Dados do Trabalho

Título

Tubular Aggregate Myopathy with Rhabdomyolysis: An Uncommon Presentation in Elderly Male

RESUMO

Case report
A 76-year-old male with acute symmetrical inferior limbs weakness and pain. No previous history of muscle weakness. Denied alcohol intake, prior exercise intolerance, fatigue, myoglobinuria, ptosis, or pigmenturia, as well as worsening after periods of fasting. History of systemic arterial hypertension and dyslipidemia. He had been treated with the same dose of simvastatin and antihypertensives. Furthermore, no relevant familial history of consanguinity. On examination, the strength of proximal inferior limbs graded MRC grade IV. Neoplastic, infectious, rheumatological, and endocrinology diseases were ruled out. Initial CK = 6.719U/L. Muscle MRI revealed a heterogeneous edema pattern, with predominant proximal impairment. No evidence of atrophy was detected. Statins were promptly withdrawn. After 5 to 7 days, CPK lowered to normal level and muscle biopsy confirmed Tubular Aggregates Myopathy. There was a complete improvement of muscle weakness after 30 days.

Discussion
Tubular Aggregate Myopathy is a rare disorder of unknown prevalence. The symptoms and severity are widely heterogeneous, and the diagnosis is based on a history of progressive loss of strength and/or muscle pains, muscle biopsy revealing tubular aggregates, and absence of another neuromuscular disease. The Tubular Aggregate Myopathy can present as a pseudo metabolic feature, without progressive weakness, mimicking the metabolic myopathies.

Final comments
Tubular Aggregate Myopathy is a rare and an inherited disorder and, differently from metabolic myopathies, is characterized by slowly progressive proximal muscle weakness, cramps and myalgia. Muscle biopsy usually points to tubular aggregates of variable morphology and type II fibers atrophy.

Palavras Chave

Myopathy, neuromuscular disorders