Alterations in serum activity of hepatocellular enzymes, levels of liver function markers, and liver histology of dogs given high (nephrotoxic) doses of gentamicin

This study evaluated the effects of nephrotoxic doses of gentamicin on serum activity of hepatocellular enzymes, levels of liver function markers, and liver histology of dogs. Nine dogs, randomly assigned to two groups (A and B) of five and four dogs each, were used for the study. Baseline values for kidney function, hepatocellular, hepatobiliary, and liver function parameters were assayed initially. Gentamicin injections (100 mg/kg) were given intravenously daily for 10 days to the dogs in Group A, while the Group B dogs served as the untreated control. After the 10 days of injections, blood was collected from the dogs for re-assay of the serum biochemistry. Liver and kidney tissues were processed for histopathology. Results showed that in addition to the significant ( p < 0.01) increase in serum levels of creatinine (14-fold), urea (3-fold), and uric acid (4-fold) in the Group A dogs following the gentamicin injections, there were significant ( p < 0.01) multiple fold increases in the serum activities of alanine aminotransferase 6-fold), aspartate aminotransferase (5-fold), alkaline phosphatase (3-fold), and serum bilirubin levels (5-fold). In both Group A and B dogs, there were no significant alterations ( p > 0.05) in the levels of serum proteins and total cholesterol after the injections. Histological study revealed severe damage to the liver and kidney parenchyma in the Group A dogs only. It was concluded that in addition to kidney damage, the administration of nephrotoxic doses of gentamicin to dogs led to significant hepatocellular and hepatobiliary damage, but had no significant effect on the hepatic synthetic function (serum levels of total cholesterol, total proteins, albumin and globulins). Due consideration should be given to the effects of gentamicin on the liver when higher doses are used experimentally or clinically in dogs.