Incidence of pneumonia, bacteremia, and invasive pneumococcal disease in Pakistani children

Critical illness related to community acquired pneumonia, its epidemiology and outcomes in a pediatric intensive care unit of Pakistan

BACKGROUND

To determine the epidemiology and outcomes in critically ill children admitted with severe community acquired pneumonia (CAP) and to identify risk factors associated with mortality in a pediatric intensive care unit (PICU) METHODS: Retrospective review of medical records of all children (age 1 month to 18 years) admitted to PICU with CAP from January 2013 to March 2018 was done. Patients admitted in last 2 weeks before current illness and those with bronchiolitis (based on clinical diagnosis) were excluded. Data were collected on a structured proforma and included demographic, clinical data, comorbidities, therapeutic information, laboratory data, and outcome data. Results were presented as mean with SD and frequency with percentages. Factors associated with mortality were analyzed, using logistic regression for both univariate and multivariate analyses.

RESULTS

A total of 187 children with severe CAP were identified, 53.5% (n = 100) were <1 year of age and 65.2% (n = 122) were male, 32.6% (n = 61) were underweight, and 24.6% (n = 46) were stunted. A total of 94% (175) required mechanical ventilation. Mortality among the cohort was 20.3% (n = 38) with median length of mechanical ventilation 4 (2-8) days, and median length of PICU stay was 6 (4-12) days. PRISM score >10 on admission, presence of systemic illness, empyema, and length of PICU stay 14 (±2) days were associated with increased mortality among critically ill children admitted with CAP (p < .05).

CONCLUSIONS

Severe illness on presentation, presence of systemic illness and empyema are associated with increased mortality in children admitted to the PICU with severe CAP.

Microbial Patterns and Antibiotic Susceptibility in Blood Culture Isolates of Septicemia Suspected Children in the Pediatrics Ward of a Tertiary Care Hospital

Objectives  This study aims to determine microbial patterns and antibiotic susceptibility to alert clinicians to the emerging pathogens that may pose a threat to the community, especially children.

Materials and Methods  This retrospective cross-sectional study was conducted in the Department of Pathology, Holy Family Hospital, Rawalpindi, Pakistan, from July 2019 to December 2019. Two samples were taken from two different sites of each patient at the time of fever (> 100° F) to avoid chances of contamination. A blood sample of 5 to 10 mL was drawn from each site. In a 50 mL brain heart infusion broth (BHIB), 5 to 10% blood was injected in two different bottles and incubated for 48 hours at 37°C. After 48 hours, subculture was done by streaking the drops of blood samples taken from BHIB on blood and MacConkey agar. Cultures were incubated in aerobic conditions at 37°C for 24 to 48 hours. For testing antibiotic susceptibility, criteria defined by the Clinical and Laboratory Standards Institute (CLSI) were followed. Microbes were identified under a microscope by observing their morphological characteristics after gram staining and applying biochemical tests. Antibiotic sensitivity test was performed using standard aseptic methods.

Statistical Analysis  Bacterial isolates and their susceptibility patterns were represented using frequencies and percentage charts.

Results  Out of 423 blood cultures, growth was recorded in 92 (21.75%) of the cultures with female to male ratio 2.1:1. The gram-positive bacteria accounted for 43.48% ( n = 40), whereas gram-negative bacteria covered the majority 54.36% ( n = 50). Among isolates, Staphylococcus aureus (42.39%) was the most common, followed by Acinetobacter spp. (17.39%) and Pseudomonas aeruginosa (14.13%). Acinetobacter spp. showed 0% susceptibility to amikacin and cefotaxime. All the isolates were 100% resistant to amoxicillin-clavulanic acid. S. aureus showed lower sensitivity for ceftazidime (0%), clindamycin (66.67%), ciprofloxacin (0%), clarithromycin (11.76%), and ceftriaxone (0%). Tigecycline showed 100% sensitivity for all isolates tested.

Conclusion  Gram-negative bacteria form the majority of isolates in our setup, with Acinetobacter as the most common species among them. The resistance against cephalosporins, penicillin, and fluoroquinolones shown by Acinetobacter , Pseudomonas , Salmonella, and Klebsiella is of grave concern. Among gram-positive bacteria, S. aureus has established resistance against multiple drugs. Limited and objective use of antibiotic therapy is a much-needed strategy under new guidelines.

Direct and indirect effect of 10 valent pneumococcal vaccine on nasopharyngeal carriage in children under 2 years of age in Matiari, Pakistan

Background

Pakistan introduced Ten-valent pneumococcal-conjugate-vaccine PCV10 in 2012 as a 3 + 0 schedule without catch-up.

Methods

Children <2 years old in Matiari, Sindh provided nasopharyngeal swabs between 2014 and 2018, which were cultured for pneumococcus and serotyped through multiplex PCR at the Aga Khan University Hospital. Carriage rates over time for Vaccine-Type (VT) and Non-VT (NVT) serotypes were used to estimate direct, indirect, total and overall effects of vaccination. Regression analysis was used to determine factors associated with VT carriage.

Results

Pneumococcus was detected in 2370/3140 (75%). VT carriage decreased overall, 16.1–9.6% (p-trend <0.001); vaccinated (all 3 doses of PCV10 received) 11.3–8.1% (p-trend 0.031) and unvaccinated (no PCV10 dose received) 17.4–10.3% (p-trend 0.003) with a decline in serotypes 6B, 9V/9A and 19F. Immunization increased from 41.0% to 68.4% (p-trend 0.001). Direct effect of vaccine was 32.8% (95% CI 14.7–47.0%) and indirect effect 44.6%(95% CI 40.6–48.6%). Factors associated with decreased VT colonization were education 1–5 years (aOR 0.7, 95%CI 0.6–1.0), history of difficulty breathing (aOR 0.7, 95%CI 0.5–1.0), exposure to smoke (aOR 0.8, 95% CI 0.6–1.0), child fully immunized (aOR 0.7, 95%CI 0.5–1.0) and enrolled in 3rd (aOR 0.6, 95%CI 0.4–0.8) and 4th (aOR 0.6, 95%CI 0.5–0.9) year of the study whereas history of runny nose (aOR 1.5, 95% CI 1.2–1.9) was positively associated.

Conclusions

Decrease in VT pneumococcal carriage in vaccinated and unvaccinated children indicates herd immunity. Sustained increase in vaccine coverage and close long-term surveillance is warranted.

A Community-Based Survey on Health-Care Utilization for Pneumonia in Children in Peri-Urban Slums of Karachi, Pakistan

Pneumonia, as defined by WHO, is a syndromic diagnosis characterized by presence of cough or difficult breathing. Presentation to health-care provider depends on timely identification of signs and symptoms by caretakers. We explored patterns of health-care utilization among caretakers of a randomly selected sample of 1,152 children aged 2-59 months, residing in low-income settlements of Karachi, Pakistan. Information on household demographics, occurrence of pneumonia-specific symptoms, care seeking, air quality, and knowledge regarding preventive measures for pneumonia was collected. Predictors of care seeking were estimated using weighted logistic regression. Prevalence of pneumonia with cough and rapid or difficulty in breathing was found to be 40.8% and 37.1% in infants (2-11 months) and children (12-59 months), respectively. Ninety-five percentage of caretakers sought care, 68.5% privately. Odds ratios (ORs) for independent predictors of care-seeking were as follows: younger age of child (infants compared with children), 3.60 (95% CI = 2.65-4.87); caretaker with primary education compared with none, 3.40 (2.46-4.70); vaccine awareness, 1.65 (1.45-1.87); and breastfeeding awareness, 1.32 (1.13-1.53). Presence of symptoms such as fever OR, 1.51 (1.30-1.76); tachypnea, 1.57 (1.35-1.83); chest indrawing, 2.56 (2.05-3.18); persistent vomiting, 1.69 (1.37-2.09); and recurrent illness, 2.57 (2.23-2.97) were also predictive. There is high health-care utilization for pneumonia with the skewed presentation toward private services. Strategies should be focused on making pneumonia care standardized, efficient and affordable, especially in the private sector.

Nasopharyngeal carriage of Streptococcus pneumoniae in children under 5 years of age before introduction of pneumococcal vaccine (PCV10) in urban and rural districts in Pakistan

Background

Benefits of pneumococcal conjugate vaccine programs have been linked to the vaccine’s ability to disrupt nasopharyngeal carriage and transmission. The 10-valent pneumococcal vaccine (PCV10) was included in the Expanded Program on Immunization (EPI) in Sindh, Pakistan in February 2013. This study was carried out immediately before PCV10 introduction to establish baseline pneumococcal carriage and prevalent serotypes in young children and to determine if carriage differed in urban and rural communities.

Methods

Nasopharyngeal specimens were collected from a random sample of children 3-11 and 12-59 months of age in an urban community (Karachi) and children 3-11 months of age in a rural community (Matiari). Samples were processed in a research laboratory in Karachi. Samples were transported in STGG media, enriched in Todd Hewitt broth, rabbit serum and yeast extract, cultured on 5% sheep blood agar, and serotyped using the CDC standardized sequential multiplex PCR assay. Serotypes were categorized into PCV10-type and non-vaccine types.

Results

We enrolled 670 children. Pneumococci were detected in 73.6% and 79.5 % of children in the infant group in Karachi and Matiari, respectively, and 78.2% of children 12 to 59 months of age in Karachi. In infants, 38.9% and 33.5% of those carrying pneumococci in Karachi and Matiari, respectively, had PCV10 types. In the older age group in Karachi, the proportion was 30.7%, not significantly different from infants. The most common serotypes were 6A, 23F, 19A, 6B and 19F.

Conclusion

We found that about 3 of 4 children carried pneumococci, and this figure did not vary with age group or urban or rural residence. Planned annual surveys in the same communities will inform change in carriage of PCV10 serotype pneumococci after the introduction and uptake of PCV10 in these communities

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3608-5) contains supplementary material, which is available to authorized users.

Molecular Characterization of Pneumococcal Surface Protein A (PspA), Serotype Distribution and Antibiotic Susceptibility of Streptococcus pneumoniae Strains Isolated from Pakistan

INTRODUCTION

Pakistan has one of the highest burdens of pneumococcal diseases in the world, but unfortunately studies in this demanding research area are limited in the region. Pneumococcal surface protein A (PspA) is the next generation pneumococcal vaccine candidate as the protein locates on the Streptococcus pneumoniae surface. Its gene, pspA, might be encoded by all pneumococci, and the protein has proven immunogenicity. The molecular characterization of PspA, pneumococcal serotype distribution and antibiotic susceptibility are important for regional diversity studies.

METHODS

In this study, we examined 38 pneumococcal isolates from pneumococcal diseased (pneumonia/meningitis) patients blood or cerebrospinal fluid. There were no specific inclusion or exclusion criteria, but all the individuals [ages 1 month to 12 years (male/female)] had undergone no antibiotic treatment in at least the past 3 months and had no vaccination history. We investigated the serotype distribution, antibiotic susceptibility, prevalence of the PspA family and its active domain's fusion, expression and antigenicity.

RESULTS

Our finding shows that serotype 19F is the most prevalent (23.6%) followed by 18B (15.78%) (non-vaccine type) in all isolated pneumococcal strains. All strains were susceptible to chloramphenicol and linezolid, while 80% were resistant to gentamycin. Genotyping revealed that ~ 80% (N = 31/38) of pneumococcal strains produce PspA belonging to family 2 and clade 3. We further selected three active domains of PspA (family 2 and clade 3) by in silico analysis, merged together into a fusion gene for expression study, and its antigenicity was analyzed by Western blotting.

CONCLUSION

Serotypes 19F and 18B (non-vaccine type) are the most prevalent in the Pakistani pneumococcal isolates. The PspA family 2 proteins produced by Pakistani pneumococcal isolates have high sequence homologies with each other and differ from those produced by strains isolated in the rest of the world. The PspA fusion peptide had a proven antigenic response in western blotting, with no considerable correlation among pneumococcal serotypes, antibiotic susceptibility and PspA family/clade distribution.

Profile: Health and Demographic Surveillance System in peri-urban areas of Karachi, Pakistan

The Aga Khan University’s Health and Demographic Surveillance System (HDSS) in peri urban areas of Karachi was set up in the year 2003 in four low socioeconomic communities and covers an area of 17.6 square kilometres. Its main purpose has been to provide a platform for research projects with the focus on maternal and child health improvement, as well as educational opportunities for trainees. The total population currently under surveillance is 249,128, for which a record of births, deaths, pregnancies and migration events is maintained by two monthly household visits. Verbal autopsies for stillbirths, deaths of children under the age of five years and adult female deaths are conducted. For over a decade, the HDSS has been a platform for a variety of studies  including, calculation of the incidence of various infectious diseases like typhoid bacteremia, pneumonia and diarrhea, evaluation of effectiveness of various treatment regimens for neonatal sepsis, assessment of the acceptance of hospitalized care, determination of the etiology of moderate to severe diarrhea, assessment of burden and etiology of neonatal sepsis and a multi-centre cohort study measuring the burden of stillbirths, neonatal and maternal deaths. We have also established a bio-repository of a well-defined maternal and newborn cohort. Through a well-established HDSS rooted in maternal and child health we aim to provide concrete evidence base to guide policy makers to make informed decisions at local, national and international levels.

The pediatric disease spectrum in emergency departments across Pakistan: data from a pilot surveillance system

BACKGROUND

There is an increasing number of urgently ill and injured children being seen in emergency departments (ED) of developing countries. The pediatric disease burden in EDs across Pakistan is generally unknown. Our main objective was to determine the spectrum of disease and injury among children seen in EDs in Pakistan through a nationwide ED-based surveillance system.

METHODS

Through the Pakistan National Emergency Department Surveillance (Pak-NEDS), data were collected from November 2010 to March 2011 in seven major tertiary care centers representing all provinces of Pakistan. These included five public and two private hospitals, with a collective annual census of over one million ED encounters.

RESULTS

Of 25,052 children registered in Pak-NEDS (10% of all patients seen): 61% were male, 13% under 5 years, while almost 65% were between 10 to < 16 years. The majority (90%) were seen in public hospital EDs. About half the patients were discharged from the EDs, 9% admitted to hospitals and only 1.3% died in the EDs. Injury (39%) was the most common presenting complaint, followed by fever/malaise (19%) and gastrointestinal symptoms (18%). Injury was more likely in males vs. females (43% vs. 33%; p < 0.001), with a peak presentation in the 5-12 year age group (45%).

CONCLUSIONS

Pediatric patients constitute a smaller proportion among general ED users in Pakistan. Injury is the most common presenting complaint for children seen in the ED. These data will help in resource allocation for cost effective pediatric ED service delivery systems. Prospective longer duration surveillance is needed in more representative pediatric EDs across Pakistan.

Burden of invasive pneumococcal disease in children aged 1 month to 12 years living in South Asia: a systematic review

Objective

The primary objective was to estimate the burden of invasive pneumococcal disease (IPD) in children aged 1 month to 12 years in South Asian countries.

Methods

We searched three electronic databases (PubMed, Embase and the Cochrane Library) using a comprehensive search strategy, we manually searched published databases (Index Medicus and Current Contents) and we also searched the bibliographies of the included studies and retrieved reviews. The searches were current through June 2013. Eligible studies (community-based and hospital-based) were pooled and a separate analysis for India was also completed. A meta-regression analysis and heterogeneity analysis were performed. The protocol was registered with PROSPERO registration number CRD42013004483.

Results

A total of 22 studies surveying 36,714 children were included in the systematic review. Hospital-based prospective studies from South Asia showed that 3.57% of children had IPD, and 15% of all bacterial pneumonia cases were due to Streptococcus pneumoniae. Indian studies showed that the incidence of IPD was 10.58% in children admitted to hospitals with suspected invasive bacterial diseases, and 24% of all bacterial pneumonia cases were due to S. pneumonia. Population-based studies from South Asian countries showed that 12.8% of confirmed invasive bacterial diseases were caused by S. pneumonia whereas retrospective hospital-based studies showed that 28% of invasive bacterial diseases were due to S. pneumoniae. Meta-regression showed that there was a significant influence of the antigen testing method for diagnosing IPD on IPD prevalence.

Conclusion

S. pneumoniae is responsible for a substantial bacterial disease burden in children of South Asian countries including India despite the presence of high heterogeneity in this meta-analysis. Treatment guidelines must be formulated, and preventive measures like vaccines must also be considered.

Effectiveness of Haemophilus influenzae type b conjugate vaccine on radiologically-confirmed pneumonia in young children in Pakistan

OBJECTIVE

The effectiveness of Haemophilus influenzae type b (Hib) vaccine in preventing severe pneumonia in Asian children has been questioned, and many large Asian countries yet to introduce Hib conjugate vaccine in immunization programs. The primary objective of this study was to assess Hib conjugate vaccine effectiveness (VE) on radiologically-confirmed pneumonia in children born after introduction of Hib conjugate vaccine in Pakistan.

STUDY DESIGN

A matched case-control study enrolled cases of radiologically-confirmed pneumonia in several hospitals serving low-income populations during 2009-2011. Cases were matched by age and season with 3 hospital and 5 neighborhood controls. Pneumonia was diagnosed using standardized World Health Organization criteria for chest radiograph interpretation. Matched OR were estimated for VE.

RESULTS

A total of 1027 children with radiologically-confirmed pneumonia were enrolled; 975 cases, 2925 hospital controls, and 4875 neighborhood controls were analyzed. The coverage for 3 doses of diphtheria-tetanus-pertussis-hepatitis B-Hib conjugate vaccine was 13.7%, 18%, and 22.7% in cases, hospital controls and neighborhood controls, respectively. Estimated Hib VE for radiologically-confirmed pneumonia was 62% with 3 doses of vaccine using hospital controls and 70% using neighborhood controls.

CONCLUSIONS

Hib conjugate vaccine prevented a significant fraction of radiologically-confirmed pneumonia in children in Pakistan. Maximizing impact on child survival needs improved immunization coverage.

Global and regional burden of hospital admissions for severe acute lower respiratory infections in young children in 2010: a systematic analysis

BACKGROUND

The annual number of hospital admissions and in-hospital deaths due to severe acute lower respiratory infections (ALRI) in young children worldwide is unknown. We aimed to estimate the incidence of admissions and deaths for such infections in children younger than 5 years in 2010.

METHODS

We estimated the incidence of admissions for severe and very severe ALRI in children younger than 5 years, stratified by age and region, with data from a systematic review of studies published between Jan 1, 1990, and March 31, 2012, and from 28 unpublished population-based studies. We applied these incidence estimates to population estimates for 2010, to calculate the global and regional burden in children admitted with severe ALRI in that year. We estimated in-hospital mortality due to severe and very severe ALRI by combining incidence estimates with case fatality ratios from hospital-based studies.

FINDINGS

We identified 89 eligible studies and estimated that in 2010, 11·9 million (95% CI 10·3-13·9 million) episodes of severe and 3·0 million (2·1-4·2 million) episodes of very severe ALRI resulted in hospital admissions in young children worldwide. Incidence was higher in boys than in girls, the sex disparity being greatest in South Asian studies. On the basis of data from 37 hospital studies reporting case fatality ratios for severe ALRI, we estimated that roughly 265,000 (95% CI 160,000-450,000) in-hospital deaths took place in young children, with 99% of these deaths in developing countries. Therefore, the data suggest that although 62% of children with severe ALRI are treated in hospitals, 81% of deaths happen outside hospitals.

INTERPRETATION

Severe ALRI is a substantial burden on health services worldwide and a major cause of hospital referral and admission in young children. Improved hospital access and reduced inequities, such as those related to sex and rural status, could substantially decrease mortality related to such infection. Community-based management of severe disease could be an important complementary strategy to reduce pneumonia mortality and health inequities.

FUNDING

WHO.

Bloodstream infection among children presenting to a general hospital outpatient clinic in urban Nepal

Background

There are limited data on the etiology and characteristics of bloodstream infections in children presenting in hospital outpatient settings in South Asia. Previous studies in Nepal have highlighted the importance of murine typhus as a cause of febrile illness in adults and enteric fever as a leading bacterial cause of fever among children admitted to hospital.

Methods

We prospectively studied a total of 1084 febrile children aged between 2 months and 14 years presenting to a general hospital outpatient department in Kathmandu Valley, Nepal, over two study periods (summer and winter). Blood from all patients was tested by conventional culture and by real-time PCR for Rickettsia typhi.

Results

Putative etiological agents for fever were identified in 164 (15%) patients. Salmonella enterica serovar Typhi (S. Typhi) was identified in 107 (10%), S. enterica serovar Paratyphi A (S. Paratyphi) in 30 (3%), Streptococcus pneumoniae in 6 (0.6%), S. enterica serovar Typhimurium in 2 (0.2%), Haemophilus influenzae type b in 1 (0.1%), and Escherichia coli in 1 (0.1%) patient. S. Typhi was the most common organism isolated from blood during both summer and winter. Twenty-two (2%) patients were PCR positive for R. typhi. No significant demographic, clinical and laboratory features distinguished culture positive enteric fever and murine typhus.

Conclusions

Salmonella infections are the leading cause of bloodstream infection among pediatric outpatients with fever in Kathmandu Valley. Extension of immunization programs against invasive bacterial disease to include the agents of enteric fever and pneumococcus could improve the health of children in Nepal.