Objective: Fomepizole is the antidote of choice in toxic alcohol poisonings. Potential side effects from frequent use of fomepizole were studied in a patient admitted 154 times with ethylene glycol (EG) poisoning. The intra-individual correlation between the serum-ethylene glycol (serum-EG) and the osmolal gap (OG) EG-kinetics, and other laboratory parameters were also studied.
Methods: Combined pro- and retrospective collection of material from three different hospitals, and results from autopsy.
Results: A 26-year-old female with a dissociative disorder was admitted with EG poisoning a total of 154 times. Her admission data revealed a median pH of 7.31 (range 6.87-7.49), pCO(2): 4.2 kPa (1.2-6.7) (32 mmHg [9-50]), HCO-3: 15 mmol/L (4-26) (15 mEq/L [4-26]), base deficit (BD): 10 mmol/L (- 4 to 27) (10 mEq/L [-4 to 27]), serum-creatinine 65 μmol/L (40-133) (0.74 mg/dL [0.45-1.51]), OG 81 mOsm/kgH(2)O (25-132), and serum-EG 44 mmol/L (4-112) (250 mg/dL [25-700]). She was treated with fomepizole 99 times, ethanol 60 times (with a combination of both six times), and dialysis 73 times. The correlation between serum-EG and OG was good (r(2) = 0.76). She was finally found dead outside hospital with an EG blood concentration of 81 mmol/L (506 mg/dL). An autopsy revealed calcium oxalate crystals in the kidneys, slight liver steatosis, and slight edema of the lungs.
Discussion: The frequent use of fomepizole in this young patient was not associated with any detectable side effects; neither on clinical examination and lab screening, nor on the later autopsy. Regarding the sequelae from the repetitive EG-poisoning episodes, her kidney function seemed to normalize after each overdose. She was treated with buffer and antidote without hemodialysis 81 times without complications, supporting the safety of this approach in selected cases.