Epidemiological study of myasthenia gravis in the province of Reggio Emilia, Italy.

We carried out a retrospective incidence, prevalence and mortality survey of myasthenia gravis in the province of Reggio Emilia in Northern Italy. Based on 49 patients, the mean incidence per year for the period 1980 through 1994 was 7.8 per 1,000,000. On 31 December 1994 the prevalence rate was 117.5 per 1,000,000 for all patients, either active or recovered (50 cases in a population of 427,493) and 103.4 per 1,000,000 for the active disease. In the 15-year period 1980-1994 the average mortality rate was 1.0 per 1,000,000 per year. The average age at onset was 44.6 +/- 21.0, and the average age at the time of prevalence determination was 51.1 +/- 19.6 for the active disease. At the time of diagnosis, 21 patients (36.8%) were classed in group I according to Osserman's criteria, 31 in group II (54.4%), (19 in group II-A and 12 in group II-B), and the other 5 (8.8%) in group III. Of all the prevalence cases, 6 (12%) were in remission without therapy and 6 with therapy, while most of the others 16 (32%) were classed in group I, 15 (30%) in group II, and 1 (2%) in group III. Thymectomy was performed in 20 patients (35.1%), 12 (21%) had thymoma (malignant in 4 cases), 6 had thymic hyperplasia while in two patients thymic histology was normal. The relation the grade of Osserman's scale at the time of incidence and the presence of thymoma were significant. Higher grades of Osserman's scale were associated were malignant thymoma. Furthermore the relationship between thymectomy and the grade of Osserman's scale at the date of prevalence was significant for the presence of lower grades of Osserman's scale in the patients submitted to thymectomy.

Juvenile Leigh syndrome with protracted course presenting as chronic sensory motor neuropathy, ataxia, deafness and retinitis pigmentosa: a clinicopathological report.

We herein describe a male patient who died at 37 years of age, after having suffered from a slowly progressive syndrome of chronic sensory motor neuropathy, deafness, retinitis pigmentosa and ataxia. The neuropathological study showed symmetric areas of necrosis and demyelination affecting the cerebellum and brainstem. The type of lesion was consistent with the characteristics of Leigh Syndrome. On the basis of the histology of the lesions, we believe that they appeared only a few months before the death of the patient. We underline the atypical clinical picture and suggest that, in certain cases, brain MRI may not be a reliable diagnostic tool.

Lead, cadmium, and selenium in the blood of patients with sporadic amyotrophic lateral sclerosis.

We determined whole blood lead and cadmium levels, and serum selenium levels in patients with sporadic amyotrophic lateral sclerosis and age- and sex-matched controls. Disability due to the disease directly correlated with lead levels, and there was a strong inverse correlation with selenium concentrations. Lead and selenium concentrations tended to be similar in the cases and controls, both in the study population as a whole and after the removal from the analysis of the patients with the highest degree of disability. In the patients with limited disability, cadmium concentrations were higher than in the controls. Our findings lend limited support to a possible involvement of cadmium, but not lead, in the etiology of sporadic amyotrophic lateral sclerosis, and strongly suggest that short-term indicators of exposure are inadequate to investigate the relationship between selenium and the disease.

X-linked bulbar and spinal muscular atrophy, or Kennedy disease: clinical, neurophysiological, neuropathological, neuropsychological and molecular study of a large family.

We report the clinical, neurophysiological, neuropsychological, neuropathological and molecular findings in a large family with X-linked bulbar and spinal muscular atrophy (X-BSMA). Molecular study, performed in 28 family members, showed an increase in the number of CAG repeats in 6 affected males (including 2 presymptomatic patients), and in 10 females, of whom 5 were obligate carriers. All symptomatic patients showed, besides the typical manifestation of X-BSMA, neurophysiological signs of sensory nerve involvement, and abnormal findings in neuropsychological tests. Sural nerve biopsy, performed in two patients, was consistent with axonal atrophy and slow-rate degeneration, with secondary demyelination. Neurophysiological alterations were also present in 6 out of 8 carriers, consisting of neurogenic EMG changes in 3 cases and abnormal sensory action potentials (SAP) and reduced conduction velocity of the sural nerve in 3 cases. Abnormalities of at last two neuropsychological tests were found in 6 out of 8 carriers. Alterations of the sensory nerves in X-BSMA patients have been previously reported in some cases; however, we demonstrate for the first time sensory nerve involvement also in carriers. Evidence of central nervous system involvement, with neuropsychological impairment in all symptomatic patients and in some carriers, is another feature of this family, not previously reported in X-BSMA. In spite of the variable phenotypic features, the number of CAG repeats ranged from 40 to 44 in the affected patients, indicating that phenotypic expression was not related to the size of the mutation, but was probably age-related.

Epidemiological survey of amyotrophic lateral sclerosis in the province of Reggio Emilia, Italy: influence of environmental exposure to lead.

We carried out a retrospective incidence, prevalence and mortality survey of amyotrophic lateral sclerosis (ALS) in the province of Reggio Emilia, northern Italy. Based on 79 patients, the mean incidence per year for the period 1980 through 1992 was 1.5 cases per 100,000. On December 31st, 1992, the prevalence rate was 5.4 per 100,000. In the 10-year period of 1983-1992 the average mortality rate was 1.3 per 100,000 per year. The average age at onset was 61.3 +/- 10.2, the average survival period thereafter was 26.3 months +/- 17.7; 27.3 +/- 17.6 for classic ALS, 19.5 +/- 8.4 for progressive bulbar palsy and 36.3 +/- 41.4 for pseudopolyneuritic ALS. The incidence rate, recorded in public health district No.12, an area with documented lead pollution since the 1970s, was standardized to the sex and age of the population of the province. Its incidence and prevalence rate were comparable to the rates found in the remaining area of the province.

Epidemiological survey of multiple sclerosis in the provinces of Reggio Emilia and Modena, Italy.

We present the results of an epidemiological survey on MS conducted in the provinces of Reggio Emilia and Modena (4,980 km2) from 1970 to 1990. The population increased from 943,182 residents in 1970 to 1,024,223 in 1990, with an average population during the period of the survey of 993,056. The mean annual incidence was 1.59 cases/100,000 inhabitants (c.i. 95% 1.42-1.78). The prevalence as of December 31, 1990, was 39.44/100,000 inhabitants. Our study is a further demonstration that Italy is a high-risk zone for this disease, and also demonstrates the possibility of carrying out reliable epidemiological surveys even over extensive territories.

Kennedy disease in an Italian kindred.

An X-linked adult-onset neurogenic muscular atrophy, chiefly proximal, with late involvement of the distal musculature and medulla oblongata was present in 4 members of a single kindred. Associated in all patients were gynecomastia, impotence and essential tremor. Frederickson type IV hyperlipemia was present in 1 patient. Hormonal stimulation tests in 2 patients elicited a borderline low testicular response in the younger of the 2 and a pathological response in the older patient. On the evidence of these and previously reported cases, Kennedy disease would appear to be characterized by an X-linked proximal neurogenic amyotrophy of adult onset and by a testicular endocrine deficit.