Pathogens Identified by Minimally Invasive Tissue Sampling in India and Pakistan From Preterm Neonatal Deaths: The PURPOSE Study

Risk factors and genetic characteristics of the carriage of hypervirulent and carbapenem-resistant Acinetobacter baumannii among pregnant women

Background

Carbapenem-resistant Acinetobacter baumannii (CRAB) and its emerging evolutionary branch toward hypervirulence have been neglected in pregnancy.

Methods

From September 2020 to August 2021, an active surveillance culture program encompassed 138 randomly selected pregnant women, with five subjected to sample collection at two different time points. The clinical characterization was explored through statistical analysis. Whole-genome sequencing, a Galleria mellonella infection model, and a global database were used to investigate the genetic characterization, pathogenicity, evolutionary history, and phylogenetic relationships of the isolates.

Results

Of the 41 CRAB isolates obtained, they were divided into four ClustersRS and an orphan pattern. ClusterRS 1 (n = 31), with eight complex types in pregnancy, was also the dominant ClusterRS globally, followed by ClusterRS 13 (n = 5), identified as hypervirulent KL49 CRAB, exhibiting phylogeographical specificity to Guangdong. A maternal carriage CRAB rate of 26.09% (36/138) was revealed, with half of the isolates representing novel complex types, prominently including CT3071, as the first KL7 isolates identified in Shenzhen. Both KL49 and KL7 isolates were most commonly found in the same participant, suggesting potential intraspecific competition as a possible reason for CRAB infection without carriers during pregnancy. The independent risk factors for carriers were revealed for the first time, including advanced maternal age, gestational diabetes mellitus, and Group B Streptococcus infection.

Conclusion

The significant carriage rate and enhanced virulence of CRAB during pregnancy emphasize the imperative for routine surveillance to forestall dissemination within this high-risk group, especially in Guangdong for ClusterRS 13 isolates.

Standardizing Minimally Invasive Tissue Sampling of Postmortem Brain Using Bard Monopty Needle in Newborns with Neurological Injury

INTRODUCTION

Minimally invasive tissue sampling of the brain in newborns using the Bard Monopty needle helps to diagnose various neurological conditions by obtaining relevant brain cores. We designed a modified procedure to provide maximum diagnostic utility in brain tissue biopsies.

METHOD

Twenty newborns underwent postmortem minimally invasive tissue sampling of the brain through the anterior fontanelle and posterior approach, using the engraved lines on the needle labeled from mark 0 to 13. The cores were correlated with conventional autopsy findings.

RESULTS

Meninges were best obtained at marks 0 and 1 from the anterior fontanelle and mark 1 from posterior fontenelle in 85% of cases. Periventricular brain parenchyma was best obtained from mark 3 and mark 1 from anterior and posterior fontanel, respectively in 90% cases. The sampling success in obtaining brain cores was 100%.

DISCUSSION

This modified technique increases the yield of meninges and brain tissue in newborns and aids in diagnosis.

Gut microbiota of preterm infants in the neonatal intensive care unit: a study from a tertiary care center in northern India

Introduction

Disruptions of the gut microbiota of preterm infants admitted to the neonatal intensive care unit (NICU) during the first 2 weeks of life are of critical importance. These infants are prone to various complications, including necrotizing enterocolitis (NEC) and sepsis. Studying the gut microbiota will improve outcomes in preterm infants. In the present study, we examined the gut microbiota of preterm infants admitted to the NICU in the first month of life.

Methods

Neonates admitted to the NICU were recruited, and stool samples were collected weekly from the seventh day of the infant's life until the 30th day of life. DNA was extracted using a DNeasy Powersoil DNA isolation kit. 16S rRNA gene sequencing targeting the V3-V4 region was performed using the MiSeq platform. Sequenced reads were processed on DADA2 pipeline to obtain an amplicon sequence variant (ASV) table. All bioinformatic and statistical analyses were performed using different packages in the R statistical framework.

Results

Fourteen preterm infants were recruited, and 48 samples were collected. Alpha diversity metrics, observed ASV count, and Shannon index were found to have no differences in any clinical variables. Permutational multivariate analysis of variance (PERMANOVA) showed discrimination of neonates by gestational age and administration of probiotics. Differential abundance analysis showed a decreased abundance of Bifidobacterium Breve in extremely preterm infants (gestational age <28 weeks) compared to moderate preterm infants (gestational age 29-32 weeks). Supplementation with probiotics decreased Acinetobacter and increased Bifidobacterium in the gut of preterm neonates regardless of gestational age.

Conclusion

Gestational age and probiotic supplementation alter the gut microbiota of preterm infants admitted to the NICU.

Group B streptococcal prevalence in internal organs and placentas of deceased neonates and stillbirths in South Asia

OBJECTIVE

Group B streptococcus (GBS) has been associated with adverse pregnancy outcomes, but few prospective studies have assessed its prevalence in low- and middle-income country settings. We sought to evaluate the prevalence of GBS by polymerase chain reaction (PCR) in internal organ tissues and placentas of deceased neonates and stillbirths.

DESIGN

This was a prospective, observational study.

SETTING

The study was conducted in hospitals in India and Pakistan.

POPULATION

Pregnant women with stillbirths or preterm births were recruited at delivery, as was a group of women with term, live births, to serve as a control group.

METHODS

A rectovaginal culture was collected from the women in Pakistan to assess GBS carriage. Using PCR, we evaluated GBS in various tissues of stillbirths and deceased neonates and their placentas, as well as the placentas of live-born preterm and term control infants.

MAIN OUTCOME MEASURES

GBS identified by PCR in various tissues and the placentas; rate of stillbirths and 28-day neonatal deaths.

RESULTS

The most obvious finding from this series of analyses from India and Pakistan was that no matter the country, the condition of the subject, the tissue studied or the methodology used, the prevalence of GBS was low, generally ranging between 3% and 6%. Among the risk factors evaluated, only GBS positivity in primigravidae was increased.

CONCLUSIONS

GBS diagnosed by PCR was identified in <6% of internal organs of stillbirths and neonatal deaths, and their placentas, and control groups in South Asian sites. This is consistent with other reports from South Asia and is lower than the reported GBS rates from the USA, Europe and Africa.

The PURPOSe cause of death study in stillbirths and neonatal deaths in India and Pakistan: A review

The PURPOSe study was a prospective, observational study conducted in India and Pakistan to determine the cause of death for stillbirths and preterm neonatal deaths, using clinical data together with minimally invasive tissue sampling (MITS) and the histologic and polymerase chain reaction (PCR) evaluation of fetal/neonatal tissues and the placenta. After evaluating all available data, an independent panel chose a maternal, a placental and a fetal/neonatal cause of death. Here, we summarise the major results. Among the most important findings were that most stillbirths were caused by fetal asphyxia, often preceded by placental malperfusion, and clinically associated with pre-eclampsia, placental abruption and a small-for-gestational-age fetus. The preterm neonatal deaths were primarily caused by birth asphyxia, followed by various infections. An important finding was that many of the preterm neonatal deaths were caused by a nosocomial infection acquired after neonatal intensive care (NICU) admission; the most common organisms were Acinetobacter baumannii, followed by Klebsiella pneumoniae, Escherichia coli/Shigella and Haemophilus influenzae. Group B streptococcus was less commonly present in the placentas or internal organs of the neonatal deaths.