Clinical course of a cohort in the Cuban epidemic optic and peripheral neuropathy

Cuban epidemic optic neuropathy and its relationship to toxic and hereditary optic neuropathy

The similarities and differences between toxic/nutritional and hereditary optic neuropathy and the pathophysiologic mechanisms that they have in common are described. This is based on data from the epidemic suffered in Cuba in 1992, which affected the optic nerves of many individuals and the experience of the authors in dealing with various toxic optic neuropathies, as well as Leber's hereditary optic neuropathy.

Chapter 50: history of tropical neurology

Tropical neurology began less than two centuries ago. Consumption of dietary toxins predominated at the beginning and gave birth to the geographic entity. The story moved from lathyrism through Jamaican neuropathy to cassava-induced epidemic neuropathy, which was contrasted with Konzo, also associated with cassava. Other tropical diseases enumerated with chronological details include: Chaga's diseases, kwashiorkor, Madras type of motor neuron disease, atlanto-axial dislocation, Burkitt's lymphoma and Kuru, associated with cannibalism among the Fore linguistic group in New Guinea. More recent documentation includes the Cuban neuropathy in 1991 with an epidemic of visual loss and neuropathy, Anaphe venata entomophagy in Nigeria presenting as seasonal ataxia, and neurological aspects of the human immunodeficiency virus infection complete the picture. With time, professional associations were formed and the pioneers were given prominence. The World Federation of Neurology featured Geographic Neurology as a theme in 1977 and Tropical Neurology was given prominence at its 1989 meeting in New Delhi, India. The situation remains unchanged with regards to rare diseases like Meniere's, multiple sclerosis, hereditary disorders. However, with westernization and continued urbanization, changing disease patterns are being observed and tropical neurology may depart from dietary toxins to more western world-type disorders.

Supportive Therapie und Palliativmedizin bei Patienten mit malignen Gliomen

The primary aim of supportive care in patients with malignant gliomas is accurate symptom control in order to optimize quality of life. The palliative approach should be considered from the beginning of treatment, due to the intractable and incurable character of the disease. Neurological signs and symptoms have to be investigated clinically, as well as neuroradiologically in order to evaluate treatment response and to provide adequate supportive care.

High mortality of subjects with endemic ataxic polyneuropathy in Nigeria

BACKGROUND

Endemic ataxic polyneuropathy, a neurological syndrome that was thought to be benign, has been shown to persist in some communities in south-western Nigeria, where it was first described in the 1950s.

OBJECTIVES

This study was conducted to compare mortality of cases and controls, and to determine if mortality is related to exposure to cyanide from cassava foods.

MATERIAL AND METHODS

Cases of endemic ataxic polyneuropathy and two groups of controls, one group living in an endemic community and the other group living in a non-endemic community, were followed for 25 months. The outcome was death from medical causes.

RESULTS

A total of 5970 subjects, 204 cases and 5766 controls - 4000 controls in the endemic community and 1766 controls in the non-endemic community, were followed. A total of 153 subjects died, 24 cases, 115 controls in the endemic community, and 14 controls in the non-endemic community. Relative risks of death (95% CI), adjusted for age and gender, were 4.5 (2.3-8.9) for cases (P < 0.0001), but 2.6 (1.5-4.6) for controls living in the endemic community (P = 0.001).

CONCLUSION

This study shows that endemic ataxic polyneuropathy decreases survival. The finding of lower risk of death in the community with higher exposure to cyanide from cassava foods indicates that mortality of endemic ataxic polyneuropathy is not associated with exposure to cyanide from cassava foods.

Neuromuscular diseases and disorders of the alimentary system

This review outlines the relationship and interaction between neuromuscular diseases and disorders of the alimentary system. Neuromuscular manifestations of gastrointestinal and hepatobiliary diseases are first considered. Such diseases may cause neuromuscular disorders by leading to nutritional deficiency or by more direct mechanisms. The pathogenesis, clinical features, and treatment of these various neuromuscular manifestations are discussed. The impact of disorders of nerve, neuromuscular transmission, and muscle on the alimentary system is then reviewed. The main sequelae are impaired deglutition and gastrointestinal dysmotility. The management of these complications is considered.

Persistence of tropical ataxic neuropathy in a Nigerian community

OBJECTIVES

The term tropical ataxic neuropathy (TAN) is currently used to describe several neurological syndromes attributed to toxiconutritional causes. However, TAN was initially proposed to describe a specific neurological syndrome seen predominantly among the Ijebu speaking Yorubas in south western Nigeria. In this study, the prevalence of TAN was determined in Ososa, a semiurban community in south western Nigeria described as endemic for TAN in 1969, and its neurological features were compared with Strachan's syndrome, prisoners of war neuropathy, the epidemic neuropathy in Cuba, and konzo.

METHODS

A census of Ososa was followed by door to door screening of all subjects aged 10 years and above with a newly designed screening instrument. Subjects who screened positive had a neurological examination, and the diagnosis of TAN was made if any two or more of bilateral optic atrophy, bilateral neurosensory deafness, sensory gait ataxia, or distal symmetric sensory polyneuropathy were present.

RESULTS

A total of 4583 inhabitants were registered in the census. Of these, 3428 subjects aged 10 years and above were screened. The diagnosis of TAN was made in 206 of 323 subjects who screened positive for TAN. The prevalence of TAN was 6. 0%, 3.9% in males and 7.7% in females. The highest age specific prevalence was 24% in the 60-69 years age group in women.

CONCLUSION

The occurrence of TAN in Ososa continues at a higher prevalence than was reported 30 years ago. Its neurological features and natural history do not resemble those described for Strachan syndrome, epidemic neuropathy in Cuba, or konzo. The increasing consumption of cassava foods linked to its causation makes TAN of public health importance in Nigeria, the most populous African country.

Nutrition and the eye

The topic "nutrition and the eye" cannot adequately be covered in a single review article; indeed, dozens of books and hundreds of articles have been written on the subject. This review concentrates on three areas in which specific nutrients are known or theorized to have a major impact on vision and the visual system: vitamin A deficiency; antioxidants and their proposed role in the prevention of age-related cataract and macular degeneration; and nutritional optic neuropathies, including those of the recent Cuban epidemic. In addition, this article touches on nutritional treatments that have been suggested for several less common eye diseases and, finally, considers several less prevalent conditions in which deficiency of or excess exposure to a particular nutrient has been associated with ocular pathology.