Abstract
Histoplasmosis is a mycosis caused by Histoplasma capsulatum, a dimorphic fungus endemic to areas with nitrogen-rich soil, like the one contaminated with bird and bat excrement. Patients with a deficient immune response are especially at risk for developing invasive infections, such as disseminated histoplasmosis, and secondary immunodeficiency can be a consequence of malnutrition. This case report presents a 15-month-old male infant with malnutrition who presented with signs and symptoms of disseminated histoplasmosis, including fever, malaise, weight loss, cough, and diarrhea. The infant came from a geographic area where histoplasmosis is endemic, and he was a member of a cultural group with a higher prevalence of histoplasmosis than the general population. On physical examination, hepatosplenomegaly, lymphadenopathy, and lung crackles were found, which are common in most patients with histoplasmosis. The keystone of diagnosis of H. capsulatum infection is antigen detection, but the criterion standard is isolation of the organism from body specimens through laboratory culture. Histological diagnosis is especially useful for rapid diagnosis. Treatment of disseminated histoplasmosis in the pediatric population consists of deoxycholate amphotericin B for four to six weeks followed by itraconazole to complete a total of three months of treatment. Despite the involvement of multiple organ systems, the patient recovered satisfactorily after the completion of amphotericin B treatment for one month and the resolution of his malnourishment.