Tracking Changes of Lymphocyte Subsets and Pre‐inflammatory Mediators in Full‐term Neonates with Suspected or Documented Infection

Abstract

Investigation was made of changes in immune system parameters during the course of neonatal infection. The study population consisted of 95 full‐term neonates matched for chronological age and sex, divided into three groups: suspected infection (n = 20), sepsis (n = 25), infection‐free control subjects (n = 50). Serial measurements were made of the cytokines interleukin‐6 (IL‐6), interleukin‐1b (IL‐1b) and tumour necrosis factor‐α (TNF‐α), lymphocyte subsets [CD3+, CD4+, CD8+, natural killer (NK) cells and B cells], the immunoglobulins (Ig) (IgG, IgM and IgA), C‐reactive protein (CRP), and the total blood count, before, 2 days after initiation of treatment and after stopping treatment (time periods first, second and third, respectively). IL6, TNF‐α, IL1‐b and CRP were higher at the first time period in the sepsis group, and IL6 and TNF‐α continued to be higher in this group at the second period. IL‐6 and TNF‐α were precise sepsis predictors with sensitivity and specificity of 0.92, 0.98 and 0.91, 0.92, respectively. NK cells, B cells, CD3+, CD4+, CD8+ were higher in the sepsis and suspected infection groups, but the ratios CD3+/CD4+, CD3+/CD8+, CD4+/CD8+ showed no difference from the controls. IgG was lower and IgM higher in the sepsis group. In the control subjects CD3+, CD4+, CD8+ lymphocytes increased with increasing age. It is concluded that IL‐6 and TNF are good diagnostic markers of sepsis in full‐term neonates. Lymphocyte subsets were affected by both the clinical condition and the chronological age. NK and B cells may be elevated in suspected and documented sepsis, and further studies are needed to determine their clinical significance.

Pre-inflammatory Mediators and Lymphocyte Subpopulations in Preterm Neonates with Sepsis

“…Aygun et al found levels of CD3+, CD4+, and CD8+ in 12 neonates with proven sepsis similar to those of control subjects in absolute numbers, but a lower percentage of total lymphocytes and CD4+ [24]. Hotoura et al found higher CD3+, CD4+, and CD8+ in full-term neonates with sepsis, but their ratios did not differ from those of controls [15]. In the present study, similar percentages of CD3+, CD4+, and CD8+ were found in the neonates with sepsis and controls.…”

“…This observation is in agreement with the findings of the present study, where a combination of CRP >10 mg/ l with a TNF-α >30 pg/ml or IL-6 >30 pg/ml was shown to offer the best diagnostic value for sepsis in the preterm neonates. A recent study in this center showed that in full-term neonates, IL-6 and TNF-α were good diagnostic markers of sepsis with no need for combination with CRP [15]. CRP >10 mg/l was a specific but not sensitive index.…”

“…The neonates with sepsis in the present study had elevated percentages of NK and B cells. Full-term neonates with sepsis or suspected infection have been found to have an increase in NK cells and also a significant increase in B cells [15]. Upregulation of many surface activation markers on peripheral bloodderived T cells, monocytes, and NK cells was recently found in neonates with sepsis [28].…”

Healthcare Associated Infection in the Neonatal Intensive Care Unit of King Abdl Aziz Specialist Hospital, Taif, KSA

“…Deficiencies of both innate and adaptive immunity contribute to the impaired neonatal host defense [3]. A domination of naive immune cells, functional impairments and lower leukocyte subset numbers contribute further to an increased susceptibility [4,5]. The mode of infection transmission is mainly through the care-giver staff specially if the proper antiseptic measures are not considered [4].…”

“…A domination of naive immune cells, functional impairments and lower leukocyte subset numbers contribute further to an increased susceptibility [4,5]. The mode of infection transmission is mainly through the care-giver staff specially if the proper antiseptic measures are not considered [4]. Infection control for preventing nosocomial infections may play an important role in reducing medical costs, period of hospital stay, and mortality in hospitalized patients [6].…”