Neutrophil CD64 Index Research Articles

Chronic alcohol exposure, infection, extended circulating white blood cells differentiated by flow cytometry and neutrophil CD64 expression: a prospective, descriptive study of critically ill medical patients

BackgroundA history of prolonged and excessive consumption of alcohol increases the risk for infections. The goal of this study was to investigate circulating white blood cells (WBC) differentiated by flow cytometry and neutrophil CD64 expression in excessive alcohol drinkers versus abstinent or moderate drinkers, and in those with or without infection, in medical patients admitted to the intensive care unit (ICU).MethodsAll patients admitted between September 2009 and March 2010 with an ICU-stay of 3 days or more were eligible for inclusion. Upon admission, hematological exams were conducted by flow cytometry.ResultsOverall, 281 adult were included, with 37% identified as at-risk drinkers. The only significant difference found in circulating WBC between at-risk and not-at-risk drinkers was a lower number of B lymphocytes in at-risk drinkers (P = 0.002). Four groups of patients were defined: not-at-risk drinkers with no infection (n = 66); not-at-risk drinkers with infection (n = 112); at-risk drinkers with no infection (n = 53); and at-risk drinkers with infection (n = 50). Whilst the presence of infection significantly reduced levels of noncytotoxic and cytotoxic T lymphocytes and significantly increased levels of CD16– monocytes in not-at-risk drinkers, with variation related to infection severity, infection had no effect on any of the variables assessed in at-risk drinkers. Post-hoc comparisons showed that B-lymphocyte, noncytotoxic, and cytotoxic T lymphocyte and CD16– counts in at-risk drinkers were similar to those in not-at-risk drinkers with infection and significantly lower than those in not-at-risk drinkers without infection. Neutrophil CD64 index varied significantly between groups, with variations related to infection, not previous alcohol consumption.ConclusionsThese results show that chronic alcohol exposure has an impact on the immune response to infection in critically ill medical patients. The absence of significant variations in circulating WBC seen in at-risk drinkers according to the severity of infection is suggestive of altered immune response.

Neonatal Sepsis: past, present and future; a review article

Sepsis is the most common cause of neonatal mortality. As per National Neonatal Perinatal Database (NNPD) 2002-2003, the incidence of neonatal sepsis in India was 30 per 1000 live birth. It is 3% among intramural babies and 39.7% among extramural admissions. The early manifestations of neonatal sepsis are vague and ill-defined. Novel approaches in the diagnosis of neonatal sepsis include heart rate analysis on ECG or colorimetric analysis of skin color. Although blood culture is the gold standard for the diagnosis of sepsis, culture reports would be available only after 48-72 hours. In this era of multidrug resistance, it is mandatory to avoid unnecessary use of antibiotics to treat noninfected infants. Thus, rapid diagnostic test(s) that differentiate infected from non-infected infants, particularly in the early newborn period, that include Interleukien-6 (IL-6), neutrophil CD64 index, procalcitonin and nucleated RBC count, have the potential to make a significant impact on neonatal care. The aim of this review is to specify the diagnostic criteria, treatment guidelines and a summary of the newer diagnostic tests of sepsis. KEY WORDS: Sepsis; Intramural; Extramural; Multidrug resistance

Neutrophil and monocyte CD64 indexes, lipopolysaccharide-binding protein, procalcitonin and C-reactive protein in sepsis of critically ill neonates and children

To compare the diagnostic accuracy of neutrophil and monocyte CD64 indexes (CD64in and CD64im) for sepsis in critically ill neonates and children with that of lipopolysaccharide-binding protein (LBP), procalcitonin (PCT) and C-reactive protein (CRP). Prospective, observational study in a level III multidisciplinary neonatal and pediatric intensive care unit (ICU). Forty-six neonates and 36 children with systemic inflammatory response syndrome (SIRS) and suspected infection, classified into two groups: those with bacterial sepsis (microbiologically proven or clinical sepsis) and those without bacterial sepsis (infection not supported by subsequent clinical course, laboratory data and microbiological tests). Flow cytometric CD64in and CD64im, serum LBP, PCT and CRP measurement on 2 consecutive days from admission to the ICU. There were 17 cases of bacterial sepsis in neonates and 24 cases of bacterial sepsis in children. All neonates and the majority of children were mechanically ventilated, and more than two-thirds of neonates with sepsis and one-third of children with sepsis needed inotropic/vasopressor drugs. The highest diagnostic accuracy for sepsis on the 1st day of suspected sepsis was achieved by LBP in neonates (0.86) and by CD64in in children (0.88) and 24 h later by CD64in in neonates (0.96) and children (0.98). Neutrophil CD64 index (CD64in) is the best individual marker for bacterial sepsis in children, while in neonates the highest diagnostic accuracy at the time of suspected sepsis was achieved by LBP and 24 h later by CD64in.

Laboratory diagnosis of neonatal sepsis

Laboratory diagnosis of neonatal sepsis continues to be a confusing issue- numerous tests but most of them lacking precise sensitivity and specificity. Simple blood counts are easy to do but are not specific while the band count and I:T ratio assessment needs an expert, making it difficult to be used routinely. CRP is a simple investigation but one should understand its pitfalls so that it is judiciously used. Indiscriminate use of CRP is leading to widespread antibiotic overuse and development of resistant organisms. Interleukin 6, neutrophil CD64 index, procalcitonin and NRBC count are some promising newer screening tests which are being evaluated. Automated blood cultures have proved to be very sensitive and rapid in reporting compared to conventional blood cultures. Finally PCR of 16s rRNA gene along with bacterial probes has found its place in the diagnosis of sepsis with a high degree of accuracy. A combination of screening tests along with the clinical signs is useful to initiate antibiotics while the duration or cessation of antibiotics should be guided by the blood cultures.