Management of haemolysis-induced hyperkalaemia in an extremely low birthweight infant exposed to maternal sulfasalazine.

Sulfasalazine is a non-specific immunomodulator with haemolytic anaemia as a known side effect that crosses the placenta. We present a preterm neonate with cardiac arrhythmia secondary to hyperkalaemia in the setting of maternal sulfasalazine therapy. A preterm infant was born to a mother taking hydroxychloroquine, sulfasalazine, aspirin and enoxaparin throughout pregnancy. Ventricular tachycardia developed at 24 hours of life with a serum potassium of 7.2 mmol/L and hyperkalaemia medication treatment resulted in the resolution of the arrhythmia. At 42 hours of life, arrhythmia reoccurred with a serum potassium of 8.8 mmol/L. Treatment for hyperkalaemia was initiated without a return to normal sinus rhythm, thus rectal sodium polystyrene sulfonate was administered and electrocardiogram (EKG) normalised. This is the first reported case of hyperkalaemia in a neonate associated with maternal sulfasalazine use. Healthcare professionals should be aware of potential electrolyte alterations with sulfasalazine use during pregnancy.