Objectives: To summarize the characteristics, differential diagnosis and management of incomplete 17 alpha-hydroxylase/17, 20-lyase deficiency (17 OHD) of Chinese patients.
Methods: Six cases of incomplete 17 OHD from Peking Union Medical College Hospital were studied retrospectively through analyzing their clinical data, and the molecular pathogenic mechanism was discussed after literature review.
Results: Four cases of 46, XX incomplete 17 OHD were reported. The clinical characteristics included female phenotype, various degrees of breast development and absent or sparse axillary/pubic hair, oligomenorrhea or secondary amenorrhea, recurrent luteinized ovarian cysts, hypogonadism with persistent hyperprogesteronemia or high serum 17 alpha-hydroxyprogesterone level, with or without hypokalemic hypertension. There were also 2 cases of 46, XY incomplete 17 OHD, in which ambiguous genitalia were present besides hypokalemic hypertension.
Conclusions: Incomplete 17 OHD is a very rare form of congenital enzymatic deficiencies of steroid synthesis, which should be included in the differential diagnosis when there are menstrual disorders, sexual infantilism, recurrent ovarian cysts or ambiguous genitalia. Under such circumstances, hyperprogesteronemia offers a valuable clue for further investigation.