Polyneuropathy Associated with Age of Starting the Transfusion and Serum Ferritin Level in Iranian Patients with Thalassemia Major and Intermedia.

Considering the importance of managing patients with ß-thalassemia and the importance of early detection of disease complications, we examined the rate of sensorimotor neuropathy in patients with ß-thalassemia and the risk factors related to it. This cross-sectional study included 44 blood transfusion-dependent ß-thalassemia patients aged 5 years and older. Nerve conduction studies (NCSs) were performed via standard procedures for both motor and sensory nerves. Neuropathy was observed in 14 patients (31.8%). NCS results for sensorimotor nerves in patients were within normal range. In motor NCS results, increased ulnar nerve amplitude was observed in patients with increasing age, and peroneal nerve delay in patients with an increase in serum ferritin level (p < 0.05). In sensory NCS results, delayed ulnar and sural nerves latencies were found in patients with an increase in serum ferritin level (p < 0.05). We provide data that sensorimotor neuropathy exists in thalassemia patients. It seems that with the increase of serum ferritin level and the age of patients, neuropathy becomes more obvious, while other factors such as gender, body mass index, and the number of transfusions may not be associated with neuropathy.

Is folate deficiency a common cause of distal symmetric polyneuropathy in Zambian clinics?

OBJECTIVES: To evaluate the odds of vitamin B12 and folate deficiencies among Zambian clinic attendees with distal symmetric polyneuropathy (DSP) and age, sex, and HIV matched controls. METHODS: Cases were adults from clinics in urban/peri-urban Zambia. Controls were enrolled among persons not seeking personal medical care, such as a caregiver or person collecting antiretrovirals without a medical complaint. Participants underwent structured interviews, physician examination, and assessments of complete blood count, renal and liver profiles, serum vitamin B12 and folate, erythrocyte folate, plasma total homocysteine and methylmalonic acid. HIV testing and CD4 counts were performed when appropriate. RESULTS: Among 107 consenting matched case-control pairs, 65% were female, 52% HIV positive, with mean age of 47.6 (SD 13.5) years. Among HIV positive participants, mean CD4 count was 484 (SD 221) and 482 (SD 236) for cases and controls, respectively (p = .93). DSP symptoms and severity did not differ by HIV status (p's > 0.05). Height, history of tuberculosis treatment, alcohol use, education, asset index, dietary diversity, and nutritional supplement use did not differ between cases and controls (p's > 0.05). DSP cases had at least 3:1 odds of having low serum folate (p = .0001), severely low erythrocyte folate (p = .014), and elevated total homocysteine (p = .001) levels compared to controls. Markers of vitamin B12 deficiency were not associated with case status (p's > 0.05). CONCLUSION: Markers of folate deficiency are highly associated with DSP among Zambian clinic attendees. Future studies should consider a broader range of comorbid nutritional deficiencies, and strategies for interventions.

Normative concentrations of urine thiocyanate in cassava eating communities in Nigeria.

Exposure to cyanide is a major public health problem where highly cyanogenic cassava foods are consumed. Thiocyanate (SCN), the biomarker of exposure to cyanide is present in several foods, and produced endogenously. Concentrations of urine SCN were measured in endemic and non-endemic areas of ataxic polyneuropathy in Nigeria. Cassava food consumption in the endemic area was twice that of non-endemic areas. Geometrical mean (95% CI) urine SCN was 20 µmol/l (18-24) for no consumption of cassava foods, 56 µmol/l (49-64) for daily consumption, 56 µmol/l (48-65) for twice daily consumption and 85 µmol/l (62-117) for thrice daily consumption. 95th percentile reference limit was 125 µmol/l for no consumption of cassava food, but 360 µmol/l for thrice daily consumption. Urine SCN is a useful biomarker of exposure to cyanide from cassava foods. There is strong ecological association of exposure to cyanide and endemicity of ataxic polyneuropathy.

[Original articles on axonal neuropathy in 2010]. / Les actualités sur les polyneuropathies axonales en 2010.

During 2010, 15 articles were published which focused on chronic sensorimotor axonal neuropathy; some will be discussed in this review. Clinical diagnosis from signs and symptoms seems to be excessively variable, often overestimating the incidence of diabetic sensorimotor polyneuropathy. Long-term use of Metformin is associated with malabsorption of vitamin B12. Metformin exposure may be a iatrogenic cause for exacerbation of peripheral neuropathy in patients with type 2 diabetes. The neuroprotective role of vitamin E against cisplatinperipheral neurotoxicity has been suggested by a phase III study. Metallosis after hip arthroplasty with a cobalt-chromium alloy prosthesis can cause progressive sensory disturbance, hearing loss and hypothyroidism. The effects of electrical stimulation on neuromuscular recovery after nerve crush injury in rats do not support a benefit of the tested protocol using electrical stimulation during the period of motor nerve recovery following injury. The rate of motor vehicle accidents in patients with neuropathy, based on surveys from 260 subjects, demonstrated that 40.6% were involved in traffic accidents. Accident frequency and discomfort with driving are higher in neuropathy patients compared to age-matched national statistics. Peripheral neuropathy in primary (AL) amyloidosis may be the cause of stepwise progressive, multiple upper limb mononeuropathies.

Current concepts in the management of diabetic polyneuropathy.

Approximately one in three people with diabetes is affected by diabetic distal symmetric sensorimotor polyneuropathy (DSPN), which represents a major health problem as it may present with excruciating neuropathic pain and is responsible for substantial morbidity, increased mortality and impaired quality of life. Neuropathic pain causes considerable interference with sleep, daily activities, and enjoyment of life. Treatment is based on four cornerstones: (1) intensive diabetes therapy and multifactorial risk intervention; (2) treatment based on pathogenetic mechanisms; (3) symptomatic treatment; and (4) avoidance of risk factors and complications. Recent experimental studies suggest a multifactorial pathogenesis of diabetic neuropathy. From the clinical point of view, it is important to note that, based on these pathogenetic mechanisms, therapeutic approaches could be derived, some of which are currently being evaluated in clinical trials. Management of chronic painful DSPN remains a challenge for the physician and should consider the following practical rules: the appropriate and effective drug has to be tried and identified in each patient by carefully titrating the dosage based on efficacy and side effects; lack of efficacy should be judged only after 2-4 weeks of treatment using an adequate dosage. Analgesic combination therapy may be useful, and potential drug interactions have to be considered given the frequent polypharmacy in people with diabetes. Not only increased alcohol consumption but also the traditional cardiovascular risk factors such as visceral obesity, hypertension, hyperlipidemia and smoking have a role in the development and progression of diabetic neuropathy and hence need to be prevented or treated.

Distal sensory polyneuropathy in the context of HIV/AIDS.

Peripheral neuropathy, or distal sensory polyneuropathy (DSPN), is the most common neurological problem in HIV disease. DSPN also represents a complex symptom that occurs because of peripheral nerve damage related to advanced HIV disease and in association with the use of antiretroviral therapy-particularly in individuals treated with dideoxynucleosides. Although DSPN is a frequent symptom, the specific pathophysiology is not well understood. The HIV-related neuropathies are commonly categorized as distal sensory polyneuropathies, although antiretroviral toxic neuropathies are described in the literature. Recently, mitochondrial toxicity has been identified as a possible etiology of DSPN. As individuals with HIV/AIDS survive longer, often living for decades with the disease, chronic symptoms like DSPN must be addressed. Pharmacologic approaches, complementary therapies, and self-care behaviors that may improve quality of life and limit symptoms of DSPN are important interventions for clinicians and those living with HIV/AIDS to consider in the management of peripheral neuropathy.

A cluster of polyneuropathy and Wernicke-Korsakoff syndrome in a bariatric unit.

BACKGROUND: Wernicke-Korsakoff syndrome and peripheral neuropathy are very uncommon in bariatric surgical practice. The literature indicates that these complications tend to strike patients receiving unbalanced diets or undergoing rapid weight-loss. METHODS: In a retrospective analysis of the initial experience of a bariatric team in the city of Belem, Pará, in northern Brazil, 5 cases were diagnosed in the first year, 4 of them following gastric bypass and the last one after therapy with an intragastric balloon. RESULTS: All episodes followed periods of severe vomiting, which certainly interfered with intake of food as well as of routine vitamin supplements, resulting in severe polyneuropathy and other neurologic manifestions, mostly damaging motility of lower limbs. Therapy consisted of pharmacologic doses of vitamin B1 along with restoration of adequate diet and multivitamin prescriptions. Physical therapy was employed to prevent atrophy and accelerate normalization of muscle strength. All patients responded to this program after variable intervals without significant sequelae. CONCLUSIONS: Thiamine-related neurologic derangements were a cause for much concern and prolonged morbidity in this series, but responded to vitamin B1 replenishment. A high degree of clinical suspicion in bariatric patients and urgent therapeutic intervention whenever postoperative vomiting persists for several days, especially during the first 2-3 months after operation, are the safest approach to these uncommon episodes. It is speculated whether peculiarities in the regional diet of this area in Brazil could have influenced the high incidence of the neurologic aberrations.