A comparative study on ascetic fluid biochemical markers in cirrhotic children with and without spontaneous bacterial peritonitis: A cross-sectional observation

Abstract

Background: Cirrhotic ascites is frequently complicated with spontaneous bacterial peritonitis (SBP). Objectives: Here, we assessed the diagnostic validity of some inflammatory markers in children with SBP. Methods: This cross-sectional study was performed in the Pediatric Gastroenterology Ward of Namazi hospital of Shiraz. SBP was considered as ≥ 250 polymorphonuclear cell (PMN) /µL ascetic fluid (AF). Results: Out of 150 liver cirrhotic patients with ascites, 41 (27.3%) were diagnosed with SBP. Mean WBC count and PMN per µL of AF were significantly higher in SBP patients than non-SBP (P < 0.0001). The highest specificity for the diagnosis of SBP was recorded for AF smear test (100%). Positive AF smear and culture tests rendered the highest positive predictive values (PPV, 100% and 88.2% respectively). The highest negative predictive value (NPV) was related to AF leukocyte esterase test (94.2%). The highest area under the curve (AUC) for diagnosis of SBP belonged to WBC count (0.956), total cell count (0.817), and LDH concentration (0.814) of AF. A cut off value of 290 WBC per µL AF resulted in respective 95.1% and 88.1% sensitivity and specificity. Trespass of WBC count and lactate dehydrogenase (LDH) level of AF higher than cutoff values (290 cells/µL, and 175 (u/L), respectively) resulted in 82.9%, 92.7%, 81%, and 93.5% sensitivity, specificity, PPV and NPV, respectively. Conclusions: Total cell and WBC counts of AF strongly correlated with ascetic PMN count. Ascetic LDH, alone or in combination with WBC count of AF can be used as a potential surrogate for PMN counts in diagnosis of SBP.