FRI398 A Case Of Secondary Amenorrhea: Is It Only PCOS To Blame?

Disclosure: P. Panjawatanan: None. S. Riahi: None. S.S. Chaidarun: None. Background: One of the most common causes of secondary amenorrhea is PCOS (polycystic ovary syndrome) which accounts for 30% of the cases. Though not as common, hyperprolactinemia similarly contributes to the condition. Here we describe a patient who presented with secondary amenorrhea from medication-induced hyperprolactinemia with underlying PCOS. Clinical Case: A 31-year-old female with a past medical history of bipolar disorder, hypothyroidism, and PCOS, presented with secondary amenorrhea. The patient started menarche at 11 years old and was diagnosed with PCOS a year later due to irregular menses and hirsutism. The estrogen-containing pill was prescribed, but she developed a blood clot due to Factor V Leiden thrombophilia. She was taking atomoxetine, lithium, mirtazapine, and olanzapine for her psychiatric issues and recently started on paliperidone last year. She reported no period in the past two years after stopping oral contraception. Pregnancy was ruled out. She tried progesterone challenge test but did not have any flow. Transvaginal ultrasound showed thin endometrium. She had IUD placed for contraception. Laboratory testing four months and one year after starting paliperidone showed prolactin of 79.2 ng/mL and 110 ng/mL consecutively. The patient reported headaches but denied galactorrhea or visual loss. There are no signs or symptoms of Cushing’s disease, acromegaly, or hypothyroidism. Further workup showed TSH 1.52 mcIU/mL, estradiol 16 pg/mL, FSH 5.6 mIU/mL, 17-OH progesterone <40 ng/dL, total testosterone 14 ng/dL, ACTH 11 pg/mL, IGF-1 z-score -0.67 SD. MRI brain was ordered, which ruled out pituitary adenoma. Repeat prolactin level remained elevated at 87.7 ng/mL without treatment. We concluded that the patient has secondary amenorrhea from PCOS and antipsychotic-induced hyperprolactinemia. Patient was referred to a psychiatrist for antipsychotic medication changes. Conclusion: Antipsychotics, typically first-generation, are known to cause hyperprolactinemia due to their dopamine-antagonist effect. Prolactin level ranging from 25-100 ng/mL is seen in medication-induced hyperprolactinemia, while particular medication like risperidone and phenothiazines can raise the level to more than 200 ng/mL. Newer agent paliperidone has been reported to induce hyperprolactinemia similarly to risperidone which explains significant prolactin elevation in this patient. Hyperprolactinemia poses a risk for hypogonadism due to suppressed pituitary-gonadal axis, resulting in anovulation and bone loss. Estrogen therapy is considered an adjunct to help with hypogonadism. However, it is contraindicated in patients with thrombophilia. The guideline recommends switching to a low-risk antipsychotic agent if feasible. Despite having an established diagnosis of PCOS, it is important to consider other secondary causes of amenorrhea which may occur concomitantly. Presentation: Friday, June 16, 2023