Yasha Tc

Giant serpentine aneurysm of vertebrobasilar artery mimicking dolichoectasia : an unusual complication of pediatric AIDS

Central nervous system manifestations of acquired immunodeficiency syndrome (AIDS) in children differ strikingly from adults. Developmental delay, subacute AIDS encephalitis and basal ganglia calcification are common in children, in contrast to opportunistic infections and dementia in adults. Intracranial aneurysms are being recognized with increasing frequency in pediatric AIDS. Fusiform dilatation of vessels of circle of Willis to form large aneurysms, termed cerebral aneurysmal childhood arteriopathy, is an exceedingly rare complication of pediatric AIDS. We report a case of massive fusiform dilatation of vertebrobasilar system mimicking congenital dolichoectasia with evidence suggesting direct causation by HIV-1 Clade C virus. In view of scant literature that exists on this unusual complication of pediatric AIDS, we present a detailed review of all previously recorded cases and review the etiopathogenesis. There are 20 reports (32 cases) on record till date that have mostly involved the anterior circulation, occurring between 4-15 years of age. Occurrence is associated with profound immunosuppression, and perinatally acquired HIV with latent interval of 5.5-11 years to onset of symptoms. Direct causation by HIV is favored as reports demonstrate presence of virus in affected vessels, association with high viral load and, more conclusively, arrest in progression or reversal with early initiation of highly active antiretroviral therapy (HAART). The fusiform nature and location of these aneurysms makes any form of surgical intervention or embolization impossible. High degree of clinical suspicion and awareness of this entity is, therefore, important as this can place young patients at risk for major cerebrovascular accidents.

Pathobiology of fungal infections of the central nervous system with special reference to the Indian scenario

Ubiquitously present fungi in the environment find a nidus in the human body and adopt its metabolic machinery to be in symbiosis or become pathogenic. Immunocompromised states like human immunodeficiency virus (HIV) / acquired immunodeficiency syndrome (AIDS), systemic neoplasia and organ transplantation have enhanced the frequency of fungal infections. High-risk behavior, IV drug abuse and air travel have led to the emergence of new fungal infections hitherto geographically localized. The pathology in the central nervous system (CNS) is dictated largely by the size of the fungus - the yeast forms, by virtue of their small size enter the microcirculation to cause meningitis and microabscesses, while hyphal forms invade the vasculature to manifest as large pale or hemorrhagic infarcts. The growth kinetics of fungi, the antigenic character of the capsule. the proteases secreted by the mycelial forms and the biochemical milieu in the host also determine clinical manifestations. A hospital-based analysis of the available information from India suggests that in the non-HIV patient population, hyphal forms like Aspergillosis and Zygomycosis are the most common pathogens, while yeast forms like Cryptococcus and Candida are the prime pathogens in cases of HIV/AIDS, the altered macrophage function acting in synergy with suppressed cell-mediated immunity. In Northeastern states, systemic infection by Penicillium marneffei is reported in association with HIV though CNS involvement is not recorded. Although fungal infections of the CNS are reported from various hospitals in India, studies are limited by non-availability of relevant microbiological studies and the reported prevalence data is biased by the surgical practices, availability of postmortem and microbiology and laboratory support. Detailed clinical and mycological investigations related to the interaction between the fungus and host environment is a fertile area of research to understand the basic pathogenetic mechanisms.

Pathology of Madras type of motor neuron disease (MMND) – a histological and immunohistochemical study

Abstract A neuropathological report of Madras type of motor neuron disease (MMND) is presented and the differences from other forms of MND are discussed. An 18-year-old girl presented with nerve deafness and slowly progressive bulbo-spinal muscular atrophy, characteristic of MMND. Post-mortem examination of the spinal cord showed a severe loss of anterior horn cells, prominent dilatation of vessels, diffuse, but sparse sprinkling of microglial cells and lymphocytes, and demyelination and sclerosis of the ventrolateral columns. Neuronal depletion and marked gliosis was noted in the cochlear nucleus on both sides, while other bulbar motor nuclei were also involved. The cochlear nerve showed demyelination and axonal loss. Trigeminal and vestibular ganglia revealed features of ganglionitis. The possibility of an inflammatory aetiology for MMND needs to be considered.

A variant form of mucolipidosis IV: report on 4 patients from the Indian subcontinent.

The clinical manifestations and histopathologic and neuroimaging findings in 4 Indian patients with a variant form of mucolipidosis IV are described. The presenting symptoms were psychomotor delay, spastic paraplegia, and mild mental retardation. One patient also had visual deterioration due to optic atrophy. None had corneal or retinal abnormalities. Magnetic resonance imaging in 3 patients showed a uniformly thin corpus callosum in all patients and white matter changes in 2 patients. Electron microscopic examination of skin biopsy specimens revealed storage bodies characteristic of mucolipidosis IV. These patients differ from previously described patients with this disorder in the absence of corneal abnormalities and in their presentation with spastic paraplegia during the second decade of life. Correct diagnosis is needed for genetic counseling, prognostication. and reduction of additional familial burden of this rare disease.

Optic nerve axonal pathology is related to abnormal visual evoked responses in AIDS

Electrophysiological studies in subjects with HIV/AIDS demonstrate subtle changes in the visual pathway even in the absence of visual symptoms. But the pathological correlate of the electrophysiological abnormalities is largely unknown. This study attempts to correlate pathological changes in the retina and intraorbital portion of optic nerve in four drug naïve patients of AIDS caused by HIV-1 clade C, who had abnormalities in the visual evoked potentials recorded antemortem. Three had no visual complaints and one patient had sudden loss of vision in the right eye. In all four patients, the visual evoked potentials disclosed variable prolongation of P100 latencies. Histologically axonal cytoskeletal breakdown and depletion in the optic nerves was the cardinal finding with variable myelin loss, even in the absence of overt visual dysfunction, or infective retinitis. The axonal loss was maximal in the symptomatic case. Retinal ganglion cell depletion was seen in only two patients. Sectoral infiltration of the optic nerve by cryptococci and Cryptococcal choroiditis was the only opportunistic infection to involve the eye. Axonal pathology in the optic nerve appears to be related to the abnormalities recorded in visual evoked potentials even in the absence of overt clinical symptoms. Opportunistic infections could be contributing to the axonal pathology in the optic nerve in patients with AIDS.

Cholesterol Ester Storage Disease With Unusual Neurological Manifestations in Two Siblings : A Report From South India

Cholesterol ester storage disease is a rare autosomal recessive storage disorder resulting from lysosomal acid lipase deficiency. Two siblings manifested with hepatosplenomegaly, ptosis, and bilateral external ophthalmoplegia. Evaluation revealed hyperlipidemia and bilateral adrenal calcifications. Leukocyte acid lipase levels were significantly low in both the patients, compared with controls, suggesting a diagnosis of cholesterol ester storage disease. Ptosis and external ophthalmoplegia have hitherto not been reported in cholesterol ester storage disease.

Late onset glycogen storage disease type II with reducing body-like inclusions.

Skeletal muscle tissue from 3 patients with clinical diagnosis of limb girdle muscular dystrophy revealed a vacuolar myopathy with glycogen storage and lysosomal activity. A diagnosis of late onset GSD Type II was considered. An interesting finding was the presence of round to oval eosinophilic inclusions which reduced on menadione linked a-glycerophosphate dehydrogenase (MAG). There are only two reports in the literature describing similar inclusions in late onset GSD II. We report morphological findings of this rare disorder and compare the findings with earlier two reports.