Hypophosphatemic Rhabdomyolysis with Moderate Diabetic Ketoacidosis in a COVID-19 Patient Needing Continous Renal Replacement Therapy

Abstract

Introduction: Phosphate is a critical anion in maintaining cellular functions. Notably, most important use of phosphate is for ATP production. Thus, a reduction of phosphate levels is detrimental to every organ system. In this case, we describe a patient who presented with rhabdomyolysis caused by hypophosphatemia, which was worsened due to his DKA. Case: A 67 year old male with past medical history of hypertension, type 2 diabetes mellitus, gout, and prostate cancer diagnosed 1 year before presentation presented to the emergency department for complaints of 1 week of weakness, acutely manifested by the patient falling and being found unresponsive on the bathroom floor. He never lost a pulse and was transferred to a facility where he was found to have COVID-19 and labs concerning for diabetic ketoacidosis. He was then intubated for airway protection and transferred to a higher level of care facility. Upon admission into hospital, patient was found to be in septic shock with hypotension, febrile at 38.9°C and leukocytosis up to 15,000, and was started on broad spectrum antibiotics, an insulin drip, and fluid resuscitation. What was notable was his phosphorous level was below 1mg/dL, and rhabdomyolysis manifested with a CK level of around 40,000, and acute renal failure with oliguria and a creatinine of 5.45mg/dl. He also had a pH of 7.27, and a bicarb of 12. He was eventually started on CRRT due to need for dialysis while being hypotensive on pressors. He was kept in the ICU for 9 days where he was treated for multiple organ system failures including shock liver, NSTEMI, multiple ischemic strokes, and kidney failure. Eventually, the patient's family decided to pursue comfort care and stop all lifesaving measures on day 9 and the patient passed away that evening. Discussion: We discuss a rare case in which a patient with DM2 developed DKA, and as a result developed hypophosphatemia, thus causing rhabdomyolysis that required CRRT in a COVID-19 positive patient. Hypophosphatemic rhabdomyolysis induced by DKA is a rare complication not often seen, which makes the management difficult. Hypophosphatemia is usually managed with oral and IV replacement therapy. However, when treating the DKA, the insulin administered also causes the phosphate to move intracellular, thus further reducing serum concentration of phosphate. Our case highlights the difficulty with dealing with a rare complication of hypophosphatemia such as rhabdomyolysis and efforts used to manage such a patient.