SMON as seen from Bombay.

Clioquinol is still consumed in India in considerable amounts but no new case reports have appeared since 1977. A review is made for a regional neurotoxicology group of an enquiry that we conducted in Bombay to gather information regarding SMON, spanning the period of 1967 to 1976. Nine patients were diagnosed with a variable degree of confidence as suffering from SMON, two from a retrospective search and seven after a prospective watch for the disease. Myelopathy with predominant more distal dysesthesia was seen more often than the full-blown picture of SMON. The peripheral neuropathy component (N) diagnosed clinically or electrophysiologically was seen only once. Pyramidal tract disturbances and resulting spasticity was as striking as posterior column disorder and sensory ataxia. Subacute myelopathy was seen in six patients, optico-myelopathy in two, and myeloneuropathy only once. It was clear that clioquinol has potential neurotoxicity, but no definitive explanation was forthcoming about the vast difference in the prevalence of SMON as reported from Japan and seen by us in Bombay.

Interrelationships between the B-vitamins in B12-deficiency neuromyelopathy. A possible malabsorption-malnutrition syndrome.

Five patients presenting clinically with a form B12-deficiency neuromyelopathy, with cord involvement in all and proximal muscle weakness in two of them, were investigated for their neurologic, hematologic and vitamin status. Megaloblastosis and achlorhydria were present in all, and impaired absorption of 57Co vitamin B12 and of D-xylose was detected in four. Total cyanide extracted vitamin B12 (A) was lowered in all cases and noncyanide extractable (B) in four of the five, being zero in three. All five responded to injections of hydroxocobalamin. In two patients sequential estimations showed that both A and B, especially the latter, rose steeply initially, normalizing at 50% of A after some weeks. Moiety B is suggested to be physiologically the more active and dissociable form of vitamin B12. Markedly elevated initial serum folate levels, and their subsequent fall under treatment with B12, indicated the operation of the "methyltetrahydrofolate trap". Blood levels of thiamin, nicotinic acid and pantothenic acid were within normal limits. However, serum riboflavin (B2) total vitamin B6 and pyridoxal were reduced in all where tested. Vitamin B6 deficiency could have resulted from its own malabsorption and have contributed to be B12 deficiency. Vitamin B2 and B6 levels also corrected themselves on B12 therapy. The B-vitamin deficiencies in our patients probably resulted from intestinal malabsorption, with a possible factor of malnutrition consequent to their strictly vegetarian diet.

Prevalence of multiple sclerosis in the Parsis of Bombay.

We carried out a door-to-door-survey to screen a community of 14,010 people (Parsis living in colonies in Bombay, India) for possible neurologic diseases, and used defined diagnostic criteria to evaluate people who tested positive on the screening survey. There were three clinically definite cases of multiple sclerosis (21/100,000). This is the first prevalence survey for multiple sclerosis in a large developing country.

Radiation necrosis causing failure of automatic ventilation during sleep with central sleep apnea.

A patient operated upon for a midline cerebellar hemangioblastoma developed failure of automatic respiration during sleep, together with central sleep apnea syndrome, approximately two years after receiving radiation therapy to the brain. Clinical and CT scan findings were compatible with a diagnosis of radiation necrosis as the cause of his abnormal respiratory control.

Profile of multiple sclerosis in the bombay region. On the basis of critical clinical appraisal.

Using internationally accepted strict clinical criteria, 30 patients with probable multiple sclerosis (MS) fron the Bombay region have been described. They were personally studied and followed up over a period of 15 years. In addition, 9 patients with neuromyelitis optica and 6 with a mixed neurological picture of MS and neuromyelitis optica have been described. As in Japan, the neuromyelitis optica type of presentation was relatively more frequent in our material than in the West. In this small series MS was more frequent in patients with a better socio-economic status, in the Parsee community and in patients with a fair complexion, whereas neuromyelitis optica was more frequent in patients with poor socio-economic status. A relatively high proportion of patients (nearly half of the MS patients with optic nerve involvement and two-thirds of the MS--neuromyelitis optica group) had bilateral optic nerve involvement. Except in 2 patients, the tempo and course of the disease in our patients with MS was comparable to that seen in the West. In 3 patients with MS the initiation of symptoms or appearance of fresh symptoms was related to vaccination. In addition to the above 45 patients, 29 other cases of possible demyelination have been reviewed. Nine of these had one or more remission and relapse but in the same site as the first episode. Seventeen had a solitary episode of spinal cord or brainstem disturbance with some remission and 3 had multiple lesions but without remission or clear dissemination in time. In the absence of a specific diagnostic test or autopsy, such atypical cases will remain unclassified. To conclude, MS does occur in the Bombya region and elsewhere in India but the incidence is much less than in the West. Further studies and especially careful follow-up of atypical cases may show that the prevalence is higher than it seems today.

Proposal of diagnostic criteria for human cysticercosis and neurocysticercosis.

Taenia solium cysticercosis is a major public health problem in several areas of the world. While the disease has a recognized etiologic agent, its definitive histological diagnosis is not possible in most cases because this parasite tends to lodge in cerebral tissues where routine biopsy is not feasible. Therefore, the diagnosis of human cysticercosis (and neurocysticercosis) should rest on the proper interpretation of the patients' symptoms together with data provided by radiological studies and immunologic tests for the detection of anticysticercal antibodies. Unfortunately, the pleomorphism of this parasitic disease creates confusion when non-specific clinical, radiological, or immunologic criteria alone are used to detect cases among populations or to diagnose hospitalized patients with neurological manifestations. We propose a chart of diagnostic criteria for human cysticercosis that objectively permit clinicians and health care workers to evaluate clinical, radiological, immunologic, and epidemiologic data of patients. The chart uses four degrees of criteria: absolute, major, minor, and epidemiologic, that were selected on the basis of their individual diagnostic strength. Interpretation of such criteria will result in three categories of diagnostic certainty: definitive, probable and possible, according to the likelihood that cysticercosis is present in a given person.