Introduction: The hCG stimulation test is a useful indicator of functional testicular tissue and may also have a place in treating undescended testes (UDT). However, its utility is limited by the inconsistency in the regimens used. We have looked at the clinical and biochemical response in a group of children with UDT who had a prolonged hCG stimulation as part of their clinical management.
Methods: The retrospective review in 17 cases with a median EMS (10th, 90th centiles) of 9 (5.6, 10.5) included analysis of age, pre and post hCG - serum concentrations of testosterone (T), DHT and androstenedione (A). These 17 cases included one child who was later discovered to be 46XX and another who was anorchic. These were both excluded when assessing clinical outcome by palpation of testes and the need for orchidopexy.
Results: Amongst the 17 cases, all except one had serum testosterone measurements on D1, 4 and 21, as per the protocol. 9, 15 and 16 patients had a pre and a post DHT, A and SHBG, respectively. Testicular descent occurred in 8/26 (32%) undescended testes. As a result, immediate surgery was deemed unnecessary in 7/15 (47%) cases. Three patterns of changes in serum T were noticed; in 4/17 (24%), the expected rise in T was by D4, in 6/17 (35%) the rise was by 21 and not D4 and in the remainder, serum T stayed low. The median D1 T:A rose from 0.4 (0.2, 1.6) to 1.9 (0.3, 4.8) at D4 (P<0.01). There was no further rise in the ratio by D21. The median DHT:T at D1 and D4 remained unchanged at 0.26 (0.06, 0.4) and 0.26 (0.2, 0.66), respectively.
Conclusion: Prolonged hCG stimulation not only helps to establish the presence of functioning testicular tissue and determine abnormalities in testosterone biosynthesis, but it may also reduce the need for orchidopexy.