Polineuropatia hipotireóidea em um paciente com síndrome poliglandular autoimune tipo 2: relato de caso / Hypothyroid polyneuropathy in a patient with autoimmune polyglandular syndrome type 2: case report

A incidência de polineuropatia em indivíduos com hipotireoidismo não é precisamente conhecida, mas alguns estudos relatam que cerca de 25% a 42% dos pacientes podem apresentar sinais clínicos neuropáticos. A seguir, relataremos um caso de síndrome poliglandular autoimune tipo 2 (SPA-2), cuja apresentação inicial foi uma polineuropatia hipotireóidea. Homem de 41 anos com queixas de parestesias e fraqueza lentamente progressiva acometendo os quatro membros associadas a sonolência frequente, astenia, intolerância ao frio, vertigens, náuseas e avidez por sal. O exame físico geral evidenciava hiperpigmentação de pele e mucosas, além de hipotensão. O exame neurológico demonstrou apenas hiporreflexia profunda global e simétrica com discretos sinais de hipoestesia superficial em extremidades dos membros. O estudo eletroneuromiográfico (ENMG), juntamente com a avaliação laboratorial, confirmou a suspeita de tireoidite de Hashimoto associada à doença de Addison, caracterizando o quadro de SPA-2. O paciente foi tratado com fludrocortisona 0,05 mg/dia e levotiroxina 100 mcg/dia e apresentou resolução gradual e completa das queixas e das alterações encontradas nos exames físico geral e neurológico. O ENMG, repetido após seis meses, evidenciou resolução completa do quadro neuropático. Este relato mostra um caso raro de SPA-2 apresentando-se como uma polineuropatia hipotireóidea e reforça a relevância da dosagem de hormônios tireoideanos em síndromes polineuropáticas. A reposição de levotiroxina mostrou-se efetiva em reverter o quadro clínico e eletrofisiológico da neuropatia. .

The incidence of polyneuropathy in patients with hypothyroidism is not precisely known, but some studies report that about 25% to 42% of patients may show neuropathic clinical signs. We report a case of autoimmune poliglandular syndrome type 2 (APS-2), whose initial presentation was hypothyroid polyneuropathy. A 41-year-old man complained of slowly progressive paresthesias and weakness affecting all four limbs, and associated with frequent drowsiness, weakness, cold intolerance, dizziness, nausea, and craving for salt. General physical examination showed hyperpigmentation of skin and mucous membranes, and hypotension. Neurological examination showed global, deep, and symmetrical hyporeflexia with slight signs of superficial hypoesthesia in the limbs. Electrodiagnostic studies (ENMG) together with laboratory tests, confirmed the suspicion of Hashimoto’s thyroiditis associated with Addison’s disease featuring the picture of APS-2. The patient was treated with fludrocortisone 0.05 mg/day and levothyroxine 100 mcg/day, and showed gradual and complete resolution of complaints. Changes were found in general physical and neurological examinations. ENMG repeated six months later showed complete resolution of neuropathy. This report shows a rare case of APS-2 presented as polyneuropathy hypothyroidism, and reinforces the importance of dosing thyroid hormone in polyneuropathy syndromes. Levothyroxine replacement was shown to be effective in reversing clinical and electrophysiologic neuropathy.

Evaluación del efecto del tratamiento con ácido lipoico administrado a la rata Wistar intoxicada con el fruto de Karwinskia humboldtiana / Evaluation of the effect of treatment with lipoic acid administered to the Wistar rat intoxicated with the fruit of Karwinskia humboldtiana

La ingesta accidental de fruto de Karwinskia humboldtiana ocasiona una parálisis flácida, simétrica, progresiva y ascendente, similar al síndrome de Guillain-Barré. Evoluciona en el transcurso de 3 a 12 meses hasta su recuperación total, pero los casos graves terminan en la muerte por insuficiencia respiratoria. No existe un tratamiento específico. La lesión histopatológica descrita en nervio periférico de pacientes, y animales de experimentación corresponde a una desmielinización segmentaria acompañada de degeneración Walleriana. Una de las toxinas extraídas a partir de la semilla, la T-514, ocasiona un incremento de radicales libres in vitro. Los radicales libres se han relacionado con la desmielinización que se presenta en otros tipos de neuropatías como en la diabética. Ya que la lesión ultraestructural que se presenta en los modelos animales de diabetes es similar a la que se observa en la intoxicación experimental con fruto de K. humboldtiana, se decidió administrar un potente agente antioxidante, el ácido a-lipoico en un modelo de intoxicación crónica por fruto de K. humboldtiana. Sin embargo, no se observó mejoría sobre las manifestaciones clínicas evaluadas en los animales o sobre las lesiones histopatológicas presentes en el nervio periférico. Estos resultados sugieren que los radicales libres no son el mecanismo principal de lesión sobre el nervio periférico en la polineuropatía causada por K. humboldtiana.

The accidental ingestion of Karwinskia humboldtiana causes a flaccid, symmetrical, progressive and ascending paralysis, similar to Guillain-Barre syndrome. It evolves over the course of 3 to 12 months until full recovery, but severe cases end in death due to respiratory failure. There is no specific treatment. The histopathological lesions described in peripheral nerve of patients and in experimental animals, corresponds to segmental demyelination accompanied by Wallerian degeneration. One of the toxins extracted from the seed, T-514, causes an increase of free radicals in vitro. Free radicals have been associated to demyelination that occurs in other types of neuropathy such as diabetic neuropathy. Since the ultrastructural damage that occurs in animal models of diabetes is similar to that observed in experimental poisoning with the fruit of K. humboldtiana, we decided to administer a powerful antioxidant, a-lipoic acid, in a model of chronic poisoning due of K. humboldtiana. However, no improvement was observed on the clinical manifestations evaluated in animals or in the histopathological lesions in the peripheral nerve. These results suggest that free radicals are not the primary mechanism of injury on the peripheral nerve caused by K. humboldtiana.

Use of pyridoxine and pyridostigmine in children with vincristine-induced neuropathy.

Four children with vincristine (VCR)-induced neuropathy are being reported. All cases were followed with the diagnosis of acute lymphoblastic leukemia. Two were boys aged between 2 and 13 year. Electromyographic examination consisted of sensoriomotor polyneuropathy with axonal involvement in three patients. In another patient, it consisted of motor axonal polyneuropathy. In all patients, pyridoxine and pyridostigmine were successfully used in the treatment of VCR-induced neuropathy. They recovered completely with this drug combination. Recovering period of symptoms was between 1-2 week.

Prednisolone as a new approach for treatment of HTLV-1 associated polyneuropathy

We have previously shown the implication of HTLV-1 in polyneuropathy in a HTLV-1 endemic area in Mashhad. Treatment with corticosteroids [prednisolone and methylprednisolone] have been recommended for HTLV-1 associated diseases. In the current study we attempted to evaluate the efficiency of prednisolone in HTLV-1 associated polyneuropathy. All recognized cases of HTLV-1 polyneuropathy admitted to Imam Reza Hospital [between 1999-2004] were selected for the study. The other common causes of polyneuropathy were excluded using biochemical, hematological, and neurologic examination. Anti-HTLV1 IgG assays were carried out and positive anti-HTLV-1 results were then confirmed by Western Blot Analyzing. All of the HTLV-1 associated polyneuropathy patients were given prednisolone, 1mg/ kg and tapering 5mg/ per week, for three month. Muscle force and paresthesia of all cases were returned to normal pattern. This therapeutic regimen led to reduction of disease severity. Muscle force increased to V/V and paresthesia of all cases were severely decreased. The results of present study suggest that immunosuppressive treatment is very effective for HTLV-1 associated polyneuropathy patients

Acute axonal polyneuropathy with predominant proximal involvement: an uncommon neurological complication of bariatric surgery / Polineuropatia axonal aguda com acometimento proximal predominante: manifestação neurológica incomum de cirurgia bariátrica

Bariatric surgery is frequently indicated in the treatment of morbid obesity. Previously unreported complications have been associated to this surgery; among them, neurological complications have gained attention. We report the case of a 25-year-old man submitted to gastric surgery for treatment of morbid obesity who developed, two months after surgery, acute proximal weakness in lower limbs. The electroneuromyography revealed axonal peripheral polyneuropathy with predominant proximal involvement. After treatment with immunoglobulin and vitamin supplementation, rapid clinical and neurophysiologic recovery was observed. We describe the clinical and electroneuromyographic features of this case, stressing the difficulty of initial diagnosis, particularly in the differential diagnosis with Guillain-Barré syndrome. We discuss the importance of nutritional follow-up and the eventual indication of routine vitamin supplementation in these patients.

A cirurgia bariátrica é freqüentemente indicada no tratamento da obesidade mórbida. Complicações previamente não relatadas têm sido associadas a essa cirurgia; dentre estas, as complicações neurológicas têm recebido destaque. Relatamos o caso de um homem de 25 anos de idade submetido a cirurgia gástrica para tratamento de obesidade mórbida que desenvolveu, dois meses após a cirurgia, fraqueza de predomínio proximal nos membros inferiores, de instalação aguda. A eletroneuromiografia demonstrou polineuropatia periférica axonal nos membros inferiores, de predomínio proximal. Após tratamento com imunoglobulina e suplementação vitamínica, apresentou rápida melhora clínica e neurofisiológica. Descrevemos as características clínicas e eletroneuromiográficas desse caso, destacando a dificuldade diagnóstica inicial, particularmente com relação ao diagnóstico diferencial com síndrome de Guillain-Barré. Discutimos a importância de acompanhamento nutricional e a eventual indicação de suplementação vitamínica de rotina nesses pacientes.