#!/usr/bin/env python3
"""
MD Medicine Final Exam Notes — PDF Generator
Topic: Approach to Dyspnea + Lung Abscess (Pathophysiology, DDx, Management)
"""

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import cm, mm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    HRFlowable, PageBreak, ListFlowable, ListItem
)
from reportlab.lib.enums import TA_LEFT, TA_CENTER, TA_JUSTIFY
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont

OUTPUT_PATH = "/home/daytona/workspace/md-medicine-notes/Dyspnea_LungAbscess_MDMedicine.pdf"

# ── Colour palette ─────────────────────────────────────────────────────────────
DARK_BLUE   = colors.HexColor("#1a3a5c")
MID_BLUE    = colors.HexColor("#2563a8")
LIGHT_BLUE  = colors.HexColor("#dbeafe")
ACCENT_RED  = colors.HexColor("#c0392b")
ACCENT_GRN  = colors.HexColor("#1a7a4a")
ACCENT_ORG  = colors.HexColor("#e67e22")
GREY_BG     = colors.HexColor("#f3f4f6")
GREY_LINE   = colors.HexColor("#d1d5db")
WHITE       = colors.white
BLACK       = colors.black

def make_doc():
    doc = SimpleDocTemplate(
        OUTPUT_PATH,
        pagesize=A4,
        rightMargin=2*cm, leftMargin=2*cm,
        topMargin=2.2*cm, bottomMargin=2.2*cm,
        title="MD Medicine: Dyspnea & Lung Abscess",
        author="Orris AI — Medical Study Notes"
    )
    styles = getSampleStyleSheet()

    # ── Custom styles ──────────────────────────────────────────────────────────
    h_title = ParagraphStyle("h_title", parent=styles["Title"],
        fontSize=22, textColor=DARK_BLUE, spaceAfter=4,
        fontName="Helvetica-Bold", alignment=TA_CENTER, leading=26)

    h_sub = ParagraphStyle("h_sub", parent=styles["Normal"],
        fontSize=11, textColor=MID_BLUE, spaceAfter=14,
        fontName="Helvetica", alignment=TA_CENTER, leading=14)

    h1 = ParagraphStyle("h1", parent=styles["Heading1"],
        fontSize=14, textColor=WHITE, spaceAfter=6, spaceBefore=14,
        fontName="Helvetica-Bold", leading=18,
        backColor=DARK_BLUE, borderPad=6,
        leftIndent=-8, rightIndent=-8)

    h2 = ParagraphStyle("h2", parent=styles["Heading2"],
        fontSize=12, textColor=DARK_BLUE, spaceAfter=4, spaceBefore=10,
        fontName="Helvetica-Bold", leading=16,
        borderPad=(0, 0, 2, 0))

    h3 = ParagraphStyle("h3", parent=styles["Heading3"],
        fontSize=11, textColor=MID_BLUE, spaceAfter=3, spaceBefore=6,
        fontName="Helvetica-BoldOblique", leading=14)

    body = ParagraphStyle("body", parent=styles["Normal"],
        fontSize=10, textColor=BLACK, spaceAfter=5,
        fontName="Helvetica", leading=14, alignment=TA_JUSTIFY)

    bullet = ParagraphStyle("bullet", parent=styles["Normal"],
        fontSize=10, textColor=BLACK, spaceAfter=3,
        fontName="Helvetica", leading=13, leftIndent=14,
        bulletIndent=4, alignment=TA_LEFT)

    note_style = ParagraphStyle("note", parent=styles["Normal"],
        fontSize=9.5, textColor=colors.HexColor("#374151"),
        backColor=LIGHT_BLUE, borderPad=6,
        leftIndent=6, rightIndent=6, spaceAfter=8,
        fontName="Helvetica-Oblique", leading=13)

    warn_style = ParagraphStyle("warn", parent=styles["Normal"],
        fontSize=9.5, textColor=colors.HexColor("#7f1d1d"),
        backColor=colors.HexColor("#fee2e2"), borderPad=6,
        leftIndent=6, rightIndent=6, spaceAfter=8,
        fontName="Helvetica-Bold", leading=13)

    tip_style = ParagraphStyle("tip", parent=styles["Normal"],
        fontSize=9.5, textColor=colors.HexColor("#14532d"),
        backColor=colors.HexColor("#dcfce7"), borderPad=6,
        leftIndent=6, rightIndent=6, spaceAfter=8,
        fontName="Helvetica", leading=13)

    ref_style = ParagraphStyle("ref", parent=styles["Normal"],
        fontSize=8.5, textColor=colors.HexColor("#6b7280"),
        fontName="Helvetica-Oblique", leading=12, spaceAfter=2)

    story = []

    # ══════════════════════════════════════════════════════════════════════════
    # COVER / HEADER
    # ══════════════════════════════════════════════════════════════════════════
    story.append(Spacer(1, 0.5*cm))
    story.append(Paragraph("MD MEDICINE — FINAL EXAMINATION NOTES", h_title))
    story.append(Paragraph(
        "Approach to Dyspnea  |  Lung Abscess: Pathophysiology, Differential Diagnosis & Management",
        h_sub))
    story.append(HRFlowable(width="100%", thickness=2, color=MID_BLUE, spaceAfter=10))
    story.append(Paragraph(
        "<i>Sources: Harrison's Principles of Internal Medicine 22e (2025) · Goldman-Cecil Medicine · "
        "Robbins &amp; Kumar Basic Pathology · Fishman's Pulmonary Diseases and Disorders · "
        "Murray &amp; Nadel's Textbook of Respiratory Medicine</i>",
        ref_style))
    story.append(Spacer(1, 0.3*cm))

    # ══════════════════════════════════════════════════════════════════════════
    # PART 1 — APPROACH TO DYSPNEA
    # ══════════════════════════════════════════════════════════════════════════
    story.append(Paragraph("PART 1 — APPROACH TO A CASE OF DYSPNEA", h1))
    story.append(Spacer(1, 0.2*cm))

    # 1.1 Definition
    story.append(Paragraph("1. Definition", h2))
    story.append(Paragraph(
        "Dyspnea is the sensation of difficult, labored, or <b>unpleasant breathing</b>. "
        "The qualifier 'unpleasant' is critical — labored breathing in a healthy person during exercise "
        "does NOT qualify as dyspnea because it is expected for the degree of exertion. "
        "The physiology of dyspnea remains incompletely understood; multiple afferent neural pathways are "
        "involved, including signals from pulmonary stretch receptors, peripheral/central chemoreceptors, "
        "respiratory muscles, and the cardiovascular system.",
        body))
    story.append(Spacer(1, 0.2*cm))

    # 1.2 Classification
    story.append(Paragraph("2. Classification (First Step in Every Case)", h2))
    story.append(Paragraph(
        "The <b>first clinical question</b> is: <i>Is this dyspnea acute or chronic?</i> "
        "This determines the urgency and differential.",
        body))

    class_data = [
        [Paragraph("<b>Feature</b>", bullet),
         Paragraph("<b>Acute Dyspnea</b>", bullet),
         Paragraph("<b>Chronic Dyspnea</b>", bullet)],
        [Paragraph("Onset", bullet),
         Paragraph("Sudden / minutes–hours", bullet),
         Paragraph("Weeks to months", bullet)],
        [Paragraph("Priority", bullet),
         Paragraph("Rule out life-threatening causes FIRST", bullet),
         Paragraph("Systematic workup for underlying disease", bullet)],
        [Paragraph("Key DDx", bullet),
         Paragraph("PE, pulmonary oedema, pneumothorax, anaphylaxis, pneumonia, acute airway obstruction", bullet),
         Paragraph("COPD, asthma, ILD, heart failure, cardiomyopathy, GERD, hyperventilation", bullet)],
    ]
    class_table = Table(class_data, colWidths=[3.5*cm, 7.5*cm, 7.5*cm])
    class_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("BACKGROUND", (0, 1), (-1, 1), LIGHT_BLUE),
        ("BACKGROUND", (0, 2), (-1, 2), GREY_BG),
        ("BACKGROUND", (0, 3), (-1, 3), LIGHT_BLUE),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.4, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(class_table)
    story.append(Spacer(1, 0.3*cm))

    # 1.3 History
    story.append(Paragraph("3. History Taking", h2))
    story.append(Paragraph("<b>A. Characterise the dyspnea:</b>", h3))
    history_items = [
        "Onset: sudden (pneumothorax, PE) vs. gradual (COPD, heart failure, ILD)",
        "Duration: acute (<72 h), subacute (days–weeks), chronic (>1 month)",
        "Severity: quantify — MRC dyspnoea scale (Grade 1–5), oxygen saturation",
        "Progression: stable, worsening, episodic (asthma, paroxysmal nocturnal dyspnoea)",
        "Precipitating factors: exertion, allergens, posture (orthopnoea → heart failure; platypnoea → AVM/cirrhosis)",
        "Relieving factors: bronchodilators (asthma/COPD), sitting upright (heart failure)",
        "Associated symptoms: cough, wheeze, haemoptysis, fever, chest pain, ankle swelling, palpitations",
        "Positional: orthopnoea, trepopnoea (unilateral lung/pleural disease)",
    ]
    for item in history_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    story.append(Paragraph("<b>B. Past medical history &amp; risk factors:</b>", h3))
    risk_items = [
        "Cardiac history: IHD, hypertension, rheumatic heart disease, arrhythmias",
        "Respiratory history: asthma, COPD, TB, recurrent respiratory infections",
        "Smoking history (pack-years) — essential for COPD, lung cancer",
        "Occupational history: asbestos → mesothelioma/asbestosis; silica → silicosis; birds → EAA",
        "Drug history: amiodarone (pulmonary toxicity), methotrexate (ILD), ACE inhibitors (cough-induced dyspnoea)",
        "Travel history: coccidioidomycosis, paragonimiasis, schistosomiasis",
        "Family history: alpha-1 antitrypsin deficiency, cystic fibrosis, pulmonary hypertension",
        "DVT/PE risk: immobility, surgery, OCP, malignancy, long travel",
    ]
    for item in risk_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    story.append(Paragraph('<b>"Red Flag" Symptoms — Must Not Be Missed</b>', h3))
    story.append(Paragraph(
        '<font color="#c0392b"><b>⚠ Haemoptysis · Prominent dyspnoea at rest or at night · '
        'Fever with productive cough · Hoarseness · Systemic symptoms (weight loss, night sweats) · '
        'Smoker &gt;45 years with new or changed cough · 30 pack-year history aged 55–80</b></font>',
        warn_style))

    # 1.4 Physical Examination
    story.append(Paragraph("4. Physical Examination", h2))
    pe_data = [
        [Paragraph("<b>System</b>", bullet), Paragraph("<b>Key Findings &amp; Interpretation</b>", bullet)],
        [Paragraph("General", bullet),
         Paragraph("Cyanosis (central vs. peripheral), clubbing (ILD, lung cancer, bronchiectasis, cyanotic CHD), "
                   "pallor (anaemia), cachexia (malignancy/COPD), use of accessory muscles, pursed-lip breathing", bullet)],
        [Paragraph("Vital Signs", bullet),
         Paragraph("RR >25/min → severe respiratory distress; SpO₂ on pulse oximetry; tachycardia; BP (pulsus paradoxus in asthma/tamponade)", bullet)],
        [Paragraph("Neck/JVP", bullet),
         Paragraph("Raised JVP → heart failure, cardiac tamponade, SVC obstruction, cor pulmonale; "
                   "tracheal deviation → pneumothorax (ipsilateral), collapse (contralateral)", bullet)],
        [Paragraph("Chest Inspection", bullet),
         Paragraph("Barrel chest (COPD); asymmetric expansion; Harrison sulcus; kyphoscoliosis", bullet)],
        [Paragraph("Percussion", bullet),
         Paragraph("Dullness → effusion, consolidation, collapse; Hyperresonance → pneumothorax, emphysema", bullet)],
        [Paragraph("Auscultation", bullet),
         Paragraph("Wheeze → asthma, COPD, cardiac asthma; Crepitations → pulmonary oedema (fine basal), "
                   "pneumonia, ILD; Amphoric/cavernous → lung abscess, cavity; Absent breath sounds → "
                   "effusion, pneumothorax; Bronchial breath sounds → consolidation", bullet)],
        [Paragraph("Cardiovascular", bullet),
         Paragraph("S3 gallop, displaced apex → heart failure; loud P2 → pulmonary hypertension; "
                   "murmurs → valvular disease; peripheral oedema", bullet)],
        [Paragraph("Abdomen", bullet),
         Paragraph("Hepatomegaly/ascites → cor pulmonale/right heart failure; hepatosplenomegaly → sarcoidosis", bullet)],
    ]
    pe_table = Table(pe_data, colWidths=[3.5*cm, 15*cm])
    pe_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG]),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(pe_table)
    story.append(Spacer(1, 0.3*cm))

    # 1.5 Investigations
    story.append(Paragraph("5. Investigations", h2))
    story.append(Paragraph("<b>A. First-Line (All Cases of Unexplained Dyspnoea):</b>", h3))
    inv1 = [
        "<b>Chest X-ray</b> — hyperinflation (COPD/asthma), cardiomegaly (heart failure), infiltrates (pneumonia/ILD), "
        "effusion, pneumothorax, cavitation (lung abscess/TB)",
        "<b>ECG</b> — arrhythmia, LV hypertrophy, right heart strain (PE pattern: S1Q3T3), ischaemia",
        "<b>Arterial Blood Gas (ABG)</b> — type 1 vs type 2 respiratory failure; A-a gradient (PE, ILD); "
        "pH for respiratory/metabolic acidosis",
        "<b>Pulse Oximetry</b> — SpO₂; note: may be falsely normal in anaemia or CO poisoning",
        "<b>Full Blood Count</b> — anaemia, leukocytosis (infection), eosinophilia (asthma/EAA/eosinophilic pneumonia)",
        "<b>Serum BNP/NT-proBNP</b> — <b>extremely helpful</b> in acute dyspnoea to distinguish heart failure from "
        "pulmonary causes (BNP >400 pg/mL → heart failure likely)",
        "<b>Renal/Liver Function, Electrolytes</b> — metabolic causes of dyspnoea, pulmonary-renal syndromes",
    ]
    for item in inv1:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>B. Second-Line (Guided by History and First-Line Results):</b>", h3))
    inv2 = [
        "<b>Pulmonary Function Tests (PFTs):</b> Spirometry (obstructive vs. restrictive); DLCO (ILD, emphysema, vascular disease); "
        "Flow-volume loops (upper airway obstruction); Methacholine challenge (asthma)",
        "<b>High-Resolution CT Chest (HRCT):</b> Gold standard for ILD; better delineation of cavities, mediastinum, "
        "pulmonary emboli (CTPA), bronchiectasis",
        "<b>Echocardiography:</b> LV/RV function, wall motion abnormalities, valvular disease, pulmonary hypertension, "
        "pericardial effusion — essential when heart failure suspected",
        "<b>CTPA / V/Q Scan:</b> Pulmonary embolism (Wells score guides pre-test probability); D-dimer as screening tool",
        "<b>Point-of-Care Ultrasound (POCUS):</b> Rapidly detects heart failure, pneumonia, PE, pleural effusion, "
        "pneumothorax at bedside — improves sensitivity of standard pathways",
        "<b>6-Minute Walk Test / Cardiopulmonary Exercise Testing (CPET):</b> Quantifies functional capacity; "
        "identifies exercise-induced desaturation and cardiac vs. pulmonary limitation",
        "<b>Bronchoscopy:</b> BAL, biopsy for ILD, endobronchial lesions, haemoptysis workup",
        "<b>Sputum analysis:</b> Gram stain, culture, AFB (TB), cytology (malignancy), eosinophils (EAA)",
        "<b>GERD evaluation:</b> 24-hr oesophageal pH monitoring / modified barium swallow when GERD suspected as cause",
    ]
    for item in inv2:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    story.append(Paragraph(
        "💡 Clinical Tip: BNP testing in acute dyspnoea and POCUS assessment by trained clinicians "
        "improve the sensitivity of standard diagnostic pathways to detect heart failure, pneumonia, PE, "
        "pleural effusion, and pneumothorax (Goldman-Cecil Medicine).",
        tip_style))

    # 1.6 Differential Diagnosis Table
    story.append(Paragraph("6. Differential Diagnosis of Dyspnea — System-Based Approach", h2))

    ddx_data = [
        [Paragraph("<b>System</b>", bullet),
         Paragraph("<b>Common Causes</b>", bullet),
         Paragraph("<b>Distinguishing Features</b>", bullet)],
        # Obstructive
        [Paragraph("<b>Obstructive Airway</b>", bullet),
         Paragraph("Asthma, COPD, bronchiectasis", bullet),
         Paragraph("Expiratory wheeze, prolonged expiratory phase, ↓FEV₁/FVC, reversibility (asthma)", bullet)],
        # Restrictive
        [Paragraph("<b>Restrictive / Parenchymal</b>", bullet),
         Paragraph("ILD, sarcoidosis, pulmonary fibrosis, pneumoconiosis", bullet),
         Paragraph("Bilateral fine crackles, clubbing, ↓TLC, ↓DLCO, HRCT abnormalities", bullet)],
        # Infection
        [Paragraph("<b>Infection</b>", bullet),
         Paragraph("Pneumonia, lung abscess, empyema, TB", bullet),
         Paragraph("Fever, productive cough, consolidation/cavity on CXR, leukocytosis", bullet)],
        # Vascular
        [Paragraph("<b>Vascular</b>", bullet),
         Paragraph("Pulmonary embolism, pulmonary hypertension, AVM", bullet),
         Paragraph("Sudden onset, pleuritic chest pain, S1Q3T3 on ECG, elevated D-dimer, CTPA diagnostic", bullet)],
        # Cardiac
        [Paragraph("<b>Cardiac</b>", bullet),
         Paragraph("Heart failure (LVF), cardiomyopathy, valvular disease, pericardial disease", bullet),
         Paragraph("Orthopnoea, PND, raised JVP, S3 gallop, elevated BNP, cardiomegaly on CXR", bullet)],
        # Pleural
        [Paragraph("<b>Pleural</b>", bullet),
         Paragraph("Pleural effusion, pneumothorax, mesothelioma", bullet),
         Paragraph("Reduced breath sounds, stony dullness (effusion), hyperresonance (pneumothorax), "
                   "tracheal deviation (tension PTX)", bullet)],
        # Upper airway
        [Paragraph("<b>Upper Airway</b>", bullet),
         Paragraph("Epiglottitis, anaphylaxis, foreign body, VCD", bullet),
         Paragraph("Stridor (inspiratory), acute onset, variable extrathoracic obstruction on flow-volume loop", bullet)],
        # Metabolic/Systemic
        [Paragraph("<b>Metabolic / Systemic</b>", bullet),
         Paragraph("Severe anaemia, metabolic acidosis, thyrotoxicosis, obesity hypoventilation", bullet),
         Paragraph("No primary lung/cardiac findings; anaemia (pallor, ↓Hb); Kussmaul breathing (DKA)", bullet)],
        # Neuromuscular
        [Paragraph("<b>Neuromuscular</b>", bullet),
         Paragraph("MND, Guillain-Barré, myasthenia gravis, diaphragm palsy", bullet),
         Paragraph("Paradoxical breathing, ↓MIP, orthopnoea when lying flat (diaphragm weakness)", bullet)],
        # Psychogenic
        [Paragraph("<b>Psychogenic</b>", bullet),
         Paragraph("Hyperventilation syndrome, panic disorder, VCD", bullet),
         Paragraph("Perioral tingling, Chvostek's sign (respiratory alkalosis), normal investigations", bullet)],
    ]
    ddx_table = Table(ddx_data, colWidths=[4*cm, 5.5*cm, 9*cm])
    ddx_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG]),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(ddx_table)
    story.append(Spacer(1, 0.3*cm))

    # 1.7 Management Framework
    story.append(Paragraph("7. Management Framework for Dyspnea", h2))
    story.append(Paragraph(
        "Management is <b>aetiology-directed</b>. However, the immediate priority is stabilisation:",
        body))
    mgmt_items = [
        "<b>Immediate:</b> Airway (position, oxygen therapy titrated to SpO₂ 94–98%; 88–92% in COPD), "
        "IV access, continuous monitoring (ECG, SpO₂, RR, BP)",
        "<b>Assess severity:</b> Clinical signs of impending respiratory failure → early NIV/intubation decision",
        "<b>Treat the underlying cause:</b> Bronchodilators (asthma/COPD) · Diuretics + nitrates (acute LVF) · "
        "Antibiotics (pneumonia/abscess) · Anticoagulation (PE) · Pleural drainage (effusion/pneumothorax)",
        "<b>Oxygen delivery:</b> Nasal prongs → Venturi mask → Non-rebreather mask → High-flow nasal oxygen (HFNO) → "
        "NIV (CPAP/BiPAP) → Intubation and mechanical ventilation",
        "<b>Supportive:</b> Posture (sitting upright); physiotherapy; smoking cessation; pulmonary rehabilitation (chronic)",
        "<b>Refractory dyspnoea:</b> Despite maximally treated chronic heart and lung disease — judicious opioids "
        "(oral morphine) can reduce the sensation of air hunger (Goldman-Cecil Medicine)",
        "<b>Multiple causes:</b> Since dyspnoea may result simultaneously from more than one condition, "
        "maintain all partially effective treatments while adding disease-specific therapy",
    ]
    for item in mgmt_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(PageBreak())

    # ══════════════════════════════════════════════════════════════════════════
    # PART 2 — LUNG ABSCESS
    # ══════════════════════════════════════════════════════════════════════════
    story.append(Paragraph("PART 2 — LUNG ABSCESS", h1))
    story.append(Spacer(1, 0.2*cm))

    # 2.1 Definition & Classification
    story.append(Paragraph("1. Definition", h2))
    story.append(Paragraph(
        "A <b>lung abscess</b> is a localised area of suppuration (necrosis and cavitation) within the pulmonary "
        "parenchyma, resulting in the formation of one or more cavities, usually a single dominant cavity "
        "<b>&gt;2 cm in diameter</b>. (Harrison's, 22e)",
        body))
    story.append(Spacer(1, 0.2*cm))

    story.append(Paragraph("2. Classification", h2))
    class2_data = [
        [Paragraph("<b>Parameter</b>", bullet),
         Paragraph("<b>Type A</b>", bullet),
         Paragraph("<b>Type B</b>", bullet)],
        [Paragraph("By Duration", bullet),
         Paragraph("<b>Acute</b>: &lt;4–6 weeks", bullet),
         Paragraph("<b>Chronic</b>: &gt;6 weeks (~40% of cases)", bullet)],
        [Paragraph("By Aetiology", bullet),
         Paragraph("<b>Primary</b> (~80%): aspiration in normal host; anaerobic organisms; "
                   "no underlying pulmonary/systemic disease", bullet),
         Paragraph("<b>Secondary</b> (~20%): underlying condition — obstruction (tumour, FB), "
                   "systemic disease (HIV, immunosuppression), haematogenous spread", bullet)],
        [Paragraph("By Smell", bullet),
         Paragraph("<b>Putrid</b>: foul-smelling sputum — virtually diagnostic of anaerobic abscess", bullet),
         Paragraph("<b>Non-putrid</b>: aerobic or mixed organisms", bullet)],
    ]
    class2_table = Table(class2_data, colWidths=[4*cm, 8*cm, 6.5*cm])
    class2_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG, WHITE]),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(class2_table)
    story.append(Spacer(1, 0.3*cm))

    # 2.2 Etiology / Risk Factors
    story.append(Paragraph("3. Etiology and Risk Factors", h2))
    story.append(Paragraph("<b>A. Mechanisms of Organism Entry:</b>", h3))
    etiol_items = [
        "<b>Aspiration</b> (most common) — infective material from carious teeth, infected sinuses/tonsils, "
        "gastric contents; occurs during anaesthesia, coma, alcoholic intoxication, seizures, bulbar dysfunction, "
        "neuromuscular disease, oesophageal dysmotility, GORD",
        "<b>Complication of necrotising pneumonia</b> — S. aureus, Streptococcus pyogenes, Klebsiella pneumoniae, "
        "Pseudomonas spp., rarely type 3 Pneumococcus",
        "<b>Bronchial obstruction</b> — lung cancer, foreign body; distal atelectasis → impaired drainage → abscess",
        "<b>Septic emboli</b> — right-sided infective endocarditis (tricuspid valve, commonly S. aureus); "
        "Lemierre's syndrome (Fusobacterium necrophorum — pharyngeal infection → jugular septic thrombophlebitis → lung)",
        "<b>Haematogenous spread</b> — staphylococcal bacteraemia → multiple abscesses",
        "<b>Spread from sub-diaphragmatic infection</b> — amoebic liver abscess (Entamoeba histolytica) "
        "→ right lower lobe basal abscess via trans-diaphragmatic spread",
    ]
    for item in etiol_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>B. Host Risk Factors for Aspiration:</b>", h3))
    risk2_items = [
        "Altered mental status — alcohol, drug overdose, general anaesthesia, seizures, head trauma",
        "Neurological disease — stroke, bulbar palsy, neuromuscular disease, Parkinson's disease",
        "Oesophageal disease — dysmotility, strictures, tumours, GORD, Zenker's diverticulum",
        "Poor dental hygiene — periodontal disease, gingivitis (colonisation with oral anaerobes)",
        "Immunocompromised states — HIV, organ transplant, haematological malignancy (→ secondary abscess)",
    ]
    for item in risk2_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph(
        "📌 Key Fact: Many physicians consider it extremely rare for lung abscesses to develop "
        "in the absence of teeth, as the gingival crevices act as the nidus for anaerobic colonisation. "
        "In edentulous patients, always suspect an obstructing endobronchial lesion, PE, or septic embolus. "
        "(Fishman's Pulmonary Diseases)",
        note_style))

    # 2.3 Microbiology
    story.append(Paragraph("4. Microbiology", h2))
    micro_data = [
        [Paragraph("<b>Clinical Scenario</b>", bullet), Paragraph("<b>Key Pathogens</b>", bullet)],
        [Paragraph("Primary (aspiration) lung abscess", bullet),
         Paragraph("Anaerobes: Prevotella spp., Fusobacterium spp., Bacteroides spp., "
                   "Peptostreptococcus spp., microaerophilic streptococci (milleri group)\n"
                   "Note: Anaerobes recoverable in up to 93% of cases; present as sole isolate in 46%", bullet)],
        [Paragraph("Secondary abscess (immunocompromised)", bullet),
         Paragraph("S. aureus (MSSA/MRSA), Gram-negative rods (Pseudomonas aeruginosa, Enterobacteriaceae, "
                   "Klebsiella), Nocardia, Aspergillus, Mucorales, Cryptococcus, Legionella, "
                   "Rhodococcus equi, PCP (Pneumocystis jirovecii)", bullet)],
        [Paragraph("Septic emboli", bullet),
         Paragraph("S. aureus (from endocarditis), Fusobacterium necrophorum (Lemierre's syndrome)", bullet)],
        [Paragraph("Endemic infections", bullet),
         Paragraph("MTB, MAC, M. kansasii; Coccidioides, Histoplasma, Blastomyces; "
                   "Entamoeba histolytica, Paragonimus westermani, Echinococcus (hydatid)", bullet)],
        [Paragraph("Post-viral", bullet),
         Paragraph("S. aureus superinfection after influenza; also Actinomyces spp.", bullet)],
        [Paragraph("Hospital-acquired / nosocomial", bullet),
         Paragraph("Gram-negative organisms with resistance patterns — Klebsiella, Pseudomonas, E. coli, "
                   "Enterobacter; MRSA", bullet)],
    ]
    micro_table = Table(micro_data, colWidths=[5*cm, 13.5*cm])
    micro_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG, WHITE, GREY_BG, WHITE, GREY_BG]),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(micro_table)
    story.append(Spacer(1, 0.3*cm))

    # 2.4 Pathophysiology
    story.append(Paragraph("5. Pathophysiology", h2))

    story.append(Paragraph("<b>Step-by-Step Pathogenesis (Primary Lung Abscess):</b>", h3))
    patho_steps = [
        "<b>Step 1 — Aspiration:</b> Oropharyngeal/gastric contents (laden with anaerobes and microaerophilic "
        "streptococci) are aspirated into the dependent lung segments — posteriorly when supine.",
        "<b>Step 2 — Insufficient Clearance:</b> The patient carries an overwhelming burden of aspirated material "
        "or is unable to clear the bacterial load (due to impaired mucociliary clearance, cough reflex, or phagocytic function).",
        "<b>Step 3 — Pneumonitis (Days 1–7):</b> Aspiration produces an initial chemical pneumonitis (partly from "
        "gastric acid injury), followed by bacterial inflammation. The polymicrobial flora, with synergistic "
        "virulence factors, begins tissue destruction.",
        "<b>Step 4 — Parenchymal Necrosis (Days 7–14):</b> Anaerobes with their synergistic virulence cause "
        "progressive liquefactive necrosis of lung parenchyma. The cavity forms over 1–2 weeks.",
        "<b>Step 5 — Cavitation:</b> As the necrotic focus enlarges, it ruptures into an adjacent airway. "
        "Partial drainage produces the characteristic air-fluid level on CXR. The cavity may become lined "
        "with regenerated epithelium.",
        "<b>Step 6 — Complications:</b> If untreated: extension to pleural space (empyema/bronchopleural fistula), "
        "pneumothorax, haematogenous spread to brain (cerebral abscess, meningitis), massive haemoptysis, "
        "or development of chronic lung abscess with surrounding bronchiectasis.",
    ]
    for i, step in enumerate(patho_steps):
        story.append(Paragraph(step, bullet))
        story.append(Spacer(1, 0.15*cm))

    story.append(Paragraph("<b>Location (Dependent on Mechanism):</b>", h3))
    loc_items = [
        "<b>Aspiration in recumbent position</b> → <b>Posterior segment of right upper lobe</b> and "
        "<b>apical segments of lower lobes</b> (right &gt; left; right mainstem bronchus less angulated)",
        "<b>Aspiration in upright/sitting position</b> → Basal segments of lower lobes",
        "<b>Necrotising pneumonia / bronchiectasis</b> → Multiple, basal, scattered",
        "<b>Haematogenous / septic emboli</b> → Multiple, any location, bilateral",
        "<b>Amoebic liver abscess spread</b> → Right lower lobe, basal (posterior segment)",
    ]
    for item in loc_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    story.append(Paragraph("<b>Morphology (Robbins &amp; Kumar):</b>", h3))
    story.append(Paragraph(
        "Abscesses range from a few mm to 5–6 cm. As suppuration enlarges, the abscess ruptures into airways "
        "→ air-fluid level on imaging. Occasionally ruptures into pleural cavity → bronchopleural fistula → "
        "pneumothorax / empyema. Septic material may embolise to brain → meningitis or cerebral abscess. "
        "Surrounding lung: local bronchial obstruction → bronchiectasis or emphysema in adjacent areas.",
        body))

    # 2.5 Clinical Features
    story.append(Paragraph("6. Clinical Features", h2))
    story.append(Paragraph("<b>Symptoms:</b>", h3))
    sym_items = [
        "Fever, cough, sputum production, chest pain (pleuritic if pleural involvement) — initially similar to pneumonia",
        "<b>Anaerobic abscess:</b> More chronic/indolent — fever, night sweats, weight loss, fatigue, anaemia (hallmarks)",
        "<b>Putrid abscess (anaerobic):</b> Foul-smelling, foul-tasting sputum / expectoration of large amounts of "
        "purulent sputum — virtually pathognomonic of anaerobic infection",
        "<b>Non-anaerobic (e.g., S. aureus):</b> More fulminant — high fevers, rapid progression",
        "Haemoptysis — may be massive (life-threatening complication)",
        "Dyspnoea — variable; worse with large abscess, complications, or underlying lung disease",
    ]
    for item in sym_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>Signs:</b>", h3))
    sign_items = [
        "Fever (may be high/remittent), tachycardia, tachypnoea",
        "Poor dentition / gingival disease — important clue to aspiration aetiology",
        "<b>Amphoric/cavernous breath sounds</b> on auscultation (hallmark of large cavity)",
        "Signs of consolidation (dullness, bronchial breathing) in surrounding area",
        "Digital clubbing — in chronic/long-standing cases",
        "Absent gag reflex — indicates ongoing aspiration risk",
        "Weight loss, pallor, signs of anaemia — in chronic abscess",
    ]
    for item in sign_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    # 2.6 Differential Diagnosis
    story.append(Paragraph("7. Differential Diagnosis — Cavitary Lung Lesions", h2))
    story.append(Paragraph(
        "The differential of a cavitary lung lesion is broad. The mnemonic <b>CAVITY</b> is useful:",
        body))

    story.append(Paragraph(
        "C — Carcinoma (squamous cell carcinoma most commonly cavitates; also sarcoma)\n"
        "A — Abscess (bacterial — typical/atypical) | Autoimmune vasculitis (GPA/Wegener's)\n"
        "V — Vascular (pulmonary infarct, septic emboli from endocarditis, AVM)\n"
        "I — Infection: TB (most common worldwide), NTM, Histoplasma, Coccidioides, Aspergillus, Mucor, Nocardia, Actinomyces, Entamoeba histolytica, Paragonimus\n"
        "T — Trauma (haematoma with secondary necrosis)\n"
        "Y — Young cysts (bronchogenic cysts, bullae, sequestration with infection)",
        note_style))

    ddx2_data = [
        [Paragraph("<b>Condition</b>", bullet),
         Paragraph("<b>Distinguishing Features</b>", bullet)],
        [Paragraph("Pulmonary TB", bullet),
         Paragraph("Upper lobe cavitation, AFB smear/culture, Mantoux/IGRA positive, contact history, "
                   "lymphadenopathy, constitutional symptoms, thin-walled cavity; "
                   "may have satellite lesions and tree-in-bud pattern on CT", bullet)],
        [Paragraph("Primary Lung Cancer (SCC)", bullet),
         Paragraph("Thick irregular wall, eccentric cavity, lobulated/spiculated margins on CT; "
                   "smoking history, age >50, weight loss; PET/biopsy confirms; "
                   "absence of fever/leukocytosis (unless superinfected)", bullet)],
        [Paragraph("Pulmonary Embolism with Infarction", bullet),
         Paragraph("Hampton's hump on CXR, pleural-based wedge opacity, no fever initially, "
                   "elevated D-dimer, CTPA diagnostic; cavity may form if infarct becomes necrotic", bullet)],
        [Paragraph("Septic Emboli / Endocarditis", bullet),
         Paragraph("Multiple bilateral peripheral cavities, IV drug use, cardiac murmur, "
                   "positive blood cultures (S. aureus), echocardiography shows vegetations; "
                   "Lemierre's: jugular vein thrombosis + pharyngitis prodrome", bullet)],
        [Paragraph("Granulomatosis with Polyangiitis (GPA)", bullet),
         Paragraph("Bilateral cavitary nodules + renal involvement (haematuria/proteinuria) + "
                   "upper airway disease; c-ANCA/PR3-ANCA positive; biopsy: necrotising granulomatous vasculitis", bullet)],
        [Paragraph("Fungal Infections (Aspergillus, Mucor, Histoplasma)", bullet),
         Paragraph("Immunocompromised host (neutropenia, transplant, DM); "
                   "Aspergilloma: fungal ball in pre-existing cavity, air-crescent sign on CT; "
                   "Mucor: rapidly progressive, black eschar, angioinvasion; serum galactomannan", bullet)],
        [Paragraph("Amoebic Lung Abscess", bullet),
         Paragraph("Travel to endemic area, right lower lobe basal location, "
                   "'chocolate sauce' sputum (anchovy paste), concurrent liver abscess on USG/CT, "
                   "amoeba serology; responds to metronidazole", bullet)],
        [Paragraph("Hydatid Cyst (Echinococcus)", bullet),
         Paragraph("Sheep-rearing area, 'water lily sign' on CXR/CT (floating membranes), "
                   "serological tests, eosinophilia; rupture → anaphylaxis risk", bullet)],
        [Paragraph("Cryptogenic Organising Pneumonia (COP)", bullet),
         Paragraph("Bilateral, migratory infiltrates ± cavitation; does not respond to antibiotics; "
                   "responds dramatically to corticosteroids; BAL shows organising pneumonia pattern", bullet)],
        [Paragraph("Pulmonary Sequestration", bullet),
         Paragraph("Non-functioning lung tissue with aberrant arterial supply; "
                   "recurrent pneumonia in same location; CT angiography diagnostic; "
                   "intralobar (no separate pleura) vs. extralobar", bullet)],
    ]
    ddx2_table = Table(ddx2_data, colWidths=[5*cm, 13.5*cm])
    ddx2_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG] * 6),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(ddx2_table)
    story.append(Spacer(1, 0.3*cm))

    story.append(Paragraph(
        "⚠ Exam Point: Lung abscess (infectious) is distinguished from cavitating carcinoma by: "
        "fever + leukocytosis in abscess; thick irregular eccentric wall in carcinoma (though overlap exists); "
        "always biopsy/bronchoscope if no response to 6 weeks of antibiotics to exclude malignancy.",
        warn_style))

    # 2.7 Diagnosis / Investigations
    story.append(Paragraph("8. Diagnosis and Investigations", h2))

    story.append(Paragraph("<b>A. Imaging:</b>", h3))
    img_items = [
        "<b>Chest X-ray (CXR):</b> Thick-walled cavity with air-fluid level — classic finding. "
        "Usually in posterior segment of RUL or apical segments of lower lobes. "
        "Useful to identify complications (effusion, empyema, pneumothorax)",
        "<b>CT Chest (preferred):</b> Better definition of cavity size, wall thickness, contents; "
        "earlier evidence of cavitation than CXR; identifies surrounding lung pathology (atelectasis, "
        "bronchiectasis); distinguishes lung abscess from empyema (important — affects management); "
        "may reveal underlying obstructing mass/tumour",
        "<b>POCUS (Point-of-Care Ultrasound):</b> Can identify peripheral abscess, adjacent pleural fluid; "
        "increasingly used at bedside for rapid assessment (2025 evidence — Porcel et al., Med Clin 2025)",
    ]
    for item in img_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>B. Microbiological Investigations:</b>", h3))
    micro_inv = [
        "<b>Sputum:</b> Gram's stain, culture — noninvasive; limited due to oropharyngeal contamination; "
        "culture may not reflect anaerobes; still recommended as first step",
        "<b>Blood cultures:</b> Yield pathogen in secondary abscesses / systemic sepsis",
        "<b>Bronchoscopy with BAL / protected brush specimen:</b> When secondary abscess suspected or "
        "empirical therapy fails; risk: aspiration of abscess contents into contralateral lung",
        "<b>CT-guided percutaneous needle aspiration:</b> When above methods fail; "
        "risks: pneumothorax, bronchopleural fistula, seeding of pleural space",
        "<b>Sputum smell:</b> Putrid odour = virtually diagnostic of anaerobic lung abscess",
        "<b>Emerging:</b> Molecular techniques (16S rRNA gene amplification) for improved pathogen ID",
        "<b>Serology:</b> Amoeba serology (ELISA), Aspergillus galactomannan, fungal cultures — "
        "in immunocompromised patients or failed empirical therapy",
    ]
    for item in micro_inv:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>C. Other Investigations:</b>", h3))
    other_inv = [
        "CBC: leukocytosis (bacterial), eosinophilia (parasitic/fungal), anaemia (chronic infection)",
        "CRP/ESR: elevated — non-specific markers of infection/inflammation",
        "LFTs + serum albumin: hypoalbuminaemia in chronic abscess; LFT abnormalities → amoebic liver abscess",
        "AFB smear and culture (3 samples): Exclude TB — always in endemic areas",
        "Bronchoscopy: essential to exclude endobronchial obstruction (tumour, foreign body) — "
        "especially in non-resolving, non-aspirating abscess or edentulous patient",
        "PET-CT / tissue biopsy: When malignancy cannot be excluded",
    ]
    for item in other_inv:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    # 2.8 MANAGEMENT
    story.append(Paragraph("9. Management of Lung Abscess", h2))
    story.append(Paragraph(
        "Management includes <b>antibiotics</b> (primary), <b>postural drainage</b>, and "
        "<b>interventional procedures</b> when needed. Surgery is a last resort.",
        body))

    story.append(Paragraph("<b>A. Antibiotic Therapy (Primary Treatment):</b>", h3))
    story.append(Paragraph(
        "Antibiotics established themselves as the primary treatment in the 1940–1950s, largely replacing surgery. "
        "For many decades penicillin was standard; however, because oral anaerobes produce β-lactamases, "
        "<b>clindamycin has proved superior to penicillin in clinical trials.</b> (Harrison's 22e)",
        body))

    abx_data = [
        [Paragraph("<b>Scenario</b>", bullet),
         Paragraph("<b>First-Line Regimen</b>", bullet),
         Paragraph("<b>Duration</b>", bullet)],
        [Paragraph("<b>Primary Lung Abscess</b>\n(aspiration, anaerobic)", bullet),
         Paragraph(
             "Option 1: <b>Clindamycin</b> 600 mg IV TDS → (on improvement) 300 mg PO QDS\n\n"
             "Option 2: <b>IV β-lactam/β-lactamase inhibitor</b> (e.g., ampicillin-sulbactam, "
             "piperacillin-tazobactam) → <b>Amoxicillin-clavulanate PO</b> once stable\n\n"
             "Alternative: <b>Moxifloxacin</b> 400 mg/day PO (small study: comparable to ampicillin-sulbactam)\n\n"
             "<font color='#c0392b'>⚠ Metronidazole ALONE is NOT adequate — does not cover microaerophilic streptococci</font>",
             bullet),
         Paragraph("3–14 weeks (until imaging shows clearance or small scar).\n\n"
                   "≥6 weeks associated with better outcomes.", bullet)],
        [Paragraph("<b>Secondary Lung Abscess</b>\n(immunocompromised / identified pathogen)", bullet),
         Paragraph("Target therapy based on identified pathogen (cultures essential).\n\n"
                   "Broad coverage for Gram-negatives (including Pseudomonas): Piperacillin-tazobactam, "
                   "carbapenems (meropenem/imipenem) ± anti-MRSA agent (vancomycin/linezolid) if MRSA suspected.\n\n"
                   "Treat underlying condition (relieve obstruction, treat immunosuppression cause).", bullet),
         Paragraph("Until imaging confirms abscess resolution (prolonged — variable).", bullet)],
        [Paragraph("<b>TB / Atypical Mycobacteria</b>", bullet),
         Paragraph("Standard anti-TB regimen (2HRZE/4HR); NTM — per species-specific protocol", bullet),
         Paragraph("TB: 6 months (or longer for drug-resistant TB)", bullet)],
        [Paragraph("<b>Amoebic Lung Abscess</b>", bullet),
         Paragraph("<b>Metronidazole</b> 500–750 mg TDS × 7–10 days + luminal agent (diloxanide furoate)", bullet),
         Paragraph("10–14 days", bullet)],
        [Paragraph("<b>Fungal (Aspergillus)</b>", bullet),
         Paragraph("Voriconazole (first line); Amphotericin B (alternative)\nMucor: Amphotericin B + surgery", bullet),
         Paragraph("Prolonged (weeks to months)", bullet)],
    ]
    abx_table = Table(abx_data, colWidths=[4*cm, 10.5*cm, 4*cm])
    abx_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), DARK_BLUE),
        ("TEXTCOLOR", (0, 0), (-1, 0), WHITE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [WHITE, GREY_BG, WHITE, GREY_BG, WHITE]),
        ("BOX", (0, 0), (-1, -1), 0.5, GREY_LINE),
        ("INNERGRID", (0, 0), (-1, -1), 0.3, GREY_LINE),
        ("VALIGN", (0, 0), (-1, -1), "TOP"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
    ]))
    story.append(abx_table)
    story.append(Spacer(1, 0.3*cm))

    story.append(Paragraph("<b>B. Supportive Measures:</b>", h3))
    supp_items = [
        "<b>Postural drainage</b> — physiotherapy, positioning to facilitate drainage through the airway",
        "<b>Adequate nutrition</b> — high-protein diet; nutritional support in malnourished/chronic cases",
        "<b>Oxygen therapy</b> if hypoxic",
        "<b>Treat aspiration risk</b> — oral hygiene, dental care (reduces anaerobic burden), elevate head of bed, "
        "PPI for GORD, address swallowing dysfunction (SLP assessment)",
        "<b>Hydration</b> and management of fever/sepsis",
    ]
    for item in supp_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Paragraph("<b>C. When Antibiotics Fail — Interventional Options:</b>", h3))
    story.append(Paragraph(
        "As many as <b>10–20% of patients</b> do not respond to antibiotics, with continued fevers and "
        "progression of abscess cavity on imaging. An abscess <b>&gt;6–8 cm</b> is less likely to respond to "
        "antibiotics alone. (Harrison's 22e)",
        body))
    interv_items = [
        "<b>Reassess diagnosis</b> — repeat CT, bronchoscopy (exclude malignancy, FB, unusual pathogen); "
        "additional cultures/serology",
        "<b>Percutaneous CT-guided drainage</b> — for patients who fail antibiotics and are poor surgical candidates; "
        "complications: bacterial contamination of pleural space, pneumothorax, haemothorax; "
        "risk increased if traversing normal lung parenchyma (Hadid et al., J Thorac Dis 2024)",
        "<b>Bronchoscopic drainage / endobronchial aspiration</b> — can facilitate drainage and allow culture",
        "<b>Surgical resection (lobectomy)</b> — definitive treatment for persistent, non-responsive abscess; "
        "also for life-threatening haemoptysis; goal: balance procedural morbidity vs. need to clear infection; "
        "drainage should be present (not active) at time of surgery to reduce contamination risk",
    ]
    for item in interv_items:
        story.append(Paragraph(f"• {item}", bullet))

    # 2.9 Complications
    story.append(Paragraph("10. Complications", h2))
    comp_items = [
        "<b>Empyema thoracis</b> — extension to pleural space (most common serious complication); "
        "requires urgent intercostal drain + antibiotics",
        "<b>Bronchopleural fistula</b> — communication between bronchial tree and pleural space; "
        "pyopneumothorax; difficult to manage",
        "<b>Life-threatening haemoptysis</b> — erosion of pulmonary vessel wall; "
        "may require bronchial artery embolisation or emergency surgery",
        "<b>Cerebral abscess / Meningitis</b> — haematogenous spread of septic emboli to CNS",
        "<b>Bacteraemia / Septicaemia</b> — systemic spread; septic shock",
        "<b>Chronic lung abscess</b> — persistent cavity >6 weeks; "
        "associated bronchiectasis, recurrent infection, amyloidosis (long-standing)",
        "<b>Pneumatocele formation</b> — persistent cystic changes; "
        "larger cavity size on presentation correlates with pneumatocele and bronchiectasis development",
        "<b>Contralateral lung spillage</b> — during bronchoscopy or posture changes; "
        "aspiration of abscess contents → widespread necrotising pneumonia",
        "<b>Respiratory failure</b> — in severe/bilateral disease or with underlying lung compromise",
    ]
    for item in comp_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    # 2.10 Prognosis
    story.append(Paragraph("11. Prognosis and Poor Prognostic Factors", h2))
    story.append(Paragraph(
        "With appropriate antibiotic therapy, <b>primary lung abscess mortality can be as low as 2%</b>. "
        "Secondary lung abscess has significantly higher mortality — <b>up to 75%</b> in some case series.",
        body))
    prog_items = [
        "Age >60 years",
        "Malignancy-related abscess",
        "Presence of aerobic bacteria (non-anaerobic abscess)",
        "Sepsis at presentation",
        "Symptom duration >8 weeks",
        "Abscess size >6 cm",
        "Immunocompromised state",
        "Secondary lung abscess (underlying condition)",
    ]
    story.append(Paragraph("<b>Poor Prognostic Factors:</b>", h3))
    for item in prog_items:
        story.append(Paragraph(f"• {item}", bullet))
    story.append(Spacer(1, 0.2*cm))

    # 2.11 Prevention
    story.append(Paragraph("12. Prevention", h2))
    prev_items = [
        "Address aspiration risk: airway protection (cuffed ET tube during anaesthesia), correct positioning",
        "Oral hygiene and dental care — reduces colonisation of gingival crevices with anaerobes",
        "Prophylactic antibiotics in high-risk aspiration (selected cases)",
        "Management of underlying risk factors (alcohol, seizures, GORD, dysphagia)",
        "Early and appropriate antibiotic treatment of necrotising pneumonia",
        "Bronchoscopy to relieve endobronchial obstruction (foreign body, tumour)",
    ]
    for item in prev_items:
        story.append(Paragraph(f"• {item}", bullet))

    story.append(Spacer(1, 0.4*cm))
    story.append(HRFlowable(width="100%", thickness=1.5, color=MID_BLUE, spaceAfter=10))

    # ── QUICK REVISION SUMMARY BOX ──────────────────────────────────────────
    story.append(Paragraph("QUICK REVISION — HIGH-YIELD EXAM POINTS", h1))
    story.append(Spacer(1, 0.2*cm))

    qr_items = [
        "<b>Dyspnea definition:</b> Sensation of difficult, labored, or UNPLEASANT breathing — "
        "'unpleasant' is key because normal exertional breathlessness is excluded.",
        "<b>BNP in acute dyspnoea:</b> Extremely helpful — distinguishes heart failure from pulmonary causes "
        "(BNP >400 pg/mL favours heart failure).",
        "<b>Lung abscess definition:</b> Necrosis + cavitation of lung by microbial infection; "
        "usually single dominant cavity >2 cm.",
        "<b>Most common aetiology:</b> Aspiration of anaerobes from gingival crevices — "
        "right side > left; posterior segment RUL and apical segments of lower lobes.",
        "<b>Microbiology:</b> Anaerobes in up to 93%; polymicrobial most common. "
        "Putrid sputum = virtually diagnostic of anaerobic abscess.",
        "<b>Cavitation on CXR:</b> Air-fluid level in thick-walled cavity — takes 1–2 weeks to form.",
        "<b>1st-line treatment:</b> Clindamycin IV → PO (superior to penicillin because β-lactamase-producing anaerobes).",
        "<b>Metronidazole alone = INADEQUATE</b> — does not cover microaerophilic streptococci.",
        "<b>Duration:</b> Until imaging resolution — minimum 3–4 weeks, often 6–14 weeks.",
        "<b>Failure indicators:</b> No response in 7 days; abscess >6–8 cm; ongoing fever/progression "
        "→ reassess diagnosis, consider drainage, consider surgical resection.",
        "<b>Lemierre's syndrome:</b> Fusobacterium necrophorum → pharyngitis → jugular vein septic thrombophlebitis "
        "→ septic pulmonary emboli → multiple cavitary lung lesions.",
        "<b>In edentulous patients with lung abscess:</b> Always suspect underlying obstructing endobronchial lesion "
        "— bronchoscopy is mandatory.",
        "<b>Amoebic abscess:</b> Right lower lobe, basal; chocolate-sauce sputum; associated liver abscess; "
        "treat with metronidazole.",
        "<b>Prognosis:</b> Primary abscess mortality ~2%; secondary abscess up to 75%. "
        "Poor factors: age >60, malignancy, size >6 cm, aerobic bacteria, sepsis at presentation.",
    ]
    for i, item in enumerate(qr_items):
        bg = LIGHT_BLUE if i % 2 == 0 else colors.HexColor("#f0f9ff")
        qr_style = ParagraphStyle(f"qr_{i}", parent=body,
            backColor=bg, leftIndent=8, rightIndent=4,
            borderPad=5, spaceAfter=4, leading=14)
        story.append(Paragraph(f"{'●'} {item}", qr_style))

    story.append(Spacer(1, 0.5*cm))
    story.append(HRFlowable(width="100%", thickness=1, color=GREY_LINE, spaceAfter=6))
    story.append(Paragraph(
        "<b>References:</b> Harrison's Principles of Internal Medicine 22e (2025, McGraw-Hill) · "
        "Goldman-Cecil Medicine, International Edition · Robbins &amp; Kumar Basic Pathology · "
        "Fishman's Pulmonary Diseases and Disorders, 2-Volume Set · "
        "Hadid W et al. Lung abscess: the non-conservative management — a narrative review. "
        "J Thorac Dis. 2024 [PMID: 38883669] · "
        "Porcel JM et al. Point-of-care ultrasound in pulmonary and pleural infections. "
        "Med Clin (Barc). 2025 [PMID: 40997476]",
        ref_style))

    doc.build(story)
    print(f"PDF created: {OUTPUT_PATH}")

if __name__ == "__main__":
    make_doc()