TY - BOOK AU - Heba Yehia Ahmed Asfour AU - Heba Nabil Elbaz , AU - Marianne Fathy Morgan , AU - Yasmine Taha Elshiwy , TI - Identification of patients with 11Ý-hydroxylase deficiency among a group of patients of congenital adrenal hyperplasia with alleged 21-hydroxylase deficiency / PY - 2019/// CY - Cairo : PB - Heba Yehia Ahmed Asfour , KW - 11 Deoxycortisol KW - 21Deoxycortisol KW - Congenital adrenal hyperplase N1 - Thesis (Ph.D.) - Cairo University - Faculty of Medicine - Department of Clinical and Chemical Pathology; Issued also as CD N2 - Background: Elevation of 17 hydroxyprogesterone (17OHP) is an important marker in diagnosis of congenital adrenal hyperplasia (CAH) due to deficiency of 21 hydroxylase enzyme, but its is also elevated in 5-8% of patients due to deficiency of 11 beta hydroxylase enzyme.11 deoxycortisol is elevated in 11 beta hydroxylase deficient patients but it is not routinely done so unfortunately accurate diagnosis may be missed.The aim of this study was to measure 11 deoxycortisol to the patients with elevated 17OHP, once with radioimmunoassay (RIA) and then repeat it with LC-MS/MS and compare between both methods. Also, another steroid was measured; 21 deoxycortisol using LC-MS/MS to detect its ability to discriminate between both conditions and if it is more beneficial to measure multiple steroids simultaneously. Patients and Methods: Samples from 144 patients were measured for 11 deoxycortisol using RIA.Trials were done to measure 11 deoxycortisol, 17OHP and 21 deoxycortisol using HPLC but failed. Fifty-two samples were randomly selected and measured for the previous 3 parameters using LC-MS/MS. Results: 11 deoxycortisol measured by LC-MS/MS identified patients with 11 beta hydroxylase deficiency among those with 21 hydroxylase deficiency (p=0.002). Moreover, it was highly predictive of 11 beta hydroxylase deficiency at a cutoff {u2265} 11 ng/ml with 100 % sensitivity and 92.3% specificity. Simultaneous measurement of 21 deoxycortisol and 11 deoxycortisol and their enrollment in an equation using logistic regression analysis yielded an overall predictive accuracy 96.8% for diagnosis of 11 beta hydroxylase deficiency and 21 deoxycortisol deficiency ER -