X-linked recessive bulbospinal neuronopathy: a report of ten cases.

TLDR

Adult‑onset X‑linked recessive bulbospinal muscular atrophy presents with proximal limb weakness, cramps, hand tremor, facial and tongue involvement, gynaecomastia, infertility, and occasionally diabetes, as illustrated in ten patients from eight families. Electrophysiology showed normal motor conduction but reduced sensory potentials, while elevated creatine kinase and muscle biopsies revealed neurogenic atrophy with secondary myopathic changes, underscoring the need to recognize this distinctive disorder.

Abstract

A form of adult onset 9bulbospinal muscular atrophy9 of X-linked recessive inheritance is described in 10 patients from eight families. Muscle weakness in the limbs was mainly proximal and developed in the third to fifth decades of life, often preceded by muscle cramps on exertion and tremor of the hands. Weakness and fasciculation of the facial muscles and tongue were prominent. All the patients had gynaecomastia and some were infertile. Two had diabetes mellitus. Motor nerve conduction studies were normal but most patients had small or unrecordable sensory action potentials in the absence of clinical sensory loss. Plasma creatine kinase levels were considerably elevated and muscle biopsies showed neurogenic atrophy together with secondary myopathic changes. The importance of recognising this distinctive disorder in single cases (six of the present series) is emphasised.