Pancake kidney is a rare renal fusion anomaly. It is characterized by a lobulated renal mass located in the pelvic cavity consisting of two fused lateral lobes, usually has a separate pelvicalyceal system without an intervening septum. The estimated incidence is 1 in 65 000–375 000 individuals. Often it is associated with other genitourinary and vertebral anomalies. Meanwhile, undescended testis is one of the most common congenital anomalies of the male newborn child. The incidence is reported to be 1–4.5 in 100 full-term neonates. Here we reported a case where both the conditions coexist.

A 38-year-old man had a history of imperforate anus done diverting colostomy at birth and later correction with reversal of stoma, and a history of acute appendicitis done open appendicectomy at teen. He presented with vomiting for 5 days and epigastric pain for 2 days. Physical examination revealed a distended abdomen, with well healed left sided oblique scar and Lanz scar. Right testis was palpable in the scrotum but left testis was neither in the scrotum nor in the left inguinal area. A CECT abdomen was performed as initial workup where no mechanical obstruction was identified. Instead, the renal beds were empty where the kidneys were identified at L3-S1 levels with abnormal fusion of its inferior, mid and superior poles. It had separate ureters and veins, where both the veins draining into the right internal iliac vein. USG of the scrotum showed normal right testis and absence of left testis. Patient was observed in the ward and discharged well after symptoms relieved. On a later date, he underwent an elective laparoscopic converted to open left inguinal exploration in view of dense adhesion encountered while entering the peritoneum. The left spermatic cord was identified tracking down to the left external inguinal ring, ended with a testicular nubbin which was confirmed with HPE.

The theory of mechanical fusion suggests that the metanephric blastema of the two kidneys come in contact in the pelvis during the 4th week of gestation. Pancake kidney arises when the umbilical arteries press the nephrogenic primordia, and the kidneys fuse in the pelvis and do not ascend. It usually receives the blood supply from two main arteries and draining into two veins. USG can be useful for diagnosis and to establish the presence of the isthmus. CT and MRI can help in mapping the anatomy of the collecting system and vascular anatomy. Meanwhile, descent of the testes involves complex anatomical steps and hormonal regulation. The transabdominal descent occurs at 10–15 weeks of gestation while the inguinoscrotal descent occurs at 25-35 weeks. If rudimentary vessels and vas deferens can be seen, it suggests a case of testicular atrophy being a result of a prenatal testicular vascular accident. International guidelines do not recommend any diagnostic imaging. Laparoscopic orchidopexy has become the standard procedure in the management of nonpalpable undescended testes.

Pancake kidney is a rare developmental problem usually incidentally detected and asymptomatic. It is not necessarily associated with renal dysfunction but alterations of the excretory system predispose patients to recurrent urinary tract infections or obstructions. While undescended testis is a relatively common finding, early intervention can improve future fertility and reduce risk of malignancy. For these reasons patients should be informed of the condition and to receive appropriate follow-up.