Unilateral optic neuritis caused by Histoplasma capsulatum in a patient with the acquired immunodeficiency syndrome.

PURPOSE: To evaluate the potential of Histoplasma capsulatum to cause optic neuritis in the setting of the acquired immunodeficiency syndrome (AIDS).

METHODS

We examined a 35-year-old man with a history of AIDS and disseminated histoplasmosis who developed a unilateral progressive optic neuritis of enigmatic origin. An optic nerve sheath biopsy was performed to provide a tissue diagnosis.

RESULTS

Histoplasma capsulatum was identified in both the optic nerve sheath and fungal culture.

CONCLUSION

Histoplasma capsulatum should be considered in the differential diagnosis of optic neuritis in patients with AIDS, even in the absence of chorioretinal findings.