Hyperandrogenaemia such as that seen in Polycystic Ovarian Syndrome (PCOS) is a common presentation in women of reproductive age. However, PCOS is a diagnosis of exclusion and late-onset congenital adrenal hyperplasia (CAH) and rarely androgen-secreting tumours (AT) need to be considered. Dihydrotestosterone (DHT) may help to differentiate these groups of women with hyperandrogenism. Increased 5-alpha reductase activity has been reported in PCOS.
Serum “androgen profile” which includes Testosterone (T), DHT, Androstenedione and 17-Hydroxyprogesterone by LCMSMS Xevo TQ-S (Waters Corporation, Milford, MA) with prior liquid-liquid phase extraction is offered at PathWest QEII for biochemical investigation of women with hyperandrogenism. An audit was undertaken on all androgen profiles requested from 1st January 2016 to 1st January 2018. Results from women above the age of 16 with T ≥2.0 nmol/L in the follicular phase were grouped according to clinical diagnoses of PCOS, CAH or AT. Women on oral contraceptive pills and Testosterone therapy were excluded. A total of 106 patients were analysed: 84 with PCOS (79.2%), and 11 each (10.4%) with CAH or AT.
Serum DHT was increased in 16 patients with PCOS (19%), 4 with CAH (36.3%) and 5 with AT (45.4%). After adjustment for age, T was significantly lower in both PCOS (p=0.001) and CAH (p=0.008) compared to those with AT. Serum DHT was also significantly lower in both PCOS (p=0.005) and CAH (p=0.004) subjects than those with AT. The median ratio of T:DHT in PCOS was lower than CAH and AT.
Both T and DHT were significantly higher in the AT group than the PCOS or CAH group. The evidence of a lower T: DHT ratio was demonstrated in PCOS group compared to CAH or AT group, which suggests increased 5-alpha reductase activity in PCOS women.