Incidence and mortality rates of myasthenia gravis and myasthenic crisis in US hospitals.

OBJECTIVE: To determine the incidence and mortality rates and predictors of death in myasthenia gravis (MG) and MG crisis in a large US cohort. METHODS: Our cohort was identified from the Nationwide Inpatient Sample database for the years 2000 through 2005 using ICD-9-CM codes. MG crisis was identified by the principal diagnosis code or by the presence of respiratory failure. The incidence of MG was stratified by age, ethnicity, and gender. Multivariate logistic regression analysis was used to identify predictors of mortality in MG. For trend analyses of immune intervention, we used the Cochrane-Armitage test. RESULTS: After data cleansing, 5,502 patients with MG were included. In women, the incidence of admission was two to three times higher during the first 5 decades. In men, the incidence of admission was higher during the sixth, seventh, and eighth decades. The annual incidence rate of MG was higher in black women (0.01 per 1,000 persons/year) compared to white women and white and black men (0.009, 0.008, and 0.007 per 1,000 persons/year). The overall in-hospital mortality rate was 2.2%, being higher in MG crisis (4.47%). Older age and respiratory failure were the predictors of death, with adjusted odds ratios of 9.28 (95% confidence interval [CI], 3.31, 26.0) and 3.58 (95% CI, 2.01, 6.38). The trend of i.v. immunoglobulin utilization has increased compared to plasma exchange and thymectomy (p < 0.0001). CONCLUSION: Myasthenia gravis (MG) is still a disease of young women and old men, as reflected by the hospital admission rates. In-hospital mortality of MG is low. Hospital utilization of i.v. immunoglobulin has significantly increased compared to plasma exchange and thymectomy.

Chronic ataxic neuropathy mimicking dorsal midbrain syndrome.

We describe the clinical course, with special attention to the disturbance of eye movements, of a 29-year-old man with chronic ataxic neuropathy with ophthalmoplegia, IgM paraprotein, cold agglutinins and anti-GD1b disialosyl antibodies (CANOMAD). Using the magnetic search coil technique, we documented convergence during upward saccades and other features suggestive of dorsal midbrain syndrome. Thus, in common with Miller Fisher syndrome, CANOMAD may present with clinical findings implicating involvement of the central nervous system, which contains ganglioside antigens to anti-GD1b antibodies.

Sensory Mononeuropathy Multiplex in Chronic Graft versus Host Disease.

Graft versus host disease (GVHD) is a frequent complication of bone marrow transplantation (BMT). Peripheral neuropathies in association with chronic GVHD are uncommon. We report a patient with BHT for chronic myeloid leukemia, and chronic GVHD with severe sclerodermatitis resulting in bilateral medial antebrachial and saphenous sensory mononeuropathies.

Multifocal motor neuropathy presenting with respiratory failure.

Multifocal motor neuropathy is a disorder characterized by slowly progressive asymmetrical limb weakness and multiple motor conduction blocks. We report a 56-year-old woman with this disorder who presented unusually with respiratory failure and who initially had absent responses to phrenic nerve stimulation bilaterally. The mechanism of the patient's respiratory failure may have been chronic conduction blocks in the phrenic nerves leading to diaphragmatic weakness.

Brachial plexopathy in diabetic ketoacidosis.

We report the clinical and electrodiagnostic findings of a 39-year-old patient who presented with severe, bilateral and asymmetrical, axon-loss brachial plexopathies occurring in the midst of diabetic ketoacidosis. This patient's unusual presentation is not consistent with the rare diabetic polyradiculopathy of the upper extremities usually occurring in association with diabetic amyotrophy.

Lambert-eaton myasthenic syndrome: a harbinger to transitional cell carcinoma of the urinary bladder.

A 72-year-old man developed Lambert-Eaton myasthenic syndrome (LEMS) with typical electrodiagnostic findings and elevated serum antibodies to the P/Q-type voltage-gated calcium channels. Two years after diagnosis, he had transitional cell carcinoma of the bladder (TCCB), There was no evidence of small cell lung cancer (SCLC) 5,5 years after the onset of the symptoms. In this article I review the association of LEMS with cancer other than SCLC, and discuss the paraneoplastic characteristics of TCCB.

Inflammatory myopathy in hemiatrophy resulting from linear scleroderma.

Hemiatrophy caused by linear scleroderma is a race clinical entity of unknown etiology. We present a patient with an inflammatory myopathy in hemiatrophy resulting from linear scleroderma.

Neuromuscular transmission defect caused by carbamazepine.

The clinical effect of carbamazepine (CBZ) on neuromuscular transmission is described in two children who presented in coma with diffuse hypotonia and areflexia following CBZ overdose. Repetitive nerve stimulation (RNS) showed a decremental response only at high-frequency stimulation. With supportive care, the patients made an uneventful recovery. Follow-up RNS was normal. This is the first report of a clinically evident neuromuscular transmission defect produced by CBZ. We postulate that CBZ's known effect on decreasing sodium channel depolarization produced a defect in neuromuscular transmission. The report emphasizes the contribution of RNS in the evaluation of coma of uncertain etiology, particularly in cases of possible intoxication, and the potential for CBZ to compromise neuromuscular transmission in normal individuals or in patients with a decreased neuromuscular transmission safety factor.

Peroneal neuropathy.

The clinical and electrodiagnostic presentation of peroneal neuropathies are detailed in this article. There is a special emphasis on nerve conduction study findings and their relationship to prognosis and management. The differential diagnosis of foot drop, including when caused by the anterior compartmental syndrome of the leg, is also discussed.

Total innervation of the extensor digitorum brevis by the accessory deep peroneal nerve.

We describe a patient with complete (100%) innervation of the extensor digitorum brevis muscle by the accessory deep peroneal nerve, which resulted in an erroneous diagnosis of peroneal mononeuropathy.

Guillain-Barré syndrome after Cyclospora infection.

We present a patient who developed Guillain-Barré syndrome (GBS) after a Cyclospora-induced diarrheal illness. We raise the possibility that Cyclospora is an infectious trigger for GBS in this patient. An active search for this agent in patients with GBS preceded by diarrheal illness is recommended.

Chronic relapsing axonal neuropathy responsive to intravenous immunoglobulin.

Chronic relapsing axonal neuropathy is uncommon. I describe a 68-year-old patient who responded rapidly and repeatedly to intravenous immunoglobulin treatment.

Evaluation of a program for long-term treatment of Duchenne muscular dystrophy. Experience at the University Hospitals of Cleveland.

One hundred and forty-four boys who had Duchenne muscular dystrophy were managed at a single center between 1953 and 1994 and were followed for a mean of 8.9 years. The long duration of follow-up provided an opportunity to examine the effects of physical therapy and orthopaedic treatment on contractures of the lower extremities and on the duration of the ability to walk. Contractures of the lower extremities were controlled best when patients were managed with a combination of daily passive stretching exercises, prescribed periods of standing and walking, tenotomy of the Achilles tendon, posterior tibial-tendon transfer, and application of knee-ankle-foot orthoses. Approximately two years after bracing, the severity of the contracture of the heel cords was similar in the patients who had had an operation and those who had not. By the fourth year after bracing, however, the patients who had had an operation had less severe contractures than those who had had bracing alone. Five to seven years after the operation and bracing, control of contractures was still good, especially for the patients who had had posterior tibial-tendon transfer. Contracture of the knee was well controlled five to seven years after bracing in all patients who had had bracing, with or without an operation. The program enabled the patients who had been managed with bracing to walk until a mean age of 13.6 years. After loss of the ability to walk with bracing, the ability to stand continued for an additional two years with use of orthoses. The findings of the present study demonstrate the value of traditional methods of operative treatment and bracing for controlling contractures of the lower extremities in patients who have Duchenne muscular dystrophy and for prolonging their ability to walk.

Classic neurogenic thoracic outlet syndrome in a competitive swimmer: a true scalenus anticus syndrome.

Neurogenic thoracic outlet syndrome (TOS) is caused by compression of the lower brachial plexus usually by a cervical rib or a fibrous band. We describe a 16-year-old girl with weakness and wasting of her right hand, which progressed over the ensuing years. She had been a competitive long distance freestyle and butterfly swimmer since age 8 years. A neurological exam at age 20, revealed severe atrophy and weakness of all intrinsic right hand muscles, more so of the thenar muscles, and hypesthesia along the ulnar aspect of the hand and forearm. EMG, which showed a severe chronic axon loss lower trunk brachial plexopathy with minimal fibrillations, was typical for classic neurogenic TOS. Chest and cervical spine X-rays and MRI of the cervical spine were normal. A supraclavicular exploration confirmed the absence of a cervical rib or band. The lower trunk was thickened under the scalenus anticus which was sectioned. Neurolysis was also done. She was advised to abandon swimming. A clinical and EMG follow-up 2.5 years later showed no significant changes. This is the first case of true neurogenic TOS caused by scalenus anticus compression occurring in a competitive swimmer.