4CPS-200 Case report: treatment of digoxin intoxication in a haemodialysis patient using anti-digoxin antibodies and plasmapheresis

<h3>Background and Importance</h3> Digoxin intoxication is a life-threatening condition in which digoxin-specific antibody fragments (Fab) have been shown to be effective¹. In patients with renal failure and chronic haemodialysis (HD), the clearance of Fab-digoxin complexes is significantly reduced. Some cases report using plasmapheresis (PE) to remove complexes and prevent toxicity recurrence^1–8. This case presents the combined use of Fab and PE in a severe digoxin intoxication <h3>Aim and Objectives</h3> Male, 84 years-old, weight 71kg, was admitted to the emergency department for asthenia. His medical record included permanent atrial fibrillation (AF), congestive heart failure, stage V chronic kidney disease on HD and diabetes mellitus. His regular medication includes apixaban, bisoprolol, 0.25mg digoxin, furosemide, sitagliptin, simvastatin, and trazodone. <h3>Material and Methods</h3> Physical examination revealed a blood pressure of 160/92 mmHg, an ECG showing AF with complete atrioventricular block with a heart rate (HR) of 40 bpm and narrow QRS. Positive Sars-Cov2 PCR. Digoxin levels (DL) 5.73 ng/ml. Consequently, he was hospitalised in the intensive care unit (ICU). We used the following formula⁹ to calculate the dose of Fab to administer and figure 1 shows a timeline with the interventions performed and clinical parameters: After the first administration, we observed a rebound effect increasing the DL. Therefore, we decided to perform a PE 3 hours after Fab administration, and the LD were significantly reduced. <h3>Results</h3> The acute process lasted eight days and required four administrations of Fab, the last three followed by a PE session. This combination reduced the LD by 43%, 60% and 47%, respectively. HR was re-established with the decrease DL, reaching stable values on day 9 allowing the patient being discharged from the ICU. <h3>Conclusion and Relevance</h3> The combination of PE after Fab administration is not described in clinical guidelines, only a few published cases^1–8. There is also no consensus on when to perform PE, although it is estimated that the optimal time is 1–3h after Fab administration⁵. In this case, we observed a significant benefit of Fab administration followed by PE on clinical symptoms and DL. Further studies are needed to determine when PE should be used in clinical practice. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest