A 25-year-old man, married for 4 years, presented with infertility. A physical examination showed normal secondary sexual characteristics, an undescended right testis and a 4r4 cm left testicular mass, with a palpable single left vas deferens. He had no other obvious congenital anomalies. The patient was investigated to exclude left testicular tumour and to locate the right testis. Semen analysis revealed azoospermia, which together with elevated FSH and LH levels, suggested primary testicular failure. Ultrasonography of the left testis showed two fused homogenous solid masses, raising the clinical suspicion of a crossed ectopic testis ( Fig. 1). A complete blood count, electrolytes, creatinine, liver function tests, urine culture and tumour markers (AFP and bhCG, 6 kIU/L and 2 IU/L, respectively) were all normal. CT of the abdomen showed a normal-size spleen in the left hypochondrium, with other normal abdominal viscera and a normal-size right testis lying in the inguinal canal. At exploratory surgery, there was an encapsulated mass arising from the upper pole of the left testis within the tunica albuginea. Frozen-section analysis of the mass was reported as splenic tissue, consistent with splenogonadal fusion. The splenic mass was excised, preserving the left testicular tissue from which a biopsy was taken. Histological examination of the mass con®rmed normal splenic tissue, composed of red and white pulp elements and ®brous capsule (Fig. 2). The left testicular biopsy showed no evidence of spermatogenesis. The right testis was located laparoscopically as a secondstage procedure and this con®rmed an intra-abdominal testis of suf®cient volume at the internal inguinal ring. A right orchidopexy was performed; a right testicular biopsy showed features consistent with postpubertal cryptorchidism and no evidence of malignancy. CommentsThis patient represents a rare case of left splenogonadal fusion with a right undescended testis and associated primary male infertility. To our knowledge, no other case has been reported of an association of splenogonadal fusion with primary male infertility. This congenital