Background: Pseudomonas aeruginosa (P.A) is the leading agent in nosocomial infections. Multi-drug resistance is the main problem of P.A infections especially in cystic fibrosis, chronic bronchitis, skin infection and burned patients infection. Thus paying more attention to the pathogenetic mechanisms of Pseudomona is crucial for its prevention and control.
Method & Material : In this survey, 81 blood samples of healthy adults, neonates, ill children and premature babies were withdrawn. After the isolation of neutrophils with standard methods and culturing with pseudomonas in culture media with 1,2,3,4 McFarland tube concentrations, we interacted neutrophils and exotoxins for 15, 30, 45, and 60 minutes. Then we performed NBT test and evaluated the range of Pseudomonas exotoxins action on neutrophil apoptosis.
Result: Apoptosis was 100% in healthy adults, 81.8% in ill children, 90.8% in neonate and 51.9% in premature group. We observed no apoptosis in 1 and 2 McFarland. The 3 McFarland revealed 12.5% growth in healthy cases, 4.7% in ill children and 1% in neonate and premature. The mean apoptosis was time dependent among cases with the 68.5% apoptosis in healthy cases, 92.5% in immunocompromised, 94.7% in neonate and 98.6% in premature all at the end of first 15 minute. Analysis of apoptosis after 30 minute reveals significant differences in premature and other groups (0% Vs 6% of healthy, 5.2% of immunocompromised and 7.2% of neonate) (P<0.04).
Discussion: Current study discloses the role of Pseudomonas exotoxins on acceleration of neutrophil apoptosis in a time dependent manner. This effect is more significant in ill children and neonate cases.