Prevalence of steroid sulfatase deficiency in California according to race and ethnicity

Objective Estimate steroid sulfatase deficiency (STSD) prevalence among California's racial/ethnic groups using data from a previous study focused on prenatal detection of Smith-Lemli-Opitz syndrome (SLOS). SLOS and STSD both have low maternal serum unconjugated estriol (uE3) levels. Methods Prevalence was estimated using three steps: listing clinically identified cases; modeling STSD frequency at three uE3 intervals using diagnostic urine steroid measurements; applying this model to determine frequency in pregnancies not providing urine. Results Overall, 2151 of 777 088 pregnancies (0.28%) were screen positive; 1379 of these were explained and excluded. Fifty-four cases were diagnosed clinically among 707 remaining pregnancies with a male fetus. Urine steroid testing identified 74 additional STSD cases: 66 (89.2%) at uE3 values <0.15 MoM, 8 (10.8%) at 0.15-0.20 MoM, and 0 (0%) at >0.20 MoM. Modeling estimated 107.5 STSD cases among 370 pregnancies without urine samples. In males, STSD prevalence was highest among non-Hispanic Whites (1 : 1230) compared to Hispanics (1 : 1620) and Asians (1 : 1790), but differences were not significant. No STSD pregnancies were found among 65 screen positive Black women. Conclusion The overall prevalence estimate of 1 : 1500 males is consistent with published estimates and is reasonable for counseling, except among Black pregnancies where no reliable estimate could be made. Copyright (C) 2010 John Wiley & Sons, Ltd.