Clinical, electrophysiological profile and prognosis in paraneoplastic syndrome with SRY-like high-mobility group superfamily of developmental transcription factors 1 antibody / 中华神经科杂志

Objective To summarize the clinical,electrophysiological profile and prognosis in paraneoplastic syndrome with SRY-like high-mobility group superfamily of developmental transcription factors (SOX) 1 antibody.Methods The clinical profile,laboratory examination,electrophysiology,tumor,treatment and prognosis of three patients of paraneoplastic syndrome with SOX1 antibody in Tangdu Hospital,Air Force Military Medical University from 2016 to 2018 were retrospectively analyzed.Results Proximal lower limbs weakness was the first symptom in all the three patients,weakness normally spreading proximally to distally,involving feet and hands,finally reaching the oculobulbar region,and dry mouth was the most common autonomic dysfunction.Compound muscle action potential (CMAP) amplitude was low in all the patients,and the CMAP amplitude became even lower at low stimulating frequencies.An increase in CMAP amplitude with high-frequency stimulation was found in two patients during the follow-up.Lambert-Eaton myasthenic syndrome (LEMS) and motor axonal peripheral neuropathy were considered.Acetylcholine receptors antibody was positive in one case and voltage-gated calcium channel antibody was positive in another case.Two cases were found complicated with small cell lung carcinoma,one case with small cell carcinoma of the esophagus.After treatment of intravenous immunoglobulin,chemotherapy and pyridostigmine,the prognosis of the patients was different.Conclusions SOX1 antibody as an antibody in paraneoplastic syndrome,is most common in small cell lung cancer with LEMS,sometimes with axonal peripheral neuropathy.LEMS needs to be considered when patients manifest proximal limb weakness and dry mouth,and screening for tumors is needed.

Lambert-Eaton myasthenic syndrome: the 60th anniversary of Eaton and Lambert's pioneering article / Síndrome miastênica de Lambert-Eaton: o 60° aniversário do artigo pioneiro de Eaton e Lambert

ABSTRACT This historical review describes the contribution of Drs. Lee M. Eaton and Edward H. Lambert to the diagnosis of myasthenic syndrome on the 60th anniversary of their pioneering article (JAMA 1957) on the disease. There are important landmarks in their article on a disorder of the neuromuscular junction associated with thoracic neoplasm and the electrophysiological criteria for Lambert-Eaton myasthenic syndrome (LEMS). After 60 years, the main electrophysiological criteria described in Eaton and Lambert's pioneering article are still currently useful in the diagnosis of LEMS.

RESUMO Essa revisão histórica enfatiza a contribuição do Dr Lee M Eaton e do Dr Edward H. Lambert para o diagnóstico da síndrome miastênica no 60o aniversário do seu artigo pioneiro (JAMA 1957) para essa doença. Existem importantes marcos no artigo de Eaton e Lambert, como uma desordem da junção neuromuscular associada à neoplasia torácica e critério diagnóstico para síndrome miastênica de Lambert-Eaton (LEMS). Após 60 anos, os principais critérios diagnósticos descritos para LEMS no artigo pioneiro de Eaton e Lambert continuam úteis no diagnóstico da LEMS.

A Case of Lambert-Eaton Myasthenic Syndrome with Small-Cell Lung Cancer and Transient Increase in Anti-Acetylcholine-Receptor-Binding Antibody Titer

BACKGROUND: Lambert-Eaton myasthenic syndrome (LEMS) is a presynaptic neuromuscular junction disorder that is most frequently associated with small-cell lung cancer (SCLC). The titers of antibodies against voltage-gated calcium channels are frequently increased in LEMS, but only rarely is titer of anti-acetylcholine-receptor-binding antibodies (AChR-abs) increased. CASE REPORT: A 57-year-old male was admitted to our hospital due to dry mouth and eyes and progressive proximal limb weakness of 2 months duration. The results of a repetitive nerve stimulation test disclosed all criteria for the electrophysiological LEMS pattern, and the patient's AChR-abs titer was 0.587 nmol/L. At a follow-up performed 5 years after successful treatment of SCLC and LEMS, his AChR-abs titer had decreased to 0.001 nmol/L. CONCLUSIONS: We suggest that this was a case of transient pseudopositivity of AChR-abs in SCLC with LEMS.

A Patient with Coexisting Myasthenia Gravis and Lambert-Eaton Myasthenic Syndrome

BACKGROUND: The coexistence of myasthenia gravis (MG) and Lambert-Eaton myasthenic syndrome (LEMS) is very rare and remains controversial. CASE REPORT: A 48-year-old woman initially presented with noticeable right ptosis and intermittent diplopia. She then developed fluctuating proximal limb weakness and difficulty in swallowing. The serum titer of anti-acetylcholine-receptor antibody was elevated and the edrophonium (Tensilon) test was positive. However, repetitive nerve stimulation revealed abnormalities typical of LEMS. The patient exhibited a good response to treatment with anticholinesterase inhibitors and steroids, and long-term evaluation disclosed that she presented with the clinical, electrophysiological, and immunological characteristics of both diseases. CONCLUSIONS: The reported clinical and electrophysiological features suggest that this patient was a very rare case of combined MG and LEMS.

Non-paraneoplastic Lambert-Eaton myasthenic syndrome: a brief review of 10 cases / Síndrome miastênica de Lambert-Eaton não paraneoplásica: uma breve revisão de dez casos

Lambert-Eaton myasthenic syndrome (LEMS) is an immune-mediated disorder of the presynaptic neuromuscular transmission, which more frequently occurs as the remote effect of a neoplasm, in the paraneoplastic form (P-LEMS), or in a non-paraneoplastic form (NP-LEMS); but few studies describe the clinical features of NP-LEMS. We analyzed the clinical manifestations, laboratory findings, electrophysiological studies, and treatment responses in ten Brazilian patients suffering from NP-LEMS. The mean age was 41.5 years. More often neurological findings were hyporeflexia or areflexia with a post-exercise improvement. Treatment response occurred with pyridostigmine, guanidine, prednisone, azathioprine, and cyclosporine; but not response was observed after intravenous immunoglobulin and plasma exchange. Age at onset, clinical manifestations, and electrophysiological abnormalities can help more in the diagnosis than serum antibodies; the symptomatic treatment with pyridostigmine was effective; and the immunosuppressive treatment with prednisone, azathioprine, or cyclosporine was more beneficial than plasma exchange or intravenous immunoglobulin treatment.

A síndrome miastênica de Lambert-Eaton (LEMS) é uma desordem imunomediada da transmissão neuromuscular pré-sinaptica, que mais frequentemente ocorre como efeito à distância de uma neoplasia, na forma paraneoplásica (P-LEMS), ou na forma não paraneoplásica (NP-LEMS); porém poucos estudos têm descrito as características da NP-LEMS. Nós analisamos as manifestações clínicas, laboratoriais, eletrofisiológicas, e resposta ao tratamento em dez pacientes brasileiros com NP-LEMS. A idade média foi de 41,5 anos. A manifestação neurológica mais freqüente foi hiporeflexia ou arreflexia com melhora após o exercício. A resposta ao tratamento ocorreu com piridostigmina, guanidina, prednisona, azatioprina, e ciclosporina; mas não com imunoglobulina intravenosa e plasmaférese. A idade de início, manifestações clínicas e eletrofisiológicas ajudaram mais no diagnóstico do que os anticorpos séricos; o tratamento sintomático com piridostigmina foi efetivo; e o tratamento imunossupressor com prednisona, azatioprina, ou ciclosporina beneficiou mais do que a plasmaférese ou a imunoglobulina intravenosa.

Lambert-Eaton myasthenic syndrome as a cause of persistent neuromuscular weakness after a mediastinoscopic biopsy: A case report / 대한마취과학회지

There are many causes of prolonged postoperative muscle weakness, including drugs, residual anesthetics, cerebrovascular events, electrolyte imbalance, hypothermia, and neuromuscular disease. Neuromuscular diseases are relatively rare, with the most common being myasthenia gravis and Lambert-Eaton myasthenic syndrome (LEMS). We report an unusual case in which a patient who was given a muscle relaxant during mediastinoscopy developed postoperative muscle weakness that was ultimately diagnosed as secondary to LEMS.

Lambert-Eaton Myasthenic Syndrome (LEMS) Presented With Ocular Symptoms

Lambert-Eaton myasthenic syndrome (LEMS) is characterized clinically by fluctuating muscular weakness; presentation with ocular symptoms is unusual. A 60-year-old man had developed diplopia and ptosis 2 years previously. The findings of a neurologic examination were normal except for bilateral ptosis and ophthalmoplegia. The amplitude of compound muscle action potentials recorded on the abductor digiti minimi increased (by more than 500%) during 50-Hz stimulation. This case demonstrates that LEMS should be included in the differential diagnosis of myasthenic symptom confined to the ocular muscles.

Clinical and electrophysiological characteristics of Lambert-Eaton myasthenic syndrome: a retrospective study in forty-five patients / 中华神经科杂志

Objective To analyze the symptoms and signs in forty-five Lambert-Eaton myasthenia syndrome (LEMS) patients retrospectively. Characteristics of electrophysiological examinations were investgated. Methods Forty-five LEMS patients were reviewed and information gathered regarding clinical complains neurological symptoms, and other concomitant diseases. The records showed that repetitive nerve stimulation (RNS) and nerve conduction velocity (NCV) were performed in all patients. Needle electromyography (EMG) and skin sympathetic response (SSR) were performed in some patients. Results (1) The mean age of neurological clinical onset age was (51.2 ±6. 8) years old. The two most common symptoms were slight weakness of lower extremities ( n = 35 ) and upper extremities (n= 5). Dysarthria was found in 3 patients and neck weakness in 2 patients. Tendon reflex decreased and disappeared in 38 patients. Autonomic nervous system manifestations were presented in 30 patients. (2) RNS increasing was observed in all patients from 156% to 636%. Low frequency RNS abnormalities were found in 29 patients.Sensory nerve conduction velocity abnormalities or sensory nerve conduction velocity combined motor nerve conduction velocity abnormalities were found in 19 patients ( 42% ). Of the 30 patients who underwent a needle EMG examination, 20 had myogenic or neurological damage. Thirteen abnormal findings were observed in 25 patients who underwent SSR examination. Conclusion The most common manifestations were weakness in lower extremities and autonomic nervous system dysfunction. Many abnormal electrophysiological results were found in LEMS patients, including NCV and EMG abnormalities. These findings indicated that clinical manifestations exceed the neuromuscular junction and perhaps included the peripheral nerve and muscle.

Surgical correction of strabismus in Lambert-Eaton myasthenic syndrome: case reports / Correção cirúrgica do estrabismo na síndrome de Lambert-Eaton: relato de dois casos

Lambert-Eaton myasthenic syndrome is a rare and acquired autoimmune disorder. We describe two female patients with medial rectus paresis as the only ocular manifestation. After a unilateral medial rectus recession and lateral rectus resection procedure, both patients recovered normal adduction. To our knowledge, this is the first report of surgery for extraocular muscle paresis in Lambert-Eaton myasthenic syndrome.

A síndrome de Lambert-Eaton é um distúrbio autoimune raro e adquirido. Apresentamos duas pacientes com paresia do reto medial como única manifestação ocular. Após retrocesso do reto lateral e ressecção do reto medial, unilateral, ambas as pacientes apresentaram normalização da adução. Até onde sabemos, este é o primeiro relato de cirurgia para paresia do reto medial na síndrome de Lambert-Eaton.

Adenocarcinoma pulmonar, dermatomiosite e síndrome miastênica de Lambert-Eaton: uma rara associação / Lung adenocarcinoma, dermatomyositis, and Lambert-Eaton myasthenic syndrome: a rare combination

A incidência das neoplasias pulmonares vem aumentando no Brasil e no mundo, provavelmente como resultado do aumento do tabagismo. Com o maior número de casos, surgem as apresentações atípicas. Relatamos o caso de um paciente do sexo masculino, 66 anos, tabagista e hipertenso, que apresentava quadro de fraqueza muscular proximal progressiva e, em dois meses, evoluiu com disfagia para alimentos sólidos, disfonia e lesões cutâneas em forma de "V" no tórax. O radiograma de tórax mostrou um nódulo pulmonar espiculado no lobo superior direito. A análise bioquímica revelou aumento da creatinoquinase. Após exames complementares e biópsias, o paciente foi submetido à lobectomia superior direita. A histopatologia evidenciou um adenocarcinoma moderadamente diferenciado. A análise global do caso e a revisão de literatura permitem sugerir que o quadro clínico do paciente era resultante da sobreposição de duas síndromes paraneoplásicas, a saber, a dermatomiosite e a síndrome miastênica de Lambert-Eaton, secundárias a um adenocarcinoma pulmonar.

The incidence of lung neoplasms is increasing in Brazil and in the world, probably as a result of the increase in smoking. Due to the greater number of cases, atypical presentations appear. We report the case of a 66-year-old hypertensive male smoker who presented progressive proximal muscular weakness and, in two months, evolved to dysphagia, dysphonia, and V-shaped skin lesions on the chest. A chest X-ray showed a spiculated pulmonary nodule in the right upper lobe. The biochemical analysis revealed elevated creatine kinase levels. After complementary tests and biopsies, the patient underwent right upper lobectomy. Histopathology showed a moderately differentiated adenocarcinoma. The overall analysis of the case and a review of the literature allow us to suggest that the clinical profile of the patient was a result of an overlap of two paraneoplastic syndromes (dermatomyositis and Lambert-Eaton myasthenic syndrome) secondary to lung adenocarcinoma.

Electrophysiological Changes in Lambert-Eaton Myasthenic Syndrome With Intravenous Immunoglobulin Therapy

No abstract available.

A Case of Lambert-Eaton Myasthenic Syndrome with Positive VGCC Antibodies Diagnosed in Small Cell Lung Cancer / 결핵및호흡기질환

Lambert-Eaton myasthenic syndrome (LEMS), a rare autoimmune neurological syndrome, is caused by defects in the secretion of acetylcholine from the presynaptic membrane, and is associated with the destruction of voltage gated calcium channels (VGCC) in the neuromuscular junction. LEMS can be confirmed by repetitive nerve stimulation and by the clinical symptoms, which are characterized by proximal muscle weakness in the lower extremities, decreased deep tendon reflexes and autonomic dysfunctions. In about 60% of patients with this disorder, underlying cancer-small cell lung cancer may be detected. Clinical symptoms may precede the diagnosis of malignancy, with the early diagnosis and treatment of the underlying malignancy being possible through the diagnosis of LEMS. A case of LEMS, with positive VGCC antibodies, in a 48-year-old man, which improved after chemotherapy of the underlying small cell lung cancer, is reported.

A Case of Lambert-Eaton Myasthenic Syndrome Associated with Atypical Bronchopulmonary Carcinoid Tumor

The Lambert-Eaton myasthenic syndrome (LEMS) is typically recognized as a paraneoplastic syndrome associated with a small cell lung carcinoma (SCLC), whereas LEMS with other neuroendocrine lung tumors, including carcinoids or large cell lung carcinoma, are highly unusual. Here, we report a rare case of LEMS with atypical bronchopulmonary carcinoid tumor: A 65-yr-old man presented with progressive leg weakness and a diagnosis of LEMS was made by serial repetitive nerve stimulation test. Chest CT revealed a lung nodule with enlargement of paratracheal lymph nodes, and surgically resected lesion showed pathological features of atypical carcinoid tumor. We concluded that LEMS could be associated with rare pulmonary neuroendocrine tumor other than SCLC, which necessitates pathologic confirmation followed by aggressive treatment for optimal management in these rare cases.

Clinical analysis of 12 Korean Lambert-Eaton myasthenic syndrome (LEMS) patients

The Lambert-Eaton myasthenic syndrome (LEMS) heralds the occurrence of malignancy, especially small-cell lung cancer (SCLC), but it can also occur in the absence of cancer. Twelve patients were diagnosed as LEMS by clinical features and the classical electrophysiological triad, which includes a low amplitude of compound muscle action potentials (CMAP), decremental responses on low-rate stimulation, and incremental responses on high-rate stimulation on the repetitive nerve stimulation (RNS) test. There were 6 male and 6 female patients, ranging in age from 49 to 66 years. Malignancy(all were SCLC) was found in 7 patients. Males predominantly expressed the paraneoplastic form; whereas the primary autoimmune form was found only in women, who showed a good response to corticosteroid treatment. The neurological features were similar in both groups: proximal lower limb weakness, depressed muscle stretch reflexes, and dryness of mouth in nearly all patients. Bulbar dysfunction and limb paresthesia were a little more frequent in the paraneoplastic form. In RNS tests, the characteristic electrophysiological abnormalities were found in all patients and were more profound in the paraneoplastic form. We concluded that LEMS is commonly associated with malignancy, especially SCLC, but it should also be stressed that there are many female LEMS patients who do not harbor any malignancy at all, and that other treatment strategies such as immunotherapy should be considered for these patients.

A Case of Lambert-Eaton Myasthenic Syndrome Improved after Surgical Resection for Diagnosis of Small Cell carcinoma of the Lung / 결핵

Lambert Eaton myasthenic syndrome(LEMS) is a paraneoplastic syndrome caused by defects in the secretion of acetylcholine from the presynaptic membrane of nerve terminals and is strongly associated with small cell lung carcinoma. The pathogenesis of LEMS is the destruction of voltage gated calcium channels by an autoimmune process resulting in clinical manifestations consisting of lower extremity weakness, decreased deep tendon reflexes and autonomic dysfunctions. The diagnosis can be confirmed by the characteristic clinical features and repetitive nerve stimulation. The neurological symptoms and signs of LEMS may manifest themselves months before the clinical manifestation of the underlying malignancy. Therefore early diagnosis and treatment of the primary malignancy may become possible through the diagnosis of this rare paraneoplastic syndrome. We report a case of a patient diagnosed with LEMS who upon further evaluation for an underlying malignancy was found to have a 0.2cm sized nodular and infiltrative mass lesion at the bifurcation of the left apicoposterior segmental and anterior segmental bronchi by bronchoscopy. Although repeated bronchoscopic biopsies of the lesion was not able to disclose malignancy, under strong clinical suspicion left upper lobectomy was performed and subsequently the diagnosis of small cell carcinoma of the lung was confirmed. Muscle weakness began to improve starting from a week after the surgery, then reached a plateau 2 weeks later. Muscle weakness improved further after the trial of anticancer chemotherapy.