A 72-year-old woman with bipolar disorder and hypertension presents to her primary care physician for evaluation of fatigue and new-onset flank pain. She has been on lithium carbonate for 15 years and hydrochlorothiazide for 8 years. Vital signs are within normal limits. Laboratory studies show: serum calcium 11.8 mg/dL (normal 8.5-10.2), serum phosphate 3.2 mg/dL (normal 2.5-4.5), ionized calcium elevated, PTH 82 mIU/L (normal 10-65), albumin 4.2 g/dL, and 24-hour urine calcium 480 mg (normal <250 mg). Imaging reveals a 7-mm radiopaque stone in the right renal pelvis. Which of the following best explains her current clinical presentation?

1. A)Lithium-induced nephrogenic diabetes insipidus leading to urine concentration and calcium stone formation
2. B)Hydrochlorothiazide-induced hyperparathyroidism with autonomous adenoma formation
3. C)Lithium-induced shift in the parathyroid calcium-sensing receptor set point, causing PTH suppression at higher serum calcium levelsGABARITO
4. D)Hydrochlorothiazide-induced hypercalcemia through enhanced intestinal calcium absorption and decreased urinary calcium excretion
5. E)Chronic lithium use causing tertiary hyperparathyroidism with persistent PTH elevation despite calcium normalization