Histoplasma capsulatum Infectious Agent Diagnosis Fungal Yeast within

Histoplasma capsulatum Infectious Agent Diagnosis • Fungal Yeast within human • Intracellular replication Epidemiology & Risk Groups • Found worldwide in river valleys • Immunocompromised host (especially patients with AIDS or on immunosuppressants • People who go into caves • 250, 000 case in US / year • Blood cultures to rule out dissemination • Antigen detection to rule out tuberculosis, sarcoidosis, B. dermatitidis, C. immititis • Growth on Sabouraud’s Agar will cause hyphae Treatment • Anti-fungal medications • Itraconazole or amphotericin B • Surgery is required to remove brocholithiasis Transmission Virulence Factors • Inhaled conidia and mycelial fragments from soil, growth enhanced by bat/bird feces • No person-to-person transmission • Inhibition of phagolysosomal destruction, replication occurs here • Raising the p. H of phagolysosomal compartments 3 -14 days - Pathogenesis Incubation period Intracellular conversion from mycelial form to yeast form. Yeast continue to replicate within phagosomes of macrophages 1 -2 weeks - Yeast growth stops due to developing immune response a Weeks – - Development of calcified fibrinous granulomas with areas 24 months of caseous necrosis Death - Can spread through blood, but is very rare, causing systemic symptoms - If untreated death from pulmonary fibrosis pulmonary and cardiac failure Symptoms • 90% asymptomatic • Fever, myalgia, severe dysnea sometimes with blood, rales and wheezing, hepatosplenomegaly • If treated, long recovery time, but good prognosis. • If untreated, abroncholithiasis + stone expectoration can occur • Very rare, even in immunocompromised host, meningitis, endocarditis, pericarditis, • Death from pulmonary fibrosis leading to pulmonary and cardiac failure These icons were found on the Noun Project: Microscope: Created by Dumitriu Robert, Globe by Tinashe Mugayi, Mosquito: Created by Edward Boatman, Bacteria: Created by Maxim Kulikov, Person: Created by Hayashi Fumihiro, Disease: Created by nayeli zimmerman, Rare Disease: Created by Heads. Of. Birds, Syringe and Medicine: Created by Sergey Demushkin