A rare case of isolated myocysticercosis of the arm: a case report and literature review.

INTRODUCTION AND

IMPORTANCE

Isolated myocysticercosis is a rare manifestation of cysticercosis, where a single cysticercus infests an individual skeletal muscle. We present a case of an isolated myocysticercosis in the forearm to highlight the atypical presentation, the diagnostic challenges, and the management options.

CASE PRESENTATION: A 25-year-old lady presented with a 2 × 2 cm swelling over the anterolateral aspect of her right forearm for 3 months, which was firm, non-fluctuant, and fixed to the underlying muscle but not the skin. She had no history of eating pork or being around pigs. An ultrasound revealed a well-defined cystic nodule. The magnetic resonance imaging (MRI) scan suggested myocysticercosis or vascular malformations as the two differentials, following which the cyst was surgically removed and the histopathological examination confirmed myocysticercosis. Additional screening MRI imaging revealed no lesions in the brain or the eyes.

CLINICAL DISCUSSION: The life cycle of Taenia involves two stages: larval (cysticerci) and adult (tapeworm) in two different hosts. Cysticercosis differs from taeniasis as humans become accidental intermediate hosts by ingesting tapeworm eggs, leading to cyst formation, commonly in the brain, orbit, subcutaneous tissue, or muscles. While treatment usually involves albendazole or praziquantel, our patient was managed with surgical excision due to the isolated nature of the cyst and diagnostic dilemma.

CONCLUSION

This case demonstrates that histopathological examination remains the cornerstone for the diagnoses of any parasite lesion where the clinical and radiological findings are dubious. Isolated myocysticercosis can be treated with surgical excision alone.