Peritoneal Fluid Cytology in Clinical Cases of Bovine Obstructive Urolithiasis

Thirty clinical cases of obstructive urolithiasis, 15 with intact urinary bladder and 15 with ruptured urinary bladder, were used to study the changes in peritoneal fluid cytology. The percentage of neutrophils was highly increased than the normal reference range reported for cattle with slight decrease in lymphocyte percentage. The value for neutrophil percent was almost similar in both intact and ruptured urinary bladder cases. The monocyte/mesothelial cells/macrophage percent, though increased than the normal reference range were identical in both the groups. There was a predominant decrease in eosinophil percentage with more decrease in intact urinary bladder cases. Polymorphonuclear-to-mononuclear cell ratio was same in both the groups, but higher than the normal reference value (1:1). Eosinophils ≤ 8% and neutrophil ≥ 30% could be established as a reference range of peritonitis in calves. Red blood corpuscles (RBCs) were totally absent in the peritoneal fluid samples obtained from intact urinary bladder cases except in one case. However, in the peritoneal fluid samples obtained from ruptured urinary bladder cases, RBCs were found in abundance in 3 cases and very few in 2 cases. The morphology and the different cell type present in the peritoneal fluid samples also varied according to the status of urinary bladder. In intact urinary bladder cases, neutrophils were mature and nondegenerate, while in ruptured urinary bladder cases degenerate and hypersegmented neutrophils were more. Mesothelial cells were equally distributed in both the groups. Bacteria were found extracellularly as well as intracellularly in degenerate neutrophils in 4 cases with ruptured urinary bladder and only extracellularly in 2 cases with intact urinary bladder. Peritoneal fluid cytology can be used for differentiation of peritonitis from normal cases and non septic peritonitis from septic peritonitis besides diagnosing the uroperitoneum in calves.