Neuromuscular manifestations in hereditary haemochromatosis.

Involvement of peripheral nerves and skeletal muscles has been reported in the course of hereditary haemochromatosis (HH) but a systematic study is lacking. However, patients with HH report symptoms suggesting a possible polyneuropathy or myopathy. In this study patients with DNA proven HH were recruited from a large general teaching hospital. First, all patients were clinically examined using a structured interview and neurological exam. After reviewing these data an expert panel reached consensus about the presence of a possible neuropathy or myopathy and made recommendations for ancillary investigations (nerve conduction studies, electromyography, thermal threshold tests, laboratory tests). After a second meeting consensus was reached about the final diagnosis. Patients who had a neuropathy or myopathy of which the origin was still unclear were referred to an independent neurologist for further evaluation. Ultimately, of 46 patients included, 25 had no myopathy or neuropathy, 5 an axonal sensory motor polyneuropathy of which the cause was found (diabetes in 2, combination of diabetes and chemotherapy in 1, Charcot Marie Tooth type 2 in 1, Morbus Sjögren in 1), 9 an idiopathic axonal sensory motor polyneuropathy, 3 an idiopathic small fiber polyneuropathy and 4 a carpal tunnel syndrome. There were no cases of proven myopathy. We conclude that an idiopathic polyneuropathy was diagnosed in a relative large number of patients with HH (26%), but the causal relationship needs to be confirmed in larger (case-control) series.