Ethylene glycol toxicity: The role of serum glycolic acid in hemodialysis

Citation
Wh. Porter et al., Ethylene glycol toxicity: The role of serum glycolic acid in hemodialysis, J TOX-CLIN, 39(6), 2001, pp. 607-615
Citations number
17
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Pharmacology,"Pharmacology & Toxicology
Journal title
JOURNAL OF TOXICOLOGY-CLINICAL TOXICOLOGY
ISSN journal
0731-3810 → ACNP
Volume
39
Issue
6
Year of publication
2001
Pages
607 - 615
Database
ISI
SICI code
0731-3810(2001)39:6<607:EGTTRO>2.0.ZU;2-W
Abstract
Objective: To correlate serum glycolic acid levels with clinical severity a nd outcome in ethylene glycol poisoning and to determine if glycolic acid l evels are predictive of renal failure and the need for hemodialysis. Method s: We measured serum ethylene glycol and glycolic acid levels by gas chroma tography/mass spectrometry for 41 admissions (39 patients) for ethylene gly col ingestion and performed retrospective chart reviews. Results: Eight pat ients died, all of whom developed acute renal failure. Of the survivors, 15 also developed acute renal failure, whereas 18 did not, Of those with norm al renal function, 8 had glycolic acid levels below detection limits (<0.13 mmol/L) despite ethylene glycol levels as high as 710 mg/dL; 7 of these pa tients coingested ethanol. Pertinent initial laboratory data for each group are as follows (mean; range): Deceased: pH 6.99 (6.82-7.22); bicarbonate, 4.8 mmol/L (2-9); anion gap, 28.6 mmol/L (24-40); glycolic acid, 23.5 mmol/ L (13.8-38.0); ethylene glycol, 136.5 mg/dL (6-272). Survived/acute renal f ailure: pH 7.07 (6.75-7.32); bicarbonate, 5.6 mmol/L (1-12); anion gap, 28. 7 mmol/L (18-41); glycolic acid, 20.2 mmol/L (10.0-30.0); ethylene glycol, 238.8 mg/dL (12-810). No acute renal failure with glycolic acid >1.0 mmol/L : pH 7.29 (7.12-7.46); bicarbonate, 14.7 mmol/L (4-23); anion gap, 16.5 mmo l/L (10-26); glycolic acid, 6.8 mmol/L, (2.6-17.0); ethylene glycol, 269.1 mg/dL (6-675). No acute renal failure with glycolic acid <1.0 mmol/L: pH 7. 41 (7.38-7.47); bicarbonate, 23.4 mmol/L (17-25); anion gap, 11.8 mmol/L (8 -18); glycolic acid, 0.1 mmol/L (0-0.66); ethylene glycol, 211 mg/dL (8-710 ). The mean time postingestion to admission generally correlated with sever ity as follows: deceased, <greater than or equal to>10.4 h; survived/acute renal failure, greater than or equal to9.9 h; no acute renal failure with g lycolic acid >1.0 mmol/L greater than or equal to6.2 h; no acute renal,fail ure with glycolic acid <1.0 mmol/L. <greater than or equal to>3.7 h. Hematu ria was more prevalent than oxaluria (86% and 41%, respectively), but neith er was individually predictive of acute renal failure. Good correlations we re found between glycolic acid levels and anion gap (r(2) = 0.7724), pH (r( 2) = 0.7921), and bicarbonate (r(2) = 0.6579); poor correlations (r(2) <0.0 023) occurred between ethylene gl,col levels and glycolic acid, PH, anion g ap, and bicarbonate. Measured ethylene glycol values were highly correlated with ethylene glycol values calculated front the osmolal gap (r(2) = 0.933 9), but the latter overestimates the trite value by about 7%, on average. A n initial glycolic acid level <greater than or equal to>10 mmol/L predicts acute renal failure with a sensitivity, of 100%, a specificity of 94.4%, an d an efficiency of 97.6%. Ethylene glycol levels are not Predictive of acut e renal failure or central nervous system manifestations of toxicity. If on ly ethylene glycol values are available (measured or calculated), an initia l anion gap >20 mmol/L is 95.6% sensitive and 94.4% specific,for acute rena l failure when ethylene glycol is present. Likewise, initial pH <7.30 is 10 0% sensitive and 88.5% specific for acute renal failure. Conclusion: We pro pose glycolic acid >8 mmol/L as a criterion for the initiation of hemodialy sis in ethylene glycol ingestion. Patients with glycolic acid <8 mmol/L pro bably do not need dialysis, regardless of the ethylene glycol concentration , it,hen metabolism of ethylene glycol is therapeutical inhibited. In the a bsence of glycolic acid values, an anion gap >20 mmol/L or PH <7.30 predict s acute renal failure.