Expression of Myoglobin in the Urine of Cocaine Users

Background: The possibility exists that cocaine use in the absence of frank clinical presentation of acute cardiac events may be associated with subclinical injury including the release of myoglobin which is a nonspecific marker for cardiac and skeletal muscle damage. Objectives: This investigation examined urine specimens for potential differences between cocaine use and the expression of myoglobin (a marker associated with cardiovascular damage, inflammation and oxidative stress). Methods: 40 urine specimens were assayed for cocaine metabolites, creatinine, total protein (BSA) and myoglobin using ELISA and colorimetry. Results: We observed significant differences between male control and male cocaine positive urines for myoglobin. Interestingly, there was no statistically significant difference in females between control and cocaine positive urines. Conclusion: Differences in the urinary expression of myoglobin may be important in evaluating the gender based effects of cocaine use and may have potential clinical applications which may be related to gender differences in signs and symptoms of cocaine toxicity.