Rare case of refractory hypokalaemia in a patient with acute myelomonocytic leukaemia (AML M4): a case report

A 39-year-old man, who was recently diagnosed with Acute Myelomonocytic Leukaemia (AML M4 subtype), presented at the Emergency Department of Ayub Teaching Hospital, Abbottabad, with all the common symptoms of AML, including anaemia, bleeding, and generalised weakness. What makes this case report interesting is the presence of severe refractory hypokalaemia. He was admitted to the Medical D unit of Ayub Teaching Hospital, Abbottabad, on January 14, 2024. His serum potassium remained low at 2.4mmol/L, (n=3.5-5.1 mmol/L) despite aggressive potassium replacement. Urinary electrolyte analysis showed renal potassium wasting, likely due to activation of the renin-angiotensin-aldosterone system (RAAS). Elevated serum renin levels supported this mechanism. In addition, the patient also had acute kidney injury and electrolyte abnormalities potentially caused by excessive lysozyme secretion by monocytes, as described in a prior case report. Refractory hypokalaemia in AML M4 is rare and has a poor prognosis. Early recognition and management of hypokalaemia is crucial to prevent complications and improve patient outcomes. This case highlights the importance of monitoring electrolytes and the need for further research on ideal management protocols for refractory hypokalaemia in AML M4. Keywords: Acute Myelomonocytic Leukaemia, Acute kidney injury, Renin-angiotensin-aldosterone system, Severe refractory hypokalaemia, Urinary electrolyte analysis.