Chronic Inflammation MCQ — NEET PG Practice Question | NEETPGAI
Chronic Inflammation
medium
microscope Pathology
A 58-year-old woman presents with progressive dyspnea and bilateral hilar lymphadenopathy on chest X-ray. Serum calcium is elevated at 11.8 mg/dL. Histopathology of the mediastinal lymph node shows non-caseating granulomas composed of epithelioid histiocytes and multinucleated giant cells without central necrosis. Which is the most common cause of non-caseating chronic granulomatous inflammation in this patient?
A. Histoplasmosis
B. Tuberculosis
C. Berylliosis
D. Sarcoidosis
Explanation
Diagnosis: Sarcoidosis with Non-Caseating Granulomas
Key Point
Sarcoidosis is the most common cause of non-caseating granulomatous inflammation in developed countries and is a leading differential diagnosis for granulomatous disease in any patient with systemic symptoms and lymphadenopathy.
Pathophysiology of Non-Caseating Granulomas in Sarcoidosis
1.
Unknown antigen (possibly organic or inorganic) triggers Th1/Th17-mediated immune response
2.
Activated macrophages and epithelioid cells aggregate
3.
Multinucleated giant cells form from fusion of epithelioid cells
4.
Absence of central caseous necrosis — distinguishes from TB
5.
Fibroblasts encapsulate the granuloma
High-YieldNEET PG
The distinction between caseating (TB, fungal) and non-caseating (sarcoidosis, berylliosis) granulomas is critical for diagnosis. Sarcoidosis accounts for >90% of non-caseating granulomas in Western populations.
Mnemonic: CREST — Calcium elevation, Respiratory symptoms, Erythema nodosum, Salivary gland enlargement, Thoracic (hilar) lymphadenopathy — classic features of sarcoidosis.
Clinical Pearl
Hypercalcemia in sarcoidosis occurs because activated macrophages in granulomas produce 1α-hydroxylase, converting 25-hydroxyvitamin D to the active 1,25-dihydroxyvitamin D, leading to increased intestinal calcium absorption.
Differential: Caseating vs Non-Caseating Granulomas
Table
Feature
Caseating
Non-Caseating
Central necrosis
Present (cheese-like)
Absent
Common causes
TB, fungal infections
Sarcoidosis, berylliosis, Crohn's disease
Hypercalcemia
Rare
Common (sarcoidosis)
AFB stain
Often positive in TB
Negative
Geographic variation
TB universal; fungi regional
Sarcoidosis worldwide
Robbins 10e Ch 8
Practice similar questions
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.
