患者，男，72岁，河南南阳人，常住深圳市，有以蚯蚓为诱饵钓鱼的习惯。2023年因胃癌接受胃切除术，在例行电子胃镜复查时发现空肠部位有线虫寄生，但是无典型呼吸道及消化系统临床表现。血常规检查显示，白细胞数为6.61 × 10⁹/L，嗜酸粒细胞百分比为0.7%，嗜酸粒细胞绝对值为0.05 × 10⁹/L，各项指标均在正常范围内。以活检钳取出虫体。虫体呈红色，细长且呈不典型“Y”字型，长度约10 mm，可自主活动。虫体经哈瑞氏苏木素染液处理，在光学显微镜下鉴定为兽比翼线虫（Mammomonogamus）雄虫。患者被诊断为兽比翼线虫感染，采用口服阿苯达唑（400 mg/d，每日1次，疗程为1周）治疗。治疗后1周，患者粪便中未检测到兽比翼线虫虫卵。

The patient was a 72-year-old male from Nanyang, Henan Province, with a permanent residence in Shenzhen City, who had a habit of fishing using earthworms as baits. He underwent a gastrectomy for gastric cancer in 2023, and nematodes were found parasitizing the jejunum during a routine electronic gastroscopic follow-up; however, but no typical clinical manifestations of respiratory or digestive system were observed. Routine blood tests showed a white blood cell count of 6.61 × 10⁹/L, an eosinophil percentage of 0.7%, and an absolute eosinophil count of 0.05 × 10⁹/L, with all indicators within the normal range. The nematodes were removed using biopsy forceps, appearing red, slender, and atypical in shape with a “Y” configuration, measuring approximately 10 mm in length and capable of autonomous movement. Following staining with Harris’s hematoxylin, the nematodes were identified as male Mammomonogamus under an optical microscope. The patient was diagnosed with Mammomonogamus infection and orally administered with albendazole (400 mg/d, once daily for one week). No Mammomonogamus eggs were detected in the patient’s stool samples one week post-treatment.