Prevalence and Characteristics of Adrenal Tumors and Myelolipomas in Congenital Adrenal Hyperplasia: A Systematic Review and Meta-Analysis

Abstract

Objective: The prevalence of adrenal tumors in congenital adrenal hyperplasia (CAH) is uncertain. Our objective was to estimate the prevalence and characteristics of adrenal tumors and myelolipoma in CAH, and investigate clinical features of this population.Methods: We carried out systematic searches in Medline Ovid and Embase for articles published until January, 2020. Studies with confirmed CAH, biochemically and/or genetically, were included. The two authors independently extracted data from each study.Results: Six cohort studies were included in the prevalence calculation. In addition, 32 case reports on adrenal myelolipomas and CAH were included. The prevalence of adrenal tumors in CAH was 29.3%. When only studies with genetically verified cytochrome P450, Family 21, subfamily A, polypeptide 2 gene (CYP21A2) mutations were included the prevalence was 23.6%. The prevalence of myelolipoma in CAH was 7.4% (verified CYP21A2 mutations 8.6%). The proportion of myelolipoma in the adrenal tumors was 25.4% (genetically verified 36.6%). The median (range) age at tumor diagnosis was 36.0 (12 to 60) years and there were more tumors in males than in females (37.9% versus 22.1%; P<.05). In patients with myelolipomas, 93.5% had an undiagnosed or poorly managed CAH.Conclusion: Patients with CAH had a high prevalence of adrenal tumors, particularly myelolipomas. Those with myelolipomas had a high frequency of late-diagnosed or poorly controlled CAH. Adrenal imaging may be considered in patients with CAH, especially if abdominal pain is present.