MON-005 AN UNUSUAL CASE OF VASOMOTOR SYMPTOMS IN A POST-MENOPAUSAL WOMAN

Disclosure: R. Akhter: None. W. Akhter: None. A. Zaidi: None. J.L. Gilden: Novartis Pharmaceuticals. Introduction: Hot flashes are among the most common menopausal symptoms affecting up to 74% of women and often impair quality of life. They are a rapid and exaggerated response to heat characterized by sweating, peripheral vasodilation, and intense feeling of heat. The exact pathogenesis is unknown, but studies indicate that vasomotor symptoms result from a central thermoregulatory function defect. Various hormones and neurotransmitters modulate vasomotor symptoms, most importantly estrogen. It is believed that estrogen depletion at menopause triggers small elevations in core body temperature leading to hot flashes. Norepinephrine and serotonin also have a role in defective thermoregulation, which is why SSRIs and SNRIs have been used to treat vasomotor symptoms. A temporal relationship has also been observed between hot flashes and LH pulses. Other studies suggest that there is isolated gonadotropin deficiency but no LH pulses, however cases with hypothalamic amenorrhea had LH pulses but no hot flashes. CASE PRESENTATION We present the case of a 73-year-old woman who presented to the endocrine clinic at the age of 70 for evaluation and management of persistent vasomotor symptoms of 30-40 years duration. Past CT neck showed bilateral neck adenopathy and mediastinal lymphadenopathy. An axillary lymph node biopsy led to a diagnosis of possible Sarcoidosis. The hot flashes occurred 4-5 times a week, more at night, despite the use of portable fans and removal of clothes. Laboratory: TSH 3.986 uIU/mL(Normal 0.550-4.780), Free T4 0.9 ng/dL(Normal 0.89-1.76), Free T3 3.30 pg/mL(Normal 2.30-4.20), Free testosterone 2.9 pg/mL(Normal 0.2-3.7), Total testosterone 17 ng/dL(Normal 2-45), 5HIAA 7.3 mg/24 h (Normal <=6 mg/24 h), plasma metanephrines <25 pg/mL(Normal <=57), plasma normetanephrines 63 pg/mL(Normal <=148), Prolactin 5.60 ng/mL (Normal 1.8-20.3), Estradiol <11.8 pg/mL(normal <11-32.2), low FSH 9.30 mIU/mL(Normal 23-116.3), low LH 2.90 mIU/mL(Normal 5-55.2), IgF-1 105 ng/mL(Normal 34-245 ng/mL), late night salivary cortisol 0.07 and 0.03 mcg/dL(Normal < = 0.09), DHEAS 80.32 ug/dL(Normal 25.9-460.20), Androstenedione 47 ng/dL(Normal 20-75). LH and FH were repeatedly inappropriately low on multiple occasions. FSH 8.20 8.30 mIU/mL, and LH 3.77, 3.04 mIU/mL.CONCLUSION Hot flashes are often associated with menopause. However, other conditions (carcinoid tumors, pheochromocytoma, hyperthyroidism, acromegaly, medullary carcinoma of the thyroid, systemic mastocytosis and idiopathic anaphylaxis) and drugs (clomiphene, tamoxifen, TCAs and Ca channel blockers) can also cause hot flashes. Patients with autonomic dysfunction can also have abnormal temperature regulation. Our case highlights that is it important to recognize suppressed FSH and LH levels in a patient and evaluate broadly for causes of vasomotor symptoms instead of attributing them entirely to menopause. Presentation: Monday, July 14, 2025