; y = 1.25 + 3 * 1.38

    add_rect(slide, x, y, 0.6, 0.8, TEAL)
    add_textbox(slide, x+0.05, y+0.15, 0.5, 0.55, num, size=18, bold=True, color=WHITE, align=PP_ALIGN.CENTER)
    add_rect(slide, x+0.6, y, 5.7 if k < 6 else 6.3, 0.8, RGBColor(0x15,0x3A,0x6E))
    add_textbox(slide, x+0.7, y+0.04, 5.5 if k < 6 else 6.1, 0.28, title_s, size=12, bold=True, color=TEAL)
    add_textbox(slide, x+0.7, y+0.3, 5.5 if k < 6 else 6.1, 0.46, body_s, size=10.5, color=RGBColor(0xCC,0xDD,0xEE))

add_rect(slide, 0.3, 6.65, 12.7, 0.55, RGBColor(0x0A,0x1E,0x40))
add_textbox(slide, 0.5, 6.7, 12.3, 0.42,
            "Brenner & Rector's The Kidney  |  Harrison's Principles of Internal Medicine 22E  |  Goldman-Cecil Medicine  |  KDIGO Guidelines",
            size=10.5, color=RGBColor(0x80,0xA0,0xC0), align=PP_ALIGN.CENTER)

# ── SAVE ─────────────────────────────────────────────────
out = "/tmp/workspace/ckd-presentation/CKD_Pathophysiology_Renoprotection.pptx"
buf = BytesIO()
prs.save(buf)
with open(out, "wb") as f:
    f.write(buf.getvalue())
print(f"Saved: {out}")
print(f"Slides: {len(prs.slides)}")

Running Command

cd /tmp/workspace/ckd-presentation && python create_ckd_pptx.py 2>&1

Running Command

ls -lh /tmp/workspace/ckd-presentation/CKD_Pathophysiology_Renoprotection.pptx

Your presentation is ready. Download it here:

CKD Pathophysiology Renoprotection

Presentation · PPTX

13 slides in a professional navy/teal/orange color scheme, covering:

Slide	Content
1	Title slide
2	Presentation overview / agenda
3	CKD definition, KDIGO G-categories, epidemiology stats
4	Intact Nephron Hypothesis (Bricker) - with step-down flow diagram
5	Glomerular Hemodynamic Adaptations (Brenner Hypothesis) - Pgc table
6	Proteinuria as a mediator of tubular injury - 5-column pathway layout
7	Tubulointerstitial fibrosis, glomerulosclerosis & the vicious cycle
8	6 non-hemodynamic amplifying factors (oxidative stress, acidosis, RAAS, FGF-23, anemia, AKI)
9	Bilateral small kidneys - RPC grading table + pathological correlates
10	Renoprotective strategies overview (all 6 drug classes)
11	Deep dive: RAAS inhibitors vs. SGLT2 inhibitors - mechanisms + trial evidence
12	Additional strategies + KDIGO 2024 monitoring table by GFR category
13	Summary - 7 take-home points

Sources cited include Brenner & Rector's The Kidney, Harrison's 22E, Goldman-Cecil Medicine, and KDIGO guidelines.

This is a shared conversation. Sign in to Orris to start your own chat.