Transaminase and Creatine Kinase Ratios for Differentiating Delayed Acetaminophen Overdose from Rhabdomyolysis

Abstract

IntroductionRhabdomyolysis and delayed acetaminophen hepatotoxicity may be associated with elevated serum transaminase values. Establishing the cause of elevated transaminases may be especially difficult because of limited or inaccurate histories of acetaminophen ingestion. We hypothesized that the comparative ratios of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine kinase (CK) can differentiate acetaminophen hepatotoxicity from rhabdomyolysis.MethodsA retrospective chart review of patients in four hospitals from 2006 to 2011 with a discharge diagnosis of acetaminophen toxicity or rhabdomyolysis was performed. Subjects were classified into three groups: rhabdomyolysis, acetaminophen overdose (all), and acetaminophen overdose with undetectable serum acetaminophen concentrations [acetaminophen(delayed)]. Ratios of AST, ALT, and CK were compared using non-parametric statistical methods.Results1,353 subjects were identified and after applying our exclusion criteria there were 160 in the rhabdomyolysis group, 68 in the acetaminophen overdose (all) group, and 29 in the acetaminophen (delayed) group. The AST/ALT ratio for the rhabdomyolysis group was 1.66 (Interquartile range: 1.18–2.22), for the acetaminophen overdose (all) group was 1.38 (1.08–1.69, statistically lower than the rhabdomyolysis group, p = 0.018), and for the acetaminophen (delayed)group was 1.30 (1.06–1.63, p = 0.037). CK/AST ratios were 21.3 (12.8–42.2), 5.49 (2.52–15.1, p < 0.001), and 3.80 (1.43–13.8, p < 0.001) respectively. CK/ALT ratios were 37.1 (16.1–80.0), 5.77 (2.79–25.2, p < 0.001), and 5.03 (2.20–17.4, p < 0.001) respectively. Increasing CK to transaminase ratio cutoffs resulted in increasing test sensitivity but lower specificity.ConclusionAST/ALT, CK/AST and CK/ALT ratios are significantly larger in rhabdomyolysis when compared to patients with acetaminophen toxicity. This result suggests that the ratios could be used to identify patients with rhabdomyolysis who otherwise might have been diagnosed as delayed acetaminophen toxicity. Such patients may not require treatment with N-acetylcysteine, resulting in cost savings and improved resource utilization.

AST/ALT ratio as a predictor of mortality and future exacerbations of PM/DM-ILD——a retrospective cohort study with 522 cases

“…[27] Secondly, PM/DM is characterized by autoimmune conditions that target muscles to some degrees [28], and elevated serum CK, AST, ALT levels have been associated with increased levels of injury to skeletal muscle. [27,29] The positive association of CK with the DRR in our cohort provides support for this mechanism. What's more, pulmonary infection, mainly bacterial, is the most common cause of acute exacerbation in patients with ILD.…”

Case report: Severe rhabdomyolysis and acute liver injury in a high-altitude mountain climber

“…It has been reported that a CK/AST and CK/ALT ratio lower than the cutoff point of 15–20 is helpful in diagnosing concurrent hepatic injury in rhabdomyolysis. The ratio of CK/AST (11.7) and CK/ALT (14.9) in this patient was less than 15, pointing to the presence of acute liver injury ( 18 ). The R value (the ratio of ALT to alkaline phosphatase) was 9.8, suggestive of predominant hepatocellular rather than cholestatic hepatitis.…”

AST/ALT ratio as a predictor of mortality and exacerbations of PM/DM-ILD in 1 year—a retrospective cohort study with 522 cases

“…First, prolonged hypoxemia, caused by exacerbation of diffusing capacity for carbon monoxide (DLco), that is further increased with the development of ILD may result in increased pulmonary artery pressures, leading to increased right ventricle afterload, which promotes hepatocyte injury and AST level increased more [ 27 ]. Secondly, PM/DM is characterized by autoimmune conditions that target muscles to some degrees [ 28 ], and elevated serum CK, AST, and ALT levels have been associated with increased levels of injury to the skeletal muscle [ 27 , 29 ]. The positive association of CK with the DRR in our cohort provides support for this mechanism.…”