ESPE Abstracts (2018) 89 P-P2-033

Quantitative Ultrasound Evaluation in a Cohort of 43 Young Adults with Classical CAH due to 21-Hydroxylase Deficiency (21OHD): Is Bone Mineral Quality Impaired?

Federico Baronio, Antonio Balsamo, Rita Ortolano, Nicoletta Massaccesi, Ilaria Bettocchi, Maximiliano Zioutas, Giulio Maltoni, Stefano Zucchini & Alessandra Cassio

S. Orsola-Malpighi University Hospital, Pediatric Unit, Center for Rare Endocrine Diseases (CARENDO BO), Bologna, Italy

Background: In young adults patients (pts) with CAH due to 21OHD few and conflicting data have been reported on bone mineral quality (BMQ) evaluated by quantitative ultrasound (QUS).

Objective and hypotheses: To evaluate the bone mineral status by QUS variables assessed at proximal phalanges of the hand in a cohort of young adults with classical CAH due to 21OHD and the possible associations with their clinical and metabolic features.

Method: We retrospectively evaluated QUS variables (Amplitude Dependent Speed of Sound - AD-SoS and Bone Transmission Time – BTT, expressed as z scores) measured at a mean age of 21.0±5.0 years, height SD, BMI SD, mean glucocorticoid + mineralocorticoid (GC+MC) equivalent dose of last 3 years, metabolic control (the patients were classified as in good (G), scarce (S) and excessive (E) control by means of 17 OH progesterone (G: <60 nmol/l;) and Androstenedione levels (S: >9 nmol/l; E:<0.5 nmol/l) at last evaluation), of 43 young adult 21 OHD-CAH pts (21 F and 22 M; 30 salt wasting and 10 simple virilizing forms), diagnosed and treated at our Pediatric Endocrinology Unit in the last 40 years.

Results: No patient showed QUS variables <−2.0 S.D. 10/43 pts (23%) (group A) showed slightly reduced AD SoS (−1.47±0.3) and BTT (−1.44±0.9); in the other 33 pts (group B) mean AD SoS (0.0±0.9) and BTT (−0.9±1.0) were within normal range. In group A and group B, age at evaluation of QUS (19.1±2.3 vs 21.8±5.7), height SD (−1.2±2.6 vs −1.1±1.0), BMI SD (0.66±0.9 vs 0.45±1.1), GC equivalent dose (16.2±2.6 vs 17.8±5.0) were not significantly different. In Group A 2/10 (20%) and in group B 12/33 (36%) pts. showed scarce metabolic control (P<0.01). Linear regression analysis showed negative correlation of AD-SoS with BMI SDS (P<0.01).

Conclusion: BMQ evaluated by QUS did not result severely impaired in our group of patients. Prospective studies are needed to confirm the possible correlation between QUS variables, long term metabolic control and BMI SD in young adults with classical CAH due to 21 OHD.