Pseudohypoparathyroidism presenting with ventricular arrhythmia: a case report.

Area of Science:

• Endocrinology
• Cardiology

Background:

• Pseudohypoparathyroidism (PHP) is a rare genetic disorder characterized by parathyroid hormone resistance.
• Clinical manifestations typically include hypocalcemia, hyperphosphatemia, and Albright's hereditary osteodystrophy features.
• Cardiac complications, specifically arrhythmia, have not been previously described in association with PHP.

Observation:

• A male adolescent diagnosed with PHP type 1a presented with ventricular extrasystoles (bigeminy, trigeminy) and QT interval prolongation.
• Physical examination revealed brachydactyly, with longer second fingers and toes.
• Laboratory findings included hypocalcemia, hypomagnesemia, elevated creatine kinase, and lactate dehydrogenase.

Findings:

• The patient's hypocalcemia-induced ventricular arrhythmia and laboratory abnormalities improved with calcium and vitamin D supplementation.
• This case represents the first documented instance of cardiac arrhythmia as a manifestation of hypocalcemia in pseudohypoparathyroidism.
• Hypomagnesemia was identified as a potential contributing factor, increasing susceptibility to hypocalcemia and subsequent cardiac events.

Implications:

• This case suggests that cardiac arrhythmia should be considered in the differential diagnosis of hypocalcemia in PHP patients.
• Hypomagnesemia may exacerbate hypocalcemia and predispose PHP patients to cardiac complications.
• Further research is warranted to elucidate the relationship between PHP, hypomagnesemia, and cardiac electrophysiology.