Catastrophic visual loss due to Cryptococcus neoformans meningitis

We have reviewed our experience with 17 of our own patients with cryptococcal meningitis and 32 cases from the literature. Although this complication is an uncommon event, patients with cryptococcal meningitis may develop visual loss in the absence of other ocular lesions (endophthalmitis or cryptococcomas in the visual pathway) that could explain the visual symptoms. There are 2 distinct patterns of visual loss: rapid visual loss and slow visual loss. Rapid visual loss is characterized by onset of profound visual loss over a period as short as 12 hours before or early in the course of therapy and a clinical syndrome that is strongly suggestive of optic neuritis. Direct invasion of the optic nerve by C. neoformans is demonstrated by cases in this and other reports. Slow visual loss is characterized by slow but progressive visual loss which typically begins later during therapy and may be due to the effects of increased intracranial pressure. While the initial deficit may be mild, patients with slow visual loss can progress to severe visual loss over weeks to months. The only factors that appear to predict either pattern of visual loss are the presence of papilledema, an elevated CSF opening pressure, and a positive CSF India ink preparation. In the 25 visual loss patients for whom data were available for all 3 items, 10 (40%) were positive for all 3, as opposed to only 4 of 114 (3.5%) from a reference group of cryptococcal meningitis patients without visual loss (p < 0.00001). The only therapeutic measures with any degree of consistent success were those directed at reducing intracranial pressure. When begun early and used aggressively, such therapy halted and sometimes even reversed the course of visual loss, particularly in the slow visual loss group. Corticosteroids did not appear to be of value in the small number of patients who received them.