SHM Converge Scientific Abstract ePoster Gallery-The Enigmatic Case of Hypercalcemia

Pdf Summary

This case describes an 80-year-old woman with chronic hypercalcemia who presented with severe calcium elevation (15 mg/dL) and suppressed PTH, suggesting a non-parathyroid cause. Initial evaluation for common etiologies, including malignancy, multiple myeloma, granulomatous disease, and infection, was largely unrevealing. She had a major unintentional weight loss history, elevated beta-2 microglobulin, chronic left leg lymphedema/cellulitis, and a non-healing ulcer, raising concern for an occult cancer or inflammatory process.<br /><br />Further workup showed normal PTHrP but elevated 1,25-dihydroxyvitamin D (calcitriol), pointing toward calcitriol-mediated hypercalcemia. Imaging of the left leg revealed findings suspicious for cellulitis, osteomyelitis, and a possible infiltrative process, including multiple enhancing subcutaneous and intramuscular nodules. Biopsy of a dominant nodule ultimately revealed CD-positive B-cell lymphoma of germinal center origin.<br /><br />The authors conclude that the patient’s hypercalcemia was most likely caused by lymphoma-associated overproduction of calcitriol via tumor expression of 1α-hydroxylase, rather than by the more common PTHrP-mediated mechanism. The report highlights that when PTHrP is normal and PTH is suppressed, clinicians should consider alternative mechanisms of malignancy-related hypercalcemia, including calcitriol production and, less commonly, osteolytic bone involvement.

Asset Subtitle

Tochi Ogbuagu

Meta Tag

Author List Dwayne Wiltshire, Jennifer Beard, Tochi Ogbuagu

Category Clinical Vignettes

Concept Hypercalcemia

Concept Hypercalcemia of Malignancy

Concept Malignancy

Concept Calcitriol

Concept Parathyroid Hormone-related Protein

Distinguished Non-Finalist

Presenter Organization Canton Medical Education Foundation/Neomed

Presenting Author Tochi Ogbuagu

Track Adult

Keywords

hypercalcemia

calcitriol-mediated

B-cell lymphoma

suppressed PTH

PTHrP normal

1,25-dihydroxyvitamin D

lymphoma-associated hypercalcemia

1alpha-hydroxylase

germinal center origin

occult malignancy

Hypercalcemia

Hypercalcemia of Malignancy

Malignancy

Calcitriol

Parathyroid Hormone-related Protein