A trial of recombinant human granulocyte colony stimulating factor for the treatment of very low birthweight infants with presumed sepsis and neutropenia

Adjuvant therapy in neonatal sepsis to prevent mortality - A systematic review and network meta-analysis

BACKGROUND

Despite appropriate antibiotic therapy, the risk of mortality in neonatal sepsis still remains high. We conducted a systematic review to comprehensively evaluate different adjuvant therapies in neonatal sepsis in a network meta-analysis.

METHODS

We included randomized controlled trials (RCTs) and quasi-RCTs that evaluated adjuvant therapies in neonatal sepsis. Neonates of all gestational and postnatal ages, who were diagnosed with sepsis based on blood culture or sepsis screen were included. We searched MEDLINE, CENTRAL, EMBASE and CINAHL until 12th April 2021 and reference lists. Data extraction and risk of bias assessment were performed in duplicate. A network meta-analysis with bayesian random-effects model was used for data synthesis. Certainty of evidence (CoE) was assessed using GRADE.

RESULTS

We included 45 studies involving 6,566 neonates. Moderate CoE showed IVIG [Relative Risk (RR); 95% Credible Interval (CrI): 1.00; (0.67-1.53)] as an adjunctive therapy probably does not reduce all-cause mortality before discharge, compared to standard care. Melatonin [0.12 (0-0.08)] and granulocyte transfusion [0.39 (0.19-0.76)] may reduce mortality before discharge, but CoE is very low. The evidence is also very uncertain regarding other adjunctive therapies to reduce mortality before discharge. Pentoxifylline may decrease the duration of hospital stay [Mean difference; 95% CrI: -7.48 days (-14.50-0.37)], but CoE is very low.

CONCLUSION

Given the biological plausibility for possible efficacy of these adjuvant therapies and that the CoE from the available trials is very low to low except for IVIG, we need large adequately powered RCTs to evaluate these therapies in sepsis in neonates.

Neonatal sepsis: a systematic review of core outcomes from randomised clinical trials

BACKGROUND

The lack of a consensus definition of neonatal sepsis and a core outcome set (COS) proves a substantial impediment to research that influences policy and practice relevant to key stakeholders, patients and parents.

METHODS

A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. In the included studies, the described outcomes were extracted in accordance with the provisions of the Core Outcome Measures in Effectiveness Trials (COMET) handbook and registered.

RESULTS

Among 884 abstracts identified, 90 randomised controlled trials (RCTs) were included in this review. Only 30 manuscripts explicitly stated the primary and/or secondary outcomes. A total of 88 distinct outcomes were recorded across all 90 studies included. These were then assigned to seven different domains in line with the taxonomy for classification proposed by the COMET initiative. The most frequently reported outcome was survival with 74% (n = 67) of the studies reporting an outcome within this domain.

CONCLUSIONS

This systematic review constitutes one of the initial phases in the protocol for developing a COS in neonatal sepsis. The paucity of standardised outcome reporting in neonatal sepsis hinders comparison and synthesis of data. The final phase will involve a Delphi Survey to generate a COS in neonatal sepsis by consensus recommendation.

IMPACT

This systematic review identified a wide variation of outcomes reported among published RCTs on the management of neonatal sepsis. The paucity of standardised outcome reporting hinders comparison and synthesis of data and future meta-analyses with conclusive recommendations on the management of neonatal sepsis are unlikely. The final phase will involve a Delphi Survey to determine a COS by consensus recommendation with input from all relevant stakeholders.

Medicinal Uses of Hematopoietic Growth Factors in Neonatal Medicine

This review focuses on certain hematopoietic growth factors that are used as medications in clinical neonatology. It is important to note at the chapter onset that although all of the pharmacological agents mentioned in this review have been approved by the US Food and Drug administration for use in humans, none have been granted a specific FDA indication for neonates. Thus, in a sense, all of the agents mentioned in this chapter could be considered experimental, when used in neonates. However, a great many of the pharmacological agents utilized routinely in neonatology practice do not have a specific FDA indication for this population of patients. Consequently, many of the agents reviewed in this chapter are considered by some practitioners to be nonexperimental and are used when they judge such use to be "best practice" for the disorders under treatment.The medicinal uses of the agents in this chapter vary considerably, between geographic locations, and sometimes even within an institutions. "Consistent approaches" aimed at using these agents in uniform ways in the practice of neonatology are encouraged. Indeed some healthcare systems, and some individual NICUs, have developed written guidelines for using these agents within the practice group. Some such guidelines are provided in this review. It should be noted that these guidelines, or "consistent approaches," must be viewed as dynamic and changing, requiring adjustment and refinement as additional evidence accrues.

Effects of immunotherapy on mortality in neonates with suspected or proven sepsis: a systematic review and network meta-analysis

Background

To investigate the efficacies of different immunotherapies in neonates with suspected or proven sepsis.

Methods

We searched the Cochrane Library, EMBASE, MEDLINE, EBSCOhost, and Web of Science for studies published before May 2019 that investigated different immunotherapies in neonates with suspected or proven sepsis. Comparisons were among immunotherapies and between immunotherapy and placebo. The review was registered in the PROSPERO CRD database.

Results

All-cause mortality was not significantly different between patients who received the immunoglobulin (IgG), IgM-enriched immunoglobulin (IgGAM), granulocyte-colony stimulating factor (G-CSF) or granulocyte-macrophage colony stimulating factor (GM-CSF) immunotherapies and those who received placebo. The RRs of the immunotherapies were 0.80 (95% CI: 0.57 to 1.1), 0.45 (95% CI: 0.17 to 1.0), 0.93 (95% CI: 0.64 to 1.2) and 0.67 (95% CI: 0.39 to 1.1), respectively. Compared with placebo, none of the interventions showed statistically significant differences in the duration of hospital stay. The MDs of the immunotherapies were − 2.7 (95% CI: − 8.4 to 3.5), − 0.18 (95% CI: − 7.3 to 7.7), − 1.7 (95% CI: − 7.3 to 3.9) and − 7.2 (95% CI: − 28 to 13), respectively.

Conclusions

No significant differences in all-cause mortality or the duration of hospital stay were found in neonates with suspected or proven sepsis treated with the four types of immunotherapies and those treated with placebo.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1609-1) contains supplementary material, which is available to authorized users.

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.

Role of G-CSF GM-CSF in the management of infections in preterm newborns: an update

Neutropenia (definable as an absolute granulocyte count <1,000/μL in neonates) is a relatively frequent condition in small for gestational age and/or low birth weight neonates. Colony stimulating factors (CSF), namely granulocyte- (G-CSF) and granulocyte-macrophage- (GM-CSF) CSF, have been proposed for prophylaxis and therapy of severe infections in this condition. Available data do not support the use of these substances for prophylaxis of infections in the presence of neutropenia. On the contrary, there might be space for their use, mainly for G-CSF, in case of severe infectious complications in severely neutropenic neonates (absolute polymorphonuclear neutrophil count <500/μL) and/or in the presence of specific hematological diseases causing neutropenia.

Neutropenia in the newborn

PURPOSE OF REVIEW

The aim is to review normal blood neutrophil concentrations and the clinical approach to neutropenia in the neonatal period. A literature search on neonatal neutropenia 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.

RECENT FINDINGS

The review summarizes current knowledge on the causes of neutropenia in premature and critically ill neonates, focusing on common causes such as maternal hypertension, neonatal sepsis, twin-twin transfusion, alloimmunization, and hemolytic disease. The article provides a rational approach to diagnosis and treatment of neonatal neutropenia, including current evidence on the role of recombinant hematopoietic growth factors.

SUMMARY

Neutrophil counts should be carefully evaluated in premature and critically ill neonates. Although neutropenia is usually benign and runs a self-limited course in most neonates, it can be prolonged, and it constitutes a serious deficiency in antimicrobial defense in some infants.

The effect of granulocyte colony stimulating factor administration on preterm infant with neutropenia and clinical sepsis: a randomized clinical trial

BACKGROUND

This study was conducted to evaluate the clinical effect of Granulocyte Colony Stimulating Factor (GCSF) on prognosis of neonatal sepsis.

MATERIALS AND METHODS

Present study is a double- blinded randomized clinical trial, conducted on 46 preterm infants with neutropenia (Absolute Neutrophil Count (ANC) ≤ 5000 / μL) and clinical sepsis. Infants were randomly allocated into two groups. In the first group (treatment group), infants were treated with GCSF for up to 5 consecutive days with 10 μg/ kg in addition to standard treatment protocols, and in other group, infants received normal saline as the placebo. Each infant was monitored for 14 days. Primary outcome was mortality during 14 days after entering the study, and secondary outcome was the incidence of positive blood culture, weight gain on the fourteenth day, the duration of hospitalization and medication side effects.

RESULTS

In the treated group, only one death was observed (P-value=1.00). However, no positive results for cultures were reported. Only one case in the treatment group and 3 patients in the control group showed feeding intolerance and needed respiratory support (P-value= 0.608). Length of hospitalization was 25 ± 6 days for the treatment group and 30 ± 7 days for the control group which was statistically significant (P-value=0.042).

CONCLUSION

The results of this study demonstrated that GCSF could reduce the hospital stay, but no significant effect was observed on mortality rate, respiratory or feeding status.

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.

In vivo effect of recombinant human granulocyte colony-stimulating factor on neutrophilic expression of CD11b in septic neonates: a randomized controlled trial

Neonates are susceptible to septicemia secondary to quantitative and qualitative neutrophilic defects. Granulocyte colony-stimulating factor (G-CSF) stimulates myeloid progenitor cell proliferation and induces selective neutrophil functions. The authors aimed to evaluate the effect of G-CSF administration in septic neonates on neutrophil production and CD11b expression. Sixty septic neonates were randomized to receive intravenous G-CSF 10 μg/kg/day for 3 days (G-CSF group, n = 30), or not to receive G-CSF (non-G-CSF group, n = 30). Thirty healthy newborns were included as controls. Laboratory investigations included complete blood count, C-reactive protein, blood culture, renal and liver function tests, and assessment of neutrophilic expression of CD11b. Total leukocytes count (TLC), absolute neutrophil count (ANC), and immature myeloid cell count in G-CSF group showed significant difference between post-and pre-G-CSF levels. TLC, ANC, immature myeloid cell count and immature/total myeloid cells ratio were higher in G-CSF group compared to non-G-CSF group on days 1 and 3. Higher neutrophilic expression of CD11b was reported in both septic groups on day 0 compared to control group. On day 5, CD11b was higher in G-CSF group than non-G-CSF group. G-CSF improved CD11b% in neutropenic and non-neutropenic septic neonates. No significant difference was found between pre- and posttreatment renal and liver function tests. Lower duration of antibiotic intake and hospitalization was observed in G-CSF group compared to non-G-CSF group. G-CSF administration as an adjuvant therapy for neonatal septicemia, whether neutropenic or not, improves neutrophilic count and function and contributed to early healing from sepsis.

A multicenter, randomized, placebo-controlled trial of prophylactic recombinant granulocyte-colony stimulating factor in preterm neonates with neutropenia

OBJECTIVE

To test the hypothesis that prophylactic treatment of neutropenic premature neonates with recombinant granulocyte-colony stimulating factor (rG-CSF) would reduce the incidence of nosocomial infections (NIs).

STUDY DESIGN

A total of 25 neonatal intensive care units participated in this multicenter, randomized, double-blind, placebo-controlled trial. Premature infants of gestational age (GA) <or= 32 weeks were included if they had a peripheral blood count showing < 1500 neutrophils/mm(3) for at least 24 hours during the first 3 weeks of life. A total of 200 infants received either rG-CSF (10 microg/kg/day) or placebo for 3 days. Primary outcome was survival free of infection for 4 weeks after treatment, assessed in an intention-to-treat analysis.

RESULTS

A total of 102 infants received rG-CSF (mean GA, 29.2 weeks), and 98 received placebo (mean GA, 29.1 weeks). Survival free of confirmed infection for 4 weeks after treatment was 74/102 in the rG-CSF group and 66/98 in the placebo group (P = .42). However, during 2 weeks, there was a significant difference between groups (86/102 vs 70/98; P = .028).

CONCLUSIONS

In this population, prophylactic rG-CSF did not significantly increase survival free of infection at 4 weeks after treatment. The transient effect observed at 2 weeks in the most immature infants should be evaluated further.

Intravenous immunoglobulins and haematopoietic growth factors in the prevention and treatment of neonatal sepsis: ground reality or glorified myths?

Neonatal sepsis is a significant cause of morbidity and mortality in the neonatal intensive care unit. The epidemiology of neonatal infections is complex; however, they are in large part secondary to developmentally immature host defence mechanisms. These immunodeficiencies, which are exaggerated in premature and sick neonates, include quantitative and qualitative deficits in phagocytes, complement components, cytokines and immunoglobulins. Therapies that modulate or augment host defences may attenuate the virulence of neonatal infections. In this paper, we have reviewed immunotherapies that modulate the immune system of the neonate, including intravenous immunoglobulins and myeloid haematopoietic growth factors. Future studies should focus on investigating other abnormalities of neonatal host defence and/or combined immunotherapy approaches in an attempt to circumvent the immaturity of host defence and potentially reduce both the incidence and severity of neonatal sepsis.

Reducing the global burden of sepsis in infants and children: a clinical practice research agenda

OBJECTIVE

Sepsis remains a predominant cause of mortality and morbidity in children in the developing and industrialized world. This review discusses a clinical practice research agenda to reduce this global burden.

DESIGN

Summary of the literature with analysis by experts.

RESULTS

Many interventions have been proven effective in decreasing sepsis. Heterologous immunization with attenuated Bacillus Camille Guerin vaccine reduces all-cause mortality, and specific immunizations further reduce morbidity and mortality from many specific microbes. Antepartum antibiotics reduce the prevalence of cerebral palsy and mortality in infants. Administration of antibiotics to neonates with signs of sepsis reduces all-cause mortality five-fold and can also reduce mortality in the big four killers of children: severe pneumonia, diarrhea, malaria, or measles. Immunonutrition with zinc and vitamin A can further reduce morbidity in diarrhea and pneumonia and reduce mortality in measles. First-hour rapid intravenous fluid resuscitation achieves 100% survival in dengue shock, and time-sensitive fluid resuscitation and inotropic support reduces mortality ten-fold in meningococcal septic shock. Multiple organ failure occurs when late or inadequate resuscitation results in systemic thrombosis or when infection is not eradicated because of immunosuppression or inadequate source control.

CONCLUSIONS

The global burden of sepsis can be reduced by 1) prevention with improved heterologous or specific vaccines and vitamin or mineral supplement programs; 2) early recognition and treatment with appropriate antibiotics, intravenous fluid resuscitation, and inotropic support in organized healthcare-delivery systems; and 3) development of new diagnostics and therapeutics that reduce systemic thrombosis, improve immune function, and kill resistant organisms.

Sepsis associated with immunosuppressive medications: an evidence-based review

OBJECTIVE

In 2003, critical care and infectious disease experts representing 11 international organizations developed management guidelines for sepsis associated with immunosuppressive medications that would be of practical use for the bedside clinician, under the auspices of the Surviving Sepsis Campaign, an international effort to increase awareness and improve outcome in severe sepsis.

DESIGN

The process included a modified Delphi method, a consensus conference, several subsequent smaller meetings of subgroups and key individuals, teleconferences, and electronic-based discussion among subgroups and among the entire committee.

METHODS

The modified Delphi methodology used for grading recommendations built on a 2001 publication sponsored by the International Sepsis Forum. We undertook a systematic review of the literature graded along five levels to create recommendation grades from A to E, with A being the highest grade. Pediatric considerations to contrast adult and pediatric management are in the article by Parker et al. on p. S591.

CONCLUSION

Immunosuppressed patients, by definition, are susceptible to a wider spectrum of infectious agents than immunologically normal patients and, thus, require a broader spectrum antimicrobial regimen when they present with sepsis or septic shock. Special expertise managing immunosuppressed patient populations is needed to predict and establish the correct diagnosis and to choose appropriate empiric and specific agents and maximize the likelihood that patients will survive these microbial challenges.

Effect of granulocyte colony-stimulating factor in experimental methicillin resistant Staphylococcus aureus sepsis

Background

Methicillin resistant Staphylococcus aureus (MRSA) is the leading pathogenic cause of nosocomial infections, especially in bacteraemia and sepsis. The essential therapy for MRSA infection is glycopeptides. Therapeutic failure can be seen with this therapy and the mortality is still high. The aim of this study was to evaluate the additional effect of G-CSF on the traditional antibiotic treatment in an experimental MRSA sepsis.

Methods

Experimental sepsis was performed in mice by intraperitoneal injection of MRSA isolate. Inoculum dose was estimated as 6 × 10⁹/ml. Mice were randomised for the study into four group; control group (not receive any therapy), G-CSF group (1000 ng/daily, subcutaneously for 3 d), antibiotic group (vancomycin 25 or 50 mg/kg intraperitoneally every 12 hours for 7 d), and vancomycin+G-CSF group (at the same concentrations and duration). Autopsy was done within one hour after mice died. If mice was still alive at the end of seventh day, they were sacrificed, and autopsy was done. In all groups, the effect of G-CSF therapy on the survival, the number of the MRSA colonies in the lung, liver, heart, spleen, and peritoneal cultures, the histopathology of the lung, liver, heart and spleen was investigated.

Results

One hundred and six mice were used. There were no significant differences in survival rates and bacterial eradication in G-CSF group compared with control group, and also in antibiotic +G-CSF group compared with antibiotic alone group. These parameters were all significantly different in antibiotic alone group compared with control group. Histopathologically, inflammation of the lung and liver were significantly reduced in vancomycin (25 mg/kg)+G-CSF and vancomycin (50 mg/kg)+G-CSF subgroups, respectively (p < 0.01). The histopathological inflammation of the other organs was not significantly different in antibiotic+G-CSF group compared with antibiotic group and, also G-CSF group compared with control group.

Conclusion

G-CSF treatment had no additional effect on survival and bacterial eradication in MRSA sepsis in nonneutropenic mice; and only a little effect on histopathology. G-CSF treatment is very expensive, likewise glycopeptides. The more interest in infection control measures, and prevent the spread of MRSA infections is more rational.

Effects of enterally administering granulocyte colony-stimulating factor to suckling mice

Gastrointestinal (GI) tract development is influenced by multiple growth factors, some of which are delivered directly to the GI lumen, as they are swallowed constituents of amniotic fluid, colostrum, and milk. Granulocyte colony-stimulating factor (G-CSF), traditionally known as a granulocytopoietic growth factor, is an example of one such factor. However, it is not clear whether the large amounts of G-CSF that are normally swallowed by the fetus and neonate have systemic effects on circulating neutrophils or local effects in the developing intestine. To assess this, we administered either active or heat-denatured (control) recombinant human G-CSF to 5- to 7-d-old C57BL/6 x 129SvJ mice. Pups received either a low dose (3 ng) that was calculated to approximate the amount of G-CSF swallowed in utero from amniotic fluid or an isovolemic high dose 100 times larger (300 ng). Oral dosing was performed daily for either 3 or 7 d, after which pups were killed and measurements were made on the blood and the GI tract. Absolute blood neutrophil counts and immature to total neutrophil ratios did not differ from controls in any of the test groups. However, intestinal villus area, perimeter, length, crypt depth, and proliferating cell nuclear antigen index increased significantly among those that were treated with active G-CSF. Thus, in suckling mice, enterally administered G-CSF had no effect on the concentration of circulating neutrophils but had trophic effects on the intestine. We speculate that the G-CSF present in amniotic fluid, colostrum, and milk acts as a topical intestinal growth factor and has little or no granulocytopoietic action.

Neonatal transfusion practice

Many previously widely accepted neonatal transfusion practices are changing as neonatologists become more aware of the risks to their patients of multiple blood product transfusions. Recent literature and research on neonatal transfusion practice are here reviewed, and practical guidelines and trigger thresholds for blood products commonly used in neonatal medicine are proposed.

Haemopoietic growth factors for neonates: assessing risks and benefits

This review summarises the rationale, clinical trial evidence for benefit and potential toxicities of Erythropoietin, Thrombopoietin, Granulocyte Colony Stimulating Factor and Granulocyte-Macrophage Colony Stimulating Factor. Erythropoietin has failed to have a clinical impact on red cell transfusion requirement in very low birth weight infants; it is uncertain whether Thrombopoietin will find a significant clinical role in neonatal thrombocytopenia and there is, as yet, insufficient evidence for the routine use of Granulocyte- or Granulocyte-Macrophage Colony Stimulating Factor to prevent or treat bacterial infection. A number of theoretical risks of haemopoietic growth factor use in neonates have been suggested, but no toxicities have been observed during their clinical use. Exploring the potential for benefit in selected groups of infants should be encouraged.

Immunotherapy in the prophylaxis and treatment of neonatal sepsis

Neonatal sepsis is a significant cause of morbidity and mortality in the neonatal intensive care unit. The epidemiology of neonatal infections is complex; however, they are in large part secondary to developmentally immature host defense mechanisms. These immunodeficiencies, which are exaggerated in premature and sick neonates, include quantitative and qualitative deficits in phagocytes, complement components, cytokines, and immunoglobulins. Therapies that modulate or augment host defenses may attenuate the virulence of neonatal infections. In this paper, we have reviewed immunotherapies that modulate the immune system of the neonate, including: intravenous immunoglobulins, myeloid hematopoietic growth factors, and granulocyte transfusions. Future studies should focus on investigating other abnormalities of neonatal host defense and/or combined immunotherapy approaches in an attempt to circumvent the immaturity of host defense and potentially reduce both the incidence and severity of neonatal sepsis.

Randomized, double-blinded, placebo-controlled trial of early administration of recombinant human granulocyte colony-stimulating factor to non-neutropenic preterm newborns between 33 and 36 weeks with presumed sepsis

A randomized, double-blinded, placebo-controlled trial was conducted of early administration of recombinant granulocyte colony-stimulating factor (rGCSF) to 40 non-neutropenic, preterm infants between 33 and 36 weeks of gestational age with the diagnosis of presumed sepsis. The treatment group (n = 20) received 5 microg/kg per day of intravenous rGCSF once daily for 3 d and the control group (n = 20) received the same volume of physiological serum. Immediately before the first dose and on the 4th day, plasma levels of GCSF and tumour necrosis factor-alpha (TNF-alpha), absolute neutrophil counts (ANC), immature neutrophil count (INC), immature/total neutrophil (I/T) ratios and platelet counts were determined. At study entry, the plasma GCSF and TNF-alpha levels were similar. On day 4, there was no significant change in GCSF levels in either groups, whereas there was a significant decrease in TNF-alpha levels in the treatment group. ANC and INC of the treatment group also increased significantly. The I/T ratio continued at the same level in the treatment group, but decreased significantly on days 4 and 7 day in the control group. The length of time on the neonatal intensive care unit (NICU) was significantly shorter in the treatment group. In conclusion, early administration of 3 daily doses of rGCSF (5 microg/kg per day) to non-neutropenic, preterm infants who had presumed sepsis increased circulating ANC and INC, decreased plasma TNF-alpha levels and shortened the length of time on the NICU.

What is the rationale for the use of granulocyte and granulocyte-macrophage colony-stimulating factors in the neonatal intensive care unit?

Neonatal sepsis remains an unsolved major contributor to morbidity and mortality. In the 1980s the promise of augmenting immune function using pooled intravenous gammaglobulin to supplement the exceedingly low levels of immunoglobulin G in premature infants failed to demonstrate a clear advantage. Similarly, cytokine augmentation of cellular function in the 1990s largely appeared to be suffering the same fate. However, both results may arise from a problem in experimental design where the combination of both treatments may be necessary along with specific antibody. For example, in vitro, independently of an array of other humoral and cellular immature immune system issues, opsonization of bacteria is improved in the presence of antibody. The question is whether the same result can be achieved in vivo. No experiments have been reported that directly test this hypothesis.

CONCLUSION

More investigation is needed in this challenging area of neonatal research.

How to leverage an endogenous immune defense mechanism: the example of granulocyte colony-stimulating factor

Our understanding of host defense has exploded during the past two decades. It is temping to take advantage of this knowledge by considering the modulation and control of these mechanisms as therapeutic options. In intensive care medicine, the aim is usually to block an overwhelming inflammatory response, which represents the "bad" side of the double-edged sword of host defense. The obvious danger of such treatment strategies is that impairing the inflammatory reaction means impairing host defense in patients exposed to infectious agents. The alternative approach, i.e., strengthening or supplementing favorable host defense mechanism, has so far been little explored clinically. Granulocyte colony-stimulating factor, the granulocyte colony-stimulating factor, combines the unique properties of an anti-infectious and an anti-inflammatory factor. This attractive profile has led us to various approaches to exploit these immunomodulatory activities. In a recently terminated, placebo-controlled, randomized study, we investigated if prophylactic treatment with rh granulocyte colony-stimulating factor (Filgrastim), at the time a risk can be anticipated such as before an operation, may offer protection from immunoinflammatory dyshomeostasis and thus lower the incidence of postoperative sepsis. Perioperative rh granulocyte colony-stimulating factor administration, compared with placebo treatment, resulted in the prevention of postoperative monocyte deactivation, conservation of an adequate Th1/Th2 ratio, as well as a considerable alleviation of the acute phase response. In parallel, there was a clear tendency toward lowering the rate of postoperative septic complications under the administration of Filgrastim.

G-CSF and GM-CSF for treating or preventing neonatal infections

BACKGROUND

The colony stimulating factors (CSFs), granulocyte-macrophage colony stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF), are naturally occurring cytokines that stimulate the production and antibacterial function of neutrophils and monocytes. Two strategies have been adopted for exploring whether CSFs can provide clinical benefit for preterm infants. The first has investigated their use as a treatment to improve outcome in established systemic infection, especially when complicated by a low neutrophil count. The alternative strategy has been to use CSFs prophylactically, to prevent sepsis prospectively through stimulation of neutrophil production and bactericidal function.

OBJECTIVES

To determine the efficacy and safety of the haemopoietic colony stimulating factors (G-CSF or GM-CSF) in newborn infants, when used for:a) treatment of suspected or proven systemic infection to reduce mortality, orb) prophylaxis, to prevent systemic infection in infants at high risk of nosocomial infection. To determine, in subgroup analysis, the influence of pre-existing or high risk of neutropenia on the outcome of therapy.

SEARCH STRATEGY

PubMed, EMBASE, MEDLINE and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2003) were searched in April 2003 using the keywords: G-CSF, GM-CSF, infant newborn, with and without the limit Clinical Trial. In addition, reference lists of identified RCTs, meta-analyses and personal files were searched.

SELECTION CRITERIA

The criteria used to select studies for inclusion were:

DESIGN

RCT.

SUBJECTS

Newborn infants in intensive care.

INTERVENTIONS

G-CSF or GM-CSF given as treatment in conjunction with antibiotics for suspected or microbiologically proven systemic infection. G-CSF or GM-CSF given as prophylaxis with the aim of reducing the incidence of systemic infection.

OUTCOMES

Treatment studies reporting all cause mortality. Prophylaxis studies reporting subsequent incidence of sepsis and / or mortality.

DATA COLLECTION AND ANALYSIS

Relative risks (RR) and risk differences (RD) with 95% confidence intervals (CI) using the fixed effect model are reported. Number needed to treat (NNT) was calculated for the outcomes that showed a statistically significant reduction in RR.

MAIN RESULTS

Seven treatment studies of 257 infants with suspected systemic bacterial infection and three prophylaxis studies comprising 359 neonates are analysed. Treatment studies: There is no evidence that the addition of G-CSF or GM-CSF to antibiotic therapy in preterm infants with suspected systemic infection reduces immediate all cause mortality. No significant survival advantage was seen at 14 days from the start of therapy [typical RR 0.71 (95% CI 0.38,1.33); typical RD -0.05 (95% CI -0.14, 0.04)]. However all seven of the treatment studies were small, the largest recruiting only 60 infants. The subgroup analysis of 97 infants from three treatment studies who, in addition to systemic infection, had clinically significant neutropenia (< 1.7 x 10(9)/l) at trial entry, does show a significant reduction in mortality by day 14 [RR 0.34 (95% CI 0.12, 0.92); RD -0.18 (95% CI -0.33, -0.03); NNT 6 (95% CI 3-33)]. Prophylaxis studies have not demonstrated a significant reduction in mortality in neonates receiving GM-CSF [RR 0.59 (95% CI 0.24,1.44); RD -0.03 (95% CI -0.08,0.02)]. The identification of sepsis as the primary outcome of prophylaxis studies has been hampered by inadequately stringent definitions of systemic infection. However, data from one study suggest that prophylactic GM-CSF may provide protection against infection when given to preterm infants who are neutropenic or at high risk of developing postnatal neutropenia.

REVIEWER'S CONCLUSIONS

There is currently insufficient evidence to support the introduction of either G-CSF or GM-CSF into neonatal practice, either as treatment of established systemic infection to reduce resulting mortality, or as prophylaxis to prevent systemic infection in high risk neonates. No toxicity of CSF use was reported in any systemic infection to reduce resulting mortality, or as prophylaxis to prevent systemic infection in high risk neonates. No toxicity of CSF use was reported in any study included in this review. The limited data suggesting that CSF treatment may reduce mortality when systemic infection is accompanied by severe neutropenia should be investigated further in adequately powered trials which recruit sufficient infants infected with organisms associated with a significant mortality risk.

A practical approach to neutrophil disorders

This review discusses disorders of altered neutrophil number and function and provide a basic framework for patient evaluation and management. The sections begin with neutropenia, neutrophilia and neutrophil dysfunction with a general screening approach to differentiate common, more benign syndromes from rare, often more serious disorders. Also included is a detailed discussion of some specific primary neutrophil syndromes at the end of each section. Focus is placed on specific disorders that are clinically common or particularly instructive.

In vivo effect of rhGM-CSF And rhG-CSF on monocyte HLA-DR expression of septic neonates

OBJECTIVE

To investigate the effect of rhGM-CSF and rhG-CSF on the monocyte HLA-DR expression of septic neonates.

SUBJECTS

60 septic neonates and 41 healthy ones. Septic neonates were randomly assigned into three treatment groups, the GM-CSF group [n=20, rhGM-CSF 5 mcg/kg/d for 4 days, intravenously over 2h (IV)], the G-CSF group (n=20, rhG-CSF 10 mcg/kg/d for 4 days, IV) and the placebo group (n=20, normal saline for 4 days, IV).

MEASUREMENTS

Serial (days 0,1, 3 and 5 after the onset of sepsis) measurements of the percentage of HLA-DR positive monocytes (%HLA-DR+ monocytes) and mean fluorescence intensity (MFI) by flow-cytometry as well as the absolute monocyte counts (AMC).

MAIN RESULTS

On day 0, the HLA-DR expression of the septic neonates (%HLA-DR+ monocytes: 38%+/-1.8% (mean+/-SEM) and MFI: 73+/-3.4) was significantly lower than the healthy control values (%HLA-DR+ monocytes: 68%+/-2% and MFI: 123+/-4.6) (P<0.0001, for both parameters). On follow up (days 1, 3 and 5), a significant increase of HLA-DR expression was observed in all the groups of septic neonates. Healthy control values of %HLA-DR+ monocytes were reached by day 1 in the GM-CSF group and by day 3 in the G-CSF and placebo groups. Healthy control values of MFI were reached by day 3 in all groups of septic neonates. The AMC showed a significant increase in the GM-CSF group (during the whole follow up period) and in the G-CSF group (for the first 3 days of follow up).

CONCLUSIONS

The monocyte HLA-DR expression is depressed on the onset of neonatal sepsis and is progressively restored during the following days. Treatment with rhGM-CSF results in an earlier increase of the number of monocytes expressing the HLA-DR.

Use of myeloid colony-stimulating factors in neonates with septicemia

Bacterial sepsis is a major cause of neonatal morbidity and mortality. Successful management of neonatal sepsis requires early diagnosis, appropriate antimicrobial treatment, and aggressive intensive care. However, even when steps are taken appropriately, mortality rates can be high, particularly among certain subgroups, such as extremely preterm neonates and neonates with neutropenia. Multiple factors contribute to the increased susceptibility of neonates to infection, including developmental quantitative and qualitative neutrophil defects. Studies of infected animal and human neonates suggest that the use of recombinant human granulocyte colony stimulating factor (rhG-CSF) or recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) can partially counterbalance these defects and thereby reduce morbidity and mortality. However, the body of clinical evidence is currently not sufficient to recommend rhG-CSF or rhGM-CSF administration confidently as routine adjunctive treatment for neonates with sepsis.