ESPE Abstracts

Introduction: Monitoring steroid hormone levels of children with endocrine disorders, such as congenital adrenal hyperplasia (CAH) and disorders of sex development (DSD), can be challenging. Dried blood spot (DBS) sampling can be helpful for these patients. DBS sampling is less invasive, easier to sample, and simpler to transport and store compared to venous blood sampling. Additionally, DBS sampling can be done at home at any time of the day, thus improving patient convenience. In order to sample at home and send the DBS to the laboratory, the effect of storage and temperature on the stability of steroid hormones in DBS samples needs to be established.

Methods: DBS from 10 healthy volunteers (5 males, 5 females) were collected and stored per different temperature (-20°C, 4°C, room temperature, 37°C) for 7- and 14-days, and 3- and 6-months (DBS stored at 37⁰C were kept for maximal 7 weeks). Directly after sampling steroid hormone concentrations of cortisol, cortisone, corticosterone, testosterone, androstenedione, and 17-hydroxyprogesterone were assessed using our in-house LC-MS/MS method and were set at 100% (baseline). Steroid hormone concentrations were considered stable when the median shift stayed within ±10% from baseline.

Results: All steroids in DBS remained within ±10% change from baseline for up to three months when stored at -20⁰C and 4⁰C, except for cortisone concentrations which only remained <±10% change up to 14 days. At room temperature steroids remained <±10% change from baseline up to three months, except for androstenedione concentrations which only remained <±10% change up to 7 days, and cortisone concentrations up to 14 days. When stored at 37⁰C only testosterone concentrations remained <±10% change up to 7 weeks. 17-hydroxyprogesterone and corticosterone concentrations remained <±10% change up to 14 days, while androstenedione and cortisol concentrations only remained <±10% change up to 7 days. Cortisone concentrations already showed >±10% change at day 7 of storage.

Conclusions: In general, the steroid hormones cortisol, cortisone, corticosterone, testosterone, androstenedione, and 17-hydroxyprogesterone remain stable in DBS long enough to be send by regular mail to the diagnostic laboratory. Thus, self-sampling DBS at home could potentially be used for monitoring steroid hormone levels of children with endocrine disorders such as CAH or DSD.