Histoplasmosis
[Lancet Infect Dis 2021;21:e364-74]
Usual Pathogen
Histoplasma capsulatum
- Histoplasma capsulatum found in soil contaminated with bat guano or bird excreta.
- Global distribution but highly endemic along St. Lawrence, Mississippi and Ohio river basins as well as Central America/Caribbean regions.
- Causes CNS (chronic meningitis and/or brain lesions), mediastinal, pericarditis, pulmonary and progressive disseminated (skin, GIT) infections.
- Fluconazole less effective than itraconazole against Histoplasma spp. Echinocandins are not effective.
- Infectious Diseases consult recommended.
Central Nervous System (CNS)
| Empiric Therapy | Duration | |
|---|---|---|
|
Induction therapy: |
||
| Amphotericin B, liposomal | 5mg/kg IV daily | 4-6 weeks |
| Maintenance therapy: | ||
| Itraconazole | 200mg PO bid or tid |
At least 12 months and resolution of CSF abnormalities (6 months in non-immunosuppressed patients depending on site and severity of infection) |
Pulmonary
Acute pulmonary
Mild-moderate
Immunocompetent, symptoms less than 1 month
– no treatment recommended.
Immunocompromised or symptoms greater than 1 month
| Empiric Therapy | Duration | |
|---|---|---|
| Itraconazole | 200mg PO tid | 3 days |
| then | ||
| Itraconazole | 200mg PO bid |
6-12 weeks |
Severe
| Empiric Therapy | Duration | |
|---|---|---|
| Amphotericin B, liposomal | 3-5mg/kg IV daily | 1-2 weeks |
| then | ||
| Itraconazole | 200mg PO tid |
3 days |
| then |
|
|
| Itraconazole | 200mg PO bid |
6-12 months |
Chronic pulmonary
| Empiric Therapy | Duration | |
|---|---|---|
| Itraconazole | 200mg PO tid | 3 days |
| then | ||
| Itraconazole | 200mg PO bid |
12-24 months |
Progressive disseminated (e.g. skin, GIT)
Mild-moderate
| Empiric Therapy | Duration | |
|---|---|---|
| Itraconazole | 200mg PO tid | 3 days |
| then | ||
| Itraconazole | 200mg PO bid |
For at least 12 months |
Severe
| Empiric Therapy | Duration | |
|---|---|---|
| Amphotericin B, liposomal | 3mg/kg IV daily | 2 weeks |
| then | ||
| Itraconazole | 200mg PO tid |
3 days |
| then |
|
|
| Itraconazole | 200mg PO bid |
For at least 12 months |