Lateral asymmetry of motor unit number estimate (MUNE).

The aspects of lateral asymmetry of the peripheral nervous system have been investigated to a lesser extent than the aspects of lateral asymmetry in the central nervous system. We utilized a statistical method of quantitative MUNE to demonstrate lateral asymmetry of the motor units in healthy individuals, revealing higher values in the nondominant hand. Awareness of this phenomenon will improve the accuracy and reliability of this MUNE method when used in clinical trials.

Toxoplasmic polymyositis revisited: case report and review of literature.

Toxoplasmosis can cause polymyositis either by reactivation or by recent infection. Inconsistent response to antiprotozoal therapy has been the strongest argument against toxoplasmic polymyositis as a separate entity. We report a biopsy-proven case of toxoplasmic polymyositis in a cardiac transplant patient presenting with a severe proximal weakness, myopathic, electromyographic changes and ten-fold increase of anti-Toxoplasma antibodies. An early antiprotozoal therapy and plasmapheresis led to recovery. A review of previously reported cases of toxoplasmic polymyositis suggests that an early antiprotozoal therapy is the most important variable affecting the outcome of this disease. We propose that toxoplasmic polymyositis has two phases: acute, responsive to antiprotozoal therapy, and chronic, manifested by altered immune response requiring steroids. We suggest that all patients presenting with polymyositis should have serological tests for toxoplasmosis as a part of their initial evaluation and an early trial of antiprotozoal therapy in case of positive findings.

Motor unit number estimate (MUNE) testing in male patients with mild to moderate carpal tunnel syndrome.

Carpal tunnel syndrome is a frequent clinical entity with an excellent prognosis if adequately treated. However, in rare cases of treatment failure, patients may suffer significant impairment of hand function with various degrees of disability. Loss of motor units in the hand muscles is the pathophysiological basis for this functional impairment. In our study we utilized motor unit number estimate (MUNE) testing in patients with mild to moderate carpal tunnel syndrome in an attempt to identify a patient population with a "silent" loss of motor units in the affected hand. As a result of the study we identified two groups of such patients; first, the group with an associated cervical radiculopathy, and second, the group with an increased amount of polyphasic motor units in the abductor pollicis brevis muscle on electromyographic (EMG) evaluation. Potentially, these patient populations are predisposed for functional impairment of the hand and, therefore, require a more active diagnostic and therapeutic evaluation. Our study also indicates that morphology of motor unit potentials is a good indicator of the motor unit reserve and correlates well with our MUNE results. MUNE testing proved to be a well tolerated, reliable and practical technique in the diagnosis, treatment and research of neuromuscular disorders.