Invasive Pneumococcal Disease in UK Children <1 Year of Age in the Post-13-Valent Pneumococcal Conjugate Vaccine Era: What Are the Risks Now?

Risk of invasive pneumococcal disease during pregnancy and postpartum and association with adverse maternal and foetal outcomes: A prospective cohort study, England, 2014-19

BACKGROUND

Pneumococcal infections are associated with significant morbidity and mortality, especially at the extremes of age and in those with underlying conditions. Little is known about the risks, presentations or outcomes of invasive pneumococcal disease (IPD) during pregnancy or the postpartum period.

METHODS

The UK Health Security Agency conducts enhanced national surveillance of IPD in England. We used national surveillance data to calculate IPD risk and outcomes in pregnant, postpartum and non-pregnant women of childbearing age with IPD over a five-year period in England.

FINDINGS

There were 1701 IPD cases in women aged 15-44 years between 1 July 2014 and 30 June 2019, including 123 (7.2%) pregnant, 38 (2.2%) postpartum and 1540 (90.5%) non-pregnant women. IPD incidence in pregnant women (0.048/1000 woman-years) was not significantly different compared to non-pregnant women (0.041/1000 woman-years; Incidence Rate Ratio [IRR]: 1.17; 95%CI 0.96-1.40; p=0.11). When stratified by trimester, however, women in their third trimester had a 2.27-fold (95%CI 1.80-2.85, p<0.001) increased risk of IPD, compared to non-pregnant women (IRR 2.27, 95%CI 1.78-2.85, p<0.001), while those in the first (IRR 0.49, 95%CI 0.28-0.80) and second trimester (IRR 0.71, 95%CI 0.47-1.04) had a lower risk, albeit only statistically significant for the first trimester. Postpartum women (0.144 per 1000 woman-years), on the other hand, had a 3.49-fold (95%CI 2.46-4.81, p<0.001) higher IPD risk than non-pregnant women. Most pregnant women developed IPD during their third trimester (80/123, 65.0%), with all but one pregnancy resulting in a live birth. IPD in the second trimester was associated with live birth in 77.8% of cases (21/27), while 22.2% experienced a miscarriage (5/27, 18.5%) or stillbirth (1/27, 3.7%). IPD in the first trimester was associated with live birth in 41.7% of cases (5/12), miscarriages in 41.7% (5/12), and termination in 16.7% (2/12) cases. Only three neonates (3/142) had confirmed IPD. There were no deaths in pregnant women with IPD compared to 5.5% (85/1540) in non-pregnant women.

INTERPRETATION

While pregnant women overall did not appear to have an increased risk of IPD compared to non-pregnant women, those infected in third trimester or postpartum appeared to have more than twice the incidence. Most pregnant and postpartum women had a live birth, and subsequent neonatal infection was rare, occurring in 2% of live births.

Safety of a 4-Dose 20-Valent Pneumococcal Conjugate Vaccine Series in Infants: A Randomized Trial

BACKGROUND AND OBJECTIVES

The 20-valent pneumococcal conjugate vaccine (PCV20) was developed to expand protection for pneumococcal disease. It contains all 13-valent pneumococcal conjugate vaccine (PCV13) components plus conjugates for 7 additional serotypes. Our primary objective with this study was to evaluate PCV20 tolerability and safety.

METHODS

In this phase 3, multi-country, double-blind study, healthy infants born at ≥34 weeks' gestation were randomly assigned 2:1 to receive PCV20 or PCV13 at 2, 4, 6, and 12 to 15 months of age. Safety assessments included local reactions and systemic events within 7 days after each vaccination, adverse events (AEs) from dose 1 to 1 month after dose 3 and from dose 4 to 1 month after dose 4, and serious AEs and newly diagnosed chronic medical conditions from dose 1 through 6 months after the last dose.

RESULTS

Participants received PCV20 (N = 1000) or PCV13 (N = 504); 91.7% received all 4 doses. The frequencies of local reactions and systemic events were generally similar in PCV20 and PCV13 groups, with most reported as mild or moderate. The most common local reaction was injection site pain (PCV20, 24.7% to 40.5%; PCV13, 26.8% to 42.0%); irritability was the most common systemic event (PCV20, 54.8% to 68.2%; PCV13, 54.7% to 68.5%). AE frequencies were similar in both groups. No serious AEs were related to study vaccines. Few newly diagnosed chronic medical conditions were reported (2.8% in both groups). PCV20 was safe across multiple countries, in late preterm infants, and when administered with other vaccines.

CONCLUSIONS

A 4-dose series of PCV20 had a tolerability and safety profile similar to that of PCV13.

Risk of Invasive Meningococcal Disease in Preterm Infants

Background

Invasive meningococcal disease (IMD) is most common in the first year of life. We hypothesized that preterm infants may have a higher risk of IMD and more severe disease than term infants. We compared the incidence, demographics, clinical presentation, and outcomes of IMD in preterm compared with term infants during the first 5 years after implementation of a national meningococcal group B vaccine (4CMenB) for infants in England.

Methods

The UK Health Security Agency conducts enhanced national IMD surveillance with detailed follow-up of all confirmed cases in England. Infants aged <1 year (uncorrected for gestational age) with IMD confirmed between 1 September 2015 and 31 August 2020 were included.

Results

There were 393 infant IMD cases (incidence, 12.4/100 000 live births). Among 363 (92.4%) of the infants with known gestational age, the IMD incidence was higher in preterm (<37 weeks' gestation) than in term infants (18.3/100 000 vs 10.9/100 000; incidence rate ratio [IRR], 1.68 [95% confidence interval, 1.23-2.29]; P = .001). The IMD incidence was highest in those born at <32 weeks' gestation (32.9/100 000; incidence rate ratio for <32 weeks' gestation vs term, 3.01 [95% confidence interval, 1.73-5.24]; P ≤ .001). There were no differences in demographics, clinical presentation, rate of intensive care admission, or case-fatality rate, but preterm infants were more likely than term infants to have ≥1 reported sequela (14 of 39 [35.9%] vs 51 of 268 [19.0%]; P = .02).

Conclusions

Preterm infants had a higher incidence of IMD than term infants and the IMD incidence was highest in infants born at <32 weeks' gestation. Preterm infants also had a higher risk of IMD sequelae.

PCV15, a pneumococcal conjugate vaccine, for the prevention of invasive pneumococcal disease in infants and children

INTRODUCTION

Streptococcus pneumoniae is a causative agent of pneumonia and acute otitis media (AOM), as well as invasive diseases such as meningitis and bacteremia. PCV15 (V114) is a new 15-valent pneumococcal conjugate vaccine (PCV) approved for use in individuals ≥6 weeks of age for the prevention of pneumonia, AOM, and invasive pneumococcal disease.

AREAS COVERED

This review summarizes the V114 Phase 3 development program leading to approval in infants and children, including pivotal studies, interchangeability and catch-up vaccination studies, and studies in at-risk populations. An integrated safety summary is presented in addition to immunogenicity and concomitant use of V114 with other routine pediatric vaccines.

EXPERT OPINION

Across the development program, V114 demonstrated a safety profile that is comparable to PCV13 in infants and children. Immunogenicity of V114 is comparable to PCV13 for all shared serotypes except serotype 3, where V114 demonstrated superior immunogenicity. Higher immune responses were demonstrated for V114 serotypes 22F and 33F. Results of the ongoing study to evaluate V114 efficacy against vaccine-type pneumococcal AOM and anticipated real-world evidence studies will support assessment of vaccine effectiveness and impact, with an additional question of whether higher serotype 3 immunogenicity translates to better protection against serotype 3 pneumococcal disease.

Safety and Immunogenicity of V114 in Preterm Infants: A Pooled Analysis of Four Phase Three Studies

BACKGROUND

Risk of invasive pneumococcal disease is 3-fold higher in preterm versus full-term infants. V114 is a 15-valent pneumococcal conjugate vaccine (PCV) containing the 13 serotypes in PCV13 plus 2 unique serotypes, 22F and 33F. A pooled subgroup analysis was performed in preterm infants (<37 weeks gestational age) enrolled in 4 pediatric phase 3 studies evaluating the safety and immunogenicity of different 4-dose regimens of V114 or PCV13.

METHODS

Healthy preterm infants were randomized 1:1 to receive V114/PCV13 in the 4 studies. Safety was evaluated as the proportion of participants with adverse events (AEs) following receipt of PCV. Serotype-specific antipneumococcal immunoglobulin G (IgG) geometric mean concentrations, IgG response rates and opsonophagocytic activity geometric mean titers were measured at 30 days postdose 3, pretoddler dose and 30 days postdose 4.

RESULTS

V114 and PCV13 were administered to 174 and 180 participants, respectively. Mean gestational age was 35.4 weeks (range: 27 - <37 weeks). Proportions of participants with AEs were comparable between vaccination groups; most AEs experienced were of short duration (≤3 days) and mild-to-moderate intensity. V114-elicited IgG geometric mean concentrations, IgG response rates and opsonophagocytic activity geometric mean titers were generally comparable to PCV13 for the 13 shared serotypes and higher for serotypes 22F and 33F at 30 days postdose 3 and postdose 4.

CONCLUSIONS

In preterm infants, V114 was well tolerated and induced comparable immune responses to PCV13 for the 13 shared serotypes and higher immune responses to serotypes 22F and 33F. Results support the use of V114 in preterm infants.

Estimating the Cost-Effectiveness of Switching to Higher-Valency Pediatric Pneumococcal Conjugate Vaccines in the United Kingdom

Currently, the 13-valent pneumococcal conjugate vaccine (PCV13) is administered under a 1+1 (1 primary dose) pediatric schedule in the United Kingdom (UK). Higher-valency PCVs, 15-valent PCV (PCV15), or 20-valent PCV (PCV20) might be considered to expand serotype coverage. We evaluated the cost-effectiveness of PCV20 or PCV15 using either a 2+1 (2 primary doses) or 1+1 schedule for pediatric immunization in the UK. Using a dynamic transmission model, we simulated future disease incidence and costs under PCV13 1+1, PCV20 2+1, PCV20 1+1, PCV15 2+1, and PCV15 1+1 schedules from the UK National Health Service perspective. We prospectively estimated disease cases, direct costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio. Scenario analyses were performed to estimate the impact of model assumptions and parameter uncertainty. Over a five-year period, PCV20 2+1 averted the most disease cases and gained the most additional QALYs. PCV20 2+1 and 1+1 were dominant (cost-saving and more QALYs gained) compared with PCV15 (2+1 or 1+1) and PCV13 1+1. PCV20 2+1 was cost-effective (GBP 8110/QALY) compared with PCV20 1+1. PCV20 was found cost-saving compared with PCV13 1+1, and PCV20 2+1 was cost-effective compared with PCV20 1+1. Policymakers should consider the reduction in disease cases with PCV20, which may offset vaccination costs.

Incidence of pneumococcal disease from 2003 to 2019 in children ≤17 years in England

BACKGROUND

Pneumococcal disease is a leading cause of communicable disease morbidity and mortality globally. We aimed to estimate invasive pneumococcal disease (IPD), pneumococcal pneumonia (PP) and all-cause pneumonia (ACP) incidence rates (IRs) in children aged 0-17 years in England from 2003 to 2019.

METHODS

A retrospective study in children ≤17 years old from 2003 to 2019 using the Clinical Practice Research Datalink (CPRD) Gold and Hospital Episodes Statistics Admitted Patient Care (HES APC) databases. IPD episodes were identified in hospital records (HES APC). PP (caused by Streptococcus pneumoniae only) and ACP episodes (caused by any pathogen) were identified in primary care (CPRD) and in hospital records (HES APC). Annual IRs by age-group were calculated as the number of episodes/person-years (PY) at risk, with 95% confidence intervals (95% CI). Interrupted time series analyses were conducted to assess changes in IRs across the post-PCV7 (2007-2009), early post-PCV13 (2011-2014) and late post-PCV13 (2015-2019) periods compared to the pre-PCV7 period (2003-2005) using generalized linear models.

RESULTS

170 IPD episodes, 769 PP episodes and 12,142 ACP episodes were identified in 1,500,686 children in 2003-2019. The overall IPD, PP and ACP IRs (per 100,000 PY) were 2.29 (95% CI 1.96-2.66), 10.34 (95% CI 9.62-11.10) and 163.37 (95% CI 160.47-166.30), respectively. The highest IPD, PP and ACP IRs were observed in children aged < 2 years compared to older children (2-4 and 5-17 years). IPD IRs decreased between the pre-PCV7 period and the late post-PCV13 period from 3.28 (95% CI 2.42-4.33) to 1.41 (95% CI 0.80-2.29), IRR 0.28 (95% CI 0.09-0.90), p-value 0.033. PP IRs declined between the pre-PCV7 period and the late post-PCV13 period from 14.65 (95% CI 12.77-16.72) to 3.87 (95% CI 2.81-5.20), IRR 0.19 (95% CI 0.09-0.38), p-value < 0.001. ACP IRs declined between the pre-PCV7 period and the late post-PCV13 period from 167.28 (95% CI 160.78-173.96) to 124.96 (95% CI 118.54-131.63), IRR 0.77 (95% CI 0.66-0.88), p-value < 0.001.

CONCLUSIONS

The clinical burden of IPD, PP and ACP declined in children in England aged 0-17 years between 2003 and 2019, especially in the late post-PCV13 period. This study highlights the importance of PCV vaccination in reducing the burden of PD and ACP in children in England.

Screening for Immunodeficiencies in Children With Invasive Pneumococcal Disease: Six-year Experience From a UK Children's Hospital

BACKGROUND

A previous study showed that investigation of children with invasive pneumococcal disease (IPD) revealed an immunodeficiency in up to 10% of cases. Following this report, we implemented a protocol to investigate children with IPD, to assess the proportion with an immunodeficiency in our setting.

METHODS

We retrospectively identified patients who presented with IPD from January 2015 to November 2020 and collected data from medical records. Immunological investigations included complement C3 and C4 levels, classical and alternative pathway complement function, IgG, IgA and IgM levels, specific IgG levels (H. influenza B, tetanus and pneumococcal serotypes), peripheral blood film, lymphocyte subsets, and CD62L-shedding upon activation with Toll-like receptor-agonists in selected cases.

RESULTS

We identified a total of 68 children with IPD, with a mortality of 6%. Immunological investigations were performed in 51 children. Four children (8%) had abnormal findings that were deemed of clinical significance. Two children had complement deficiencies (Factor I and C2 deficiency), one child had specific antibody deficiency, and another child had low IgM, low NK-cells and poor persistence of serotype-specific anti-pneumococcal IgG concentrations. Of the 17 children with IPD who were not tested for immunodeficiencies, 4 died and four had possible explanations for the infection.

CONCLUSIONS

We identified clinically relevant abnormal immunological findings in 4/51 (8%) of children with IPD. Our results support the recommendation to perform immunological investigations in children with IPD, since this might reveal underlying immunodeficiencies, allowing for necessary preventive measures and close follow-up.

The impact of the pneumococcal conjugate vaccines on the incidence of community-acquired alveolar pneumonia in premature compared with in term-born infants

BACKGROUND

Preterm-born children are prone to respiratory infections and complications during infancy and early childhood. In Israel, pneumococcal conjugated vaccines (PCVs) were introduced in 2009-2010, with high vaccination coverage. We assessed the impact of PCV implementation on community-acquired alveolar pneumonia (CAAP) in children < 2 years old born prematurely, in comparison with term born infants.

METHODS

We conducted a prospective, active, population-based surveillance of children < 2 years old with radiologically-proven CAAP, visiting the only regional medical center. CAAP incidence in the pre-PCV and post-PCV eras were compared in early premature (29-32 weeks gestational age [WGA]), late premature (33-36 WGA) and term-born infants (>36 WGA).

RESULTS

Of 214,947 births during the study period, 6'791 CAAP episodes were diagnosed; 211, 653 and 5,806 were in early premature, late premature and term infants, respectively. After PCV implementation, overall CAAP visits were reduced by 44% (95% CI 36-51): 60%, 21% and 45% among those born early preterm, late preterm and at term, respectively (statistically significant for children born early preterm and at term). For outpatients, the respective rate reductions were 79%, 40% and 65% (statistically significant for the children born at term). Importantly, the mean annual rates in the post-PCV period became similar in all 3 groups. The rate reductions among the hospitalized children were lower those that among the non-hospitalized children, with reductions of 56%, 16% and 33% for the three groups, respectively (statistically significant for early preterm and at term children).

CONCLUSIONS

CAAP reduction trends after PCV implementation for preterm-born infants were similar to those for term-born infants. Whether this was because of similar direct PCV- protection, because of indirect (herd) protection or both, is unclear. Post-PCV implementation, the gaps in CAAP rates between infants born prematurely and at term were reduced.

Vaccination rates and adherence in premature infants before and after pneumococcal conjugate vaccine schedule change for term infants - A claims database analysis in Germany

BACKGROUND

In 2015, the German Standing Committee on Vaccination (STIKO) changed the pneumococcal conjugate vaccination (PCV) schedule for mature infants from a 3+1scheme (2, 3, 4, and 11-14 months of age) to a 2+1scheme (2, 4, and 11-14 months of age). For premature infants, the 3+1scheme remained. The aim of this study was to assess vaccination rates, completeness, and timeliness for PCV in premature infants before and after the modified recommendation.

METHODS

A retrospective claims data analysis using the "Institut für angewandte Gesundheitsforschung Berlin" Research Database was conducted. Premature infants born in 2013 and 2016 with an individual follow-up of 24 months were included. Hexavalent combination (HEXA) vaccination with a consistent 3+1recommendation for mature and premature infants was analyzed as reference vaccination.

RESULTS

After 24 months, the PCV rate for at least one dose remained stable in premature newborns of 2016 compared to 2013, while the HEXA vaccination rate increased slightly. However, a significant decrease of a completed PCV schedule (4 doses) in premature infants was noted, whereas the completeness of HEXA vaccination did not change. The timeliness of PCV in premature newborns increased for the first and the booster PCV, while the timeliness of HEXA immunization did not change from 2013 to 2016.

CONCLUSION

Although STIKO still recommends a 3+1PCV schedule for premature infants in Germany, premature infants were vaccinated according to the changed recommendations for mature born infants. A substantial share of premature infants remained unvaccinated, and their vaccinations were often delayed.

Retrospective analysis of neonatal deaths secondary to infections in England and Wales, 2013-2015

OBJECTIVE

To estimate the overall and infection-related neonatal mortality rate and the pathogens responsible using electronic death registrations.

DESIGN

Retrospective analysis of national electronic death registrations data.

SETTING

England and Wales.

PATIENTS

Neonates aged <28 days.

MAIN OUTCOME MEASURES

Overall and infection-related mortality rate per 1000 live births in term, preterm (28-36 weeks) and extremely preterm (<28 weeks) neonates; the contribution of infections and specific pathogens; comparison with mortality rates in 2003-2005.

RESULTS

The neonatal mortality rate during 2013-2015 (2.4/1000 live births; 5095 deaths) was 31% lower than in 2003-2005 (3.5/1000; 6700 deaths). Infection-related neonatal mortality rate in 2013-2015 (0.32/1000; n=669) was 20% lower compared with 2003-2015 (0.40/1000; n=768), respectively. Infections were responsible for 13.1% (669/5095) of neonatal deaths during 2013-2015 and 11.5% (768/6700) during 2003-2005. Of the infection-related deaths, 44.2% (296/669) were in term, 19.9% (133/669) preterm and 35.9% (240/669) extremely preterm neonates. Compared with term infants (0.15/1000 live births), infection-related mortality rate was 5.9-fold (95% CI 4.7 to 7.2) higher in preterm (0.90/1000) and 188-fold (95% CI 157 to 223) higher in extremely preterm infants (28.7/1000) during 2013-2015. A pathogen was recorded in 448 (67%) registrations: 400 (89.3%) were bacterial, 37 (8.3%) viral and 11 (2.4%) fungal. Group B streptococcus (GBS) was reported in 30.4% (49/161) of records that specified a bacterial infection and 7.3% (49/669) of infection-related deaths.

CONCLUSIONS

Overall and infection-related neonatal mortality rates have declined, but the contribution of infection and of specific pathogens has not changed. Further preventive measures, including antenatal GBS vaccine may be required to prevent the single most common cause of infection-related deaths in neonates.

Immunization in the Neonatal Intensive Care Unit

Premature infants admitted to the neonatal intensive care unit are at risk for severe infections and infectious complications caused by vaccine-preventable diseases. Both maternal and neonatal vaccination prevent such infections and improve outcomes for premature infants. An understanding of vaccine efficacy, safety, and administration recommendations, as well as reasons for vaccine hesitancy among clinicians and caregivers, facilitate strategies for improving vaccination rates for infants in the neonatal intensive care unit. Timely vaccination of premature infants confers important protection and improves vaccination rates during childhood.

Immune Response of Indian Preterm Infants to Pentavalent Vaccine Varies With Component Antigens and Gestational Age

Childhood vaccination plays critical role in protecting infants from several dreaded diseases. Of the global 15 million preterm (PT) infants with compromised immune system born annually, India contributes to >3.5 million. Generation of adequate vaccine-induced immune response needs to be ensured of their protection. Immune response of Indian PT (n = 113) and full-term (FT, n = 80) infants to pentavalent vaccine administered as per the national recommendation was studied. Antibody titers against component antigens of pentavalent vaccine, immune cells profiling (T and B cells, monocytes and dendritic cells) and plasma cytokines were determined pre- and post-vaccination. Additionally, cell-mediated recall immune responses to pentavalent antigens were evaluated after short time antigenic exposure to infant PBMCs. Irrespective of gestational age (GA), all the infants developed adequate antibody response against tetanus, diphtheria, and protective but lower antibody levels for Haemophilus influenzae type-b and hepatitis B in preterm infants. Lower (~74%) protective antibody response to pertussis was independent of gestational age. PT-infants exhibited lower frequencies of CD4 T cells/dendritic cells/monocytes, increased plasma IL-10 levels and lower proliferation of central and effector memory T cells than in term-infants. Proliferative central memory response of FT-infants without anti-pertussis antibodies suggests protection from subsequent infection. Responder/non-responder PT-infants lacked immunological memory and could be infected with Bordetella. For hepatitis B, the recall response was gestational age-dependent and antibody status-independent. Humoral/cellular immune responses of PT-infants were dependent on the type of the immunogen. Preterm infants born before 32 weeks of gestation may need an extra dose of pentavalent vaccine for long lived robust immune response.

New insights into the pathogenesis of Streptococcus pneumoniae-associated hemolytic uremic syndrome

The purpose of this review is to describe Streptococcus pneumoniae-associated hemolytic uremic syndrome (P-HUS) with emphasis on new insights into the pathophysiology and management over the past 10 years. Even though awareness of this clinico-pathological entity has increased, it likely remains under-recognized. Recent observations indicate that although neuraminidase activity and exposure of the T-antigen are necessary for development of P-HUS, they are not sufficient; activation of the alternate pathway of complement may also contribute. It is unclear, however, whether or not eculizumab and/or plasmapheresis are of value.

Serotype distribution and antimicrobial resistance patterns of invasive pneumococcal disease isolates from children in mainland China-a systematic review

OBJECTIVES

This study aimed to review and report the serotype distribution and antimicrobial resistance patterns of invasive pneumococcal disease (IPD) isolates, as this information is important for policy making since China has not adopted any pneumococcal vaccines in the national immunization schedule.

METHODS

A systematic review of the published literature from January 2000 to December 2018 was performed to identify articles that describe the serotype and/or antimicrobial resistance patterns of IPD cases in children in mainland China. Analysis of the extracted data was performed with the Microsoft Excel spreadsheet program. The percentage of the serotypes was calculated by dividing the number of isolates for each serotype with the total number of isolates included in all the studies. The theoretical impact of the vaccine was estimated by calculating the percentage of isolates that exhibited the serotypes included in the vaccines. The prevalence of antimicrobial resistance was defined as the number of isolates that were resistant divided by the total number of isolates tested for resistance to the specific antimicrobial agent.

RESULTS

Forty-two articles were screened in the preliminary search, of which sixteen fulfilled inclusion criteria and were included in the final analysis. The predominant serotypes were 19A, 19F, 14, 23F, and 6B, and the estimated impact of PCV13 was 90.4%. The isolates exhibited a high frequency of resistance to cefuroxime, cefaclor, and erythromycin.

CONCLUSIONS

It is necessary for Chinese children to receive PCV13. Clinical workers should pay attention to the high frequency of resistance to antimicrobial agents.

Prevalence of Immunodeficiency in Children With Invasive Pneumococcal Disease in the Pneumococcal Vaccine Era: A Systematic Review

IMPORTANCE

Despite increasing access to vaccination, invasive pneumococcal disease (IPD) is responsible for approximately 826 000 deaths worldwide in children younger than 5 years each year. To allow early identification and prevention, an improved understanding of risk factors for IPD is needed.

OBJECTIVES

To review the literature on the prevalence of primary immunodeficiency (PID) in children younger than 18 years presenting with IPD without another predisposing condition and to inform guidelines for immunologic evaluation after the first episode of IPD based on published evidence.

EVIDENCE REVIEW

A literature search of PubMed, Embase (inception [1974] to February 28, 2019), and MEDLINE (inception [1946] to February 28, 2019) was conducted using the terms Streptococcus pneumonia, Streptococcus pneumoniae, pneumococcal infection, Streptococcus infection, pneumococcal meningitis, immunodeficiency, immune response, immunocompromised, susceptib*, precursor, predispose*, recurren*, newborn, neonat*, infan*, toddler, child, preschooler, adolescen*, and pediatric. Publications reporting original data on immunodeficiency in children with microbiologically confirmed primary or recurrent IPD were included. Strength of clinical data was graded according to the 5-point scale of the Oxford Centre for Evidence-Based Medicine.

FINDINGS

In 6022 unique children with primary IPD, 5 of 393 (1.3%) to 17 of 162 (10.5%) of all children and 14 of 53 (26.4%) of those older than 2 years had a PID identified. Higher rates of PID, up to 10 of 15 (66.7%), were found in children with recurrent IPD. Antibody deficiency was the most common immunodeficiency, followed by complement deficiency, asplenia, and rarer defects in T-cell signaling. The site of infection was a key indicator for the risk of underlying PID, with the greatest risk of PID in children with meningitis or complicated pneumonia.

CONCLUSIONS AND RELEVANCE

Results of this study suggest that invasive pneumococcal disease, and particularly recurrent IPD, is an important marker of underlying PID in children without other risk factors. The findings also suggest that children older than 2 years with pneumococcal meningitis or complicated pneumonia and all children with recurrent IPD should be referred for an immune evaluation.

TRIAL REGISTRATION

PROSPERO identifier: CRD42017075978.