Mitochondrial Myopathy or Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)?-Reply

Abstract

In Reply. —Krendel supposes that the patient whom we described 1 might have been suffering from chronic inflammatory demyelinating polyneuropathy (CIDP). Initially, this disorder has ranked high in our differential diagnostic considerations and investigations (including sural nerve biopsy) were directed to confirm or exclude this condition. However, the combination of the clinical signs and the results of additional investigations, such as symmetric proximal muscle weakness, normal sensation, normal sensory action potentials and latencies, normal histologic appearance of the sural nerve, and the absence of relapse to date, features that are individually rarely encountered in patients with CIDP, has made us reject the diagnosis of CIDP. We have reviewed our patient's muscle biopsy specimens, and we persist in our opinion that the quadriceps muscle specimen shows evidence of lipid storage on Sudan black stain and electron microscopic studies. The soleus biopsy specimen, on the contrary, showed evidence of denervation consistent with