Primary Immunodeficiency Diseases and Bacillus Calmette-Guérin (BCG)-Vaccine-Derived Complications: A Systematic Review

Rare Biallelic Variants Affecting the Interdomain B Region of Zeta-Chain Associated Protein Kinase 70 (ZAP70) Protein in a Sudanese Patient: Case Report

Introduction

A class of disorders known as inborn errors of immunity (IEI) is defined by a compromised or missing immune response, which increases the vulnerability to infections, immunological dysregulation, and cancer. Severe combined immunodeficiencies (SCIDs), affecting both T and B-cell function are rare but often severe diseases. In this report, we describe a 10-month-old SCID patient from Sudan with disseminated BCG infection.

Case Presentation

A 10-month-old boy whose parents were first degree relatives, presented with a six-month history of repeated chest infections and fever. Physical examination revealed a very ill-looking boy with respiratory distress dependent on oxygen, had slight abdominal distention and hepatomegaly. Investigations revealed positive polymerase chain reaction (PCR) for M. tuberculosis complex infection and low CD4+ and CD8+ cells. Genetic testing showed compound heterozygosity in trans for two variants in the Zeta-chain Associated Protein Kinase 70 (ZAP70) gene associated with autosomal recessive SCID. The patient was started on BCG-related infection treatment, intravenous immunoglobulin (IVIG) replacement and trimethoprim/sulfamethoxazole prophylaxis with an excellent response and the patient responded well to the treatment.

Conclusion

SCIDs are rare, and early management is crucial. In this case, a diagnosis of ZAP70 deficiency was based on next-generation sequencing and inhouse bioinformatic computational analysis of the ZAP70 gene, highlighting the importance of genetic testing in the workup of immunodeficiencies in low resource settings.

Tuberculosis and Bacillus Calmette-Guérin Disease in Patients with Chronic Granulomatous Disease: an Experience from a Tertiary Care Center in North India

Chronic granulomatous disease (CGD) is a phagocytic defect characterized by recurrent bacterial and fungal infections. We report clinical profile of patients with CGD and mycobacterial infections in a cohort from North India. A review of clinical and laboratory records was carried out for patients with CGD registered at our center between 1990 and 2021. Of the 99 patients with CGD, 22 had mycobacterial infections-Mycobacterium tuberculosis and M. bovis-BCG in 11 each. Among the children with M. bovis-BCG infection, 6 had localized and 5 had disseminated BCG disease. Median age at onset of symptoms and diagnosis of BCG disease was 5 months and 15 months, respectively. While disseminated forms of BCG were noted only in CYBB defect, none of the patients with NCF1 defect developed complications due to BCG vaccine. A recurring radiological feature was left axillary lymph node calcification, which was present in around 50% of CGD patients with BCG infections. Of 11 patients with tuberculosis, pulmonary, pleuro-pulmonary, abdominal, and disseminated forms were present in 6, 1, 2, and 2, respectively. Median age at onset of symptoms and diagnosis of tuberculosis was 129 months and 130 months, respectively. Molecular defects were identified in CYBB (5), NCF1 (4), and CYBA (1). Incidence of tuberculosis and BCG-related complications in patients with CGD is higher than the normal population. Screening for CGD is warranted in any patient with adverse reactions to BCG vaccination, calcification of left axillary lymph node, and persistent, recurrent or disseminated forms of tuberculosis.

Nature and nurture: understanding phenotypic variation in inborn errors of immunity

The overall disease burden of pediatric infection is high, with widely varying clinical outcomes including death. Among the most vulnerable children, those with inborn errors of immunity, reduced penetrance and variable expressivity are common but poorly understood. There are several genetic mechanisms that influence phenotypic variation in inborn errors of immunity, as well as a body of knowledge on environmental influences and specific pathogen triggers. Critically, recent advances are illuminating novel nuances for fundamental concepts on disease penetrance, as well as raising new areas of inquiry. The last few decades have seen the identification of almost 500 causes of inborn errors of immunity, as well as major advancements in our ability to characterize somatic events, the microbiome, and genotypes across large populations. The progress has not been linear, and yet, these developments have accumulated into an enhanced ability to diagnose and treat inborn errors of immunity, in some cases with precision therapy. Nonetheless, many questions remain regarding the genetic and environmental contributions to phenotypic variation both within and among families. The purpose of this review is to provide an updated summary of key concepts in genetic and environmental contributions to phenotypic variation within inborn errors of immunity, conceptualized as including dynamic, reciprocal interplay among factors unfolding across the key dimension of time. The associated findings, potential gaps, and implications for research are discussed in turn for each major influencing factor. The substantial challenge ahead will be to organize and integrate information in such a way that accommodates the heterogeneity within inborn errors of immunity to arrive at a more comprehensive and accurate understanding of how the immune system operates in health and disease. And, crucially, to translate this understanding into improved patient care for the millions at risk for serious infection and other immune-related morbidity.

Inborn errors of immunity in mainland China: the past, present and future

Inborn errors of immunity (IEI), also known as primary immunodeficiency diseases, comprise a group of rare genetic disorders that affect the development or/and function of the immune system. These disorders predispose individuals to recurrent infections, autoimmunity, cancer and immune dysregulations. The field of IEI diagnosis and treatment in mainland China has made significant strides in recent years due to advances in genome sequencing, genetics, immunology and treatment strategies. However, the accessibility and affordability of diagnostic facilities and precision treatments remain variable among different regions. With the increasing government emphasis on rare disease prevention, diagnosis, and treatment, the field of IEI is expected to progress further in mainland China. Herein, we reviewed the development and current state of IEI in mainland China, highlighting the achievements made, as well as opportunities and challenges that lie ahead.

Clinical and Genetic Characteristics of BCG Disease in Chinese Children: a Retrospective Study

PURPOSE

Summarize the characteristics of a large cohort of BCG disease and compare differences in clinical characteristics and outcomes among different genotypes and between primary immunodeficiency disease (PID) and patients without identified genetic etiology.

METHODS

We collected information on patients with BCG disease in our center from January 2015 to December 2020 and divided them into four groups: chronic granulomatous disease (CGD), Mendelian susceptibility to mycobacterial disease (MSMD), severe combined immunodeficiency disease (SCID), and gene negative group.

RESULTS

A total of 134 patients were reviewed, and most of them had PID. A total of 111 (82.8%) patients had 18 different types of pathogenic gene mutations, most of whom (91.0%) were classified with CGD, MSMD, and SCID. CYBB was the most common gene mutation (52/111). BCG disease behaves differently in individuals with different PIDs. Significant differences in sex (P < 0.001), age at diagnosis (P = 0.013), frequency of recurrent fever (P = 0.007), and vaccination-homolateral axillary lymph node enlargement (P = 0.039) and infection severity (P = 0.006) were noted among the four groups. The CGD group had the highest rate of males and the oldest age at diagnosis. The MSMD group had the highest probability of disseminated infection (48.3%). The course of anti-tuberculosis treatment and the survival time between patients with PID and without identified genetic etiology were similar.

CONCLUSION

Greater than 80% of BCG patients have PID; accordingly, gene sequencing should be performed in patients with BCG disease for early diagnosis. BCG disease behaves differently in patients with different types of PID. Patients without identified genetic etiology had similar outcomes to PID patients, which hints that they may have pathogenic gene mutations that need to be discovered.

Recurrent or unusual infections in children - when to worry about inborn errors of immunity

Recurrent infections are a common presenting feature in paediatrics and, while most times considered part of normal growing up, they are also a classical hallmark of inborn errors of immunity (IEI). We aimed to outline the value of currently used signs for IEI and the influence of the changing epidemiology of infectious diseases due to implementation of new vaccines and the effect of the COVID-19 pandemic on the assessment of children with recurrent infections. Warning signs for IEI have been developed, but the supporting evidence for their effectiveness is limited, and immune dysregulation is more commonly recognised as a feature for IEI, making reliable identification of children who should be screened for IEI on clinical grounds difficult. In addition, the epidemiology of infectious diseases is changing due to restrictions related to Covid-19 as well as immunisations, which may change the threshold to screen children for IEI. Treatments for IEI are evolving and are often more effective and less complicated when started early. Screening for IEI can be initiated by the non-immunologist and should be considered early to ensure optimal treatment outcomes.

The Middle East and North Africa Diagnosis and Management Guidelines for Inborn Errors of Immunity

Human inborn errors of immunity (IEI) are a group of 485 distinct genetic disorders affecting children and adults. Signs and symptoms of IEI are heterogeneous, and accurate diagnosis can be challenging and depends on the available human expertise and laboratory resources. The Middle East and North Africa (MENA) region has an increased prevalence of IEI because of the high rate of consanguinity with a predominance of autosomal recessive disorders. This area also exhibits more severe disease phenotypes compared with other regions, probably due to the delay in diagnosis. The MENA-IEI registry network has designed protocols and guidelines for the diagnosis and treatment of IEI, taking into consideration the variable regional expertise and resources. These guidelines are primarily meant to improve the care of patients within the region, but can also be followed in other regions with similar patient populations.

Primary immunodeficiencies (PID) Life Index in Southeast Asia: A comparative analysis of PID Principles of Care (PoC)

Objective

To analyze the implementation of the Principles of Care (PoC) in primary immunodeficiencies (PID) in Southeast Asia (SEA) countries - six years after its call of action.

Methodology

Using the newly developed PID Life Index software, the index of implementation of principles of care in the management of PIDs patients involving the six participating SEA countries (Cambodia, Indonesia, Malaysia, Vietnam, Thailand, and Philippines) were extracted. For each of the six separate principles, the index from the six countries will be compared and presented based on the calculated index.

Results

Comparative analysis of the six principles of care of PID in the SEA countries showed low diagnostic rate with minimal availability of diagnostic tests options. Generally, almost all SEA countries provide curative treatments, vaccines, and anti-infectious therapies although the reimbursement scheme varied in relieving patients' financial burden. We also highlighted the active involvement of patient organizations in SEA, with main areas of work focused on advocacy and increasing awareness among public and healthcare professionals.

Discussion and conclusion

It is applaudable that the SEA continent is gradually strengthening its work in management of PID, especially in Thailand and Vietnam. However, more emphasis must be placed among stakeholders in SEA countries towards successful implementation of the PoC for a holistic management of PID patients.

Personalized predictions of adverse side effects of the COVID-19 vaccines

Background

Misconceptions about adverse side effects are thought to influence public acceptance of the Coronavirus disease 2019 (COVID-19) vaccines negatively. To address such perceived disadvantages of vaccines, a novel machine learning (ML) approach was designed to generate personalized predictions of the most common adverse side effects following injection of six different COVID-19 vaccines based on personal and health-related characteristics.

Methods

Prospective data of adverse side effects following COVID-19 vaccination in 19943 participants from Iran and Switzerland was utilized. Six vaccines were studied: The AZD1222, Sputnik V, BBIBP-CorV, COVAXIN, BNT162b2, and the mRNA-1273 vaccine. The eight side effects were considered as the model output: fever, fatigue, headache, nausea, chills, joint pain, muscle pain, and injection site reactions. The total input parameters for the first and second dose predictions were 46 and 54 features, respectively, including age, gender, lifestyle variables, and medical history. The performances of multiple ML models were compared using Area Under the Receiver Operating Characteristic Curve (ROC-AUC).

Results

The total number of people receiving the first dose of the AZD1222, Sputnik V, BBIBP-CorV, COVAXIN, BNT162b2, and mRNA-1273 were 6022, 7290, 5279, 802, 277, and 273, respectively. For the second dose, the numbers were 2851, 5587, 3841, 599, 242 and 228. The Logistic Regression model for predicting different side effects of the first dose achieved ROC-AUCs of 0.620-0.686, 0.685-0.716, 0.632-0.727, 0.527-0.598, 0.548-0.655, 0.545-0.712 for the AZD1222, Sputnik V, BBIBP-CorV, COVAXIN, BNT162b2 and mRNA-1273 vaccines, respectively. The second dose models yielded ROC-AUCs of 0.777-0.867, 0.795-0.848, 0.857-0.906, 0.788-0.875, 0.683-0.850, and 0.486-0.680, respectively.

Conclusions

Using a large cohort of recipients vaccinated with COVID-19 vaccines, a novel and personalized strategy was established to predict the occurrence of the most common adverse side effects with high accuracy. This technique can serve as a tool to inform COVID-19 vaccine selection and generate personalized factsheets to curb concerns about adverse side effects.

BCG Vaccine-associated Complications in a Large Cohort of Children With Combined Immunodeficiencies Affecting Cellular and Humoral Immunity

AIMS

To present the details of Bacillus Calmette-Guérin (BCG)-vaccine associated complications (VACs) in combined immunodeficiencies (CID) patients.

METHODS

Five centers participated in this retrospective study and completed a data form, which included general patients' information, clinical and laboratory data.

RESULTS

Among 236 CID patients, 127 were BCG vaccinated. 41.9% of patients with family history of CID and 17.1% who were diagnosed by screening were BCG vaccinated. Twenty-three patients (18.1%) developed BCG-VACs. The median age of VACs was 6 months and the median time from vaccination to complications was 6 months. The highest rate of BCG-VACs was recorded in patients receiving the Russian BCG strain compared to the Tokyo and Danish strains. Univariate analysis of T-lymphocyte subsets showed increased odds of BCG complications in patients with CD3+, CD4+, and CD8+ counts of ≤250 cells/µL. Only CD8 + count ≤250 cells/µL had increased such odds on multivariate analysis. VACs were disseminated in 13 and localized in 10 patients. Localized complication occurred earlier after vaccination (median: 4 months) compared with disseminated ones (median: 7 months). There were no significant associations between sex, administered vaccine strain, serum immunoglobulins levels, lymphocyte subsets counts, and the chance of having either localized or disseminated BCG-related complications.

COCLUSIONS

Although contraindicated, many patients with CID continue to be vaccinated with BCG. Low CD8 + count is a risk factor for BCG-related complications and localized complications occurred earlier than disseminated ones. Considerations should be undertaken by health care authorities especially in countries with high incidence of CID to implement newborn screening, delay the time of BCG vaccine administration beyond 6 months of age and to use the relatively safer strains like the Danish and Tokyo ones.

Candidate genes and sequence variants for susceptibility to mycobacterial infection identified by whole-exome sequencing

Inborn errors of immunity are known to influence susceptibility to mycobacterial infections. The aim of this study was to characterize the genetic profile of nine patients with mycobacterial infections (eight with BCGitis and one with disseminated tuberculosis) from the Republic of Moldova using whole-exome sequencing. In total, 12 variants in eight genes known to be associated with Mendelian Susceptibility to Mycobacterial Disease (MSMD) were detected in six out of nine patients examined. In particular, a novel splice site mutation c.373–2A>C in STAT1 gene was found and functionally confirmed in a patient with disseminated tuberculosis. Trio analysis was possible for seven out of nine patients, and resulted in 23 candidate variants in 15 novel genes. Four of these genes - GBP2, HEATR3, PPP1R9B and KDM6A were further prioritized, considering their elevated expression in immune-related tissues. Compound heterozygosity was found in GBP2 in a single patient, comprising a maternally inherited missense variant c.412G>A/p.(Ala138Thr) predicted to be deleterious and a paternally inherited intronic mutation c.1149+14T>C. Functional studies demonstrated that the intronic mutation affects splicing and the level of transcript. Finally, we analyzed pathogenicity of variant combinations in gene pairs and identified five patients with putative oligogenic inheritance. In summary, our study expands the spectrum of genetic variation contributing to susceptibility to mycobacterial infections in children and provides insight into the complex/oligogenic disease-causing mode.

Neonatal Bacillus Calmette-Guérin Vaccination to Prevent Early-Life Eczema: A Systematic Review and Meta-analysis

ABSTRACT

Increasing evidence suggests that early-life bacillus Calmette-Guérin (BCG) vaccine could prevent atopic eczema through its beneficial off-target effects. In this meta-analysis, 3 randomized control trials with similar methods were included and enabled robust estimations with low heterogeneity, involving a total of 5655 children randomized to early-life BCG Denmark (n = 2832) or no BCG (n = 2823). Meta-analyses suggest a beneficial effect of BCG to prevent eczema (risk ratio [RR], 0.89; 95% confidence interval [CI], 0.82-0.98). In subgroup analyses, BCG was more beneficial in boys (RR, 0.84; 95% CI, 0.74-0.95) and in children born to 2 atopic parents (RR, 0.81; 95% CI, 0.68-0.97). The NNT to prevent one case of eczema among children of 1 or 2 atopic parent was 20 (95% CI, 12-50). Bacillus Calmette-Guérin Denmark leads to an 11% reduction in the risk of eczema in early life. A greater effect was observed with increasing predisposition. Given its well-established safety profile, neonatal BCG vaccination should be considered for children of atopic parents.

Three novel homozygous ITGB2 mutations among two patients with leukocyte adhesion defect type-1: Two case reports

BACKGROUND

A leukocyte adhesion defect (LAD) is a rare primary immunodeficiency disorder. LAD type 1 (LAD-1) is the most common, which is caused by ITGB2 mutation resulting in dysfunction of β2 integrin, which impairs leukocyte adherence to the endothelium.

CASE SUMMARY

The first two cases of LAD-1 in Thailand presented with recurrent omphalitis, soft tissue infection, marked leukocytosis, and neutrophilia. One patient experienced delayed umbilical cord separation. Mutation analysis was performed by direct DNA sequencing of the ITGB2 gene. The results revealed two novel homozygous missense mutations, c.920C>T (p.Leu307Pro) in exon 8 and c.758G>A (p.Arg253His) in exon 7, and one novel homozygous nonsense mutation, c.262C>T (p.Gln88Ter) in exon 4, in the genomic DNA of the first and second patients, respectively. Heterozygous mutations were identified in the parents of both patients, suggesting a carrier status. The patients were administered intravenous antibiotics for infections with good clinical responses. Hematopoietic stem cell transplantation could not be performed due to the unavailability of matched donors. However, a significant decline in infections was observed after antibiotic prophylaxis. Several follow-up visits were conducted for both patients. They are currently 6 years old.

CONCLUSION

Molecular analysis is essential for definitive diagnosis, early treatment implementation, and prevention of LAD-1 in future pregnancy.

Inborn Errors of Immunity in Patients with Adverse Events Following BCG Vaccination in Brazil

OBJECTIVE

The Bacille Calmette-Guérin (BCG) vaccine is routinely applied in Brazil. Adverse events (AE) may occur in patients with inborn or acquired immunodeficiencies, varying between local (BCGitis) or disseminated (BCGosis) reactions. We evaluated 53 individuals with local or disseminated adverse events to BCG vaccination to assess if they had inborn errors of immunity (IEI).

METHODS

Patients diagnosed with an adverse event following BCG vaccination between 2014 and 2017 were included in the study. We collected clinical data, immunophenotyped T and B lymphocytes, and natural killer cells (NK), assessed oxidative function of neutrophils through dihydrorhodamine (DHR) 123 testing, and genotyped 361 genes related to IEI through targeted (panel) sequencing.

RESULTS

The median age of the 53 individuals was four months (IQ 1.5-12), and 52.8% were male. Forty-eight (90.6%) individuals presented only locoregional AE and five (9.4%) presented both locoregional and disseminated AE. Nine (16.9%) patients were diagnosed with an IEI. Four of them presented BCGitis and five presented BCGosis after BCG vaccination. Clinically, four presented chronic granulomatous disease (CGD), three Mendelian susceptibility to mycobacterial disease (MSMD), and two severe combined immunodeficiency (SCID). Patients with IEI had a higher frequency of systemic symptomatology (p = 0.002), history of other infections (p < 0.001), parental consanguinity (p = 0.01), familial history of sick siblings (p < 0.001), or early deaths in the family (p < 0.01).

CONCLUSION

There is a high frequency of IEI in patients with locoregional and disseminated adverse events to BCG vaccination, revealing the need for the investigation of IEI accompanied by clinical and familial inquiry.

BCG Infection in Patients With Inborn Errors of Immunity Receiving the Russian BCG Strain

BACKGROUND

Bacillus Calmette-Guierin (BCG) vaccination complications are common in inborn errors of immunity (IEI) due to the inability to clear live attenuated Mycobacterium bovis. Various BCG-vaccine strains are used worldwide, and the profile of the Russian BCG strain vaccine complications in IEI is poorly characterized.

OBJECTIVE

To evaluate risks of BCG infection in a large cohort of patients with IEI vaccinated with the Russian BCG strain.

METHODS

We evaluated 778 patients with IEI vaccinated with the Russian BCG strain.

RESULTS

A total of 114 (15%) developed BCG infection, 41 (36%) with local, 19 (17%) with regional, and 54 with (47%) disseminated disease. BCG infection was seen in 58% of the patients with severe combined immunodeficiency (SCID), 82% with chronic granulomatous disease, 50% with innate immune defects, 5% with combined immunodeficiency, and 2% with other IEI. BCG infection presented at a median age of 4 to 5 months in SCID, chronic granulomatous disease, combined immunodeficiency, and other IEI groups versus 12 months in patients with innate immune defects (P < .005). We found no influence of specific genetic defects, CD3⁺ and natural killer cell numbers in SCID, or dihydrorhodamine test stimulation index values in chronic granulomatous disease on the BCG-infection risks. All patients with SCID received antimycobacterial therapy at SCID diagnosis even in the absence of active BCG infection. More antimycobacterial agents were required in disseminated relative to local or regional infection (P < .0001). Only 1 of 114 patients (with SCID) died of BCG-related complications (<1%).

CONCLUSIONS

BCG infection is common in patients with IEI receiving BCG vaccination. Rational early antimycobacterial therapy, combined with anticytokine agents for posttransplant inflammatory syndrome prevention, and treatment in SCID may prevent BCG-related mortality.

Antimycobacterial prophylaxis regarding Bacillus Calmette-Guérin -associated complications in children with primary immunodeficiency

OBJECTIVE

Bacillus Calmette-Guérin (BCG) vaccine derived from Mycobacterium bovis can cause BCG vaccine associated complications (BCG-VAC) especially in patients with primary immunodeficiencies (PID). No consensus exists for antimycobacterial prophylactic therapy for patients with PID who receive the BCG vaccine.

AIM

This study aimed to define the risk factors in the development of BCG-VAC and effect of antimycobacterial prophylaxis in PID patients vaccinated with BCG.

METHODS

This is a retrospective cohort study. 104 patients diagnosed with PID who received the BCG vaccination were referred to pediatric pulmonology in a single center were enrolled. The demographic characteristics, type, dosage and duration of antimycobacterial prophylaxis regimen, treatment modalities for BCG-VAC were documented. Regression analysis was performed to evaluate the effect of covariates for predicting BCG-VAC in patients with PIDs.

RESULTS

Among 104 patients 21 (21.2%) developed BCG-VAC. The frequency of BCG-VAC was highest in patients with Mendelian susceptibility to mycobacterial disease (46.2%) followed by patients with severe combined immunodeficiency (22.4%) and those with chronic granulomatous disease (9.5%). Prophylactic therapy against mycobacterium was initiated for 72 patients (69.2%). Among patients who received the antimycobacterial prophylaxis, BCG-VAC developed in only four patients (5.6%), whereas 17 patients (53.1%) developed BCG-VAC in the non-prophylaxis group and this difference was statistically significant (p < 0.001). Multivariable regression analysis with age at diagnosis, type of PID, receiving antimycobacterial prophylaxis, median T cell number at the time of PID diagnosis and HSCT status showed that not receiving antimycobacterial prophylaxis and lower median T cell number were predictors, with antimycobacterial prophylaxis having the highest odds ratio for BCG-VAC prediction in patients with PIDs (p:<0.001, R²:0.64).

CONCLUSION

The lower frequency of BCG-VAC in our cohort can be explained by two main reasons; relatively late BCG vaccination schedule and receiving antimycobacterial prophylaxis. It is reasonable to begin antimycobacterial prophylaxis in patients with PIDs who are susceptible to BCG-VAC.

Recurrent Infections and Immunodeficiency Caused by Severe Pancytopenia Associated with a Novel Life-Threatening Mutation in Hypoxia-Upregulated Protein 1

HYOU1 encodes a protein from the endoplasmic reticulum chaperone proteins, expressed to protect cellular mechanisms from stress such as hypoxia, insufficient energy and excessive or insufficient substances, and to restore cell homeostasis. In this study, we report a novel pathogenic variant in HYOU1. The proband, the second patient with pathogenic variant in HYOU1, was a female born to consanguineous parents. A novel homozygous pathogenic variant in HYOU1 (NM_001130991.3: c.1456C>T; p.Arg486Cys) was identified, causing anemia, thrombocytopenia and severe panleukopenia and immunodeficiency in the second month of age, leading to consistent high-grade fever, regression of brain functions and recurrent infections; ultimately resulting in the patient expiring at three and half months of age. Both parents are heterozygous for this variant and have no issues related to this study.

Activated Phosphoinositide 3-Kinase δ Syndrome: a Large Pediatric Cohort from a Single Center in China

PURPOSE

Activated phosphoinositide 3-kinase δ syndrome (APDS) is a primary immunodeficiency first described in 2013, which is caused by gain-of-function mutations in PIK3CD or PIK3R1, and characterized by recurrent respiratory tract infections, lymphoproliferation, herpesvirus infection, autoimmunity, and enteropathy. We sought to review the clinical phenotypes, immunological characteristics, treatment, and prognosis of APDS in a large genetically defined Chinese pediatric cohort.

METHODS

Clinical records, radiology examinations, and laboratory investigations of 40 APDS patients were reviewed. Patients were contacted via phone call to follow up their current situation.

RESULTS

Sinopulmonary infections and lymphoproliferation were the most common complications in this cohort. Three (10.3%) and five (12.5%) patients suffered localized BCG-induced granulomatous inflammation and tuberculosis infection, respectively. Twenty-seven patients (67.5%) were affected by autoimmunity, while malignancy (7.5%) was relatively rare to be seen. Most patients in our cohort took a combined treatment of anti-infection prophylaxis, immunoglobulin replacement, and immunosuppressive therapy such as glucocorticoid or rapamycin administration. Twelve patients underwent hematopoietic stem cell transplantation (HSCT) and had a satisfying prognosis.

CONCLUSION

Clinical spectrum of APDS is heterogeneous. This cohort's high incidence of localized BCG-induced granulomatous inflammation and tuberculosis indicates Mycobacterial susceptibility in APDS patients. Rapamycin is effective in improving lymphoproliferation and cytopenia. HSCT is an option for those who have severe complications and poor response to other treatments.

It Takes a Village: The Multifaceted Immune Response to Mycobacterium tuberculosis Infection and Vaccine-Induced Immunity

Despite co-evolving with humans for centuries and being intensely studied for decades, the immune correlates of protection against Mycobacterium tuberculosis (Mtb) have yet to be fully defined. This lapse in understanding is a major lag in the pipeline for evaluating and advancing efficacious vaccine candidates. While CD4+ T helper 1 (TH1) pro-inflammatory responses have a significant role in controlling Mtb infection, the historically narrow focus on this cell population may have eclipsed the characterization of other requisite arms of the immune system. Over the last decade, the tuberculosis (TB) research community has intentionally and intensely increased the breadth of investigation of other immune players. Here, we review mechanistic preclinical studies as well as clinical anecdotes that suggest the degree to which different cell types, such as NK cells, CD8+ T cells, γ δ T cells, and B cells, influence infection or disease prevention. Additionally, we categorically outline the observed role each major cell type plays in vaccine-induced immunity, including Mycobacterium bovis bacillus Calmette-Guérin (BCG). Novel vaccine candidates advancing through either the preclinical or clinical pipeline leverage different platforms (e.g., protein + adjuvant, vector-based, nucleic acid-based) to purposefully elicit complex immune responses, and we review those design rationales and results to date. The better we as a community understand the essential composition, magnitude, timing, and trafficking of immune responses against Mtb, the closer we are to reducing the severe disease burden and toll on human health inflicted by TB globally.

The Spectrum of Inborn Errors of Immunity in the United Arab Emirates: 5 Year Experience in a Tertiary Center

Purpose

Inborn Errors of Immunity (IEI) are heterogeneous disorders of immunity with variable clinical presentation and outcome. This is the first comprehensive report from the United Arab Emirates aiming to describe the demographics, clinical characteristics, categories, treatment modalities and outcome of patients with IEI.

Methods

This retrospective study was conducted on patients who attended Tawam Hospital between 2016-2020.

Results

We identified 162 patients with IEI, of whom 152 were children. The age of onset of symptoms ranged between birth to 38 years. About two-thirds of patients were Emirati nationals, 64.2% had consanguineous parents and 38.3% of cases were familial. Patients were classified as; immunodeficiencies affecting cellular and humoral immunity (20.4%), combined immunodeficiencies with associated or syndromic features (38.3%), predominantly antibody deficiencies (16%), immune dysregulation (4.3%), congenital defects of phagocytes number or function (8.6%), defects in intrinsic and innate immunity (1.9%) autoinflammatory disorders (1.9%), complement deficiency (6.2%), bone marrow failure (1.9%) and phenocopies of inborn errors of immunity (0.6%). Genetic testing was performed in 85.2% of patients with a diagnostic yield of 92.7%. Complications included bronchiectasis, neoplasia, and vaccine-related infections. Immunoglobulin therapy and antimicrobial prophylaxis were both used in (51.9%) of patients while (20.4%) underwent hematopoietic stem cell transplantation (HSCT). The overall mortality rate was 10.5%.

Conclusion

This report highlights the burden of IEI in the UAE. Ongoing education of physicians, establishment of a national registry and considering changes to early BCG vaccination are measures recommended to improve outcomes.

Revaccination with Bacille Calmette-Guérin (BCG) is associated with an increased risk of abscess and lymphadenopathy

The reported frequency and types of adverse events following initial vaccination and revaccination with Bacille Calmette-Guérin (BCG) varies worldwide. Using active surveillance in a randomised controlled trial of BCG vaccination (the BRACE trial), we determined the incidence and risk factors for the development of BCG injection site abscess and regional lymphadenopathy. Injection site abscess occurred in 3% of 1387 BCG-vaccinated participants; the majority (34/41, 83%) resolved without treatment. The rate was higher in BCG-revaccinated participants (OR 3.6, 95% CI 1.7-7.5), in whom abscess onset was also earlier (median 16 vs. 27 days, p = 0.008). No participant with an abscess had a positive interferon-gamma release assay. Regional lymphadenopathy occurred in 48/1387 (3%) of BCG-vaccinated participants, with a higher rate in revaccinated participants (OR 2.1, 95% CI 1.1-3.9). BCG-associated lymphadenopathy, but not injection site abscess, was influenced by age and sex. A previous positive tuberculin skin test was not associated with local reactions. The increased risk of injection site abscess or lymphadenopathy following BCG revaccination is relevant to BCG vaccination policy in an era when BCG is increasingly being considered for novel applications.

Study Design for an Evaluation of Newborn Screening for SCID in the UK

Severe combined immunodeficiency is a rare inherited disorder, which, if untreated, invariably proves fatal in late infancy or early childhood. With treatment, the prognosis is much improved. Early treatment of the siblings of cases, before they become symptomatic, has shown considerable improvements in outcomes. Based on this and the development of a test that can be used on the whole population of neonates (measurement of T-cell receptor excision circles-TRECs), many countries have added it to their routine newborn bloodspot screening programmes. The UK National Screening Committee (UKNSC) has considered whether SCID should be added to the UK screening programme and concluded that it was likely to be cost effective, but that there were a number of uncertainties that should be resolved before a national roll-out could be recommended. These include some aspects of the test, such as: cost; the use of different assays and cut-off levels to reduce false positive rates, while maintaining sensitivity; the overall benefits of screening for disease outcome in patients with SCID and other identified disorders; the need for a separate pathway for premature babies; the acceptability of the screening programme to parents of babies who have normal and abnormal (both true and false positive) screening results. To achieve this, screening of two thirds of babies born in England over a two-year period has been planned, beginning in September 2021. The outcomes and costs of care of babies identified by the screening will be compared with those of babies identified with SCID in the rest of the UK. The effect of the screening programme on parents will form part of a separate research project.

BCG Moreau Polish Substrain Infections in Patients With Inborn Errors of Immunity: 40 Years of Experience in the Department of Immunology, Children's Memorial Health Institute, Warsaw

OBJECTIVE

We aimed to assess BCG (Bacillus Calmette-Guérin) complications in patients with Inborn Errors of Immunity (IEI), according to the inherited disorders and associated immunological defects, as well as the different BCG substrains.

MATERIAL

We studied adverse reactions to the locally-produced BCG Moreau vaccine, analyzed in patients with IEI diagnosed between 1980 and 2020 in the Department of Immunology, Children's Memorial Health Institute (CMHI), Warsaw. These results were compared with previously published studies.

RESULTS

Significantly fewer disseminated BCG infections (BCGosis) were found in 11 of 72 (15%) SCID (Severe Combined Immunodeficiency) NK (Natural Killer)-phenotype patients, when compared with the 119 out of 349 (34%) (p = 0.0012) patients with SCID with BCG in other countries. Significantly fewer deaths caused by BCGosis were observed (p = 0.0402). A significantly higher number of hematopoietic stem cell transplantations (HSCTs) were performed in the CMHI study (p = 0.00001). BCGosis was found in six patients with Mendelian susceptibility to mycobacterial diseases (MSMD). Other patients with IEI prone to BCG complications, such as CGD (Chronic Granulomatous Disease), showed no case of BCGosis.

CONCLUSION

The BCG Moreau substrain vaccine, produced in Poland since 1955, showed genetic differences with its parental Brazilian substrain together with a superior clinical safety profile in comparison with the other BCG substrains, with no BCGosis in patients with IEI other than SCID and MSMD. Our data also confirmed significantly fewer cases of BCGosis and deaths caused by BCG infection in patients with SCID with this vaccine substrain. Finally, they confirmed the protecting role of NK cells, probably via their production of IFN-γ.

Differential diagnosis of primary immunodeficiency in patients with BCGitis and BCGosis: A single-centre study

BCG infections occur more frequently in patients with underlying primary immunodeficiency disease (PIDD). In this study, we aimed to evaluate the ratio of PIDD in the patients with BCG infections. Patients with BCG infections were analyzed in a tertiary referral centre in the 2015-2020 period. Forty-seven patients with BCGitis/BCGosis were evaluated; thirty-four (72.3%) had BCGitis, and 13 (27.7%) had BCGosis. Common tissue and organs affected are lymph nodes (57.4%), skin and subcutaneous tissue (48.9%), lungs (23.4%) and liver (17%). PIDD was shown in 26 patients (55.3%), including 92.3% of patients with BCGosis and 41.2% of patients with BCGitis. Ten patients had Mendelian susceptibility to Mycobacterial disease (MSMD) (21.2%), six had predominantly antibody deficiency (PAD) (12.7%), five had severe combined immunodeficiency (SCID) (10.6%), three had CGD (6.3%), and two had CID (4.2%). Mortality was reported in two patients (4.2%) with CID (ZAP70 deficiency (n = 1) and PIK3R1 deficiency (n = 1)). Parental consanguinity (84%), axillary lymphadenopathy (65%), mycobacterial lung disease (42%), hepatomegaly (30%) and growth retardation (19%) were significantly high in patients with PIDD diagnosis. Isolated vaccination site infection was also recorded in patients with PIDD (CID (n = 1), SCID (n = 1), PAD (n = 5)). BCG vaccination should be planned with caution for the cases with suspected PIDD. This study indicates that almost all patients (92.3%) with BCGosis and one in every two patients (41.2%) with BCGitis have an underlying PIDD. Parental consanguinity, axillary lymphadenopathy, mycobacterial lung disease, hepatomegaly and growth retardation (19%) are important clinical features in the differential diagnosis of PIDD.

Management of Bacille Calmette-Guérin Lymphadenitis and Abscess in Immunocompetent Children: A Systematic Review

BACKGROUND

There is no consensus on managing common adverse reactions to Bacille Calmette-Guérin (BCG) vaccination. We systematically reviewed the management of BCG-associated regional lymphadenitis and injection site abscess in immunocompetent individuals.

METHODS

Searches of Medline, Embase and PubMed were done until November 2020. Randomized controlled trials (RCTs) and cohort studies that compared management strategies for complications of intradermal BCG vaccination were included.

RESULTS

Of 1338 individual articles, 15 met inclusion criteria. Six RCTs, 4 prospective and 4 retrospective cohort studies compared management in 1022 children with BCG-associated lymphadenitis. For nonsuppurative lymphadenitis, no antimicrobial was found to significantly impact on time to resolution or prevention of suppuration. For suppurative lymphadenitis, there was some evidence that needle aspiration shortens time to resolution and prevents sinus tract formation. Surgical excision (mainly offered for persistent suppurative lymphadenitis) generally had favorable outcome. Two cohort studies (including 1 aforementioned) compared management strategies in up to 36 children with BCG injection site abscess; one showed no difference in outcome in children treated with antibiotics and the other reported complete resolution without treatment.

CONCLUSIONS

Evidence does not support a role for antimicrobial therapy in the management of localized reactions to BCG vaccination in immunocompetent children. Needle aspiration may shorten the recovery period for BCG-associated suppurative lymphadenitis. BCG injection site abscess usually heals without treatment. However, studies are limited and cases are not well defined. Growing research into novel BCG applications provides opportunities to investigate optimal management strategies for adverse reactions in a prospective manner using active safety surveillance.

Vaccination for Patients with Inborn Errors of Immunity: a Nationwide Survey in Japan

We conducted a nationwide survey of inborn errors of immunity (IEI) in Japan for the second time in 10 years, focusing on protective measures for IEI patients against infectious diseases. Questionnaires were sent to various medical departments nationwide, and a total of 1307 patients were reported. The prevalence of IEI was 2.2 patients per 100,000 population, which was comparable with the previous nationwide study. The most common disease category was autoinflammatory disorders (25%), followed by antibody deficiencies (24%) and congenital defects of phagocyte number or function (16%). We found that a significant number of patients received contraindicated vaccines, principally because the patients were not diagnosed with IEI by the time of the vaccination. Regarding diseases for which BCG vaccination is contraindicated, 43% of patients had actually received BCG, of which 14% developed BCG-related infections. BCG-related infections were mainly observed among patients with CGD and MSMD. In order to prevent IEI patients from receiving inadequate vaccines, continuous education to parents and physicians is needed, along with the expansion of newborn screening, but efforts to screen IEI at the site of vaccination also remain important.

Difficulties in Diagnosing and Treating Disseminated Bacillus Calmette-Guérin (BCG) Infection After Intravesical BCG Therapy in a Patient with Liver Cirrhosis: A Case Report

Patient: Male, 62-year-old

Final Diagnosis: BCGitis

Symptoms: Fever • general fatigue

Medication: —

Clinical Procedure: Bone marrow biopsy • liver biopsy

Specialty: Infectious Diseases • General and Internal Medicine

Case Report: Acquired Disseminated BCG in the Context of a Delayed Immune Reconstitution After Hematological Malignancy

Context

Disseminated infections due to Mycobacterium bovis Bacillus Calmette-Guérin (BCG) are unusual and occur mostly in patients with inborn error of immunity (IEI) or acquired immunodeficiency. However, cases of secondary BCGosis due to intravesical BCG instillation have been described. Herein, we present a case of severe BCGosis occurring in an unusual situation.

Case Description

We report one case of severe disseminated BCG disease occurring after hematological malignancy in a 48-year-old man without BCG instillation and previously vaccinated in infancy with no complication. Laboratory investigations demonstrated that he was not affected by any known or candidate gene of IEI or intrinsic cellular defect involving IFNγ pathway. Whole genome sequencing of the BCG strain showed that it was most closely related to the M. bovis BCG Tice strain, suggesting an unexpected relationship between the secondary immunodeficiency of the patient and the acquired BCG infection.

Conclusion

This case highlights the fact that, in addition to the IEI, physicians, as well as microbiologists and pharmacists should be aware of possible acquired disseminated BCG disease in secondary immunocompromised patients treated in centers that administrate BCG for bladder cancers.

Spectrum of Inborn errors of immunity in a cohort of 90 patients presenting with complications to BCG vaccination in India

World Health Organisation recommends the practice of BCG vaccination at birth in countries which have a high incidence of tuberculosis and/or high leprosy burden. The BCG vaccination is considered safe for a competent immune system. However, in children with weakened immune systems cause of which can be primary or secondary, the vaccine may lead to side effects which can be localized or disseminated. In this study, we report a spectrum of inborn errors of immunity (IEI) commonly referred to as primary immunodeficiency disorders (PIDs) diagnosed in a large cohort of patients presenting with complications to BCG vaccination from India. Retrospective data analysis of patients referred to ICMR- National Institute of Immunohematology (ICMR-NIIH) for IEI workup between 2007 and 2019 was done. IEI was identified in n = 52/90 (57.7%) patients presenting with BCG complications. Of these, n = 13(14.4%) patients were diagnosed with severe combined immune deficiency, n = 15(16.7%) with chronic granulomatous disease, n = 19(21.1%) with Inborn errors of IFN-γ immunity, n = 4(4.4%) with Combined immunodeficiency and n = 1(1.1%) with Leucocyte Adhesion Deficiency type1. Majority of cases with BCGosis (88%) had an underlying IEI. This study strongly highlights the need for evaluation of patients with BCG complications for underlying IEI. While disseminated BCGosis strongly predicts underlying IEI, even localized persistent adenitis may be a warning sign of underlying IEI. It is also strongly recommended to record a family history of previous sibling death prior to administration of this live vaccine and deferring live vaccine till the diagnosis of IEI is ruled out in cases with a positive family history.

Vaccination of immune compromised children-an overview for physicians

Immune compromised children are threatened by a higher risk of infections; some of these are preventable by vaccination. Primary care physicians play a fundamental role in optimising vaccination status. In this narrative review, we present the evidence on vaccine safety and immunogenicity in immune compromised children and discuss in which conditions live-attenuated vaccines can possibly be used. Vaccination schedules differ in some of these conditions, including the use of vaccines with higher antigenic contents (e.g. high-dose hepatitis B vaccine), additional vaccine doses (e.g. 2-dose schedule meningococcal vaccine), more frequent booster doses (e.g. life-long pneumococcal vaccine booster), supplementary vaccines (e.g. meningococcal B vaccine) and use of vaccines beyond the age of usual recommendation (e.g. Haemophilus influenza type b vaccine after 5 years of age). Serological monitoring is a useful tool for customizing vaccination schedule in immune compromised children, confirming adequate vaccine response and documenting seroprotection (especially against measles and varicella). Finally, verification of vaccination status of all household members can prevent them being vector of transmission of an infection to the immune compromised children. Conclusion: Intensified information strategies are needed to improve trust, rectify perceived risks and improve vaccine acceptability; primary physicians can play a critical role in the latter. What is Known: • Physician's awareness is key to success, since it repeatedly correlates with higher vaccination rates What is New: • The vaccination status of immunocompromised children is rarely up-to-date • Knowing the latest vaccine recommendations is challenging, as they differ for each medical condition and change periodically • This review summarises the vaccine recommendations for children with compromised immune systems and highlights how paediatricians play a key role in coordinating their application.

Case Report: A Case of Leukocyte Adhesion Deficiency, Type III Presenting With Impaired Platelet Function, Lymphocytosis and Granulocytosis

Fermitin family homolog 3 (FERMT3), alternatively kindlin-3 (KIND3), is an integrin binding protein (of 667 residues) encoded by the FERMT3 gene. The molecule is essential for activating integrin α_IIbβ₃ (the fibrinogen receptor) on platelets and for the integrin-mediated hematopoietic cell (including platelets, T lymphocytes, B lymphocytes, and granulocytes) adhesion. Its defects are associated with impaired primary hemostasis, described as "Glanzmann's thrombasthenia (MIM#273800)-like bleeding problem." The defects are also associated with infections, designated as "LAD1 (leukocyte adhesion deficiency, type I; MIM#116920)-like immune deficiency." The entity that joins the impaired primary hemostasis with the leukocyte malfunction has been termed "leukocyte adhesion deficiency, type III" (LAD3, autosomal recessive, MIM#612840), representing a defective activation of the integrins β₁, β₂, and β3 on leukocytes and platelets. Here, we report a male toddler with novel compound heterozygous variants, NM_178443.2(FERMT3):c.1800G>A, p.Trp600^* (a non-sense variant) and NM_178443.2(FERMT3):c.2001del p.^*668Glufs^*106 (a non-stop variant). His umbilical cord separated at about 3 weeks of age. A skin rash (mainly petechiae and purpura) and recurrent episodes of severe epistaxis required blood transfusions in early infancy. His hemostatic work-up was remarkable for a normal platelet count, but abnormal platelet function screen with markedly prolonged collagen-epinephrine and collagen-ADP closure times. The impaired platelet function was associated with reduced platelet aggregation with all agonists. The expression of platelet receptors was normal. Other remarkable findings were persistent lymphocytosis and granulocytosis, representing defects in diapedesis due to the integrin dysfunction. The natural history of his condition, structure and sequence analysis of the variations, and comparison with other LAD3 cases reported in the literature are presented.

Case Report: Reactive Lymphohistiocytic Proliferation in Infant With a Novel Nonsense Variant of IL2RG Who Received BCG Vaccine

We present here a male young infant with X-linked severe combined immunodeficiency (MIM#300400) due to the novel nonsense variant of IL2RG (interleukin 2 receptor, gamma; MIM#308380), NM_000206.2(IL2RG):c.820_823dup p.Ser275Asnfs^*29. He developed aggressive reactive lymphohistiocytic proliferation after receiving the live-attenuated Bacillus Calmette-Guérin (BCG) vaccine at birth. This report advocates for modifying the current practice of early use of BCG. The natural history of his disease also suggests considering IL2RG variants as a potential cause of "X-linked recessive Mendelian susceptibility to mycobacterial disease" (MSMD). His reactive lymphohistiocytic proliferation and massive hepatosplenomegaly simulated hemophagocytic lymphohistiocytosis (HLH, likely triggered by the BCG disease). This entity was masked by the absence of fever and markedly elevated inflammatory biomarkers. Thus, his findings stimulate discussion on the need to modify the diagnostic criteria of HLH, in order to accommodate conditions, such IL2RG variants that block systemic inflammation.

[Clinical features of children with immunodeficiency and Mycobacterium tuberculosis infection]

OBJECTIVE

To study the clinical features of Mycobacterium tuberculosis infection in children with secondary immunodeficiency disease (SID) versus primary immunodeficiency disease (PID).

METHODS

A retrospective analysis was performed on the medical data of children with immunodeficiency and Mycobacterium tuberculosis infection (36 children with SID and 52 with PID) and 108 children with Mycobacterium tuberculosis infection but without immunodeficiency (control group).

RESULTS

The onset age in the PID group was significantly lower than those in the control and SID groups (P < 0.05), and the proportation of males in the PID group was significantly higher than those in the control and SID groups (P < 0.05). Compared with the control group, the SID and PID groups had significantly lower incidence rates of tuberculosis poisoning symptoms (night sweeting, weight loss, fatigue and loss of appetite) and positive rate of PPD test (P < 0.05), as well as a significantly higher incidence rate of the involvement of ≥ 3 pulmonary lobes (P < 0.05). The children with PID tended to have the involvement of multiple organs (P < 0.05). The SID group had a significantly higher incidence rate of miliary shadow on chest CT than the control and PID groups (P < 0.05). The PID group had a significantly lower positive rate of IFN-gamma release assay (IGRA) than the control and SID groups (P < 0.05). Mycobacterium tuberculosis infection manifested as latent tuberculosis infection (36.1%) and active tuberculosis (63.9%) in the SID group. The infection mainly manifested as bacille Calmette-Guérin disease in the PID group (90.4%), among whom 2 children (3.8%) also had tuberculosis.

CONCLUSIONS

Children with immunodeficiency and Mycobacterium tuberculosis infection have atypical clinical symptoms, with a high incidence rate of disseminated infection and low positive rates of PPD and IGRA tests, which may lead to misdiagnosis and missed diagnosis. Children with immunodeficiency should undergo regular tuberculosis screening for early identification and intervention.

BCG vaccine: Worrying proposal for COVID-19

Bacille Calmette-Guérin (BCG) vaccine is proven to be effective in protecting against severe tuberculosis. It has been suggested to be able to exert a non-specific beneficial effect as protection against other infectious diseases. The duration of protection against tuberculosis is estimated to be from 10 to 15 years, but the duration of the protection against other infections is not known, maybe up to 20 years, maybe much shorter than that. We don’t know it for sure. BCG induced trained immunity paradigm is based on experimental models, cohort studies with low number of individuals, and some epidemiological data in which other possible interfering factors are not controlled. The titles and scopes of scientific articles should be cautiously considered as they can promote indications of getting vaccinated or revaccinated with BCG, before its effectiveness is confirmed and recommendations are published. Besides, revaccination with BCG can put at serious risk patients with primary or secondary immunodeficiency. Maybe BCG vaccine is effective in preventing COVID-19 deaths or reducing its severity, but may the effect of this vaccine be relevant even with poor health politics and assistance? It is very difficult to compare the epidemiologic data about COVID-19 in different countries. There are countless factors, mainly social and related to the healthcare system, which can be more decisive than the hypothesis of trained immunity induced by BCG. Until now, we can say that BCG’s protective role is, at least, insufficient, given many other factors that corroborate SARS-CoV-2 infection and/or its severity.

Evaluation of patients with primary immunodeficiency associated with Bacille Calmette-Guerin (BCG)-vaccine-derived complications

BACKGROUND

Bacille Calmette-Guerin (BCG) vaccination has a great impact on the prevention of severe complications of tuberculosis. However, in patients with primary immunodeficiencies (PID), it can lead to severe complications such as severe combined immunodeficiency, chronic granulomatous disease, and Mendelian susceptibility to mycobacterial disease. This study highlights the demographics, clinical complications and laboratory parameters among PID patients associated with BCG vaccination side effects.

METHODS

One hundred and thirty-seven PID patients with BCGosis were evaluated in this study, based on the complications following BCG vaccination.

RESULTS

The mean age of the patients with BCG complications at the time of the first visit was five years. The within-group comparison of patients showed a highly significant incidence of pneumonia and hepatomegaly in severe combined immunodeficiency patients. Furthermore, the immunologic data showed an increase in the overall rates of lymphocytes such as CD3+, CD4+ and CD8 + T cells in Mendelian susceptibility to mycobacterial disease patients. The level of immunoglobulins has also increased in chronic granulomatous disease patients.

CONCLUSION

The high rate of undiagnosed PIDs predisposes individuals to a high risk of severe side effects as a result of BCG vaccination, as well as infants that are less than one month of age. Therefore, there is a need for early screening and diagnosis of PIDs before exposing unknown PID status patients to BCG vaccination. The benefits of screening and early diagnosis of PID cannot be overemphasized, especially in patients with a previous family history of immunodeficiency.

Bacillus Calmette-Guerin (BCG) Vaccine-associated Complications in Immunodeficient Patients Following Stem Cell Transplantation

PURPOSE

Bacillus Calmette-Guerin (BCG) is a live attenuated vaccine with the potential of causing severe iatrogenic complications in patients with primary immunodeficiency diseases (PID) before and after hematopoietic stem cell transplantation (HSCT). We aim to investigate risk factors of post-HSCT BCG-related complications in PID patients.

METHODS

A retrospective analysis of pediatric PID patients who had received the BCG vaccine and underwent HSCT at Hadassah-Hebrew University Medical Center, between 2007 and 2019.

RESULTS

We found 15/36 (41.67%) patients who developed post-HSCT BCG-related complications. The most significant risk factor for developing BCG-related complications was T cell deficiency (47.6% of the non-complicated vs 83.3% of the BCGitis and 100% of the BCGosis groups had T cell lymphopenia, p = 0.013). None of the chronic granulomatous patients developed BCG-related manifestation post-transplant. Among T cell-deficient patients, lower NK (127 vs 698 cells/μl, p = 0.04) cell counts and NK-SCID were risk factors for ongoing post-HSCT BCGosis, as was pretransplant disseminated BCGosis (33.3% of patients with BCGosis vs none of the non-BCGosis patients, p = 0.04). Immune reconstitution inflammatory syndrome (IRIS) was observed in 3/5 patients with Omenn syndrome. Prophylactic antimycobacterial treatment was not proven effective.

CONCLUSION

BCG vaccination can cause significant morbidity and mortality in the post-transplant T cell-deficient patient, especially in the presence of pre-transplant disease. Taking a detailed medical history prior to administering, the BCG vaccine is crucial for prevention of this complication.

An Overview of the Development of New Vaccines for Tuberculosis

Currently, there is only one licensed vaccine against tuberculosis (TB), the Bacillus Calmette–Guérin (BCG). Despite its protective efficacy against TB in children, BCG has failed to protect adults against pulmonary TB, lacks therapeutic value, and causes complications in immunocompromised individuals. Furthermore, it compromises the use of antigens present in the purified protein derivate of Mycobacterium tuberculosis in the diagnosis of TB. Many approaches, e.g., whole-cell organisms, subunit, and recombinant vaccines are currently being explored for safer and more efficacious TB vaccines than BCG. These approaches have been successful in developing a large number of vaccine candidates included in the TB vaccine pipeline and are at different stages of clinical trials in humans. This paper discusses current vaccination strategies, provides directions for the possible routes towards the development of new TB vaccines and highlights recent findings. The efforts for improved TB vaccines may lead to new licensed vaccines capable of replacing/supplementing BCG and conferring therapeutic value in patients with active/latent TB.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that can explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents some concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to vaccine injury compensation programs. The majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that might explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents several concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. Given these inadequacies in the evaluation of multifactorial diseases, the WHO guidelines need to be reevaluated and revised. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.