Trichinellosis Masquerading as a Soft-Tissue Mass: A Case Report.

Abstract

Trichinellosis, also known as trichinosis and trichiniasis, is a rare infection caused by the ingestion of raw or undercooked meat containing viable encysted larvae of the parasitic roundworm Trichinella species1-3. Previously quite common, the Centers for Disease Control and Prevention currently report only a few trichinellosis cases annually in the United States2,4. The scarcity of present-day cases is largely attributed to increased federal legislation over the past several decades that led to many public health measures to educate people regarding techniques for safe food preparation2,4-6. Trichinellosis usually presents acutely with circumorbital edema, fever, myalgia, and abdominal discomfort. We report a case in a fifty-seven-year-old woman who presented atypically with a soft-tissue mass in the forearm. Clinical presentation, diagnosis, prevention, and treatment of this rare infection are discussed. The patient was informed that data concerning her case would be submitted for publication, and she provided consent. A fifty-seven-year-old woman presented to the orthopaedic oncology service for evaluation of a painless mass in the left forearm, which had been slowly enlarging over several years. The patient's rheumatoid arthritis had caused finger deformities and diffuse rheumatoid nodules. At the time of presentation, the rheumatoid arthritis was being treated with abatacept, a T-cell costimulation modulator, but in the past it had been treated with other disease-modifying antirheumatic drugs. Additionally, she had a twenty-year history of anterior interosseous nerve syndrome of the right forearm, and a one-year history of anterior interosseous nerve syndrome of the left forearm, although the cause of these bilateral syndromes was unknown. Physical examination demonstrated a firm, fixed, painless mass on the volar side of the left forearm, proximal to the wrist crease. The patient had an absence of flexor pollicus longus and flexor digitorium profundus function …