Mazen M. Dimachkie

Peripheral nerve injury after brief lithotomy for transurethral collagen injection

Two patients with prior prostate surgery sustained peripheral nerve injuries after transurethral collagen injection for the treatment of urinary incontinence. In the first patient, brief lithotomy positioning caused a gluteal compartment syndrome and sciatic neuropathy. In the second patient, obturator neuropathy was due to leakage of collagen along the course of the obturator nerve. This is the first report of peripheral nerve injury in patients undergoing transurethral collagen injection.

Phenytoin-Induced Dermatomyositis: Case Report and Literature Review

A muscle biopsy done to evaluate for ragged red fibers in a patient with progressive myoclonic epilepsy unexpectedly showed prominent inflammation and perifascicular atrophy. Brain biopsy demonstrated Lafora bodies. Lafora body disease is a progressive, fatal myoclonic epilepsy presenting usually in the first or second decade with mental regression, generalized and myoclonic seizures,1,2 ataxia, spasticity, and involuntary movement. It is an autosomal recessive3 disorder localized to chromosome 6q. Phenytoin is herein implicated in the pathogenesis of dermatomyositis.

Exercise intolerance associated with a novel 8300t>C mutation in mitochondrial transfer RNAlys

Mutations in the mitochondrial genome contribute to the pathophysiology of many neuromuscular diseases. Recently there has been an increased appreciation of the role of mitochondrial DNA (mtDNA) mutations in the etiology of exercise intolerance. Using TTGE (temporal temperature‐gradient gel electrophoresis) and sequence analyses of the entire mitochondrial genome, we identified a novel heteroplasmic mutation (8300T>C) in the tRNAlys gene (MTTK) from a patient with unexplained exercise intolerance. The mutation was present in blood, hair, and muscle, with the highest percentage of heteroplasmy found in muscle. The results of muscle respiratory chain enzyme analysis are consistent with tRNA mutation. These data suggest that this novel mutation is yet another mtDNA mutation associated with muscle disease and should be considered in patients with similar symptoms. Muscle Nerve, 2006

Benign monomelic amyotrophy of the lower extremity: report of two cases and literature review.

Benign monomelic amyotrophy is an uncommon cause of progressive mildly disabling atrophy and weakness of a limb. It predominantly affects the distal upper limb of young men. We present two women with benign monomelic of amyotrophy of the lower extremity. Although thedisorder seemed clinically confined to a leg, we confirmed by electromyography chronic denervgation of the contralaterral extremity of both patients and in the arm of one patient.We review the literature and discuss the differential diagnosis. Benign monomelic amyotrophy is a diagnosis of exclusion that requires consideration in young women with unilateral leg atrophy.

Review process for IVIg treatment: Lessons learned from INSIGHTS neuropathy study

Background This project is an effort to understand how orders for IV immunoglobulin (IVIg) are documented and prescribed by physicians, and subsequently, how they are reviewed by insurance companies for the treatment of immune neuropathies. Methods A panel of neuromuscular specialists reviewed case records from 248 IVIg-naive patients whose in-home IVIg infusion treatment was submitted to insurance for authorization. After reviewing a case record, 1 panelist was asked to make a diagnosis and to answer several questions about the treatment. A second panelist reviewed the original record and follow-up records that were obtained for reauthorization of additional treatments and was asked to determine whether the patient had responded to the treatment. Results Our specialists believed that only 32.2% of 248 patients had an immune neuropathy and were appropriate candidates for IVIg therapy, whereas 46.4% had neuropathies that were not immune mediated. Only 15.3% of cases met electrodiagnostic criteria for a demyelinating neuropathy. Our specialists believed that 36.7% of 128 cases with follow-up records had responded to therapy. In cases in which the initial reviewer had predicted that there would be a response to IVIg, the second reviewer found that 54% had responded. This is compared with a 27% response rate when the first reviewer predicted that there would be no response (p = 0.019). Conclusions Our expert review finds that the diagnosis of immune neuropathies made by providers, and subsequently approved for IVIg therapy by payers, is incorrect in a large percentage of cases. If payers include an expert in their review process, it would improve patient selection, appropriate use, and continuation of treatment with this expensive therapeutic agent.

Calf compartment syndrome and lumbar plexopathy following topical bovine thrombin-induced coagulopathy.

We describe a patient with acquired thrombin inhibitor who developed tibial and peroneal neuropathies followed by lumbar plexopathy as a result of large calf and psoas muscle hematomas. Thrombin time, Prothombin time, and partial thromboplastin time were prolonged after repeated exposures to topical bovine thrombin in two orthopedic procedures Specific coagulation tests revealed that the coagulopathy was the result of an inhibitor to bovine thrombin that cross-reacted with human thrombin. We emphasize the risk of spontaneous hematomas that can compromise peripheral nerves as a result of an acquired coagulopathy following bovine thrombin exposure.