LAUSR

A 79-year-old man was admitted because of dyspnoea. He had been diagnosed with stage 5 chronic kidney disease and had been receiving monthly continuous erythropoietin receptor activator (CERA) subcutaneously. The chest radiograph showed cardiomegaly and congestion. Extracorporeal ultrafiltration method (ECUM) was conducted for the severe congestion refractory to intravenous diuretics. Since impaired renal function and anuria continued, haemodialysis (HD) was initiated. During the first session of HD, hypotension and headache occurred, suspicious of disequilibrium syndrome. The second session of HD was performed under the condition of dialysate: bicarbonate dialysate containing 8 mEq/L acetate, dialysate flow rate: 500 mL/ min, dialyzer: cellulose triacetate membrane and with intravenous CERA. He complained of headache after the session, subsequently went into cardiac arrest. Cardiopulmonary resuscitation resulted in the recovery. As the setting of dialysis was not changed except for switching ECUM to HD, dialysate was considered as the cause of the deterioration. After changing dialysate to acetate-free dialysate and the dialyzer to a polysulfone, HD could be performed without any complication. Serum acetate level at the second session of HD was 5.2 mmol/L and drug-induced lymphocyte stimulation test was positive for bicarbonate dialysate. At the seventh session of HD, shortly after the injection of CERA, acute deterioration occurred again. Because of the anaphylactic shock due to CERA, ESA was changed to oral hypoxia-inducible factor prolyl hydroxylase inhibitor. He was discharged from the hospital without any complications. Patients on HD usually receive multiple medications such as anticoagulants and ESA, and exposed to dialysate and dialyzer during the session. This makes it difficult to identify the cause of allergies. Our patient was diagnosed with anaphylaxis based on the criteria comprising of respiratory symptoms and hypotension immediately after the injection of CERA. There was only one such case after the intravenous CERA, which was changed from epoetin alfa. In our case, despite the patient had previously received subcutaneous CERA without any complication, intravenous injection resulted in anaphylaxis. Our patient was also allergic to bicarbonate dialysate and showed acetate intolerance (AI). Vasodilatory and cardio depressant effect of acetic acid causes clinical symptoms such as headache, vomiting and hypotension. The serum acetic acid over 2 mmol/L was reported to cause such symptoms in patients with AI. In summary, we described a case of anaphylaxis due to intravenous ESA in HD patient who also had AI. This case highlighted the need for careful attention when changing the administration route of ESA.