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IMAGE 1 - Chest CT Scan (Two films side by side)

Findings:

• Multiple large, thick-walled cavitary lesions in bilateral upper lobes, more extensive on the right
• Extensive volume loss and fibrosis in bilateral upper lobes with architectural distortion
• Prominent traction bronchiectasis within fibrotic regions (upper and mid zones)
• Tree-in-bud pattern in adjacent lung segments - strongly suggests active bronchogenic spread
• Patchy consolidation and ground-glass opacities surrounding the cavities

• Mild-to-moderate mediastinal lymphadenopathy (pretracheal, paratracheal, subcarinal stations) - likely reactive
• Heart size normal; great vessels appear normal

Impression:

1. Post-primary / Reactivation Pulmonary Tuberculosis (most likely in this geographic context)
2. Non-Tuberculous Mycobacterial (NTM) infection
3. Chronic Pulmonary Aspergillosis (possibly co-existing)

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IMAGE 2 - MRI Lower Leg (Sagittal/Coronal views)

Findings:

• Diffuse high signal intensity tracking through deep and superficial soft tissue planes of the calf - extensive myositis and fasciitis
• Longitudinal fluid collections along deep fascial boundaries - highly suspicious for abscess formation or phlegmon
• Patchy increased marrow signal in the tibial shaft - raises suspicion for osteomyelitis or reactive osteitis

Impression:

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IMAGE 3 - MRI Lower Leg (Axial views - eSTIR and T2 TSE sequences)

Findings:

• Large, well-defined, hyperintense soft tissue mass in the posterior compartment (gastrocnemius/soleus region)
• Highly T2/STIR-bright with thin hypointense capsule - suggests fluid-rich, cystic, or vascular content
• Internal septations/lobulations visible in some slices
• Perilesional edema in adjacent subcutaneous fat and muscles
• Prominent/dilated vascular channels near the lesion
• Mass effect displacing adjacent muscles; no obvious cortical bone destruction

Impression:

1. Peripheral Nerve Sheath Tumor (Schwannoma) - most consistent
2. Intramuscular Myxoma
3. Soft Tissue Sarcoma must be excluded (any large deep soft tissue mass in a 46-year-old requires biopsy)
4. Vascular malformation / Hemangioma

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IMAGE 4 - MRI Thigh (Axial views)

Findings:

• Very large, heterogeneous, expansile soft tissue mass in the anterior/anteromedial thigh compartment (likely involving vastus medialis/intermedius)
• Massive - occupies most of the cross-sectional area in upper slices
• Markedly heterogeneous signal: mixed hyperintense and hypointense areas with internal septations and nodular components - suggests necrosis, cystic degeneration, or myxoid change
• Severe displacement of surrounding musculature
• Closely abuts the femur; no gross cortical destruction confirmed, though periosteal involvement cannot be excluded on these views

Impression:

1. Liposarcoma (myxoid or pleomorphic variant)
2. Undifferentiated Pleomorphic Sarcoma (UPS)
3. Synovial Sarcoma

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Summary - Integrated Clinical Picture

Clinical Concerns:

• The combination of a large thigh mass + active pulmonary disease raises the question of whether the pulmonary findings could represent metastatic disease to the lungs from a primary soft tissue sarcoma, rather than purely TB - though the CT pattern is more consistent with TB/granulomatous disease
• Active TB in the setting of a potential sarcoma would have critical implications for immunosuppressive chemotherapy
• All findings require formal radiologist review, MDT (multidisciplinary team) discussion, and likely tissue biopsy of the thigh mass as the immediate next step

Disclaimer: This is an AI-assisted image interpretation for educational/informational support only. It does not replace a formal radiologist report, clinical examination, or specialist consultation. The treating physician should review original DICOM images with the radiologist.

What is a Phlegmon?

Key Distinction: Phlegmon vs. Abscess

How It Looks on Imaging

Where Phlegmons Occur

• Neck - complicating dental, tonsillar, or salivary gland infections
• Periappendiceal - around a perforated or inflamed appendix (sometimes treated with antibiotics alone rather than immediate surgery)
• Pericolic - surrounding diverticulitis (Hinchey Stage I classification)
• Pancreatic - in severe pancreatitis (infected pancreatic phlegmon - importantly, draining a sterile pancreatic phlegmon risks contaminating it)
• Paraspinal/Epidural - complicating discitis or vertebral osteomyelitis
• Soft tissue of limbs - as seen in Somnath Biswas's leg MRI, where the diffuse tracking fluid signal through fascial planes represents phlegmonous infection

Clinical Importance

• If it's an abscess - drain it
• If it's a phlegmon - treat with antibiotics and watch for progression to abscess

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Approach to Jaundice - MD Medicine Year 1

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1. Definition

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2. Bilirubin Metabolism - The Backbone

RBC destruction (spleen/RES)
        ↓
  Heme → Biliverdin → Unconjugated bilirubin (UCB)
  [Lipid-soluble, albumin-bound, NOT filtered by kidneys]
        ↓ (transported to liver)
  Hepatocyte uptake → Conjugation with glucuronic acid (UGT1A1 enzyme)
  → Conjugated bilirubin (CB) [Water-soluble]
        ↓
  Excreted into bile → Intestine
  → Urobilinogen (some reabsorbed → urine) → Stercobilin (stool color)

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3. Classification of Jaundice

A. Prehepatic (Pre-hepatic) - Unconjugated hyperbilirubinemia

B. Intrahepatic - Mixed or conjugated hyperbilirubinemia

C. Posthepatic (Obstructive / Cholestatic) - Conjugated hyperbilirubinemia

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4. History - What to Ask

Key questions:

• Onset: sudden (stone, hepatitis) vs. gradual and painless (malignancy)?
• Progression: waxing-waning (hemolysis, Gilbert) vs. progressive (malignancy)?
• Duration?

• Alcohol intake (amount, duration)
• Drug history - including OTC, herbal, ayurvedic preparations
• Blood transfusions, IV drug use, tattoos (hepatitis B/C risk)
• Sexual history
• Travel history (hepatitis A/E - feco-oral; malaria)
• Family history of liver disease, jaundice, or hemolytic anemia
• Prior biliary surgery or ERCP
• Occupation (exposure to hepatotoxins)

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5. Physical Examination

Systematic examination:

• Scratch marks → pruritus → cholestasis
• Spider nevi (>5 on upper body) → chronic liver disease
• Palmar erythema, leukonychia → chronic liver disease
• Xanthelasma / xanthomas → prolonged cholestasis (PBC)
• Caput medusae → portal hypertension
• Purpura/bruising → coagulopathy

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6. Initial Laboratory Investigations

Tier 1 - Mandatory baseline:

Interpreting the Pattern:

Urine findings at bedside:

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7. Diagnostic Algorithm

1. ALP or aminotransferases elevated?
   • No → Evaluate for hemolysis or hereditary hyperbilirubinemia (Gilbert, Crigler-Najjar)
   • Yes → Go to step 2
2. Is biliary tract obstruction a consideration clinically?
   • No → Send biochemical studies for specific liver disease (viral serology, autoimmune, metabolic)
   • Yes → Go to step 3
3. Abdominal Ultrasound or CT (first-line imaging)
   • Dilated bile ducts → ERCP or Transhepatic Cholangiography → therapeutic intervention
   • Non-dilated bile ducts → assess clinical likelihood of obstruction
4. Clinical likelihood of obstruction?
   • Low → Biochemical studies for hepatic disease
   • High → ERCP/THC directly
   • Intermediate → MRCP or EUS

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8. Tier 2 - Specific Investigations (Based on the Working Diagnosis)

For hepatocellular disease:

For hemolysis:

• Peripheral blood smear (spherocytes, schistocytes, sickle cells)
• Reticulocyte count (elevated in hemolysis)
• Coombs test (direct and indirect)
• LDH (elevated), Haptoglobin (decreased)
• G6PD assay

For obstruction:

• Abdominal USG (first line - CBD dilation, stones, mass)
• MRCP (gold standard non-invasive for biliary anatomy)
• CT abdomen with contrast (mass lesions, lymphadenopathy)
• ERCP (diagnostic + therapeutic - stone extraction, stenting)
• EUS (periampullary lesions, small CBD stones)
• Tumor markers: CA 19-9 (pancreatic/biliary malignancy), CEA, AFP

Liver biopsy indications:

• Persistent unexplained jaundice
• Suspected autoimmune hepatitis, PBC, Wilson disease, hemochromatosis
• Fibrosis staging in chronic liver disease
• NOT routinely needed in acute viral hepatitis

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9. Red Flags - Do Not Miss

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10. Management Principles

• Stop hepatotoxic drugs
• Antiviral therapy for hepatitis B/C
• Steroids for autoimmune hepatitis
• Abstinence for alcoholic liver disease
• UDCA for PBC, intrahepatic cholestasis of pregnancy

• CBD stone: ERCP + sphincterotomy + stone extraction
• Benign stricture: balloon dilation ± stent (ERCP or interventional radiology)
• Malignancy: surgical resection if resectable; biliary stenting for palliation
• Cholangitis: IV antibiotics (cover gram-negatives + anaerobes) + emergency biliary drainage

• Low-fat diet in cholestasis
• Fat-soluble vitamins (A, D, E, K) supplementation in prolonged cholestasis
• Antihistamines / cholestyramine for pruritus
• Avoid nephrotoxic drugs

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Quick Summary Table

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Quick logic to memorize:

1. Check bilirubin fractions first - unconjugated vs. conjugated
2. Unconjugated → think prehepatic (hemolysis, Gilbert)
3. Conjugated → look at the enzyme pattern:
   • ALT/AST >> ALP → hepatocellular (hepatitis, cirrhosis)
   • ALP >> ALT/AST → cholestatic → do USG
4. USG shows dilated ducts → mechanical obstruction → ERCP/MRCP
5. USG shows no dilation → intrahepatic cholestasis (PBC, drugs, pregnancy)