Cerebral phaeohyphomycosis caused by Scytalidium dimidiatum: a case report from India.

We report a case of cerebral phaeohyphomycosis caused by Scytalidium dimidiatum (synanamorph Nattrassia mangiferae) in a young, apparently immunocompetent Indian male. Etiological diagnosis was made by recovery of the fungus in culture and histopathological examination. The infection proved fatal despite aggressive antifungal therapy.

Characterization of human immunodeficiency virus (HIV)-infected cells in infiltrates associated with CNS opportunistic infections in patients with HIV clade C infection.

Infection with human immunodeficiency virus (HIV) clade C is the most common HIV infection worldwide, yet its impact on the nervous system remains largely unknown. Autopsy studies from regions affected by this virus are scarce, and HIV dementia has only rarely been reported from these countries. Most patients who develop neurologic complications die of opportunistic infections. We thus conducted a neuropathologic study from a single institution in India to characterize the HIV-infected cells in the inflammatory infiltrates in a total of 15 cases (5 patients each who died of either CNS toxoplasmosis, tuberculosis, or cryptococcal meningitis). Nearly, all patients had HIV-infected cells in the brain, although these cells were most abundant in patients with toxoplasma encephalitis. Interestingly, none of the patients had any multinucleated giant cells. HIV-infected cells were found in the parenchyma, perivascular regions, and choroid plexus and found infiltrating the parenchyma from the meninges, suggesting multiple portals of entry into the brain. These findings suggest the possibility that patients, even if successfully treated for an opportunistic inflection, may be at high risk of developing HIV encephalitis and subsequent dementia.

Cysticercal chronic basal arachnoiditis with infarcts, mimicking tuberculous pathology in endemic areas.

Neurocysticercosis (NCC) is the most common of the parasitic diseases affecting the CNS, with protean clinical manifestations. Stroke as a complication of NCC occurs in a very small percentage of cases, mostly involving small perforating vessels while major intracranial vessel involvement is extremely rare. The present report involves two autopsied cases of chronic cysticercal basal arachnoiditis causing large arterial territory infarcts and, in the second case, a hypothalamic mass. They were diagnosed and managed, clinically and by neuroimaging, as stroke and neurotuberculosis, respectively. The diagnosis was established only at autopsy, which revealed NCC causing basal arachnoiditis, major vessel vasculitis and infarcts. Histologically, case 1 showed degenerating racemose cysticercal cyst within the thick basal exudate. In the second case, remnants of the degenerated cysticercal cyst in the form of hooklets and calcareous corpuscles were identified within the giant cell inciting a granulomatous response to form a hypothalamic mass lesion mimicking tuberculoma. The present case report highlights the importance of considering the non-tuberculous etiologies of chronic basal arachnoiditis like NCC before initiating therapy especially in countries endemic to both NCC and tuberculosis, like India.

A rare case of cellular schwannoma involving the trigeminal ganglion.

Cellular schwannomas rarely involve the cranial nerves, being more common in the spinal and peripheral nerves. A rare case of cellular schwannoma involving the gasserian ganglion, a hitherto unreported site, that extended infratentorially to present as a cerebellopontine angle tumor is reported. It is important to recognize that cellular schwannomas can histologically mimic malignant peripheral nerve sheath tumors because of their high cellularity and mitotic activity, but they are relatively benign tumors with a tendency to recur but not metastasize.