Treatment of disseminated histoplasmosis in advanced HIV using itraconazole with increased bioavailability

Disseminated histoplasmosis (DH), an endemic mycosis caused by the dimorphic fungus Histoplasma capsulatum, is a life-threatening infection in immunocompromised hosts. A patient with newly-diagnosed human immunodeficiency virus (HIV) infection presented with a violaceous, raised, indurated, pruritic rash over the face, arms and trunk on a background of significant weight loss, fevers with sweats, diarrhoea and worsening shortness of breath. His CD4+ T cell count was 14 cells/µl (12%). Histoplasmosis was diagnosed from histology, fungal stain and culture of skin biopsy. In addition to DH, he was found to have Pneumocystis jiroveci pneumonia and multi-resistant Salmonella choleraesuis bacteraemia. He improved with treatment with antibiotics and was commenced on conventional itraconazole, orally. Antiretroviral therapy was commenced soon after. He was unable to achieve therapeutic levels with the conventional formulation due to gastrointestinal side effects and had ongoing fevers. A newer formulation of oral itraconazole with improved bioavailability was commenced. He achieved therapeutic drug levels and had no further intolerance. His fevers settled and the rash improved. He has now completed one year of treatment and is well. To our knowledge this is the first case of moderate DH in an advanced HIV patient treated successfully with oral itraconazole with improved bioavailability.