Plasma exchange versus intravenous immunoglobulin treatment in myasthenic crisis.

We performed a retrospective multicenter chart review to compare the efficacy and tolerance of plasma exchange (PE) and intravenous immunoglobulin (i.v.Ig) in treatment of 54 episodes of myasthenic crisis. After adjustment for other variables, PE (compared with i.v.Ig) was associated with a superior ventilatory status at 2 weeks (partial F = 6.2, p = 0.02) and 1 month functional outcome (partial F = 4.5, p = 0.04). However, the complication rate was higher with PE compared with i.v.Ig (13 versus 5 episodes, p = 0.07).

Guillain-Barré syndrome in immunocompromised patients: a report of three patients and review of the literature.

Both humoral and cell-mediated autoimmune mechanisms have been implicated in the pathogenesis of Guillain-Barré syndrome (GBS). Therefore, its occurrence in severely immunocompromised patients is not expected. We identified 3 severely immunocompromised patients who developed GBS. Two of the 3 patients had acquired immunodeficiency syndrome with CD4 counts of 5 and 4 cells/mm3, respectively. One post-cardiac transplant patient was taking azathioprine and cyclosporine at the time of onset of GBS. In all 3 patients, immunocompromise was induced by infectious or chemotherapeutic agents which preferentially suppress T-lymphocyte responses. All 3 had severe lymphocytopenia and incomplete recovery. We conclude that GBS can occur in patients with severe t-cell suppression. Although no conclusion regarding prognosis can be drawn from our small group of patients, their incomplete recovery is consistent with the idea that T-cells are important for recovery.

Autoimmune diabetic neuropathy.

Recent work has shown that inflammatory vasculopathy is commonly seen in biopsies of diabetic patients with neuropathy. Most of these patients have had syndromes consistent with proximal diabetic neuropathy or amyotrophy. This suggests that inflammatory vasculopathy is important in the pathogenesis of these disorders. Immunosuppressive therapy may benefit many of these patients.

Motor neuron disease with parkinsonism.

OBJECTIVE: To report clinical characteristics of patients with combined features of parkinsonism and motor neuron disease (MND). DESIGN: Medical chart review. SETTING: University medical center. PATIENTS: Thirteen patients, identified by computer-assisted search, who had diagnoses of both parkinsonism and MND. RESULTS: Median age was 68 years. There were 7 men and 6 women. All had clinical and electrodiagnostic evidence of both upper and lower motor neuron degeneration. One or more clinical manifestations of parkinsonism were observed in all patients either before the diagnosis of MND (n = 2), at the time of initial evaluation (n = 10), or after the diagnosis of MND (n = 1). The median time from symptom onset to presentation was 18 months. Improvement was seen in 5 of the 11 patients treated with levodopa. Dementia and autonomic dysfunction were absent in all patients. Postmortem neuropathological evaluation, available in 1 patient, demonstrated degeneration of the substantia nigra with Lewy bodies, mild pallor of the medullary pyramids, and neurogenic atrophy of the skeletal muscle. CONCLUSION: The onset of MND and parkinsonism within a relatively short period in most of our patients favors a common pathogenic mechanism over coincidental occurrence of 2 unrelated diseases. In patients with MND, it is important to recognize signs of parkinsonism that levodopa might alleviate.

Diabetic muscle infarction.

PURPOSE: To describe the clinical, histologic, and radiologic findings in patients with diabetic muscular infarction (DMI). MATERIALS AND METHODS: Descriptive case series of 3 patients with DMI and 22 previously reported cases (MEDLINE data base search) in the English literature are presented. RESULTS: Diabetic muscular infarction is usually seen in patients with long-standing insulin-dependent diabetes and multiple end-organ microvascular complications. Two-thirds of patients with DMI are women, with a mean age at presentation of 39 +/- 12 years. The typical clinical presentation includes abrupt onset of thigh pain and tenderness. There is a palpable, painful mass, with swelling and induration of the surrounding tissue without systemic symptoms or signs. The painful lesion persists for weeks, occasionally with exacerbations of symptoms, then spontaneously resolves over several weeks to months. Recurrent episodes are reported in half of the patients. Muscles commonly affected are the vastus lateralis, thigh adductors, and biceps femoris; but calf muscles may be involved as well. Active pathologic changes in the muscle are more sensitively evaluated with T2-weighted sequences on magnetic resonance (MR) imaging, which shows high intensity in involved muscle. Histologic features of DMI consist of large areas of muscle necrosis and edema. Regenerating muscle fibers and lymphocytic interstitial infiltration may be present. CONCLUSION: Diabetic muscular infarction is a rare complication of diabetes mellitus. In most patients, the diagnosis can be made when the characteristic clinical presentation is combined with a typical MR imaging results. Muscle biopsy can be helpful in establishing the diagnosis of DMI, but histologic findings are not specific. Awareness of this syndrome plus MR imaging as the first diagnostic test should lead to the correct diagnosis and shorter hospitalization.

Successful treatment of neuropathies in patients with diabetes mellitus.

OBJECTIVES: To report and characterize two forms of disabling progressive peripheral neuropathy in patients with diabetes mellitus, which respond to anti-inflammatory and/or anti-immune treatment. DESIGN: Review of clinical, electrophysiologic, and pathologic findings and results of treatment. SETTING: University medical center. PATIENTS: Twenty-one patients with diabetes mellitus to whom we gave anti-inflammatory and/or anti-immune treatment for progressive peripheral neuropathy during the past 6 years. MAIN OUTCOME MEASURES: Patients were interviewed and examined at intervals before and after beginning treatment with intravenous immunoglobulin (n = 15), prednisone (n = 13), cyclophosphamide (n = 5), plasma exchange (n = 3), and azathioprine (n = 1) (alone or in combination). RESULTS: Fifteen patients had evidence of axonal neuropathy by electrophysiologic studies (group A). All 15 patients had non-insulin-dependent diabetes mellitus, 10 patients had weight loss, and 13 patients had prominent involvement of thighs and/or thoracic bands consistent with diabetic amyotrophy or mononeuropathy multiplex. Small vessel disease was seen in all 10 patients who underwent biopsy, with perivascular or vascular inflammation seen in seven patients. Six patients had demyelinating neuropathy by electrophysiologic criteria (group B). All these patients had insulin-dependent diabetes mellitus, and no one had weight loss. The process was asymmetric in three patients and involved thoracic or abdominal regions in two patients. Onion bulbs were seen in all four patients who underwent biopsy, but no vascular inflammation or occlusion was seen. In all patients in both groups, worsening of their conditions stopped and improvement started after beginning treatment. CONCLUSION: Neuropathies responsive to anti-inflammatory and/or anti-immune therapy in patients with diabetes mellitus include (1) multifocal axonal neuropathy caused by inflammatory vasculopathy, predominantly in patients with non-insulin-dependent diabetes mellitus, indistinguishable from diabetic proximal neuropathy or mononeuropathy multiplex, and (2) demyelinating neuropathy indistinguishable from chronic inflammatory demyelinating polyneuropathy, predominantly in patients with insulin-dependent diabetes mellitus.

Lymphomatous polyneuropathy. Biopsy of clinically involved nerve and successful treatment.

We present a patient with large-cell lymphoma in remission who, over several weeks, developed widespread multifocal polyneuropathy. There was involvement of all four limbs, most severely the left upper extremity that had become useless. Biopsy of the left saphenous nerve within an area of sensory loss showed lymphoma in the endoneurium. There was no other evidence of recurrent lymphoma despite extensive investigation, including bone marrow, lumbar puncture, magnetic resonance imaging of the spine, and computed tomography of the abdomen and pelvis. Intensive systemic chemotherapy was accompanied by nearly complete recovery. Biopsy of a symptomatic nerve is preferable to routine sural nerve biopsy in this condition because of its patchy distribution. Treatment with systematic chemotherapy can be effective.

Myasthenia gravis presenting as weakness after magnesium administration.

We studied a patient with no prior history of neuromuscular disease who became virtually quadriplegic after parenteral magnesium administration for preeclampsia. The serum magnesium concentration was 3.0 mEq/L, which is usually well tolerated. The magnesium was stopped and she recovered over a few days. While she was weak, 2-Hz repetitive stimulation revealed a decrement without significant facilitation at rapid rates or after exercise, suggesting postsynaptic neuromuscular blockade. After her strength returned, repetitive stimulation was normal, but single fiber EMG revealed increased jitter and blocking. Her acetylcholine receptor antibody level was markedly elevated. Although paralysis after magnesium administration has been described in patients with known myasthenia gravis, it has not previously been reported to be the initial or only manifestation of the disease. Patients who are unusually sensitive to the neuromuscular effects of magnesium should be suspected of having an underlying disorder of neuromuscular transmission.

Biopsy-proven cerebral vasculitis associated with cocaine abuse.

We report cerebral vasculitis in 2 cocaine users who developed symptoms (transient blindness and persistent headache) while smoking "crack," followed by progressive widespread cerebral dysfunction with focal signs over the next few weeks. One patient had smoked crack exclusively, and the other also used cocaine intravenously. Sedimentation rates were elevated and HIV titers negative. Arteriography was normal in 1 patient and in the other showed multiple large-vessel occlusions without beading. Brain biopsy showed vasculitis involving small vessels in both patients. Multinucleated cells were present in the neuropil, but there were no granulomas or evidence of infection. One patient improved significantly with corticosteroid treatment, and made a good recovery. The other died despite corticosteroid and cyclophosphamide treatment.