A 45-year-old farmer from Northeast India presents with low-grade fever, progressive weight loss, night sweats, and productive cough. Chest CT reveals upper lobe cavitary lesions. Lung biopsy shows granulomatous inflammation with caseous necrosis and abundant histiocyte infiltration. What is the most likely diagnosis?

1. A

   A. Aspergillosis

2. B

   B. Histoplasmosis

3. C

   C. Sarcoidosis

4. D

   D. Cryptococcosis

Appeared in: INI-CET EXAM -2026

Explanation

• The patient's occupation (farmer) and location (Northeast India) place him at high risk for histoplasmosis, an endemic mycosis found in soil contaminated with bird or bat droppings.
• The clinical presentation of chronic cough, low-grade fever, night sweats, and weight loss, combined with upper lobe cavitary lesions on CT, perfectly mimics reactivation tuberculosis, a classic presentation of chronic pulmonary histoplasmosis.
• The lung biopsy finding of granulomatous inflammation with caseous necrosis is consistent with histoplasmosis.
• The presence of abundant histiocytes (macrophages) is a hallmark, as the yeast form of Histoplasma capsulatum multiplies within these cells.

Why Other Options Were Wrong

• Option A: Aspergillosis typically manifests as a fungus ball (aspergilloma) within a pre-existing lung cavity or as acute invasive disease in severely immunocompromised patients, neither of which matches this patient's primary cavitary presentation.
• Option C: Sarcoidosis is characterized by the formation of non-caseating granulomas. The biopsy report explicitly mentions caseous necrosis, which is a key finding that argues against a diagnosis of sarcoidosis.
• Option D: Cryptococcosis primarily affects immunocompromised individuals, such as those with advanced HIV/AIDS. While it can cause pulmonary nodules or infiltrates, a TB-like cavitary presentation in an apparently immunocompetent person is less common.

Related Visual

Clinical Relevance

• Nursing practice connection: Use the key finding related to Differential diagnosis of chronic pulmonary infections with cavitary lesions, particularly endemic mycoses mimicking tuberculosis to guide bedside assessment, documentation, and the next nursing action.
• This case highlights the critical importance of considering endemic fungal infections like histoplasmosis in the differential diagnosis of patients presenting with tuberculosis-like symptoms, especially if they are from or have traveled to endemic regions.
• Failure to consider histoplasmosis can lead to misdiagnosis as TB, resulting in inappropriate treatment with anti-tubercular drugs and progression of the fungal disease.
• A thorough occupational and travel history is a crucial part of the diagnostic workup in patients with chronic respiratory illness.

How to Approach the Question

• First, analyze the patient's demographic and social history: a 45-year-old farmer from Northeast India. This points towards environmental and geographical risk factors.
• Next, evaluate the clinical symptoms: low-grade fever, weight loss, night sweats, and productive cough. Recognize this as a classic 'B-symptom' constellation, common in chronic infections like TB.
• Correlate the symptoms with the imaging findings: upper lobe cavitary lesions. This further strengthens the suspicion of TB but should also prompt consideration of its mimics.
• The most crucial step is to interpret the histopathology report: 'granulomatous inflammation with caseous necrosis and abundant histiocyte infiltration'.
• Differentiate the options based on this key finding. Caseous necrosis rules out sarcoidosis (which has non-caseating granulomas). The overall picture of a TB-mimic in a farmer from an endemic area makes histoplasmosis far more likely than aspergillosis or cryptococcosis.

Concept Tested & Keywords

• Concept Tested: Differential diagnosis of chronic pulmonary infections with cavitary lesions, particularly endemic mycoses mimicking tuberculosis.
• Stem keywords: farmer, Northeast India, low-grade fever, weight loss, night sweats, productive cough, upper lobe cavitary lesions, granulomatous inflammation
• Lead-in keywords: most likely diagnosis
• Clinical cues: Patient's occupation as a farmer suggests environmental exposure to soil-based pathogens.
• Clinical cues: Geographic location in Northeast India is a clue for endemic fungal infections.

Question ID

QhY656Ir8oF4QXES8flyfl

Copy ID

Reference Book

E6 Medicine Harrison 22e Part 1 p. 1735-1737