Doshi, Krupa

Purpose of review Normocalcemic primary hyperparathyroidism (NPHPT) is defined by persistently elevated parathyroid hormone (PTH) levels in the presence of normal total and ionized serum calcium after excluding secondary causes of PTH elevation. Increasing use of biochemical screening has led to growing recognition of this phenotype, yet uncertainties remain regarding its natural history, diagnostic criteria, and optimal management. Recent findings NPHPT shares several clinical features with hypercalcemic primary hyperparathyroidism (HPHPT). Substantial rates of osteoporosis, fragility fractures, and nephrolithiasis are reported. Diagnosis requires repeated biochemical measurements, confirmation of normal ionized calcium, and rigorous exclusion of secondary causes such as vitamin D insufficiency, chronic kidney disease, malabsorption, and medication effects. Preoperative localization may also be more difficult than in HPHPT due to smaller adenomas and higher prevalence of multigland disease. Summary Parathyroidectomy appears safe and effective in selected individuals. However, NPHPT may carry a greater risk of recurrence than HPHPT. Improvements in bone mineral density (BMD) and quality of life (QOL) have been reported after surgery, although renal outcomes remain less certain. This review summarizes current evidence on the epidemiology, diagnosis, clinical manifestations, and management of NPHPT and highlights key areas requiring further study.

Abstract Disclosure: J. Arguinchona: None. N. Allen: None. M. Vahidi Rad: None. K. Doshi: None. Background: Thyrotoxic periodic paralysis (TPP) is a distinct disorder characterized by episodic, generalized muscle weakness due to hypokalemia, occurring predominantly in young adult males (20-40 years) with hyperthyroidism, particularly Graves' disease. TPP is common in East Asian populations, affecting approximately 2% of individuals with hyperthyroidism, but is rare in Western populations (0.1-0.2%) and often underrecognized in the United States. Herein, we present three cases of TPP in young Hispanic and Caucasian males with Graves’ disease, underscoring the importance of diagnostic vigilance. Clinical Cases: Case 1: A 21 y.o. Hispanic male presented to endocrine clinic following multiple hospitalizations for severe hypokalemia and myopathy. During admission, labs showed a potassium (K) 1.2 mmol/L (3.6-5.2), undetectable thyroid stimulating hormone (TSH), and free thyroxine (FT4) 2.8 ng/dL (0.9-1.7). K was replaced and Graves’s disease was confirmed by positive TSH receptor antibodies. He was started on methimazole and subsequently underwent radioactive iodine (I-131) therapy. Following development of hypothyroidism, he was placed on levothyroxine replacement, with no further recurrence of paralysis. Case 2: An 18 y.o. Caucasian male with a history of Graves’ disease presented after multiple hospitalizations for hypokalemia and lower extremity weakness. Hospitalization labs showed a suppressed TSH, FT4 2.2 ng/dL, free triiodothyronine (FT3) 7.9 pg/mL (2.3-4.1), and K 2.8 mmol/L. His weakness improved with K replacement. Methimazole was initiated and the patient subsequently opted for total thyroidectomy for definitive therapy. No recurrence of TPP was observed after thyroidectomy. Case 3: A 29 y.o. Hispanic male with Graves’ disease, non-adherent to methimazole was hospitalized due to symptoms of diffuse upper and lower extremity weakness. Labs showed K 1.6 mmol/L, undetectable TSH, and T4 >7.7 ng/dL. Symptoms resolved with K replacement. He was restarted on methimazole as well as atenolol and advised on medical adherence. Unfortunately, he was lost to follow up, and re-hospitalized 7 months later with similar symptoms and labs, again due to nonadherence with thionamide medication. After aggressive K replacement and methimazole resumption, he was discharged with urgent endocrine follow-up for definitive management of Graves’ disease. Conclusion: These cases highlight the under recognition of TPP in non-Asian populations in the United States, leading to delayed diagnosis and recurrent hospitalizations. Clinicians should maintain a high index of suspicion for TPP in young males with hypokalemia, and generalized weakness, particularly in the setting of undiagnosed or untreated hyperthyroidism. Prompt recognition and definitive treatment of hyperthyroidism is critical to preventing recurrent episodes and associated morbidity. Presentation: Saturday, July 12, 2025

Abstract While adrenal androgen production is primarily regulated by ACTH, some data suggest a less common association between hyperprolactinemia and elevated dehydroepiandrosterone sulfate (DHEA-S). We describe 2 patients with this underrecognized connection. Patient 1, a 60-year-old male, was incidentally found to have bilateral adrenal masses on computed tomography during evaluation of gastrointestinal complaints. Further workup revealed elevated levels of DHEA-S and prolactin, with pituitary macroadenoma identified as the cause, given normalization of both prolactin and DHEA-S on cabergoline therapy. Patient 2, a 38-year-old male, presented with visual field defects, and subsequent pituitary magnetic resonance imaging confirmed a macroadenoma. He also had markedly elevated levels of DHEA-S and prolactin. Both patients were treated with cabergoline, leading to rapid normalization of both prolactin and DHEA-S levels. These cases demonstrate an association between hyperprolactinemia and elevated DHEA-S, supported by the normalization of levels with medical treatment of prolactinoma. Although hyperprolactinemia in the context of a prolactinoma is an uncommon cause of elevated DHEA-S, it should be considered once other etiologies have been excluded.

Abstract Lifestyle at the habitation immensely affects the progression of various illnesses, such as Osteoporosis and Parkinson’s disease (PD). These disorders lead patients to a sedentary lifestyle and result in significantly less movement compared to the average healthy individual. The combination of these backgrounds escalates the percentage of fall incidents. Quantifying physical activity levels from longitudinal Activities of Daily Living (ADL) data of these disease patients could stipulate intuition of their fall mechanisms. The objective of this study is to compare the osteoporosis, Parkinson's disease, and healthy group’s physical activity level from their ADL. For this study total of eighteen subjects participated (healthy=6, osteoporosis=6, PD=6). The result indicated that the dynamic physical activity level for the healthy subject was 13.2%, the osteoporosis subject was 7.9%, and the PD subject was 7.0%. This indicates that there was a significant decline in physical activity level for the PD compared to healthy subjects (P=0.0024*). Also, a comparison between healthy and osteoporosis subjects showed a significant difference (P=0.0066*). Lastly, the physical activity level of PD and osteoporosis subjects did not have a significant difference among them (P=0.6276). The aim of this study was to evaluate the physical activity level of the osteoporosis, PD, and healthy subjects. The systematic approach of collecting physical activity levels with the Inertial Measurement Unit (IMU) device allowed researchers to collect the quantitative data of ADL. In this experiment, healthy subjects were significantly more physically active compared to osteoporosis and PD patients.

AbstractA 36‐year‐old man was treated for several years with multiple agents for ankylosing spondylitis based on positive human leukocyte antigen‐B27 and sacroiliitis. He was also diagnosed with osteoporosis and hypophosphatemia. Over these years, from being an avid runner, he became dependent on a walker for ambulation. The lack of treatment response and the low phosphorus were clues that eventually led to a diagnosis of tumor‐induced osteomalacia. This case discusses the importance of not solely relying on genetic markers and sacroiliitis for diagnosing ankylosing spondylitis as other conditions can cause similar presentations.