Fenofibrate-induced rhabdomyolysis in a patient with chronic kidney disease: an unusual presenting feature of hypothyroidism / Rabdomiólise induzida por fenofibrato em paciente com doença renal crônica: uma apresentação clínica incomum do hipotireoidismo

Clinical and most often moderate skeletal muscle involvement is a frequent problem in adults with hypothyroidism, and includes a number of different manifestations. Severe involvement with rhabdomyolysis, however, is very rare, and only a few cases have been reported to date, most of them with an additional factor of muscle injury. We described a patient with stage 3 chronic kidney disease who presented with rhabdomyolysis while taking fenofibrate, and was found to have hypothyroidism. We also highlighted the importance of excluding the diagnosis of thyroid dysfunction before treatment with lipid-lowering agents.

Manifestações musculoesqueléticas variadas e de moderada intensidade são comuns em adultos com hipotireoidismo. No entanto, o envolvimento muscular grave, caracterizado por rabdomiólise, é incomum. Até o momento, poucos casos foram descritos na literatura, e a maior parte deles em associação com um fator adicional de dano muscular. Descrevemos um paciente com doença renal crônica (estádio 3) que se apresentou com rabdomiólise durante o tratamento com fenofibrato e cuja investigação adicional evidenciou hipotireoidismo primário. Enfatizamos, ainda, a importância da exclusão de disfunção tireoidiana antes de iniciar terapia com agentes hipolipemiantes.

Comparative ultrastuctural study of the effect of simvastatin [Zocor] and fenofibrate [Lipanthyl] on skeletal muscle of albino rats

This study aimed to detect the effect of Zocor [example of statins] and Lipanthyl [example of fibrates] on the skeletal muscle of male albino rats at the ultrastructural level. For this purpose sixty male albino rats were encountered and were subdivided into five groups. G1 was the control group [20 rats]; and other four groups 10 rats each. G2 received Zocor 0.72 mg/200 mg orally equivalent to the therapeutic dose in adult human and G3 received Lipanthyl 5.4mg/200g orally equivalent to the therapeutic dose in adult human. G4 was the recovery from Zocor intake and G5 was the recovery from Lipanthyl intake. For each group both semithin and ultrathin sections of LS of skeletal muscle were examined. Measurements of the myofibril diameters, average mitochondrial diameters in addition to the counting of the mitochondrial number were done using the image analyzer. The ultrastructural findings in G2 included marked myofibril degeneration in the form of loss and distortion of myofibrils. Mitochondria showed significant decrease in their number and very highly significant increase in their diameters. The nuclei of the muscle fibers appeared either swollen or shrunken, while those of satellite cells appeared shrunken and heterochromatic. G3 demonstrated a mixture of both degenerative and repair processes. The nuclei of satellite cells appeared either heterochromatic or euchromatic. There were focal loss of the myofibrils with very highly significant increase in the mitochondrial number and dilated sarcoplasmic reticulum. G4 showed highly significant decrease in the myofibril diameters compared to the control with the regaining of continuity and organization. G5 demonstrated non significant decrease in the myofibril diameter compared to the control. The present study concluded that Zocor had more damaging effect on skeletal muscle than Lipanthyl. Fortunately these myofibril changes were reversible after the stop of the drugs. It also concluded that the choice of hypolipidemic therapy needs to be based not only on the outcome evidence and cost-effectiveness analysis, but also on safety considerations for the individuals

Fenofibrate-induced myopathy.

Fenofibrate induced myopathy is a rare adverse event. We present a case of muscle pain and quadriparesis following administration of 200mg of fenofibrate for 35 days. Patient gradually improved after stopping the drug. As per our knowledge, this is probably the first case report of fenofibrate induced myopathy from India.