[Diagnostic value of muscle, sural nerve and skin biopsies in childhood neuromuscular disorders].

Objective: To elicit the usefulness of muscle, sural nerve and skin biopsies in neuromuscular disease, including its diagnostic value and indications for biopsy.

Method: The authors retrospectively evaluated the clinical data of every patient who underwent muscle, sural nerve and/or skin biopsy in the department between January 1999 and December 2004.

Result: One hundred and two patients with the suspected neuromuscular diseases were included. Muscle disease or hereditary metabolic/degenerative diseases with muscular injury were suspected in 82 patients, specific or typical histological findings confirmed diagnosis in 33 of these patients. The diagnosis included muscular dystrophies in 13 patients; inflammatory myopathies in 4 patients; congenital centronuclear myopathies in 2 patients; vacuole myopathy in 1 patient; mitochondrial myopathies in 8 patients; lipid storage myopathy in 1 patient; glycogenosis in 1 patient; spinal muscular atrophy in 3 patients. Nonspecific changes were seen in 25 patients, and in 24 patients nothing abnormal was revealed. Neuropathy or hereditary metabolic/degenerative diseases with peripheral nerve injury were suspected in 23 patients, specific or typical histological findings confirmed diagnosis in 10 of these patients, including hereditary motor and sensory neuropathy in 9 patients and metachromatic leukodystrophy with peripheral nerve abnormality in 1 patient. Nonspecific changes were seen in 11 patients and 2 patients had normal sural nerve. Skin biopsies were performed in 8 patients, specific or typical histological findings confirmed diagnosis in 4 of these patients. The diagnosis included neuronal ceroid lipofuscinosis in 2 patients, infantile axonal dystrophy in 1 patient, vacuole lysosomal disease in 1 patient, and 4 patients had normal skin biopsy.

Conclusion: Muscle, sural nerve and skin biopsies play an important role in diagnosis of childhood neuromuscular disease, and should be done only in carefully selected cases after thorough clinical work-up. Muscle biopsy is essential for diagnosis of congenital and metabolic myopathies. Typical pathologic alterations of sural nerve have diagnostic value for hereditary neuropathies. Skin biopsy should be performed to verify neuronal ceroid lipofuscinosis.