Atrial fibrillation as the initial presentation of non-Hodgkin lymphoma-induced hypercalcemia

Background Hypercalcemia caused by non-Hodgkin B-cell lymphomas is not common, and it rarely manifests as the first presentation for medical attention. Few case reports describe atrial fibrillation as the presentation of parathyroid hormone-dependent hypercalcemia. However, the medical literature has not previously reported a non-Hodgkin lymphoma patient presenting with atrial fibrillation due to severe hypercalcemia. Case presentation We present the case of a 50-year-old, previously healthy Sri Lankan woman who experienced palpitations for a single day. Upon examination, we discovered supraclavicular lymphadenopathy along with epigastric tenderness and fullness. We found her to have stable, fast atrial fibrillation, and further evaluation revealed severe parathyroid hormone-independent hypercalcemia. A supraclavicular lymph node biopsy revealed a diagnosis of high-grade diffuse large B-cell lymphoma. Atrial fibrillation was converted to a complete heart block after the administration of digoxin in this patient on presentation to the emergency unit, which was corrected after hypercalcemia correction. Conclusion Hypercalcemia can rarely have cardiac involvement, including conduction defects. It is important to assess the calcium level in a patient with cardiac arrhythmias because hypercalcemia is treatable.In a patient with hypercalcemia, it is advisable to avoid digoxin for rate control.