Importance of early recognition of amyotrophic lateral sclerosis-like disorders in the Egyptian population

Abstract

Background Early stages of amyotrophic lateral sclerosis (ALS)-like syndrome when only one limb is affected can be missed by physicians suggesting other unrelated disorders especially with evidenced concomitant pathology of the same limb, leading to diagnostic pitfalls and unnecessary procedures. Objective The aim of this study was to support the diagnosis of early stages of ALS-like disorders in clinically suspected patients by electrophysiological studies (EDX) including segments that may be clinically unaffected, and searching for the possible etiology. Patients and methods This study was conducted on 120 adult patients with unilateral limb symptoms associated with irrelevant imaging abnormalities. Diagnostic workup included history taking, general and neurological examination, and EDX using the El Escorial diagnostic criteria. Further investigations included laboratory studies and paraneoplastic and hormonal assays. Results Motor nerve conduction studies revealed reduced amplitude of compound muscle action potential in 62.5% of patients, borderline conduction velocities, normal distal latencies, conduction block in one case, and normal sensory nerve conduction studies. Electromyography of the cranial, cervical, lumbosacral, and dorsal segments showed acute denervation in 80% of patients and chronic denervation in all segments in 35% and in three body segments in 65% of patients. Laboratory investigations revealed 50.83% of patients with chronic hepatitis C, with significant statistical association between EDX and laboratory results, 30.83% with hyperthyroidism, 8.33% with paraneoplastic syndrome, one case with multifocal motor neuropathy with conduction block, one case with myasthenia gravis, and 8.3% with negative results. Conclusion ALS-like disorder should be investigated whenever ALS is suspected, and further laboratory workup might unveil a coexisting ‘possibly causative’ pathological condition.