Rhabdomyolysis caused by peripheral T-cell lymphoma in skeletal muscle

We report a rare case of rhabdomyolysis caused by peripheral T-cell lymphoma (PTCL) in skeletal muscle. A 62-year-old man was admitted with complaints of sudden muscle weakness. Laboratory abnormalities were identified including markedly elevated creatinine-phosphokinase, peaking at 62,640 IU/L and serum creatinine (Cr) at 5.0 mg/dL. Computed tomography scans revealed tumorous swelling of the right psoas major muscle and the obturator internus muscles. Consequently, he was diagnosed with acute renal failure caused by rhabdomyolysis and was treated with hydration and continuous hemodiafiltration, which resulted in significant improvement in renal function (Cr 1.79 mg/dL). However, the cause of the rhabdomyolysis remained unclear, and he suddenly developed a remittent fever and suffered from hemophagocytic syndrome. Serum ferritin level dramatically increased to 104,707.0 ng/mL and creatinine level to 4.09 mg/dL. We performed a biopsy of inguinal lymph nodes, leading to a diagnosis of PTCL. Finally, he was diagnosed with rhabdomyolysis caused by PTCL. Methylprednisolone pulse therapy markedly improved his general condition and renal function (Cr 1.48 mg/dL), and computed tomography scans revealed that tumorous swelling was greatly diminished. Except when the cause of rhabdomyolysis is readily apparent, such as in cases of trauma, drug and thrombophlebitis, one should consider that rhabdomyolysis may be a sequel of lymphoma.