We conclude that higher serum sclerostin levels are associated with a greater risk of hip fractures in older women. In addition, the risk of hip fracture is amplified when high sclerostin levels are combined with lower BMD.

Sclerostin is a potent inhibitor of bone formation but has been shown to correlate positively with areal bone mineral density (aBMD). Little is known about its relationship to parameters of bone strength and volumentric BMD (vBMD) as measured by peripheral quantitative computed tomography (pQCT). We measured both serum sclerostin and parameters of tibial bone size and strength by pQCT to characterize this relationship. Our study population consisted of 223 Caucasian and 35 African American women (mean age 87) from the Study of Osteoporotic Fractures (SOF) cohort, who had usable pQCT scans of the tibia at sites 4% (T4%), 33% (T33%), and 66% (T66%) from the ankle. Analysis of covariance was used to test for differences in age-adjusted means of aBMD, pQCT variables, and serum biomarkers across sclerostin quartiles. Black women had significantly lower median sclerostin (34.3 pmol/L) than white women (48.5 pmol/L) (p=0.05). Women in the highest sclerostin quartile had 7-14.5% higher hip aBMD and pQCT parameters of vBMD and bone size than those in the lowest quartile in multivariate models adjusting for age, race, weight, height and diabetes. The association of sclerostin with parameters of bone strength differed dramatically between T33% and T66% sites. At T66%, women in the highest sclerostin quartile had pQCT strength parameters 9.4-15.3% greater than the lowest quartile, whereas no trend was found for the T33% site. Our results suggest paradoxical associations between circulating sclerostin and bone size, density and strength.

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Lithium (Li) carbonate has been established as a mood stabilizer and an efficacious treatment for bipolar disorder since its discovery by Dr. John Cade in 1948. Li interacts significantly with organ systems and endocrine pathways. One of the most challenging side effects of Li to manage is its effect on the parathyroid glands. Dysregulation of parathyroid signaling due to Li results in hypercalcemia due to increased vitamin D3 generation, increased calcium absorption from the gut, and bone resorption, occasionally resulting in concomitant hypercalciuria. However, hypercalciuria is not a definitive feature for hyperparathyroidism, and normal calcium excretion might be seen in these patients. Hypercalcemia may also result from volume contraction and decreased renal clearance, which are commonly seen in these patients. Anatomically the parathyroid abnormalities can present as single or multiglandular disease. We report 3 cases where the patients developed multiple side effects of Li therapy as well as hypercalcemia due to hyperparathyroidism. The literature is reviewed with regard to medical and surgical management of Li-associated hyperparathyroidism in the context of these 3 presented cases.

Background Myelolipomas are rare, benign tumors of the adrenal gland that consist of adipose and hematopoietic tissue. Most present unilaterally and rarely exceed 4 cm, but bilateral and large myelolipomas have been reported. The development of these neoplasms has been associated with congenital adrenal hyperplasia (CAH) (1). Clinical Case A 44-year-old woman with a history of simple virilizing CAH follows in endocrine clinic. She was diagnosed with CAH at birth and underwent vaginoplasty procedures at age 8 and 16. She has been on glucocorticoid therapy with hydrocortisone or prednisone throughout her life, but has had long gaps in treatment (sometimes up to a year) and reports often skipping doses due to concerns regarding facial swelling. She has not had a menstrual cycle for many years and reports shaving her facial hair daily. Her ACTH has been as elevated as 830 pg/mL, 17-alpha-OH-P has been as elevated as 17740 ng/dL, and testosterone as elevated as 401 ng/dL. She now presents for evaluation of an umbilical hernia. She did not have any abdominal or flank discomfort. CT abdomen and pelvis with contrast was obtained and showed bilateral, massive (approximately 25 cm and 18 cm in the largest dimensions on each side) suprarenal masses thought to most likely represent adrenal myelolipomas. She was referred to endocrine surgery and is undergoing discussions regarding possible adrenalectomy. Since the discovery of these adrenal masses, she has been consistently taking prednisone 5 mg daily. Conclusion This case illustrates the potential role of poorly-controlled CAH in the development of massive adrenal myelolipomas. Many hypothesize chronic ACTH stimulation can cause metaplasia of adrenocortical cells and lead to the development of myelolipomas. Review of the medical literature reveals no clear consensus on the management of these rare neoplasms (2). References (1) Al-Bahri S, Tariq A, Lowentritt B, Nasrallah DV. Giant bilateral adrenal myelolipoma with congenital adrenal hyperplasia. Case Rep Surg. 2014;2014: 728198. doi: 10.1155/2014/728198. Epub 2014 Jul 16. PMID: 25140269; PMCID: PMC4124659. (2) German-Mena E, Zibari GB, Levine SN. Adrenal myelolipomas in patients with congenital adrenal hyperplasia: review of the literature and a case report. Endocr Pract. 2011 May-Jun;17(3): 441-7. doi: 10.4158/EP10340.RA. PMID: 21324823. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.