Endocrine Abstracts

Background: X and Y chromosomes carry many genes that direct development and gametogenesis. Rearrangements associated with X chromosome may have a role in abnormal phenotypes. We presented a case of primary amenorrhea with normal karyotype but centromere thickness in 13th chromosome (13 cenh⁺), this is the first case in literature.

Case: A 18-year-old woman admitted to endocrinology clinic with complaints of primary amenorrhea and a failure in breast development. Her medical history was insignificant. In physical examination her height, weight and BMI were 1.61 m, 48.5 kg and 20 kg/m² respectively. Axillary and pubic hair were Tanner stages 2–3, breast was stage 2. The patient had not facial dysmorphism, webbed neck and skeletal abnormalities. Complete blood count and biochemical values were normal. Hormonal evaluation revealed hypergonadotropic hypogonadism (LH: 28.8 mU/ml, FSH: 57 mU/ml, estradiol: 10 pg/ml) and normal prolactin and thyroid function tests. Karyotype analysis was performed with GTG (Giemsa-Trypsin) banding technique and 46, XX, 13 cent⁺ chromosome abnormality was detected. Band thickness in centromere region and increase in centromere heterochromatine length of chromosome 13 were detected. Pelvic MR revealed no ovaries and normal uterus. Hypophysis MR was normal. For breast development estrogen treatment was started and then changed to combined estrogen and progesterone treatment. After treatment patient’s menstrual cycles were started and patient is under follow up for 3 years.

Discussion: Premature ovarian failure (POF) may present with primary or secondary amenorrhea. POF has many causes include increased atresia due to chromosomal abnormalities, autoimmune diseases, infections, radiation and chemotherapy. A terminal rearrangement in chromosomes 13 and 20 was presented in a patient with primary amenorrhea. In our case 46, XX, 13cenh⁺ was detected. This abnormality was not presented in literature previously. But we know various dislocations and deletions in X chromosome may cause gonadal disgenesis in light of previous literature. Therefore we speculate that an association may be present between centromere thickness in 13th chromosome and gonadal disgenesis in our case.