Rhabdomyolysis in patients following opioid overdose

Abstract

Rhabdomyolysis is a clinical entity characterized by the destruction of skeletal muscle with the resultant release of intracellular enzymatic content into the bloodstream, leading to systemic complications. This study aimed to determine the clinical and some of the biochemical findings in patients with rhabdomyolysis following opioid overdose. Methods: This study randomly recruited 140 patients suffering from rhabdomyolysis due to acute intoxication and was implemented for one year at the University Clinic for Toxicology. Rhabdomyolysis was defined as a creatine phosphokinase (CK) >250 U/L according to poisoning severity score (PSS). We included adult patients ≥ 18 years of age. We excluded patients with myocardial infarction, renal impairment, acute and chronic hepatitis B and C, and other hepatic impairments, based on the medical history. Results: Out of a total of 140 patients with rhabdomyolysis due to acute intoxication, 14.2 % (n=20) were opioid overdose (male n=19; female n=1). The average age of methadone patients was 36.7±6.6 and in heroin patients 33.6±9.3. On the first, third, and fifth days, serum creatine kinase (CK) values in heroin patients were 8925 vs. 6404.5 vs. 996 U/L, and for methadone overdose 5548.3 vs. 10300 vs. 2114 U/L. Severe rhabdomyolysis according to the PSS score occurs in methadone overdose 46.67% (n=7), and in heroin overdose 40% (n=2). Moderate rhabdomyolysis was observed in heroin overdose 40% (n=2) and in methadone overdose 40% (n=6). For mild rhabdomyolysis, we determined a heroin overdose of 20% (n=1) and a methadone overdose of 13.33% (n=2). Determined values of hs-cTnI in methadone overdose were (n=5) 279.7±190.7 µg/L, and in heroin overdose were (n=4) 78.48±28.88 µg/L. On the first, third, and fifth day, AST values in heroin overdose were 823 vs. 415 vs. 93.5 U/L, and for methadone 242 vs. 420 vs. 285 U/L. In the three measurement times, the highest values of urea in heroin patients were 10.1 vs. 27.2 vs. 20.2 mmol/L, and methadone 6.3 vs. 23 vs. 11.3 mmol/L, the highest values for creatine were in heroin 228 vs. 405.5 vs. 302.5 µmol/L and methadone overdose 108 vs. 199.8 vs. 483.5 µmol/L. Acute kidney injury (AKI) occurred in 21 patients of which heroin was 14.2% (n=3) and 28.5% (n=6) methadone. Renal replacement therapy was applied in 13 patients of which 15.3% (n=2) in heroin and 30.7% (n=4) in methadone overdose. Conclusion: Physicians should be aware that severe and moderate rhabdomyolysis occurs more often in patients with methadone and heroin overdose. Increased levels of CK, high-sensitivity troponin I, AST, urea, and, creatine were associated with opioid overdose and should be identified to initiate appropriate treatment. Acute kidney injury is a common complication in heroin and methadone overdose patients and often there is a need for renal replacement therapy.