Pentoxifylline for treatment of sepsis and necrotizing enterocolitis in neonates

Pentoxifylline for treatment of sepsis and necrotising enterocolitis in neonates

BACKGROUND

Mortality and morbidity due to neonatal sepsis and necrotising enterocolitis (NEC) remain high despite the use of potent antimicrobial agents. Agents that modulate inflammation may improve outcomes. Pentoxifylline (PTX), a phosphodiesterase inhibitor, is one such agent. This is an update of a review first published in 2003 and updated in 2011 and 2015.

OBJECTIVES

To assess the effectiveness and safety of intravenous PTX as an adjunct to antibiotic therapy on mortality and morbidity in neonates with suspected or confirmed sepsis and neonates with NEC.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and trial registries in July 2022. We also searched the reference lists of identified clinical trials and handsearched conference abstracts.   SELECTION CRITERIA: We included randomised controlled trials (RCTs) or quasi-RCTs assessing the efficacy of PTX with antibiotics (any dose or duration) for treatment of suspected or confirmed sepsis or NEC in neonates. We included three comparisons: (1) PTX with antibiotics compared to placebo or no intervention with antibiotics; (2) PTX with antibiotics compared to PTX with antibiotics and adjunct treatments such as immunoglobulin M-enriched intravenous immunoglobulin (IgM-enriched IVIG); (3) PTX with antibiotics compared to adjunct treatments such as IgM-enriched IVIG with antibiotics.

DATA COLLECTION AND ANALYSIS

We reported typical risk ratio (RR) and risk difference (RD) with 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) for continuous outcomes derived from a fixed-effect model of meta-analysis. We calculated the number needed to treat for an additional beneficial outcome (NNTB) if there was a statistically significant reduction in RD.

MAIN RESULTS

We identified no new studies for this update. We included six RCTs (416 neonates). All of the included studies examined neonates with sepsis; we identified no studies on neonates with NEC. Four of the six trials had high risk of bias for at least one risk of bias domain. Comparison 1: PTX with antibiotics compared to placebo with antibiotics, or antibiotics alone, in neonates with sepsis may reduce all-cause mortality during hospital stay (typical RR 0.57, 95% CI 0.35 to 0.93; typical RD -0.08, 95% CI -0.14 to -0.01; NNTB 13, 95% CI 7 to 100; 6 studies, 416 participants, low-certainty evidence) and may decrease length of hospital stay (LOS) (MD -7.74, 95% CI -11.72 to -3.76; 2 studies, 157 participants, low-certainty evidence). The evidence is very uncertain that PTX with antibiotics compared to placebo or no intervention results in any change in chronic lung disease (CLD) (RR 1.50, 95% CI 0.45 to 5.05; 1 study, 120 participants, very low-certainty evidence), severe intraventricular haemorrhage (sIVH) (RR 0.75, 95% CI 0.28 to 2.03; 1 study, 120 participants, very low-certainty evidence), periventricular leukomalacia (PVL) (RR 0.50, 95% CI 0.10 to 2.63; 1 study, 120 participants, very low-certainty evidence), NEC (RR 0.56, 95% CI 0.29 to 1.06; 6 studies, 405 participants, very low-certainty evidence), or retinopathy of prematurity (ROP) (RR 0.40, 95% CI 0.08 to 1.98; 1 study, 120 participants, very low-certainty evidence) in neonates with sepsis. Comparison 2: the evidence is very uncertain that PTX with antibiotics compared to PTX with antibiotics and IgM-enriched IVIG has any effect on mortality (RR 0.71, 95% CI 0.24 to 2.10; 102 participants, 1 study, very low-certainty evidence) or development of NEC in neonates with sepsis (RR 1.33, 95% CI 0.31 to 5.66; 1 study, 102 participants, very low-certainty evidence). The outcomes of CLD, sIVH, PVL, LOS, and ROP were not reported. Comparison 3: the evidence is very uncertain that PTX with antibiotics compared to IgM-enriched IVIG with antibiotics has any effect on mortality (RR 1.25, 95% CI 0.36 to 4.39; 102 participants, 1 study, very low-certainty evidence) or development of NEC (RR 1.33, 95% CI 0.31 to 5.66; 102 participants, 1 study, very low-certainty evidence) in neonates with sepsis. The outcomes of CLD, sIVH, PVL, LOS, and ROP were not reported. All of the included studies evaluated adverse effects due to PTX, but none were reported in the intervention group in any of the comparisons.

AUTHORS' CONCLUSIONS

Low-certainty evidence suggests that adjunct PTX therapy in neonatal sepsis may decrease mortality and length of hospital stay without any adverse effects. The evidence is very uncertain if PTX with antibiotics compared to PTX with antibiotics and IgM-enriched IVIG, or PTX with antibiotics compared to IgM-enriched IVIG with antibiotics, has any effect on mortality or development of NEC. We encourage researchers to undertake well-designed multicentre trials to confirm or refute the effectiveness and safety of pentoxifylline in reducing mortality and morbidity in neonates with sepsis or NEC.

Neonatal Sepsis-Newer Insights

Sepsis is one of the leading causes of mortality and morbidity among neonates worldwide and especially affects the preterm neonates in resource-restricted settings. The infection may be acquired in utero, from the mother's genital tract or postnatally from the community or hospital environment and personnel. Factors including the time of exposure, size of the inoculum, immunity in the host, and virulence of the infectious agent affect the severity and course of illness. Culture-independent diagnostics, sepsis prediction scores, antibiotic stewardship, and preventive strategies including hand hygiene are ongoing efforts for reducing the neonatal sepsis burden.

Protocol: Pentoxifylline optimal dose finding trial in preterm neonates with suspected late onset sepsis (PTX-trial)

BACKGROUND

Late onset sepsis is a leading cause of death and morbidity in preterm infants. Despite optimal antibiotic treatment, sepsis related mortality and morbidity is still high. Pentoxifylline (PTX) is a methylxanthine with promising immunomodulatory properties, which can be used as an additional therapy next to antibiotics in preterm infants. PTX is increasingly used off-label in neonatal intensive care units, however up till now no dose finding study has been done for PTX in this specific population. The aim of this study (PTX-trial) is to determine the optimal dose of PTX in preterm infants (gestational age < 30 weeks) with (suspected) late onset sepsis. Dose finding in this particular population is unique, since for most drugs used in neonates the optimal dosage has not been investigated in phase II dose-seeking studies.

METHODS

The PTX-trial is a prospective open label sequential dose-optimization study with an adapted continual reassessment method. An up-and-down dose-response design will be used, with dose step-up and step-down titration after every 3 patients. The PTX starting dosage will be 30 mg/kg/day in 6 hours as described in most previous neonatal studies. Efficacy is defined by means of biochemical and clinical parameters. Toxicity in these vulnerable patients is unwarranted. The optimal dose is defined as the ED75 (i.e., clinically and chemically effective dose for 75% of patients) in preterm neonates with late onset sepsis. We plan to include 30 neonates to determine the optimal dose using this study design. Subsequently, the optimal dose will be validated in 10 additional preterm neonates. In parallel, pharmacokinetics of PTX and its metabolites will be described as well as longitudinal evaluation of metabolomics and proteomics.

DISCUSSION

The study has been approved by the Regional Medical Ethics Board of Erasmus Medical Center University Rotterdam (MEC 2019-0477) and registered at Clinicaltrials.gov (NCT04152980). Results of the main trial and each of the secondary endpoints will be submitted for publications in peer-reviewed journals.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04152980 , Registered November 6th, 2019.

Neonatal Sepsis

Neonatal sepsis is associated with severe morbidity and mortality in the neonatal period. Clinical manifestations range from subclinical infection to severe local or systemic infection. Neonatal sepsis is divided into three groups as early-onset neonatal sepsis, late-onset neonatal sepsis and very late-onset neonatal sepsis according to the time of the onset. It was observed that the incidence of early-onset neonatal sepsis decreased with intrapartum antibiotic treatment. However, the incidence of late-onset neonatal sepsis has increased with the increase in the survival rate of preterm and very low weight babies. The source of the causative pathogen may be acquisition from the intrauterine origin but may also acquisition from maternal flora, hospital or community. Prematurity, low birth weight, chorioamnionitis, premature prolonged rupture of membranes, resuscitation, low APGAR score, inability to breastfeed, prolonged hospital stay and invasive procedures are among the risk factors. This article reviews current information on the definition, classification, epidemiology, risk factors, pathogenesis, clinical symptoms, diagnostic methods and treatment of neonatal sepsis.

Effects of maturation and size on population pharmacokinetics of pentoxifylline and its metabolites in very preterm infants with suspected late-onset sepsis or necrotizing enterocolitis: a pilot study incorporating clinical outcomes

AIMS

Infection-induced inflammation is associated with adverse long-term outcomes in preterm infants. Pentoxifylline (PTX) is a candidate for adjunct immunomodulatory therapy in preterm infants with late-onset sepsis (LOS) and necrotizing enterocolitis (NEC), but pharmacokinetic data in this population are extremely limited. This study aims to characterize the pharmacokinetic properties of intravenous PTX and its metabolites in preterm infants.

METHOD

An open label pilot clinical study of intravenous PTX as an adjunct therapy in preterm infants (gestation <32 weeks) with suspected LOS or NEC was undertaken. PTX was infused for 12 h for two days (60 mg kg^-1 per 12 h), and in infants with confirmed diagnosis of LOS or NEC, for 6 h for another 4 days (30 mg kg^-1 per 6 h). Plasma concentrations of PTX and its principal metabolites from collected blood samples were measured using a validated LCMS assay. NONMEM was used to analyse the data using population pharmacokinetic modelling.

RESULTS

The preterm infants (n = 26) had a median (range) gestation of 24.8 weeks (23.3-30.4) and birthweight of 689 g (370-1285). PTX was well tolerated and without treatment-limiting adverse effects. Changes in size (weight) and maturation were successfully modelled for PTX and metabolites. After allometric scaling, clearance increased with postmenstrual age, increasing by approximately 30% per week for PTX and M1 (lisofylline) and simulations of current dosing demonstrated a six-fold difference in exposure between 24 and 35 weeks postmenstrual age.

CONCLUSIONS

The developed model can be used to explore dosing strategies based on size and maturation for preterm infants.

The initial prophylactic antibiotic usage and subsequent necrotizing enterocolitis in high-risk premature infants: a systematic review and meta-analysis

OBJECTIVE

To investigate the correlation between the initial prophylactic antibiotic use and the subsequent NEC in high-risk premature infants.

METHODS

We performed a literature search of PubMed, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), and the Web of Science, and nine studies with a total of 5207 infants were selected for inclusion in this study.

RESULTS

The pooled estimate for the seven studies combined indicating that prophylactic antibiotic usage was associated with a non-significant trend toward increased incidence of NEC [odds ratio (OR) 0.75; 95% confidence interval (CI) 0.26-2.17], and prolonged exposure to prophylactic antibiotics, compared with limited prophylactic antibiotic use, was associated with a significant trend toward the risk of increasing incidence of NEC (OR 1.31; 95% CI 1.08-1.59).

CONCLUSION

Current evidence does not support the use of prophylactic antibiotics to reduce the incidence of NEC for high-risk premature infants.

Neonatal sepsis

Neonatal sepsis is the cause of substantial morbidity and mortality. Precise estimates of neonatal sepsis burden vary by setting. Differing estimates of disease burden have been reported from high-income countries compared with reports from low-income and middle-income countries. The clinical manifestations range from subclinical infection to severe manifestations of focal or systemic disease. The source of the pathogen might be attributed to an in-utero infection, acquisition from maternal flora, or postnatal acquisition from the hospital or community. The timing of exposure, inoculum size, immune status of the infant, and virulence of the causative agent influence the clinical expression of neonatal sepsis. Immunological immaturity of the neonate might result in an impaired response to infectious agents. This is especially evident in premature infants whose prolonged stays in hospital and need for invasive procedures place them at increased risk for hospital-acquired infections. Clinically, there is often little difference between sepsis that is caused by an identified pathogen and sepsis that is caused by an unknown pathogen. Culture-independent diagnostics, the use of sepsis prediction scores, judicious antimicrobial use, and the development of preventive measures including maternal vaccines are ongoing efforts designed to reduce the burden of neonatal sepsis.

Pentoxifylline during steroid window phase at induction to remission increases apoptosis in childhood with acute lymphoblastic leukemia

PURPOSE

Pentoxifylline (PTX) has been shown to increase chemotherapy-induced apoptosis. A clinical trial was developed to evaluate the effect of the addition of PTX to the induction steroid window phase in children with acute lymphoblastic leukemia (ALL).

METHODS

Thirty-two children were enrolled on this study. Children with a new diagnosis of ALL were randomly assigned to receive prednisone (PRD) 40 mg/m(2)/day only during the 7-day treatment pre-phase (PRD group, 11 patients) or to receive PRD with PTX (10 mg/kg/day) (PTX group, 11 patients); the control group included children with normal bone marrow (10 patients). Bone marrow aspiration (BMA) was performed at diagnosis (day -7) in all groups, and at day 0 (end of PRD window) for patients with ALL (PRD and PTX groups). Apoptosis was evaluated by flow cytometry (FC) using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) stains. Statistical analysis was performed using the Mann-Whitney U test.

RESULTS

Apoptotic index at day -7 was similar in all groups. However, at day 0 post-treatment, apoptosis was significantly higher in the PTX group than in the PRD group (p < 0.001). There were no serious adverse effects associated with PTX.

CONCLUSIONS

PTX potentiates blast apoptosis induced by PRD in children with ALL during steroid window phase.

Pentoxifylline immunomodulation in the treatment of experimental chronic pulmonary paracoccidioidomycosis

Background

Pentoxifylline (PTX) is a methylxanthine compound with immunomodulatory and antifibrotic properties. The simultaneous use of PTX and antifungal therapy (itraconazole) has previously been evaluated in an experimental model of pulmonary paracoccidioidomycosis (PCM), a systemic fungal disease caused by the fungus Paracoccidioides brasiliensis (Pb) and characterized by chronic inflammation and lung fibrosis that appears even after a successful course of antifungal therapy. The results revealed prompt and statistically significant reductions in inflammation and fibrosis when compared to itraconazole alone. However, the effect of monotherapy with PTX on the host response to PCM has not been well-documented. Our aim was to determine the effect of PTX on the course of pulmonary lesions and on the local immune response.

Results

At the middle and end of treatment, the Pb-infected-PTX-treated mice exhibited significant reductions in lung density compared to the Pb-infected-non-treated mice as assessed by the quantification of Hounsfield units on high-resolution computed tomography (HRCT) (p <0.05 by Kruskal-Wallis test); additionally, at the end of therapy, the lung areas involved in the inflammatory reactions were only 3 vs. 22 %, respectively, by histomorphometry (p <0.05 by Mann–Whitney test), and this reduction was associated with a lower fungal burden and limited collagen increment in the pulmonary lesions. PTX treatment restored the levels of IFN-γ, MIP-1β, and IL-3 that had been down-regulated by Pb infection. Additionally, IL-12p70, IL-10, IL-13, and eotaxin were significantly increased, whereas Regulated upon Activation, Normal T cell Expressed and Secreted (RANTES) levels were decreased in the lungs of the Pb-infected-PTX-treated mice compared to the non-treated group.

Conclusions/significance

This study showed that PTX therapy administered at an “early” stage of granulomatous inflammation controlled the progress of the PCM by diminishing the pulmonary inflammation and the fungal burden and avoiding the appearance of collagen deposits in the pulmonary lesions.

Probiotics (Lactobacillus acidophilus and Bifidobacterium infantis) prevent NEC in VLBW infants fed breast milk but not formula [corrected]

BACKGROUND

Specific probiotics prevent necrotizing enterocolitis (NEC). A mixture of lactobacilli and bifidobacteria (Infloran) was highly effective in Asian very-low-birth-weight (VLBW) infants. We analyzed the effect of Infloran on NEC, NEC severity, and the influence of enteral feedings (breast milk vs. formula) on NEC prevention in a cohort of European VLBW infants.

METHODS

Infloran was implemented for routine use at our department. VLBW infants receiving probiotics were prospectively followed (2010-2012) and compared with historic controls (2008-2009). Data on NEC, neonatal morbidity, feeding tolerance, and descriptive parameters on NEC cases were analyzed.

RESULTS

Infloran had no statistically significant impact on NEC (controls: 24/233 (10.3%); probiotics: 16/230 (7%); P = 0.2). However, NEC was significantly reduced in infants of the probiotics group who were fed any breast milk (20/179 (11.2%) vs. 10/183 (5.5%); P = 0.027), whereas it was ineffective in infants exclusively fed formula (4/54 (7.4%) vs. 6/44 (13.6%); P = 0.345). Occurrence of severe NEC (IIIb), time until full feeds, and gastric residuals were similar.

CONCLUSION

Infloran was of lower efficacy in a European VLBW cohort and showed a reduction of NEC only in infants fed breast milk. Future studies should investigate the influence of feeding formula or breast milk on the effect of probiotics.

Pentoxifylline for the prevention of bronchopulmonary dysplasia in preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a common complication in preterm infants. BPD is associated with poor long-term respiratory and neurodevelopmental outcome and increased mortality. The prophylactic use of agents that modulate inflammation such as pentoxifylline, a synthetic methylxanthine and phosphodiesterase inhibitor, may reduce the incidence of BPD.

OBJECTIVES

The primary objective of this review was to determine the effect of pentoxifylline on the incidence of BPD, death prior to 36 weeks postmenstrual age (PMA), and BPD or death prior to 36 weeks PMA in preterm neonates.

SEARCH METHODS

We searched the Cochrane Neonatal Review Group Specialized Register, CENTRAL (The Cochrane Library Issue 9, 2012), EMBASE (January 1974 to September 2012), PubMed (January 1966 to September 2012), and CINAHL (January 1982 to September 2012) in September 2012. We checked references and cross-references from identified studies. We handsearched abstracts from the proceedings of the Pediatric Academic Societies Meetings (from January 1990 to September 2012). We placed no restrictions on language.

SELECTION CRITERIA

Randomised or quasi-randomised clinical trials of systemic or nebulised pentoxifylline in preterm neonates less than 32 weeks gestational age or less than 1500 g birth weight, reporting on at least one outcome of interest, were eligible for inclusion in the review.

DATA COLLECTION AND ANALYSIS

We used the standard methods of the Cochrane Neonatal Review Group and The Cochrane Collaboration. Two review authors (SMS and SK) independently searched the literature as described above and selected studies. Any disagreements were resolved by discussion involving all review authors.

MAIN RESULTS

We identified one randomised clinical trial eligible for inclusion in this review. This study compared the use of nebulised pentoxifylline versus placebo for prevention of BPD in 100 preterm infants and was at high risk of bias due to lack of blinding of intervention and outcome assessors, and incomplete outcome data. There was no statistically significant effect of nebulised pentoxifylline versus placebo on individual outcomes of BPD at 36 weeks PMA or on death prior to 36 weeks PMA. There was no significant effect of nebulised pentoxifylline on intraventricular haemorrhage, periventricular leukomalacia, sepsis, or patent ductus arteriosus (PDA) requiring ligation. The study did not report any of the other secondary outcomes considered for this review. Reporting of adverse events was very limited and did not allow for reliable judgement on the incidence of such events. No long-term outcomes were reported.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine the safety and efficacy of pentoxifylline for prevention of BPD in preterm neonates. We encourage researchers to conduct clinical trials to confirm or refute the role of pentoxifylline for prevention of BPD in preterm neonates. These trials should report on clinically important outcomes and, ideally, on long-term neurodevelopmental outcome.

Update on the management of neonatal sepsis in horses

Despite advances in neonatal intensive care sepsis, severe sepsis and septic shock remain the biggest killers of neonatal foals. Management of this severe syndrome remains difficult, requiring intensive intervention. Key aspects of management include infection control, hemodynamic support, immunomodulatory interventions, and metabolic/endocrine support. Infection control largely consists of early antimicrobial therapy, plasma transfusions, and local therapy for the infected focus. In cases with severe sepsis or septic shock, hemodynamic support with fluids, vasoactive agents, and respiratory support insuring oxygen delivery to vital organs is important. Nutritional support is important, but close monitoring is needed to avoid hyperglycemia and hypoglycemia.

Infection-induced inflammation and cerebral injury in preterm infants

Preterm birth and infectious diseases are the most common causes of neonatal and early childhood deaths worldwide. The rates of preterm birth have increased over recent decades and account for 11% of all births worldwide. Preterm infants are at significant risk of severe infection in early life and throughout childhood. Bacteraemia, inflammation, or both during the neonatal period in preterm infants is associated with adverse outcomes, including death, chronic lung disease, and neurodevelopmental impairment. Recent studies suggest that bacteraemia could trigger cerebral injury even without penetration of viable bacteria into the CNS. Here we review available evidence that supports the concept of a strong association between bacteraemia, inflammation, and cerebral injury in preterm infants, with an emphasis on the underlying biological mechanisms, clinical correlates, and translational opportunities.

Novel treatments for NEC: keeping IBD in mind

Necrotizing enterocolitis (NEC) is an inflammatory intestinal disease of premature newborns, thought to result in part from overactivity of the innate immune system. NEC has been well-studied from the perspective of prevention; however, after the disease onset, there are limited treatment options to control its progression. This review discusses four potential therapies that target the overactive immune response in NEC: pentoxifylline, platelet activating factor modulators, glucocorticoids, and vasoactive substances. In addition, given the similar pathogenesis of NEC and inflammatory bowel disease (IBD), we propose that IBD therapies could provide promising leads for novel strategies with which to treat NEC.