Abstract
Background: Late onset sepsis (LOS) remains a significant source of morbidity and mortality in extremely low birth weight (ELBW) infants. Early and accurate diagnosis is very important but is difficult due to the similarities in clinical manifestation between the causative microorganisms. We tried to identify the differences between causative microorganisms in clinical and laboratory findings, when sepsis was suspected in ELBW infants.Methods: A retrospective study was conducted on preterm infants born at less than 28 weeks of gestation with a birth weight of less than 1,000 g between January 2009 and December 2019. Clinical and laboratory findings of suspected LOS were assessed. We classified them into three groups according to blood culture results (gram-positive, gram-negative, and fungal groups) and compared them. Results: A total of 107 patients were included after using the exclusion criteria, with 45 (31.5%) in the gram-positive group, 35 (17.5%) in the gram-negative group, and 27 (11.5%) in the fungal group. There were no significant differences in mean gestational age, birth weight, and neonatal morbidities, except for the age of onset, which was earlier in the fungal group than in the bacterial groups. White blood cell (WBC) counts were the highest in the gram-negative group and the lowest in the fungal group. The mean platelet counts were significantly lower in the fungal group (137,000/mm3, 100,000/mm3, and 61,000/mm3 in the gram-positive, gram-negative, and fungal groups, respectively; p< 0.001). C-reactive protein (CRP) levels were significantly higher in the gram-negative group, while glucose was significantly higher in the fungal group. Conclusion: In conclusion, we showed that there are some differences in laboratory findings, according to causative microorganisms, in the LOS of ELBW infants. WBC and CRP were increased in gram-negative infection, and thrombocytopenia and hyperglycemia were predominant in fungal infection. These data may be helpful for choosing empirical antibiotics when sepsis is suspected.