Introductıon
17-hydroxylase (17-OH) deficiency is a rare form of congenital adrenal hyperplasia resulting from mutation in CYP17 gene (Chung et al., 1987). It is an a autosomal recessive defect and estimated incidence is approximately 1 in 50.000 individuals (Grumbach et al., 2003). This enzyme is necessary to convert pregnenolone to 17-hydroxypregnenolone and progesterone to 17-hydroxyprogesterone. Absence of this enzyme impairs all sex steroid and cortisol production. It cause to reduced or absent levels of both gonadal and adrenal sex hormones result in sexual infantilism. Patients are usually diagnosed during an evaluation of delayed puberty. We reported a female patient with  typical of 17OHD.

Case
A 22-year-old female patient was admitted due to primary amenorrhea and chronic weakness. She had 3 normal siblings and parents of patients were consanguinious. Physical examination revealed sexual infantilism (Figure 1). Persistant hypokalemia (3.1 meq/L) and metabolic alkalosis were determined (pH 7.6). Karyotype of the patient was 46XX. Serum cortisol (0.8 mcg/dL), aldosterone (40 pg/mL), DHEAS (14,8 ug/dL), estradiol (<11,8 pg/dL), total testesteron (<10 ng/dL) and 17-OH progesterone (0,46 ng/mL) levels were low, whereas ACTH (119 pg/mL), FSH (86 mIU/L) and progesterone levels were high (11 ng/mL, normal range <1.5 ng/mL). With these findings we suspected from congenital adrenal hyperplasia and an ACTH stimulation test with 1 mg tetracosactrin was performed. Results pointed out an 17-alpha hydroxylase deficiency (17-OH progesterone levels were low (baseline: 0,46 ng/mL, 30^th min: 0.52 ng/mL, 60^th, min: 0.53 ng/mL, 90^th min: 0.55 ng/mL) and hydrocortisone (10 mg/day) and ethinyl estradiol 0,03 mg/day was started.
 

Figure 1 Apperance of the patient with sexual infantilism

Dıscussion
17OHD is a very rare syndrome and there was only 1 case reported in Turkey (Kandemir and Yordam, 1997).  Prevalence may be more common in Brazil (Belgini et al., 2010). The classical presentation of 17OHD is hypokalemia and delayed puberty (Biglieri et al., 1996). Approximately 90% patients are hypertensive or hypokalemic at presentation. Our patient had all the classical features of this syndrome apart from hypertension. Adrenal insufficiency does not reflect  classical fetaures of Addison's disease because of increased production of corticosterone. Our patient had normal female phenotype, primary amenorrhea with sexual infantilism (absence of breast development and axillary and pubic hair). Deficient estrogen production explains hypergonadotropic hypogonadism. Estrogen therapy is given for induction of puberty and could be required with progesterone in later life to prevent osteoporosis. Parents of our patient were consanguineous and there was no any similar patient of family history of the patient, therefore, consanguineous marriage may be responsible for emerging of this patient.

As a conclusion, although 17OHD is a rare cause of CAH and primary amenorrhea; it should be considered when delayed puberty occurs in patients with hypokalemia and hypergonadortropic hypogonadism.

References
Chung B.C., Picado-Leonard J., Haniu M., Hall P.F., Shively J.E., Miller W.L., 1987, Cytochrome P457c17 cloning of human adrenal and testis cDNAs indicates the same gene is expressed in both tissues, Proc. Natl. Acad. Sci. U S A., 84: 407-411 http://dx.doi.org/10.1073/pnas.84.2.407 PMid: 3025870 PMCid: 304216
 
Grumbach M.M., Hughes I.A., and Conte F.A., 2003, Disorder of sex differentiation, In: Larsen P.R., Kronenberg H.M., Melmed S., eds., Williams textbook of endocrinology, 10th edtion, Philadelphia: Saunders, pp.842-1002
 
Kandemir N., and Yordam N., 1997, Congenital adrenal hyperplasia in Turkey: A review of 273 patients, Acta Paediatr, 86(1): 22-25 http://dx.doi.org/10.1111/j.1651-2227.1997.tb08824.x PMid: 9116420 
 
Belgini D.R., Mello M.P., Baptista M.T., Oliveira D.M., Denardi F.C., Garmes H.M., Grassiotto Oda R., Benetti Pinto C.L., Marques-de-Faria A.P., Maciel-Guerra A.T., and Guerra-Júnior G., 2010, Six new cases confirm the clinical molecular profile of complete combined 17a-hydroxylase/17,20-lyase deficiency in Brazil, Arq. Bras. Endocrinol. Metabol., 54(8): 711-716 http://dx.doi.org/10.1590/S0004-27302010000800008 PMid: 21340157 
 
Biglieri E.G., Herron M.A., and Brust N., 1996, 17-α-Hydroxylase deficiency in man, J. Clin. Invest., 45: 1946-1954 http://dx.doi.org/10.1172/JCI105499 PMid: 4288776 PMCid: 292880