Association of Bacteriuria with the Presence of Nitrite and Pus Cells
Zenoh Danjuma, Thumamo Pokam, Kashibu Emmanuel, Babylon Philemon, Yakubu Nosano
Int. J. Bio. Lab. Sci  2018  1&2:9-14 Abstract】 PDF

This study attempts to investigate the level of association of bacteriuria with the presence of nitrite and pus cells in urine. Methodology: Over 220 subjects were examined; 20 mL of mid-stream urine was collected and cultured on CLED and Blood agar using a calibrated wire loop of 0.001 mL, then analyzed using combi 9 rapid test kits. About 5mL was centrifuge at 2000rpm for 5 minutes and the sediment was examined with a microscope. Results: Of the 220 subjects examined, 143(65%) yielded bacterial growth, 35(24%) with a count of ≤103 CFU/mL, 46(32%) with 104 CFU/mL, and 62(43%) had ≥105 CFU/mL. Nitrite was present in 54/220(26%) of the samples, and 43(80%) were culture positive; it has a sensitivity of 30% and specificity of 80. Pyuria was detected in 102/220(46%) samples, with 61(60%) yielding positive culture, the sensitivity and specificity were 43% and 60% respectively. Thirty-four (24%) of 143 subjects with positive culture, had both pyuria and nitrite in their urine, and 27(44%) and 7(21%) were positive for only pyuria and nitrite respectively. Statistical analysis showed a lack significant association between; bacteriuria and the presence of nitrite (P=0.13); between pyuria and bacteriuria (P=0.064). The occurrence of both pyuria and nitrite, was strongly linked to bacteriuria (P=0.0003). Conclusion: The presence of both pus cells and nitrite in urine signifies UTIs, but the occurrence of only one of the parameters are not reliable, and the absence of anyone or both parameters does not rule out UTIs.
Key words: Urinary Tract Infection (UTIs), Pyuria, Nitrite, Bacteriuria, mid-stream urine, Colony forming unit (CFU/mL)