Reproductive Endocrinology MCQs

This girl most probably has Turner's syndrome , which is most commonly associated with absence of one X chromosome (XO pattern). Characteristic features in this condition include streak ovaries and absent internal genitalia. Estrogen administration will develop female secondary sex characters and life-long therapy will be required. Growth hormone may be useful for a limited period to increase her height. As the ovaries are absent, pulsatile GnRH and luteinising hormone would be of no use. Progesterone would be useful for inducing withdrawal bleed in females sufficiently treated with estrogen. Reference : Harrison's Principles of Internal Medicine 21 st edition Page 3000

Kallmann's syndrome is hypogonadotropic hypogonadism with anosmia. It is due to defective hypothalamic gonadotropin-releasing hormone (GnRH)synthesis. KAL gene defect on chromosome Xp22.3 is the culprit. Embryonic migration of GnRH neurons from hypothalamic olfactory placode to hypothalamus is prevented due to this genetic defect. Reference : Harrison's Principles of Internal Medicine 21 st edition Page 3013

Five most important causes for anovulation in females include PCOS and other hyperandrogenic disorders, hypothalamic anovulation, hyperprolactinemia, POI and chronic illnesses Reference : Williams Textbook of Endocrinology 14th edition Page 601

This is polycystic ovarian syndrome (PCOS). Oligo/amenorrhoea is present in 70%, hirsutism in 60%, obesity in 35% and infertility in 30%. LH is usually markedly raised, as is the LH/FSH ratio. Sex hormone-binding globulin is low in 50% of sufferers primarily due to hyperinsulinaemia. Testosterone and DHEAS (dehydroepiandrosterone) levels are also usually raised. Up to 40% of women with PCOS may have impaired glucose tolerance, and up to 10% frank type-2 diabetes mellitus. The insulin-resistant state is also associated with dyslipidemia. Management is usually with weight loss and lifestyle advice. Metformin is a useful treatment for insulin resistance and may help restore fertility, although clomiphene may also be required for ovulation induction. Reference : Harrison's Principles of Internal Medicine 21 st edition Page 3035

Hypertension is quite common in Turner syndrome (10%) and is typically idiopathic i.e. essential hypertension. In a small proportion of cases, causes can include coarctation of the aorta and renal dysfunction due to horse-shoe kidney. In this case, the absence of specific features of coarctation would make essential hypertension the most appropriate option. Reference: Harrison's Principles of Internal Principles, 20 th edition, ch:271 pg:1896

Menarche may be delayed in girls who are involved in strenuous physical activity. This is termed as"Functional hypothalamic amenorrhea" in which strenuous physical activity, caloric restriction and extreme stress can lead to reduced GnRH and gonadotropins production from hypothalamus and pituitary. Treatment with GnRH or gonadotropins are not required as the reversal of these risk factors would lead to resumption of normal menstrual cycles. Provision of an adequate diet and the relief of stress would be the most appropriate treatment in this case. Reference: Harrison's Principles of Internal Medicine 21 st edition Page 3035

VIPomas in adults are usually neuroendocrine islet cell tumors of the pancreas that produce high amounts of VIP. Other secreted hormones may include secreted gastrin and pancreatic polypeptide. Achlorhydria (lack of acidity from the stomach) is classically associated with VIPoma. It can be diagnosed by measuring acid output from nasogastric contents (NG tube). Features of VIP syndrome include watery diarrhea, hypochlorhydria, hyperglycemia, hypercalcemia and flushing. Hypoglycemia is associated with insulinoma Pellagra a condition caused by niacin deficiency occurs in carcinoid syndrome Migratory erythema associated with glucagonoma. Reference: Harrison's Principles of Internal Medicine, 21 st Ed, Ch: 84 Pg: 665

Gastrin is produced by the G cells of gastric antrum . It stimulates parietal cells to produce hydrochloric acid. Its production is stimulated by neural reflex pathways and also by direct effect of digested peptides on the G cells. Normal fasting gastrin levels are usually 150-200mg/dL Reference : Harrison's Principles of Internal Medicine, 21 st ed, Ch: 324, Pg: 2453