The retinal diagnosis is ocular histoplasmosis. The patient shows the three classic features of this disease, peripapillary atrophy, evidence of subfoveal choroidal neovascular membrane, and peripheral RPE changes. These RPE changes can assume the form of punched out "histo spots", of whiche only a few which were present, or the form of atropic RPE changes that can be linear in shape. Additional tests that could be done to confirm the diagnosis are the histoplasmin skin test and a chest X-ray to look for calcifications in the lungs. Neither test was done since the clinical diagnosis was firm and there are reports that dispute the specificity of the histoplasmin skin test and the chest X-ray.

Management was to provide the patient with the correct diagnosis and to communicate that while many patients with ocular histoplasmosis retain good vision in at lease one eye, there is an increased risk for a CNVM in the left eye. Patients should be given an Amsler grid and followed annually.

In histoplasmosis the CNVM generally grows between the RPE and retina and surgical removal has a higher success rate than with an age-related CNVM which grows below and within the RPE layer. The Macular Photocoagulation Study found that laser treatment for a subfoveal CNVM in hitoplasmosis is not beneficial. Histoplasmosis is caused by the fungus Histoplasma capsulatum and is acquired by breathing in bat or bird guano. It is a chronic systemic disease that, besides the lungs and eyes, can affect most other organs of the body and, while most common in the Mississipi and Ohio River Basin, is found world wide. The disease can reactivate as an opportunistic infection in immunocompromised patients and active disease is treated with antifungals.