Higher COVID-19 pneumonia risk associated with anti-IFN-α than with anti-IFN-ω auto-Abs in children

We found that 19 (10.4%) of 183 unvaccinated children hospitalized for COVID-19 pneumonia had autoantibodies (auto-Abs) neutralizing type I IFNs (IFN-α2 in 10 patients: IFN-α2 only in three, IFN-α2 plus IFN-ω in five, and IFN-α2, IFN-ω plus IFN-β in two; IFN-ω only in nine patients). Seven children (3.8%) had Abs neutralizing at least 10 ng/ml of one IFN, whereas the other 12 (6.6%) had Abs neutralizing only 100 pg/ml. The auto-Abs neutralized both unglycosylated and glycosylated IFNs. We also detected auto-Abs neutralizing 100 pg/ml IFN-α2 in 4 of 2,267 uninfected children (0.2%) and auto-Abs neutralizing IFN-ω in 45 children (2%). The odds ratios (ORs) for life-threatening COVID-19 pneumonia were, therefore, higher for auto-Abs neutralizing IFN-α2 only (OR [95% CI] = 67.6 [5.7-9,196.6]) than for auto-Abs neutralizing IFN-ω only (OR [95% CI] = 2.6 [1.2-5.3]). ORs were also higher for auto-Abs neutralizing high concentrations (OR [95% CI] = 12.9 [4.6-35.9]) than for those neutralizing low concentrations (OR [95% CI] = 5.5 [3.1-9.6]) of IFN-ω and/or IFN-α2.

The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection fatality rate (IFR) doubles with every 5 y of age from childhood onward. Circulating autoantibodies neutralizing IFN-α, IFN-ω, and/or IFN-β are found in ∼20% of deceased patients across age groups, and in ∼1% of individuals aged <70 y and in >4% of those >70 y old in the general population. With a sample of 1,261 unvaccinated deceased patients and 34,159 individuals of the general population sampled before the pandemic, we estimated both IFR and relative risk of death (RRD) across age groups for individuals carrying autoantibodies neutralizing type I IFNs, relative to noncarriers. The RRD associated with any combination of autoantibodies was higher in subjects under 70 y old. For autoantibodies neutralizing IFN-α2 or IFN-ω, the RRDs were 17.0 (95% CI: 11.7 to 24.7) and 5.8 (4.5 to 7.4) for individuals <70 y and ≥70 y old, respectively, whereas, for autoantibodies neutralizing both molecules, the RRDs were 188.3 (44.8 to 774.4) and 7.2 (5.0 to 10.3), respectively. In contrast, IFRs increased with age, ranging from 0.17% (0.12 to 0.31) for individuals <40 y old to 26.7% (20.3 to 35.2) for those ≥80 y old for autoantibodies neutralizing IFN-α2 or IFN-ω, and from 0.84% (0.31 to 8.28) to 40.5% (27.82 to 61.20) for autoantibodies neutralizing both. Autoantibodies against type I IFNs increase IFRs, and are associated with high RRDs, especially when neutralizing both IFN-α2 and IFN-ω. Remarkably, IFRs increase with age, whereas RRDs decrease with age. Autoimmunity to type I IFNs is a strong and common predictor of COVID-19 death.

Autoantibodies neutralizing type I IFNs are present in 4% of uninfected individuals over 70 years old and account for 20% of COVID-19 deaths

Circulating autoantibodies (auto-Abs) neutralizing high concentrations (10 ng/mL, in plasma diluted 1 to 10) of IFN-α and/or -ω are found in about 10% of patients with critical COVID-19 pneumonia, but not in subjects with asymptomatic infections. We detect auto-Abs neutralizing 100-fold lower, more physiological, concentrations of IFN-α and/or -ω (100 pg/mL, in 1/10 dilutions of plasma) in 13.6% of 3,595 patients with critical COVID-19, including 21% of 374 patients > 80 years, and 6.5% of 522 patients with severe COVID-19. These antibodies are also detected in 18% of the 1,124 deceased patients (aged 20 days-99 years; mean: 70 years). Moreover, another 1.3% of patients with critical COVID-19 and 0.9% of the deceased patients have auto-Abs neutralizing high concentrations of IFN-β. We also show, in a sample of 34,159 uninfected subjects from the general population, that auto-Abs neutralizing high concentrations of IFN-α and/or -ω are present in 0.18% of individuals between 18 and 69 years, 1.1% between 70 and 79 years, and 3.4% >80 years. Moreover, the proportion of subjects carrying auto-Abs neutralizing lower concentrations is greater in a subsample of 10,778 uninfected individuals: 1% of individuals <70 years, 2.3% between 70 and 80 years, and 6.3% >80 years. By contrast, auto-Abs neutralizing IFN-β do not become more frequent with age. Auto-Abs neutralizing type I IFNs predate SARS-CoV-2 infection and sharply increase in prevalence after the age of 70 years. They account for about 20% of both critical COVID-19 cases in the over-80s, and total fatal COVID-19 cases.

[Genetic predisposition to mucocutaneous fungal infections]

Mucocutaneous fungal infections are common and usually occur in the presence of certain risk factors. However, these infections can occur in patients with no known risk factors. This indicates the presence of an underlying genetic susceptibility to fungi reflecting an innate or adaptive immune deficiency. In this review, we highlight genetic factors that predispose to mucocutaneous fungal infections specially candidiasis and dermatophytosis.

Research of anti-GAD and anti-IA2 autoantibodies by ELISA test in a series of Moroccan pediatric patients with diabetes type 1

Introduction

Type I diabetes (T1D) is an autoimmune disease with a prediabetic, asymptomatic period characterized by the selective destruction of insulin-producing β cells. During the pre-clinical phase, various auto-antibodies are generated against several beta cell antigens such as anti glutamate acid decarboxylase (Anti-GAD), anti tyrosine phosphatase (Anti-IA2). Today, the coupled detection of Anti-IA2 with that of Anti-GAD proves its great importance in the diagnosis and prediction of type 1 diabetes. The combined positivity for both antibodies has a specificity and a positive predictive value of 100%.

Objectives

In this work, we evaluate the diagnostic value of anti-GAD and anti-IA2 antibodies in a series based on 78 Moroccan subjects initially under 16, suspected T1D.

Results and Discussion

Our series consists mainly of 74% of newly diagnosed patients for T1D and 26% of confirmed diagnostic patients, of whom 52% are females. The mean age of diagnosis is 7 ± 4 years, the mean of HbA1c at the time of diagnosis is 11.63 ± 2.16%, and the percentage of family history in our series is 69%. The proportion of positive results for anti-IA2 antibodies and anti-GAD antibodies are, respectively, 76.92% and 62.82%, and 52.56% of patients are positive for both auto-antibodies. This study confirms that anti-GAD and anti-IA2 auto-antibodies assays can detect patients early and the autoantibodies can persist several years after diagnosis of type 1 diabetes.

Conclusion

This study confirmed the diagnosis and classification of T1D (type 1A) in 87.18% of patients, and we reported that the prevalence of anti-GAD and anti-IA2 is higher in girls than in boys.

[Chronic mucocutaneous candidiasis with STAT1 gain-of-function mutation associated with herpes virus and mycobacterial infections]

INTRODUCTION

Chronic mucocutaneous candidiasis (CMC) is characterized by susceptibility to chronic or recurrent infections with yeasts of the genus Candida affecting the skin, nails and mucous membranes. We describe a Moroccan patient presenting CMC with heterozygous STAT1 gain-of-function (GOF) mutation.

PATIENTS AND METHODS

A 5-year-old boy with no consanguinity presented recurrent episodes of oral thrush, chronic nail candidiasis and herpetic gingivostomatitis from the age of 8 months. He also had mycobacterial adenitis secondary to BCG vaccination and atypical rosacea. Genetic analysis revealed GOF mutation of the STAT1 gene.

DISCUSSION

CMC was diagnosed in our patient despite poor clinical features. Sequencing of the genome revealed STAT1GOF mutation. This mutation affects production of IL-17, an important cytokine in mucocutaneous defense against Candida. The association with mycobacterial adenitis is rare and continues to be poorly understood. The presence of atypical rosacea in this setting is suggestive of this entity. Antifungal therapy and prevention of complications are necessary to reduce the morbidity and mortality associated with this condition.

CONCLUSION

CMC due to STAT1GOF mutation is characterized by a broad clinical spectrum and should be considered in all cases of chronic or recurrent fungal infection, whether or not associated with other infections.

Utility of the QuantiFERON-TB Gold In-Tube assay for the diagnosis of tuberculosis in Moroccan children

SETTING

The utility of interferon-gamma release assays (IGRAs), such as the QuantiFERON-TB Gold In-Tube (QFT-GIT) test, in diagnosing active tuberculosis (TB) in children is unclear and depends on the epidemiological setting.

OBJECTIVE

To evaluate the performance of QFT-GIT for TB diagnosis in children living in Morocco, an intermediate TB incidence country with high bacille Calmette-Gurin vaccination coverage.

DESIGN

We prospectively recruited 109 Moroccan children hospitalised for clinically suspected TB, all of whom were tested using QFT-GIT.

RESULTS

For 81 of the 109 children, the final diagnosis was TB. The remaining 28 children did not have TB. QFT-GIT had a sensitivity of 66% (95%CI 5277) for the diagnosis of TB, and a specificity of 100% (95%CI 88100). The tuberculin skin test (TST) had lower sensitivity, at 46% (95%CI 3360), and its concordance with QFT-GIT was limited (69%). Combining QFT-GIT and TST results increased sensitivity to 83% (95%CI 6992).

CONCLUSION

In epidemiological settings such as those found in Morocco, QFT-GIT is more sensitive than the TST for active TB diagnosis in children. Combining the TST and QFT-GIT would be useful for the diagnosis of active TB in children, in combination with clinical, radiological and laboratory data.

Emerging Infections and Pertinent Infections Related to Travel for Patients with Primary Immunodeficiencies

In today's global economy and affordable vacation travel, it is increasingly important that visitors to another country and their physician be familiar with emerging infections, infections unique to a specific geographic region, and risks related to the process of travel. This is never more important than for patients with primary immunodeficiency disorders (PIDD). A recent review addressing common causes of fever in travelers provides important information for the general population Thwaites and Day (N Engl J Med 376:548-560, 2017). This review covers critical infectious and management concerns specifically related to travel for patients with PIDD. This review will discuss the context of the changing landscape of infections, highlight specific infections of concern, and profile distinct infection phenotypes in patients who are immune compromised. The organization of this review will address the environment driving emerging infections and several concerns unique to patients with PIDD. The first section addresses general considerations, the second section profiles specific infections organized according to mechanism of transmission, and the third section focuses on unique phenotypes and unique susceptibilities in patients with PIDDs. This review does not address most parasitic diseases. Reference tables provide easily accessible information on a broader range of infections than is described in the text.

Pott's disease in Moroccan children: clinical features and investigation of the interleukin-12/interferon-γ pathway

SETTING

Tuberculosis spondylodiscitis (TS), or Pott's disease, an extra-pulmonary form of tuberculosis (TB), is rare and difficult to diagnose in children. Some cases of severe TB in children were recently explained by inborn errors of immunity affecting the interleukin-12/interferon-gamma (IL-12/IFN-γ) axis.

OBJECTIVE

To analyse clinical data on Moroccan children with TS, and to perform immunological and genetic explorations of the IL-12/IFN-γ axis.

DESIGN

We studied nine children with TS diagnosed between 2012 and 2014. We investigated the IL-12/IFN-γ circuit by both whole-blood assays and sequencing of the coding regions of 14 core genes of this pathway.

RESULTS

A diagnosis of TS was based on a combination of clinical, biological, histological and radiological data. QuantiFERON(®)-TB Gold In-Tube results were positive in 75% of patients. Whole-blood assays showed normal IL-12 and IFN-γ production in all but one patient, who displayed impaired decreased response to IL-12. No candidate disease-causing mutations were detected in the exonic regions of the 14 genes.

CONCLUSIONS

TS diagnosis in children remains challenging, and is based largely on imaging. Further investigations of TS in children are required to determine the role of genetic defects in pathways that may or may not be related to the IL-12/IFN-γ axis.

[BCGitis/BCGosis in children: Diagnosis, classification and exploration]

The Bacille Calmette-Guérin (BCG) vaccine is used extensively worldwide, and more than 100 million children are vaccinated each year. This is a live vaccine that protects against severe tuberculosis in children. However, BCG complications, specific to the BCG vaccine, do occur, although the epidemiology differs from one country to another. Nevertheless, these complications are considered to be rare and range from benign local BCGitis to BCGosis, a potentially lethal disseminated disease. Etiologies of BCGitis/BCGosis can be related to the vaccine itself (technical errors, vaccinal strain) or to the patient. Indeed, it is well established that some immunodeficiencies, primary or acquired, can expose the patient to BCG disease. The diagnosis of a BCG disease lies on clinical examination and laboratory results. Recent advances in molecular biology help to distinguish BCG disease from other mycobacterial infections, especially from tuberculosis. When BCG complications have been confirmed, the underlying defect should be investigated, particularly if other features of immunodeficiency are reported, such as recurrent infection, failure to thrive, etc. Prognosis largely depends on the immune status, but also on the management of the BCG disease. Although the therapeutic protocols are still controversial, there are more and more publications on the diagnosis and management guidelines of the disease.

[Purulent pericarditis and colonic infiltrating to Salmonella enteritidis complicated by acute intussusception in a case of IL-12Rβ1 deficiency]

IL-12 receptor β1 deficiency (IL-12Rβ1) predisposes patients to mycobacteria and Salmonella infections. We report a case of IL-12Rβ1 deficiency with a fatal multi-resistant Salmonella enteritidis infection. This boy was born after from a consanguineous marriage, and diagnosed as having a IL-12Rβ1 deficiency since the age of 3 months. He presented with recurrent Salmonella enteritidis essentially digestive localization, complicated by purulent pericarditis at the same germ at the age of two and a half years. At the age of 3, a colonic infiltration due to a Salmonella enteritidis resistant to antibiotics, was complicated by acute intussusception, and the child died. The IL-12Rβ1 deficiency is considered as having a good prognosis, in contrast to what happened in our patient. We review therapeutic issues in these patients.

First report on the Moroccan registry of primary immunodeficiencies: 15 years of experience (1998-2012)

PURPOSE

Primary immunodeficiencies (PIDs) are a large group of diseases characterized by susceptibility to infections. We provide the first comprehensive report on PIDs in Morocco, the epidemiological, clinical, etiological and outcome features which have never before been described.

METHODS

A national registry was established in 2008, grouping together data for PID patients diagnosed since 1998.

RESULTS

In total, 421 patients were diagnosed between 1998 and 2012. Parental consanguinity was common (recorded for 43.2 % of patients) and the median time to diagnosis was 2.0 years. Overall, 27.4 % of patients were considered to have well defined syndromes with immunodeficiency (48 cases of hyper-IgE syndrome and 40 of ataxia-telangiectasia); 22.7 % had predominantly antibody deficiencies (29 cases of agammaglobulinemia and 24 of CVID); 20.6 % had combined immunodeficiencies (37 cases of SCID and 26 of MHC II deficiencies) and 17.5 % had phagocyte disorders (14 cases of SCN and 10 of CGD). The principal clinical signs were lower respiratory tract infections (60.8 %), skin infections (33.5 %) and candidiasis (26.1 %). Mortality reached 28.8 %, and only ten patients underwent bone marrow transplantation. We analyzed the impact on mortality of residence, family history, parental consanguinity, date of diagnosis and time to diagnosis, but only date of diagnosis had a significant effect.

CONCLUSIONS

The observed prevalence of PID was 0.81/100,000 inhabitants, suggesting considerable underdiagnosis and a need to increase awareness of these conditions in Morocco. The distribution of PIDs was different from that reported in Western countries, with a particularly high proportion of SCID, MHC II deficiencies, hyper-IgE syndrome and autosomal recessive agammaglobulinemia. However, we have now organized a national network, which should improve diagnosis rates in remote regions.

Molecular defects in Moroccan patients with ataxia-telangiectasia

Ataxia-telangiectasia (AT) is a rare autosomal recessive disease, affecting neurologic and immune system. Numerous mutations are described in the ATM gene in several populations. However, in Morocco, few data are available concerning this condition. Our main goal is to determine clinical, immunological, and molecular presentation of Moroccan patients with AT. We screened 27 patients, out of 22 unrelated families, for ATM gene mutations. All our patients showed ataxia, ocular telangiectasia, and immunodeficiency, as well as elevated serum alphafetoprotein levels. Mean age at diagnosis was 5.51 years, and consanguinity rate was 81.8 %. Mean age at onset was 2.02 years, and mean time to diagnosis was 3.68 years. We found 14 different mutations in 19 unrelated families, of which 7 were not reported. Our results showed that c.5644C>T mutation was the most common in our series. However, further studies are required to demonstrate a founder effects on ATM gene in Moroccan patients, who showed mutational heterogeneity otherwise. Our data indicate that direct sequencing of coding exons is sufficient for a high detection rate in ATM in Moroccan population.

Intermittent chronic neutropenia in a patient with familial Mediterranean fever

A 12-year-old daughter of consanguineous Moroccan parents was diagnosed with cyclic neutropenia, based on a combination of recurrent gingivostomatitis, a fluctuating neutrophil count, and several episodes of severe neutropenia. No ELA2 gene mutations were found. At age 19 years she presented with edema of the limbs, proteinuria and renal failure. Renal amyloidosis AA was diagnosed by biopsy. Gene mutations associated with family Mediterranean fever (FMF) were sought, and a homozygous mutation (M694V) was found in the MFEV gene. This is the novel finding of FMF that masqueraded as cyclic neutropenia.

[Forty-one pediatric cases of non-typhoidal salmonellosis]

Non-typhoidal Salmonella (NTS) infections are a major cause of infantile death in developing countries.

OBJECTIVE

The aim of this study was to determine the epidemiologic and therapeutic data, as well as the evolution of NTS in Morocco.

METHOD

This retrospective study was made on 41 patients hospitalized for NTS between 1994 and 2002 in the Casablanca University Hospital Pediatric ward.

RESULTS

Twenty cases of digestive salmonellosis were diagnosed, 16 cases of septicemia, and 10 cases of meningitis. Ten patients were hospitalized after an outbreak of resistant Salmonella typhimurium in a nursery. Fifty percent of the patients were less than 3 months of age. The three patients between 1 and 3 years of age presented with primary immunodeficiency. Fever, vomiting, and diarrhea were noted in 97% of the cases. The stools were watery in 89% and severe dehydration in 55% of the cases. Salmonella strains were identified in blood in 25 cases, from stools in 10 cases, and from CSF in nine cases. The following Salmonella serotypes were identified: S. typhimurium (53.6%), S. enteritidis (44%), and S. agona (2.4%). Resistance to antibiotics was noted, especially for Salmonella typhimurium (34%) in the nursery outbreak. The evolution was favorable in 80%, but two children with meningitis developed severe neurological sequels, and six hypotrophic infants under 3 years of age died after septicemia.