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Gastrointestinal histoplasmosis presenting as colonic pseudotumour
S Sehgal1, R Chawla, P S Loomba
1Department of Microbiology, GB Pant Hospital, New Delhi-110 002, India.
Indian Journal of Medical Microbiology
|May 1, 2008
Summary
This case study highlights a rare instance of gastrointestinal histoplasmosis in an HIV-positive man, initially misdiagnosed as colon cancer. Early diagnosis is crucial for effective treatment of this opportunistic infection.
Area of Science:
- Mycology
- Infectious Diseases
- Gastroenterology
Background:
- Gastrointestinal histoplasmosis is a rare opportunistic infection, particularly in immunocompromised individuals.
- Histoplasma capsulatum can cause diverse clinical manifestations, often mimicking other gastrointestinal pathologies.
Observation:
- A 45-year-old HIV-positive male presented with symptoms mimicking colonic cancer, including abdominal pain and weight loss.
- Colonoscopy revealed a sigmoid colon stricture and ulcerated growth, leading to a presumptive diagnosis of malignancy.
- Histopathological examination of surgical specimens confirmed Histoplasma capsulatum yeast cells.
Findings:
- The patient developed pulmonary involvement with fluffy opacities on chest X-ray and positive sputum for H. capsulatum.
- Despite treatment with amphotericin B, the patient succumbed to the infection post-operatively.
- The case underscores the diagnostic challenges posed by atypical presentations of histoplasmosis.
Implications:
- This report emphasizes the importance of considering opportunistic infections like histoplasmosis in HIV-positive patients with gastrointestinal symptoms.
- Increased awareness and prompt diagnostic workup are essential to prevent misdiagnosis and improve outcomes.
- This is the first reported case of gastrointestinal histoplasmosis presenting as a colonic pseudotumor in India.
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