Beriberi neuropathy. Morphometric study of sural nerve

Seven biopsied sural nerves from patients with beriberi were morphometrically evaluated. In teased fiber analysis the mean frequency of myelinated fibers showing axonal degeneration and segmental demyelination was 37.5 and 5.3%, respectively. In two cases with frequency of segmental demyelination higher than 5%, segmental demyelination was shown by statistical criteria to have occurred on certain fibers in a clustered fashion. Therefore, the segmental demyelination in beriberi may be secondary to axonal degeneration. Electromyographic findings and slow improvement of muscle weakness were compatible with axonal degeneration of motor fibers. Determinations of fiber densities revealed preferential decrease of the density of large myelinated fibers with the preservation of the density of small myelinated and unmyelinated fibers. The preferential nerve fiber involvement in beriberi was not associated with pain in the lower limbs and this fact is contrary to the expectation of the proponents of the gate control theory.

Deep tendon reflex in Eaton-Lambert syndrome

The mechanism of absent or decreased deep tendon reflex in Eaton-Lambert syndrome was studied. There was no evidence suggestive of the presence of a neuropathy. On the other hand, a brief (about 10 seconds) maximal voluntary contraction made the absent deep tendon reflexes elicitable, which suggests that the block of neuromuscular transmission in Eaton-Lambert syndrome is responsible for the absent or decreased deep tendon reflex. Such enhancement of the decreased deep tendon reflex in Eaton-Lambert syndrome might be helpful in differentiating neuropathy and Eaton-Lambert syndrome.

Oculopharyngeal myopathy with distal and cardiomyopathy

Two patients are described with distinctive clinical features including an insidious onset, slow progression, bilateral ptosis, weakness of facial muscles, dysphagia, muscle atrophy, and weakness with a distal distribution in the extremities, and cardiomopathy with conduction system disorders. Electromyographic studies and muscle biopsy showed features highly suggestive of a myopathic disorder. One case is considered to be sporadic. The other seems to be a familial disorder, because of the presence of a mild atrioventricular block and right incomplete bundle branch block in the patient's son and the presence of eyelid ptosis in his sister. This may be a variant of oculopharyngeal myopathy with distal and cardiomyopathy. It will be necessary to perform long-term follow-up studies in these families.

A case of gamma heavy chain disease associated with autoimmune haemolytic anaemia: clinical, haematological, immunological and pathological details

A 76-year-old Japanese man, presented with a case of gamma heavy chain disease associated with autoimmune haemolytic anaemia. The clinical course progressed rapidly, accompanied by fever, lymphadenopathy, erythematous palate and hepatosplenomegaly. As the disease progressed, haemoglobin level gradually reduced, and jaundice occurred. A complication of autoimmune haemolytic anaemia was deduced from the laboratory data obtained at this time. The patient's serum and urine contained an M-component with electrophoretic and antigenic properties resembling those of the Fc-fragment of G1 globulin. Microscopic and electron microscopic findings on the tumor cells infiltrating in lymphnodes indicated all types of transitional forms from small lymphocytes to large lymphoplasmoblastic cells.

Studies of sensory conductions. Comparison of latencies of orthodromic and antidromic sensory potentials

Latencies of orthodromic and antidromic sensory potentials were compared in 16 normal median nerves. Peak latency was longer in the antidromic sensory response in every case. The peak latency of the antidromic sensory response depended on the distance between the recording electrodes; with shorter interelectrode distances it was similar to that of orthodromic sensory response.