Evaluation of neutropenia and neutrophilia in hospitalized preterm infants

The effect of leucocytosis on retinopathy of prematurity

Postnatal leukocytosis reflects the general condition of inflammatory. Infection and inflammatory reaction have been proven to affect the occurrence of ROP and other visual dysfunction. Infants with a gestational age of < 28 weeks who were less than three days of age and admitted to the hospital between September 2015 and March 2021 were included in the study. Infants with a white blood cell (WBC) count ≥ 30 × 109/L were assigned to the leucocytosis group (n = 82). Gestational age- and weight-matched infants without leucocytosis were included as a control group (n = 85). The incidence and prognosis of ROP in preterm infants were compared between the groups. Receiver operating characteristic (ROC) curves were used to analyse the correlation between the WBC count and severe ROP. Compared to the infants in the control group, those in the leucocytosis group had lower 1-min Apgar scores (p < 0.001); higher C-reactive protein (p < 0.001) and procalcitonin (p < 0.001); and higher incidences of intracranial haemorrhage (p = 0.007), leukomalacia (p = 0.045), sepsis (p = 0.006), bronchopulmonary dysplasia (p = 0.017). The maternal age was higher in the leucocytosis group (p < 0.001). After adjusting for gestational age at 45 weeks, the incidence of severe ROP (p = 0.001) and the requirement for ranibizumab injections (p = 0.004) were higher in the leucocytosis group. The cut-off WBC count was determined to be 19.1 × 109/L, with a sensitivity of 88.6%, a specificity of 77.3%, and an area under the curve of 0.941 (95% confidence interval: 0.904-0.978) for the detection of severe ROP. Leucocytosis may be associated with severe ROP in premature infants.

Maternal Hypertension and Early-Onset Neonatal Neutropenia

Objective: Maternal hypertension is considered a risk factor for early neonatal neutropenia. We sought to explore this relationship. Study Design: This retrospective cohort study compared initial neutrophil counts in infants born to mothers with preeclampsia with severe features (PSF) and infants born to normotensive mothers using Negative Binomial Regression (NBR) and logistic regression models. Results: Maternal hypertension negatively affected the early neonatal neutrophil count (adjusted NRB coefficient 0.4 [0.2, 0.6], p < 0.0001) but did not increase the risk of neutropenia (OR 2.07 [0.97, 4.41], p = 0.06). The initial neutrophil count and neutropenia risk were not different between PSF subgroups. Gestational age had the greatest impact on neutropenia risk (OR 0.72 [0.64, 0.81], p < 0.0001). Almost all neutropenia resolved within 48 h. Conclusion: Maternal hypertension negatively affects the early neonatal neutrophil count while not increasing the risk of neonatal neutropenia.

A novel marker for predicting type 1 retinopathy of prematurity: C-reactive protein/albumin ratio

PURPOSE

We aimed to investigate whether the C-reactive protein (CRP) to albumin ratio (CAR) an inflammatory predictor can be used as a marker for the development of ROP.

METHODS

Gestational age, birth weight, gender, neonatal, and maternal risk factors were recorded. The patients were divided into two groups: those who did not develop ROP (ROP -) and those who developed ROP (ROP +). The ROP + group was further separated into two groups: those who required treatment (ROP + T) and those who were not treated (ROP + NT). The following parameters were noted in the first postnatal week and at the end of the first postnatal month: CRP, albumin, CAR, white blood cell (WBC), neutrophil, lymphocyte, neutrophil-to-lymphocyte ratio (NLR), distribution red cell width (RDW), platelet (Plt), and RDW/platelet ratio.

RESULTS

We evaluated 131 premature infants who met the inclusion criteria. There was no difference between the main groups in hemogram parameters and CAR at the postnatal first week. WBC count (p = 0.011), neutrophil count (p = 0.002), and NLR were high (p = 0.004) in the ROP + group at the end of the postnatal 1st month. The CAR level at the end of the first month was higher in the ROP + group (p = 0.027). CAR was similar between the ROP + T and ROP + NT groups (p = 0.112) in the postnatal first week but higher in the treatment-required group at the end of the first month (p < 0.01).

CONCLUSION

High CAR and high NLR at the end of the postnatal first month can be used to predict the development of severe ROP.

Leukopenia and Neutropenia at Birth and Sepsis in Preterm Neonates of <32 Weeks' Gestation

OBJECTIVE

This study aimed to evaluate associations between leukopenia or neutropenia at birth and risk of sepsis in very preterm neonates.

STUDY DESIGN

We conducted a retrospective unmatched cohort study of neonates of <32 weeks' gestation. Those with leukopenia (≤5,000/µL) were compared with a unmatched cohort without leukopenia. Comparisons were also made for patients with neutropenia and without neutropenia. The outcomes were early-onset sepsis, late-onset sepsis, and mortality.

RESULTS

We identified 271 neonates with leukopenia at birth and 271 without. Multivariable analyses identified higher odds of early-onset sepsis (adjusted odds ratio [AOR] = 4.85, 95% confidence interval [CI]: 1.29-18.20) in leukopenic neonates. Of neonates with leukopenia, 183 had both leukopenia and neutropenia and were associated with the highest odds of early-onset sepsis (AOR = 6.94, 95% CI: 1.77-27.15) compared with those with neither or with either alone.

CONCLUSION

Leukopenia, neutropenia, and both leukopenia and neutropenia at birth were associated with early-onset sepsis in very preterm neonates.

KEY POINTS

· Leukopenia and neutropenia combined at birth was associated with highest odds of early-onset sepsis.. · Leukopenia or neutropenia were associated with sepsis in preterm neonates.. · The risk of infection persist throughout neonatal stay in NICU..

Factors associated with severe respiratory syncytial virus disease in hospitalised children: a retrospective analysis

BACKGROUND

Early recognition of children at risk of severe respiratory syncytial virus (RSV) lower respiratory tract infection is important as it informs management decisions. We aimed to evaluate factors associated with severe disease among young children hospitalised with RSV infection.

METHODS

We conducted a retrospective cohort study of all children <2 years of age hospitalised for RSV lower respiratory tract infection at a single tertiary paediatric hospital over three RSV seasons (January 2017-December 2019). We classified children as having 'moderate' or 'severe' disease based on the level of respiratory intervention and used univariable and multivariable regression models to determine factors associated with severe disease.

RESULTS

Of 970 hospitalised children, 386 (40%) were classified as having 'severe' and 584 (60%) as having 'moderate' RSV disease. On multivariable analyses, age <2 months (OR: 2.3, 95% CI 1.6 to 3.3, p<0.0001), prematurity (OR: 1.6, 95% CI 1.1 to 2.4, p=0.02) and RSV-parainfluenza virus type 3 (PIV3) codetection (OR: 2.6, 95% CI 1.05 to 6.5, p=0.04) were independently associated with severe disease.

CONCLUSION

Younger age, prematurity and PIV3 codetection were associated with severe RSV disease in children <2 years of age hospitalised with RSV infection. The association between PIV3 and severe RSV disease is a novel finding and warrants further investigation.

The composition of human vaginal microbiota transferred at birth affects offspring health in a mouse model

Newborns are colonized by maternal microbiota that is essential for offspring health and development. The composition of these pioneer communities exhibits individual differences, but the importance of this early-life heterogeneity to health outcomes is not understood. Here we validate a human microbiota-associated model in which fetal mice are cesarean delivered and gavaged with defined human vaginal microbial communities. This model replicates the inoculation that occurs during vaginal birth and reveals lasting effects on offspring metabolism, immunity, and the brain in a community-specific manner. This microbial effect is amplified by prior gestation in a maternal obesogenic or vaginal dysbiotic environment where placental and fetal ileum development are altered, and an augmented immune response increases rates of offspring mortality. Collectively, we describe a translationally relevant model to examine the defined role of specific human microbial communities on offspring health outcomes, and demonstrate that the prenatal environment dramatically shapes the postnatal response to inoculation.

Complete blood count parameters to predict retinopathy of prematurity: when to evaluate and what do they tell us?

PURPOSE

To evaluate the relationship of novel inflammatory markers neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) with retinopathy of prematurity (ROP) development and requirement for laser photocoagulation (LP) treatment.

METHODS

The charts of infants screened for ROP were reviewed retrospectively, and 120 newborns who had complete blood count (CBC) data in the first 24 hours after delivery (early period) and between 35 and 37th gestational weeks (late period) were included. Study population consisted of 34 infants who required LP for ROP treatment, 52 newborns with ROP that regressed without treatment, and 34 controls who did not developed any ROP stages. Demographics, etiological factors and CBC data including NLR and PLR values were noted. Risk factors for ROP development and treatment requirement were investigated using logistic regression analyses.

RESULTS

Significantly lower NLR was found in ROP cases compared to non-ROP group during late period (p = 0.003), while there was no difference in NLR during early period (p = 0.298). No significant difference was observed in PLR during both early and late periods (p = 0.230 and p = 0.349, respectively). Multivariate analysis revealed daily weight gain as major risk factor for ROP development (p = 0.001; OR: 0.870, 95% CI: 0.799-0.947), and hyperbilirubinemia as an independent risk factor for LP requirement (p = 0.045; OR: 0.204, 95% CI: 0.043-0.966).

CONCLUSION

NLR or PLR does not appear to be predictive risk factors for treatment requirement in cases with ROP. CBC values during first 24 h of life may be misleading; therefore, a late period CBC is recommended to evaluate prognostic factors for ROP development.

Severe respiratory syncytial virus disease in preterm infants: a case of innate immaturity

Respiratory syncytial virus (RSV) is the most common viral pathogen associated with acute lower respiratory tract infection (LRTI) in children under 5 years of age. Severe RSV disease is associated with the development of chronic respiratory complications such as recurrent wheezing and asthma. A common risk factor for developing severe RSV disease is premature gestation and this is largely due to an immature innate immune system. This increases susceptibility to RSV since the innate immune system is less able to protect against pathogens at a time when adaptive immunity has not fully developed. This review focuses on comparing different aspects of innate immunity between preterm and term infants to better understand why preterm infants are more susceptible to severe RSV disease. Identifying early life innate immune biomarkers associated with the development of severe RSV disease, and understanding how these compare between preterm and term infants, remains a critically important question that would aid the development of interventions to reduce the burden of disease in this vulnerable population.

Cardiac and Inflammatory Necrotizing Enterocolitis in Newborns Are Not the Same Entity

Background: Necrotizing enterocolitis (NEC) is an often-fatal neonatal disease involving intestinal hyperinflammation leading to necrosis. Despite ongoing research, (1) conflicting results and (2) comorbidities of NEC patients make early NEC detection challenging and may complicate therapy development. Most research suggests that NEC pathogenesis is multifactorial, involving a combination of (1) gut prematurity; (2) abnormal bacterial colonization; and (3) ischemia-reperfusion (I/R) injury. As neutrophil extracellular traps (NETs) partially mediate I/R injury and drive inflammation in NEC, we hypothesized that NETs contribute to NEC development; particularly in cardiac patients. Methods: A retrospective analysis of baseline characteristics, clinical signs, laboratory parameters, and imaging was conducted for surgically verified NEC cases over 10 years. Patients were stratified into two groups: (1) prior medically or surgically treated cardiac disease (cardiac NEC) and (2) no cardiac comorbidities (inflammatory NEC). Additionally, histology was reassessed for neutrophil activation and NETs formation. Results: A total of 110 patients (cNEC 43/110 vs. iNEC 67/110) were included in the study, with cNEC neonates being significantly older than iNEC neonates (p = 0.005). While no significant differences were found regarding clinical signs and imaging, laboratory parameters revealed that cNEC patients have significantly increased leucocyte (p = 0.024) and neutrophil (p < 0.001) counts. Both groups also differed in pH value (p = 0.011). Regarding histology: a non-significant increase in staining of myeloperoxidase within the cNEC group could be found in comparison to iNEC samples. Neutrophil elastase (p = 0.012) and citrullinated histone H3 stained (p = 0.041) slides showed a significant markup for neonates diagnosed with cNEC in comparison to neonates with iNEC. Conclusion: The study shows that many standardized methods for diagnosing NEC are rather unspecific. However, differing leucocyte and neutrophil concentrations for iNEC and cNEC may indicate a different pathogenesis and may aid in diagnosis. As we propose that iNEC is grounded rather in sepsis and neutropenia, while cNEC primarily involves I/R injuries, which involves neutrophilia and NETs formation, it is plausible that I/R injury due to interventions for cardiac comorbidities results in pronounced neutrophil activation followed by a hyperinflammation reaction and NEC. However, prospective studies are necessary to validate these findings and to determine the accuracy of the potential diagnostic parameters.

Effectiveness of Granulocyte Colony-Stimulating Factor in Hospitalized Infants with Neutropenia

Objective The objective of this study was to determine the time to hematologic recovery and the incidence of secondary sepsis and mortality among neutropenic infants treated or not treated with granulocyte colony-stimulating factor (G-CSF). Study Design We identified all neutropenic infants discharged from 348 neonatal intensive care units from 1997 to 2012. Neutropenia was defined as an absolute neutrophil count ≤ 1,500/µL for ≥ 1 day during the first 120 days of life. Incidence of secondary sepsis and mortality and number of days required to reach an absolute neutrophil count > 1,500/µL for infants exposed to G-CSF were compared with those of unexposed infants. Results We identified 30,705 neutropenic infants, including 2,142 infants (7%) treated with G-CSF. Treated infants had a shorter adjusted time to hematologic recovery (hazard ratio: 1.36, 95% confidence interval [CI]: 1.30-1.44) and higher adjusted odds of secondary sepsis (odds ratio [OR]: 1.50, 95% CI: 1.20-1.87), death (OR: 1.33, 95% CI: 1.05-1.68), and the combined outcome of sepsis or death (OR: 1.41, 95% CI: 1.19-1.67) at day 14 compared with untreated infants. These differences persisted at day 28. Conclusion G-CSF treatment decreased the time to hematologic recovery but was associated with increased odds of secondary sepsis and mortality in neutropenic infants. G-CSF should not routinely be used for infants with neutropenia.

Early-Onset Neutropenia in Small-for-Gestational-Age Infants

BACKGROUND

Early neutropenia is more common in small for gestational age (SGA) neonates (birth weight <10th percentile) than in appropriately grown neonates. However, several aspects of this variety of neutropenia are unknown, including the duration, kinetic mechanism, and outcomes.

METHODS

Using 10 years of multihospital records, we studied SGA neonates who, during the first week after birth, had neutrophil counts <1000/μL.

RESULTS

This degree of neutropenia was more common in SGA neonates (6%, 207/3650) than in non-SGA matched controls (1%, 46/3650; P < .001). Neutrophil counts stayed below the lower reference interval for 7 days. Ratios of immature to total neutrophils were within the reference interval, suggesting reduced neutrophil production, not accelerated neutrophil use or destruction. Increased nucleated red cells at birth correlated with decreased neutrophils (P < .001). Neutropenia was not independently associated with maternal hypertensive disorders, over and above the effect of SGA. Of 201 neutropenic SGA neonates, 129 (64%) also had thrombocytopenia. Sixteen percent of neutropenic neonates were treated with recombinant granulocyte colony-stimulating factor (rG-CSF) or intravenous immunoglobulin (IVIG), with no reduction in late-onset sepsis or necrotizing enterocolitis (NEC). Regression analysis showed that neutropenia (but not thrombocytopenia in the absence of neutropenia) was independently associated with increased odds of developing necrotizing enterocolitis (odds ratio 4.01, 90% confidence interval 2.08 to 7.35, P < .001).

CONCLUSIONS

Neutropenia of SGA is a condition of 1-week duration. It is more closely associated with SGA than maternal hypertension (likely owing to neutrophil hypoproduction associated with intrauterine hypoxia), often accompanied by thrombocytopenia, not obviously improved by rG-CSF or IVIG, and associated with an increased risk for NEC.

Affect of Early Life Oxygen Exposure on Proper Lung Development and Response to Respiratory Viral Infections

Children born preterm often exhibit reduced lung function and increased severity of response to respiratory viruses, suggesting that premature birth has compromised proper development of the respiratory epithelium and innate immune defenses. Increasing evidence suggests that premature birth promotes aberrant lung development likely due to the neonatal oxygen transition occurring before pulmonary development has matured. Given that preterm infants are born at a point of time where their immune system is also still developing, early life oxygen exposure may also be disrupting proper development of innate immunity. Here, we review current literature in hopes of stimulating research that enhances understanding of how the oxygen environment at birth influences lung development and host defense. This knowledge may help identify those children at risk for disease and ideally culminate in the development of novel therapies that improve their health.

Is umbilical cord milking always an advantage?

OBJECTIVE

The role of cord milking as an alternative to delayed cord clamping is an area that requires more research. Purpose of this clinical trial was to investigate the impact of umbilical cord milking on the absolute neutrophil counts (ANCs) and the neutropenia frequency of preterm infants.

METHODS

Fifty-eight pregnant women were randomly assigned to one of the umbilical cord milking and control groups. A total of 54 preterm infants (gestational age ≤ 32 weeks) were enrolled into the study. The umbilical cords of 25 infants were clamped immediately after birth, and in 29 infants, umbilical cord milking was performed first.

RESULTS

The ANCs were statistically significantly lower in the cord milking group compared with the control group on days 1, 3 and 7. The frequency of neutropenia was higher in the cord milking group compared with the control group.

CONCLUSION

In our study, ANCs were lower in the cord milking group and the frequency of neutropenia was higher. Umbilical cord milking plays a role on the ANCs of preterm infants.

Evaluation of neutropenia and neutrophilia in preterm infants

OBJECTIVE

Neutrophil counts are used routinely as part of the sepsis evaluation in newborn infants. In this article, we review the normal blood neutrophil concentrations and the clinical approach to neutropenia and neutrophilia in the neonatal period.

METHODS

A literature search was performed using the databases PubMed, EMBASE, and Scopus, and the electronic archive of abstracts presented at the annual meetings of the Pediatric Academic Societies.

RESULTS

Neutropenia and neutrophilia are documented frequently in premature infants. Neutropenia can be seen in up to 8% of all infants admitted to neonatal intensive care. Neutrophilia is even more common, reported in up to 40% of all preterm infants.

CONCLUSIONS

Neutrophil counts should be carefully evaluated in premature neonates. Maternal and perinatal history, physical examination, and a limited laboratory assessment is usually adequate for making a diagnosis in most infants.

Neonatal neutropenia: what diagnostic evaluation is needed and when is treatment recommended?

Neutropenia is a relatively frequent finding in the neonatal intensive care unit, particularly in very low birth weight neonates during the first week of life. Healthy term and preterm neonates have blood neutrophil counts within the same basic range as adults, but their neutrophil function, and their neutrophil kinetics during infection, differ considerably from those of adults. Neutrophil function of neonates, particularly preterm neonates, is less robust than that of adults and might also contribute to the increase in propensity to infection. In premature infants, early-onset neutropenia is correlated with sepsis, maternal hypertension, intrauterine growth restriction, severe asphyxia, and periventricular haemorrhage, and might be associated with an increase in the incidence of early-onset sepsis, nosocomial infection, and Candida colonisation. Some varieties of neutropenia in the NICU are very common and others are extremely rare. The most common causes of neutropenia in the NICU have an underlying cause that is often evident, and require little diagnostic evaluation. Unlike, persistent neutropenia should prompt evaluation even if it is of moderate severity. The laboratory tests to consider are those that provide a specific diagnosis. The first tests that should be ordered are a blood film, a complete blood count on the mother, and, if her blood neutrophil concentration is normal, maternal neutrophil antigen typing and an anti-neutrophil antibody screen. A bone marrow biopsy can be useful in cases with prolonged, unusual, or refractory neutropenia. Various treatments have been proposed as means of enhancing neutrophil production and function in preterm infants. Both recombinant granulocyte stimulating factor and recombinant granulocyte macrophage-colony-stimulating factor have been tried with variable success. Intravenous immunoglobulin, corticosteroids, granulocyte transfusions, and gamma interferon did not show a clear adequate beneficial role for the therapy of neonatal neutropenia.

Eosinophilia in very low birth weight infants

BACKGROUND

Eosinophilia is common in premature infants, though its clinical significance remains unknown. This study investigated the pattern of eosinophilia and related factors in very low birth-weight (VLBW) infants.

METHODS

The medical records of VLBW infants (birth body weight < 1500 g) admitted to the neonatal intensive care unit of a tertiary care center of Cheng Kung University Hospital between January 2005 and June 2007 were analyzed. Complete blood counts (CBC) with differential leukocyte counts were performed weekly. Eosinophilia was defined as an eosinophil count of more than 0.700 x 10(9)/L. The possible related factors were analyzed.

RESULTS

A total of 142 infants were recruited into the study. Those who did not survive after the first 28 days and those with less than four available CBCs were excluded, leaving 107 infants and 828 CBC measurements. Overall, 19.0% of CBCs (157/828) indicated eosinophilia and 69.0% of all infants had at least one instance of eosinophilia during their hospital stay. Eosinophilia mainly occurred in the third week of life (27.1%), with an average peak eosinophil count of 0.520 x 10(9)/L. There were 37.3% of patients with mild eosinophilia (0.700-0.999 x 10(9)/L), 50.7% with moderate eosinophilia (1.000-2.999 x 10(9)/L), and 12% with severe eosinophilia (> or =3.000 x 10(9)/L). The demographic data and perinatal characteristics of infants with and without eosinophilia were comparable. Medical treatments including mechanical ventilation, antibiotic administration, total parenteral nutrition, intravenous catheterization, transfusion, and body weight gains were similar between the two groups. The eosinophil counts in the first week of life were significantly higher in infants with bronchopulmonary dysplasia (p < 0.05). They were also greater in VLBW infants with sepsis at the first, the third, the fourth, the fifth and the seventh weeks (p < 0.05).

CONCLUSION

Eosinophilia is common in VLBW infants and occurs mainly in the third week of life. Higher eosinophil counts were associated with sepsis and family history of atopic eczema. Bronchopulmonary dysplasia was associated with higher eosinophil counts in the first week of life.

Neonatal lupus in triplet pregnancy of a patient with undifferentiated connective tissue disease evolving to systemic lupus erythematosus

Pregnancy in patients suffering from undifferentiated connective tissue disease (UCTD) represents a risk situation for both the mother and the child. SSA/SSB autoantibodies can determine neonatal lupus (NL) in the foetus, regardless of the maternal disease. Furthermore, pregnancy increases the risk of flares and evolution to differentiated connective tissue disease (CTD). We report an uncommon case in which these complications occurred in a mother and in her foetuses. A 37-year-old woman affected by UCTD developed systemic lupus erythematosus (SLE) after her triplet pregnancy. The only manifestation of neonatal lupus we observed in the three newborns was SSA positivity associated with asymptomatic transient neutropenia.

Early neutropenia is not associated with an increased rate of nosocomial infection in very low-birth-weight infants

BACKGROUND

Evidence is contradictory whether very low-birth-weight (VLBW, birth weight <1500 g) infants with early neutropenia (NP), especially those born to mothers with preeclampsia experience a greater incidence of nosocomial infection (NI).

OBJECTIVE

To investigate whether NP within the first 7 days of life is a risk factor for NI in VLBW infants.

METHODS

Over a 42-month period, we identified all VLBW infants born at <or=34 weeks gestation who survived for more than 72 h. Infants who had no evidence of early infection, who had at least one complete blood count performed in the first week of life, and who were not given prophylactic recombinant human granulocyte colony-stimulating factor (rhG-CSF) were included in this retrospective study. Early NP was defined as an absolute neutrophil count less than 1500 per microl at any time during the first week of life. NI was defined as the culture of a bacterial or fungal pathogen from a sterile body fluid that was obtained after 72 h of life in an infant with one or more clinical signs of infection.

RESULTS

A total of 338 VLBW infants were reviewed. Of those, 51 infants were excluded because of death or onset of an infection before 72 h of age, lack of a complete blood count in the first week of life or treatment with rhG-CSF. Of the remaining 287 infants, NI occurred in 11 of 77 (14.3%) infants with early NP compared to 42 of 210 (20.0%) infants without early NP (P=0.31). Infants who developed NI were smaller and less mature, had lower Apgar scores, were more frequently instrumented with central lines and required a longer duration of parenteral nutrition compared to infants without NI. Infants with NI also had a higher mortality and a greater incidence of necrotizing enterocolitis, severe intraventricular hemorrhage and threshold retinopathy of prematurity. However, using stepwise multivariate logistic regression analysis, only the duration of parenteral nutrition and gestational age were significant risk factors for NI.

CONCLUSION

Our data do not support the hypothesis that early NP increases the risk for NI in VLBW infants.

Association of BPD and IVH with early neutrophil and white counts in VLBW neonates with gestational age <32 weeks

OBJECTIVE

To investigate associations between early low neutrophil count from routine blood samples, white blood count (WBC), pregnancy complications and neonatal outcomes for very low birth weight infants (VLBW <or=1500 g) with gestational age <32 weeks.

STUDY DESIGN

Information was abstracted on all infants admitted to level III neonatal intensive care units in Wisconsin 2003 to 2004. A total of 1002 VLBW neonates (78%) had differential and corrected total white counts within 2 (1/2) h of birth. Data analyses included frequency tables, binary logistic, ordinal logistic and ordinary regression.

RESULT

Low neutrophil count (<1000 per microl) was strongly associated with low WBC, pregnancy complications and antenatal steroids. Low neutrophil count predicted bronchopulmonary dysplasia severity level (odds ratio, OR: 1.7, 95% confidence interval, CI: 1.1 to 2.7) and intraventricular hemorrhage grade (OR: 2.2, 95% CI: 1.3 to 3.8).

CONCLUSION

Early neutrophil counts may have multiple causes interfering with their routine use as an inflammatory marker. Nonetheless, low neutrophil count has consistent independent associations with outcomes.

Expected ranges for blood neutrophil concentrations of neonates: the Manroe and Mouzinho charts revisited

BACKGROUND

Upper and lower reference limits for blood neutrophil concentrations of neonates were reported by Manroe, Rosenfeld and co-workers in 1979 and by Mouzinho, Rosenfeld and co-workers in 1994. Studies by Carballo and co-workers and Maynard and co-workers suggested that at high altitude a much higher upper limit of values occurs, and that neutrophilia is often diagnosed inappropriately, at high altitude, if the Manroe and Mouzinho charts are used.

STUDY DESIGN

We revisited the Manroe and Mouzinho charts using modern cell counting instrumentation and very large sample sizes. This was accomplished with data from an 18-hospital health-care system, at hospitals averaging 4,800 feet above sea level. Data were obtained from neonates in the first 10 days following birth, using tests performed on a single type of automated blood cell counter (Beckman Coulter LH 750, Fullerton, CA, USA). To obtain a description of 'expected values,' patients with the following diagnoses, known to have a high proportion of abnormal neutrophil counts, were excluded from the analysis; (1) maternal pregnancy-induced hypertension, (2) early-onset bacterial sepsis, (3) a discharge diagnosis of congenital neutropenia and (4) trisomy 21, 18 or 13.

RESULT

Blood neutrophil concentrations were tabulated from 30 354 tests performed on neonates of 23 to 42 weeks gestation, with dates of birth between 1 January 2004 and 31 May 2007. The reference range charts generated from these data have much higher upper value limits than do the Manroe and Mouzinho charts, and are similar to the high-altitude reports of Carballo and co-workers and Maynard and co-workers. Neonates whose mothers labored before delivery had significantly higher neutrophil counts (averaging 3,500 neutrophils per mul higher, P<0.0001; comparing cesarean section deliveries with vs without labor). Females had significantly higher counts (averaging 2,000 neutrophils per mul higher) than males (P<0.0001). Counts did not differ on the basis of racial/ethnic group.

CONCLUSION

The figures of this report describe the expected ranges for blood neutrophil concentrations over the first 10 days of life among neonates of 23 to 42 weeks gestation at high altitude.

Elevated total peripheral leukocyte count may identify risk for neurological disability in asphyxiated term neonates

OBJECTIVE

The present study investigated the relationship between neurologic outcome and total circulating white blood cell (WBC) and absolute neutrophil counts (ANCs) in the first week of life in term infants with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

Long-term neurologic outcome at 18 months was measured retrospectively in 30 term neonates with HIE using the Pediatric Cerebral Performance Category Scale (PCPCS) score with outcomes dichotomized as either good or poor. We then compared white blood cell and ANC levels during the first 4 days of life and magnetic resonance imaging (MRI) obtained within the first month life between the two PCPCS groups. MRI was quantified using a validated scoring system.

RESULTS

Neonates with good long-term outcomes had significantly lower MRI scores (indicating lesser injury) than neonates with poor outcomes. More importantly, neonates with poor outcomes had significantly higher WBC and ANC levels as early as12 h after birth and up to 96 h after birth compared to those with good outcomes. These data suggest that elevated peripheral neutrophil counts in the first 96 h of life may signal or predict adverse long-term outcome.

CONCLUSIONS

Our findings suggest that elevated peripheral neutrophil counts in the first 96 h of life in term infants with HIE may contribute to abnormal neurodevelopmental outcome.

Low blood neutrophil concentrations among extremely low birth weight neonates: data from a multihospital health-care system

OBJECTIVE

A blood neutrophil concentration < 1000/microl has been reported to occur in about 8% of neonatal intensive care unit (NICU) patients, at some time during their hospital stay. However, the incidence of this finding among extremely low birth weight (ELBW) neonates (< 1000 g birth weight) is not known. Using data from four NICU's in one health-care system, we sought to estimate the incidence, timing, causes, severity and duration of neutrophil counts < 1000/microl among ELBW neonates. We also tabulated the treatments used for this condition and associations with mortality.

METHODS

We performed an historic cohort analysis of all ELBW neonates born during the 36-month period, 1 July 2002 to 30 June 2005, cared for in the four Intermountain Healthcare level III NICU's.

RESULTS

Three hundred and thirty-eight ELBW neonates were the subjects of the analysis. Complete blood cell counts (CBCs) were obtained in all (range, 1 to 123 CBCs/patient). Thirty-eight percent (128/338) had one or more neutrophil counts < 1000/microl. In 57% the low neutrophil count persisted for < 24 h; in 43% it persisted for 1 to 7.5 days. Most of the cases (74%) were detected during the first 3 days of life. Twenty-two percent of cases were not detected until after the first week. Low neutrophil counts were more common among the smallest patients, with a 63% incidence in those < or = 500 g, 44% in those 501 to 600 g and 34% in those 801 to 999 g. When low neutrophil counts were recognized during the first 3 days of life, the patients were typically either small for gestational age (SGA; weight < 10th percentile for gestational age) or born after pregnancy-induced hypertension (PIH) (68%), or had early-onset bacterial infection (6%). When recognized after the first 3 days, the patients typically had necrotizing enterocolitis (31%) or a nosocomial bacterial infection (19%). Alloimmune mechanisms were not tested for in any of the cases. No cause for the low counts was identified among 35% of the neutropenic patients. Intravenous immunoglobulins was administered to 28% of cases, and 100% of these were given according to our written guidelines. Recombinant granulocyte-colony stimulating factor was administered to 13% of cases, and 69% of these were given according to guidelines. Neither the presence of low neutrophil counts nor the severity (lowest recorded count) correlated with mortality rate, except in proven early-onset sepsis.

CONCLUSIONS

We observed low neutrophil counts among ELBW neonates at a rate five times that reported in the general NICU population. Most cases were present in the first days of life and occurred in SGA neonates or those with PIH. In over 1/3, no cause was discovered. We maintain that more consistency is needed in evaluating and treating neutropenia among ELBW neonates.

Indomethacin-associated neutropenia with subsequent Gram-negative sepsis in a preterm infant. Cause or coincidence?

A preterm male infant with a patent ductus arteriosus developed neutropenia during treatment with indomethacin. Afterward, the mother described her own history of indomethacin-associated neutropenia. During the recovery from the neutropenia, the infant became septic with bacteremia caused by Enterobacter cloacae. Although indomethacin-related neutropenia has been described in adults, no case in a neonate has been reported. If neutropenia occurs after indomethacin therapy in a neonate, a familial history of indomethacin-associated neutropenia should be sought and the increased risk of infection should be considered.

Evaluation of eosinophilia in hospitalized preterm infants

OBJECTIVE

To characterize changes in eosinophil counts over time, and to draw comparisons across four gestational age groups with respect to the incidence of, and clinical conditions associated with eosinophilia over the first months of life in a single neonatal intensive care unit (NICU).

STUDY DESIGN

Weekly complete blood counts (CBCs) were collected from all NICU patients. Eosinophilia was classified as mild, moderate, or severe. Changes in eosinophil counts were examined over time, the incidence of eosinophilia was determined by gestational age group, and clinical correlations sought.

RESULTS

Eosinophil data from 1652 CBCs were analyzed from 332 infants. Eosinophilia occurred in 148 infants (45%) during their hospitalization. The prevalence, severity, and timing of eosinophilia varied by gestational age, infection, and red blood cell transfusions.

CONCLUSIONS

The incidence and severity of eosinophilia increased with immaturity, and was temporally associated with infection, necrotizing enterocolitis, and packed red blood cell transfusion.

Patterns of thrombocytosis and thrombocytopenia in hospitalized neonates

OBJECTIVE

We sought to identify changes in platelet (PLT) counts over time, and to evaluate the patterns of thrombocytopenia and thrombocytosis in hospitalized infants 23.8 weeks to term gestation.

STUDY DESIGN

Neonates were divided into four gestational age groups and their PLT counts were retrospectively compared for prevalence of thrombocytopenia, thrombocytosis, and associated conditions.

RESULTS

Postconceptional age, postnatal age, and sepsis (among other factors) affected PLT counts. When counts from noninfected appropriately grown infants were evaluated, the risk of thrombocytopenia and thrombocytosis were highest in the most preterm infants, and these risks changed with corrected gestational age. PLT counts increased weekly over the first 4 weeks of life for all but the most preterm infants.

CONCLUSIONS

These data characterize the incidence of thrombocytopenia and thrombocytosis across a wide range of gestational ages and show that, even in noninfected neonates, these conditions are common, and risk decreases with increasing maturity. The age-related changes in PLT patterns may reflect maturation of platelet regulation.