|SOFT - TIAFT 1998||Scientific Session 4||Thursday October 8, 1998|
|UNUSUALLY HIGH BLOOD BENZOYLECGONINE CONCENTRATIONS IN CASES WITH RENAL FAILURE|
|Daniel S. Isenschmid, Graegar M. Smith, Bradford R. Hepler and Sawait Kanluen|
Wayne County Medical Examiners Office, 1300 E Warren, Detroit, MI 48207, USA
|Over a two year period 23 out of 75 decedents (31%) where chronic renal failure or end stage renal disease was considered either a primary or secondary cause of death were found to be positive for cocaine and/or metabolites by GC/MS in appropriately preserved blood specimens. The average blood benzoylecgonine concentration in all cases was 5.1 mg/L (N = 23, cutoff = 0.050 mg/L). Only 8 cases contained ±2.0 mg/L benzoylecgonine (mean = 0.31 mg/L, range = 0.065-0.60). 15 cases (65% of those positive) contained benzoylecgonine at concentrations exceeding 2.0 mg/L with 5 cases (22% of those positive) exceeding 10 mg/L (mean = 7.6 mg/L, range = 2.1-23 mg/L). Parent cocaine was detected in the blood of only four cases (cutoff = 0.025 mg/L, mean = 0.13, range = 0.043-0.26 mg/L) and in only one case where the benzoylecgonine concentration exceeded 10 mg/L. Only one case contained ethyl alcohol (0.03%) and ethyl cocaine was not detected in all 23 cases (cutoff = 0.025 mg/L).
Homicide cases were studied for the same period as controls. In contrast to the population with renal disease, cocaine was frequently detected and benzoylecgonine concentrations were much lower. Out of 980 homicide cases, 184 (19%) were positive for cocaine and/or metabolites above the cutoff in the blood. The average blood benzoylecgonine concentration in these cases was 1.2 mg/L (N = 184, range = 0.051-7.2). Only 30 cases (16% of those positive) contained benzoylecgonine above 2.0 mg/L and only 6 cases (3.3% of those positive) above 5.0 mg/L. Parent cocaine was detected in the blood 143 (78%) of the cases positive for benzoylecgonine (mean = 0.25, range = 0.025-7.2) and in ALL 30 cases containing benzoylecgonine above 2.0 mg/L. Ethyl alcohol and ethyl cocaine (mean = 0.094, range = 0.025-0.41) were detected in 87 and 67 cases, respectively.
These findings suggest that in patients with chronic renal failure or end stage kidneys, the polar cocaine metabolite, benzoylecgonine, may accumulate to unusually high concentrations. Careful consideration should be given to the role cocaine abuse may play in patients with renal failure. While cocaine has not been shown to be inherently nephrotoxic, this data supports findings by other investigators who have demonstrated that cocaine users are subject to renal disease. However, in the cases discussed here cocaine toxicity was thought to play a primary role in the cause of death in only a single case and to be contributing in only 4 cases. Based on the association of cocaine abuse with renal disease, the role of cocaine abuse may have been considerably undereported in these cases. Finally, consideration should also be given to the toxicity of benzoylecgonine. Although not centrally active, benzoylecgonine has been reported to have potentially deleterious effects on the vasculature.