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

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. © 2019, Journal of Comprehensive Pediatrics