Atypical presentation of progressive disseminated histoplasmosis in a patient recently diagnosed with AIDS

Area of Science:

• Infectious Diseases
• Immunology
• Mycology

Background:

• Opportunistic infections are common in patients with Acquired Immunodeficiency Syndrome (AIDS).
• Progressive disseminated histoplasmosis (PDH) is a serious fungal infection caused by Histoplasma capsulatum.
• PDH can present with diverse symptoms, complicating diagnosis in immunocompromised individuals.

Observation:

• Patients with AIDS may experience primary or reactivated latent Histoplasma infections.
• Immune reconstitution inflammatory syndrome (IRIS) can unmask latent infections after antiretroviral therapy initiation.
• PDH diagnosis is challenging due to overlapping symptoms with other opportunistic infections and variable clinical presentations.

Findings:

• Serum and urine antigen tests are sensitive but not always conclusive for PDH.
• Negative antigen and antibody tests do not exclude Histoplasma capsulatum infection.
• Biopsy demonstrating narrow-based budding yeast is essential for definitive PDH diagnosis, especially in ambiguous cases.

Implications:

• High clinical suspicion for PDH is crucial in AIDS patients, even with negative serological or antigen tests.
• Biopsy histopathology remains the gold standard for confirming PDH.
• Early and accurate diagnosis of PDH is vital for timely treatment and improved outcomes in patients with AIDS.