Low plasma protein C values predict mortality in low birth weight neonates with septicemia

A Global Assessment of Coagulation Profile and a Novel Insight into Adamts-13 Implication in Neonatal Sepsis

Neonatal sepsis is a life-threatening condition associated with significant morbidity and mortality. Sepsis-induced coagulopathy is a well-recognized entity, signifying the strong cross-talk between inflammation and coagulation. The aim of the present study was to compare the coagulation profile between the acute phase of sepsis and recovery in term and preterm neonates. Additional comparisons to healthy neonates were undertaken. Levels of clotting, anti-clotting factors and ADAMTS-13 (A disintegrin and metalloprotease with thrombospondin type-1 motives), the cleaving protein of von Willebrand factor (VWF), were measured in 16 term and preterm neonates in the acute phase of infection and following recovery, as well as in 18 healthy neonates. Clotting times were prolonged, while levels of particular clotting factors were lower in the acute phase of infection compared to controls and recovery. On the other hand, levels of fibrinogen, factor VIII (FVIII) and VWF were significantly higher in the acute phase in comparison to controls and recovery, while they remained persistently higher in the infection group compared to controls. In regard to the anticlotting mechanism, a clear suppression was observed in septic neonates. ADAMTS-13 levels were significantly lower in the acute phase of infection in comparison to controls and recovery (p = 0.015 and 0.004, respectively), while a trend toward superimposed normalization was demonstrated post infection, as higher ADAMTS-13 levels were measured in recovered neonates compared to controls (p = 0.002). The coagulation profile is considerably deranged in neonatal sepsis. ADAMTS-13 deficiency in septic neonates is a novel finding with promising future implications, as ADAMTS-13 substitution may serve as a useful therapeutic option in neonatal sepsis, prompting further investigation in future studies.

Change in Score for Neonatal Acute Physiology-II Measurements for Prediction of Mortality in Severely Septic Preterm Neonates

OBJECTIVE

To study the discriminatory ability of the change (delta) in the Score for Neonatal Acute Physiology-II (SNAP-II) for 14-d mortality in preterm neonates with severe sepsis.

METHODS

Consecutively born neonates of < 34-wk gestation during the 1-y study period in a tertiary care neonatal unit were included. SNAP-II was recorded at the onset of severe sepsis (T0) and serially at 24 (T1), 48 (T2), and 72 (T3) h. Delta scores (Δ SNAP-II) were derived from the difference between the SNAP-II at baseline and each one of the subsequent time points.

RESULTS

Seventy-one preterm neonates were enrolled. Baseline characteristics were similar in survivors (n = 53) and nonsurvivors (n = 18). Median SNAP-II at all the four time points were significantly higher in nonsurvivors (p < 0.001). Delta SNAP-II (T0-T2) was significantly different between nonsurvivors and survivors (mean difference: -14.7; 95% CI: -29, -0.9; p = 0.02), while the difference was not significant between T0-T1 and T0-T3. Initial SNAP-II had a significantly better discriminating ability than Δ SNAP-II at various time points (AUC, 95% CI: 0.59, 0.41-0.75 for T0-T1; 0.70, 0.50-0.87 for T0-T2; and 0.64; 0.38-0.89 for T0-T3).

CONCLUSIONS

Delta SNAP-II does not have a better discriminatory ability for mortality by 14 d in preterm neonates with severe sepsis.

Protein C Pathway in Paediatric and Neonatal Sepsis

Protein C plays a major role in the physiological regulation of coagulation pathways through inactivation of factor Va, factor VIIIa, and plasminogen activator inhibitor. Protein C is involved in the control of inflammation during sepsis, by inhibiting release of pro-inflammatory cytokines, thereby controlling neutrophil, and monocyte effects on injured tissue. Recombinant human activated protein C (rhAPC) reduced mortality in adult sepsis in earlier studies but had no significant benefit in more recent trials. Protein C levels are reduced during paediatric and neonatal sepsis, which may play a major role in the development of disseminated intravascular thrombosis, purpura fulminans, and multiorgan dysfunction. The role of protein C in paediatric sepsis requires further clinical and immunological evaluation to define the patient subgroups who may benefit from this therapy. Newer versions of rhAPC are under development with less risk of haemorrhage potentially broadening the scope of this intervention.

Predictors of death in infants with probable serious bacterial infection

BackgroundBacterial infections account for a significant proportion of neonatal and infant mortality globally. We aimed to identify predictors of death in infants with probable serious bacterial infection (PSBI) defined as signs/symptoms of possible serious bacterial infection along with baseline C-reactive protein (CRP) ≥12 mg/l.MethodsWe did a secondary analysis using the data collected from 700 infants with PSBI who participated in a randomized controlled trial in India in which zinc or placebo was given in addition to the standard antibiotics. Logistic regression was used to estimate the associations between relevant variables and death within 21 days.ResultsThose infants who were fed cow's milk or formula before the illness episode had 3.7-fold (95% confidence interval (CI) 1.5-9.3) and 5.3-fold (95% CI 2.0-13.6) higher odds of death, respectively. Lethargy (odds ratio (OR) 2.4, 95% CI 1.1-5.4) and CRP (OR 1.9, 95% CI 1.1-3.3) were also independent predictors of death. In the model including only clinical features, female gender (OR 2.25, 95% CI 1.0-5.0), abdominal distention (3.7, 95% CI 1.1-12.3), and bulging fontanelle (5.8, 95% CI 1.1-30.5) were also independent predictors for death.ConclusionFormula or cow milk feeding prior to the illness, lethargy at the time of presentation, and high serum CRP levels predicted death in infants with PSBI.

Nonactivated Protein C in the Treatment of Neonatal Sepsis: A Retrospective Analysis of Outcome

BACKGROUND

Previously, we found that plasma protein C (PC) activity ≤10% significantly increased the probability of the occurrence of death during neonatal sepsis. Accordingly, if the activity of plasma PC declined during the course of sepsis to ≤10%, we administered a nonactivated PC zymogen to increase a PC activity. The aim of that retrospective analysis was to explore treatment effects of PC zymogen supplementation in septic infants, with plasma PC activity ≤10%.

METHODS

A database was used to locate 85 newborns treated with PC from among 458 analyzed infants with confirmed sepsis.

RESULTS

The median birth weight and gestational age of treated infants were, respectively, 1010.0 g and 29 weeks. In 47 infants, early-onset sepsis developed, whereas in 38 neonates, late-onset sepsis was recognized. PC was given as a single dose of 200 IU/kg. Among 458 septic patients, death occurred in 19 newborns (4.2%), exclusively in infants with plasma PC activity ≤10%. In 15 infants, death occurred in the course of early-onset sepsis and 4 newborns died of late-onset sepsis (early-onset sepsis vs. late-onset sepsis; P = 0.036; χ with the Yates correction).

CONCLUSIONS

An increased risk of death in septic neonates with plasma PC activity ≤10% suggests the necessity for its evaluation and possibility of supplementation of PC zymogen.

Use and Future Investigations of Recombinant and Plasma-Derived Coagulation and Anticoagulant Products in the Neonate

Although congenital bleeding disorders can manifest in the newborn period, the most common causes of bleeding and thrombosis in neonates are acquired conditions. Factor concentrates are used for specific diagnoses (hemophilia with inhibitors, specific factor deficiency, von Willebrand disease) and approved indications, and increasingly for off-label indications (bleeding in surgery cardiopulmonary bypass, extracorporeal membrane oxygenation). We will review the approved indications for factor products in the neonate and discuss the evidence and rationale for off-label use of factor products in management of bleeding and thrombosis in the neonate.

Predictors of time to recovery in infants with probable serious bacterial infection

INTRODUCTION

Serious bacterial infections continue to be an important cause of death and illness among infants in developing countries. Time to recovery could be considered a surrogate marker of severity of the infection. We therefore aimed to identify clinical and laboratory predictors of time to recovery in infants with probable serious bacterial infection (PSBI).

METHODS

We used the dataset of 700 infants (7-120 days) enrolled in a randomised controlled trial in India in which 10mg of oral zinc or placebo was given to infants with PSBI. PSBI was defined as signs/symptoms of possible serious bacterial infection along with baseline C-reactive protein(CRP) level >12mg/L. Time to recovery was defined as time from enrolment to the end of a 2-day period with no symptoms/signs of PSBI and daily weight gain of at least 10g over 2 succesive days on exclusive oral feeding. Cox proportional hazard regression was used to measure the associations between relevant variables and time to recovery.

RESULTS

Infants who were formula fed prior to illness episode had 33% longer time to recovery (HR-0.67, 95%CI-0.52, 0.87) than those who were not. Being underweight (HR-0.84, 95%CI-0.70, 0.99), lethargic (HR-0.77, 95%CI-0.62, 0.96) and irritable (HR-0.81, 95%CI-0.66, 0.99) were independent predictors of time to recovery. Baseline CRP was significantly associated with time to recovery (P<0.001), higher CRP was associated with longer time to recovery and this association was nearly linear.

CONCLUSION

Simple clinical and laboratory parameters such as formula feeding prior to the illness, being underweight, lethargic, irritable and having elevated CRP levels could be used for early identification of infants with PSBI at risk for protracted illness and could guide prompt referral to higher centers in resource limited settings. This also provides prognostic information to clinicians and family as longer recovery time has economic and social implications on the family in our setting.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00347386.

Activated protein C improves pial microcirculation in experimental endotoxemia in rats

INTRODUCTION

The brain is one of the first organs affected clinically in sepsis. Microcirculatory alterations are suggested to be a critical component in the pathophysiology of sepsis. The aim of this study was to investigate the effects of recombinant human activated protein C (rhAPC) on the pial microcirculation in experimental endotoxemia using intravital microscopy. Our hypothesis is rhAPC protects pial microcirculation in endotoxemia.

METHODS

Endotoxemia was generated in Lewis rats with intravenous injection of lipopolysaccharide (LPS, 5 mg/kg i.v.). Dura mater was removed through a cranial window to expose pial vessels on the brain surface. The microcirculation, including leukocyte-endothelial interaction, functional capillary density (FCD) and plasma extravasation of pial vessels was examined by fluorescent intravital microscopy (IVM) 2 h after administration of LPS, LPS and rhAPC or equivalent amount of saline (used as Control group). Plasma cytokine levels of interleukin 1 alpha (IL1-α), tumor necrosis factor-α (TNF-α), interferon γ (IFN-γ), Monocyte chemotactic protein-1 (MCP-1) and Granulocyte-macrophage colony-stimulating factor (GM-CSF) were evaluated after IVM.

RESULTS

LPS challenge significantly increased leukocyte adhesion (773±190 vs. 592±152 n/mm(2) Control), decreased FCD (218±54 vs. 418±74 cm/cm(2) Control) and increased proinflammatory cytokine levels (IL-1α: 5032±1502 vs. 8±21 pg/ml; TNF-α: 1823±1007 vs. 168±228 pg/ml; IFN-γ: 785±434 vs. 0 pg/ml; GM-CSF: 54±52 vs. 1±3 pg/ml) compared to control animals. rhAPC treatment significantly reduced leukocyte adhesion (599±111 n/mm(2)), increased FCD (516±118 cm/cm(2)) and reduced IL-1α levels (2134±937 pg/ml) in the endotoxemic rats.

CONCLUSION

APC treatment significantly improves pial microcirculation by reducing leukocyte adhesion and increasing FCD.

Pathophysiology and treatment of septic shock in neonates

Neonatal septic shock is a devastating condition associated with high morbidity and mortality. Definitions for the sepsis continuum and treatment algorithms specific for premature neonates are needed to improve studies of septic shock and assess benefit from clinical interventions. Unique features of the immature immune system and pathophysiologic responses to sepsis, particularly those of extremely preterm infants, necessitate that clinical trials consider them as a separate group. Keen clinical suspicion and knowledge of risk factors will help to identify those neonates at greatest risk for development of septic shock. Genomic and proteomic approaches, particularly those that use very small sample volumes, will increase our understanding of the pathophysiology and direct the development of novel agents for prevention and treatment of severe sepsis and shock in the neonate. Although at present antimicrobial therapy and supportive care remain the foundation of treatment, in the future immunomodulatory agents are likely to improve outcomes for this vulnerable population.

Role of innate host defenses in susceptibility to early-onset neonatal sepsis

Neonatal sepsis continues to take a devastating toll globally. Although adequate to protect against invasive infection in most newborns, the distinct function of neonatal innate host defense coupled with impairments in adaptive immune responses increases the likelihood of acquiring infection early in life, with subsequent rapid dissemination and death. Unique differences exist between neonates and older populations with respect to the capacity, quantity, and quality of innate host responses to pathogens. Recent characterization of the age-dependent maturation of neonatal innate immune function has identified novel translational approaches that may lead to improved diagnostic, prophylactic, and therapeutic modalities.

Human protein C concentrate in the treatment of purpura fulminans: a retrospective analysis of safety and outcome in 94 pediatric patients

INTRODUCTION

Purpura fulminans (PF) is a devastating complication of uncontrolled systemic inflammation, associated with high incidence of amputations, skin grafts and death. In this study, we aimed to clarify the clinical profile of pediatric patients with PF who improved with protein C (PC) treatment, explore treatment effects and safety, and to refine the prognostic significance of protein C plasma levels.

METHODS

In Germany, patients receiving protein C concentrate (Ceprotin, Baxter AG, Vienna, Austria) are registered. The database was used to locate all pediatric patients with PF treated with PC from 2002 to 2005 for this national, retrospective, multi-centered study.

RESULTS

Complete datasets were acquired in 94 patients, treated in 46 centers with human, non-activated protein C concentrate for purpura fulminans. PC was given for 2 days (median, range 1-24 days) with a median daily dose of 100 IU/kg. Plasma protein C levels increased from a median of 27% to a median of 71% under treatment. 22.3% of patients died, 77.7% survived to discharge. Skin grafts were required in 9.6%, amputations in 5.3%. PF recovered or improved in 79.8%, remained unchanged in 13.8% and deteriorated in 6.4%. Four adverse events occurred in 3 patients, none classified as severe. Non-survivors had lower protein C plasma levels (P < 0.05) and higher prevalence of coagulopathy at admission (P < 0.01). Time between admission and start of PC substitution was longer in patients who died compared to survivors (P = 0.03).

CONCLUSIONS

This retrospective dataset shows that, compared to historic controls, only few pediatric patients with PF under PC substitution needed dermatoplasty and/or amputations. Apart from epistaxis, no bleeding was observed. Although the data comes from a retrospective study, the evidence we present suggests that PC had a beneficial impact on the need for dermatoplasty and amputations, pointing to the potential value of carrying out a prospective randomised controlled trial.

Protein C preserves microcirculation in a model of neonatal septic shock

OBJECTIVES

Sepsis remains a disease with a high mortality in neonates. Microcirculatory impairment plays a pivotal role in the development of multiorgan failure in septic newborns. The hemodynamic effects of recombinant activated protein C (rhAPC) were tested in an animal model of neonatal septic shock focusing on intestinal microcirculation.

MATERIALS AND METHODS

Endotoxic shock was triggered by intravenous application of Escherichia coli lipopolysaccarides in newborn piglets. Thereafter, five animals received a continuous infusion of 24 microg/kg/h rhAPC, and five received vehicle for control. Over the course of three hours, intestinal microcirculation was assessed by intravital microscopy every 30 min. Macrocirculation and blood counts were monitored simultaneously.

RESULTS

After a short hypotensive period in all animals, the arterial blood pressure returned to baseline in the rhAPC-treated piglets, whereas the hypotension became increasingly severe in the controls. By 90 min, mean blood pressure in the controls was significantly lower than in the treatment group. Similar observations were made regaring microcirculation. After an early impairment in all study animals, functional capillary density and intestinal microcirculatory red blood cell velocity and red blood cell flow recovered in the rhAPC group, but deteriorated further in the control piglets.

CONCLUSION

Recombinant activated protein C protects macro- and microcirculation from endotoxic shock.

Fulminant sepsis/meningitis due to Haemophilus influenzae in a protein C-deficient heterozygote treated with activated protein C therapy

A 13-month-old Japanese female with Haemophilus influenzae type b meningitis presented with unusually severe septic shock and cerebral infarction in half a day of fever. The initial therapy of plasma-derived activated protein C (Anact C) led to an impressive effect on the aggressive condition. However, purpura fulminans and the consistent decline of plasma protein C activity (<20%) required prolonged activated protein C therapy and gene analysis. The patient carried a novel heterozygous mutation of PROC (exon 4; 335 GAC>TAC, Asp46Tyr). This is the first report of infectious purpura fulminans in a protein C-deficient heterozygote. The clinical onset and treatment course adequately corroborated the aggravated immune/hemostatic reactions and the cytoprotective effects of activated protein C replacement in human heterozygous protein C deficiency. The monitoring of plasma protein C activity and sufficient administration of activated protein C product could improve the outcome of severe sepsis in children.

Immunotherapy in neonatal sepsis: advances in treatment and prophylaxis

PURPOSE OF REVIEW

Systemic infections in premature and term infants cause significant morbidity and mortality in spite of appropriate antimicrobial therapy. Consequently, immunotherapy has emerged as a potential adjuvant therapeutic modality to reduce the incidence and mortality associated with neonatal sepsis.

RECENT FINDINGS

The most recent findings during the review period include systematic reviews of previously published trials evaluating the use of intravenous immunoglobulin and colony-stimulating factors in neonatal sepsis. In addition, the most recent trials describing the use of antistaphylococcal antibodies, probiotics, glutamine supplementation, recombinant human protein C, and lactoferrin in the prevention and treatment of neonatal sepsis have been reviewed.

SUMMARY

Immunotherapy used as an adjuvant for the prevention and treatment of neonatal sepsis holds promise. Clinical trials specifically designed toward the neonatal population and appropriately powered to detect treatment differences are necessary prior to universal recommendation of these therapies in the nursery.