Manish Butte

Rev Chil Pediatr. 2020 Dec;91(6):908-916. doi: 10.32641/rchped.vi91i6.2580. Epub 2020 Oct 21.

ABSTRACT

INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease.

OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID.

PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/μL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality.

RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center.

DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.

PMID:33861827 | DOI:10.32641/rchped.vi91i6.2580

J Clin Immunol. 2021 Apr 14. doi: 10.1007/s10875-021-01035-1. Online ahead of print.

ABSTRACT

PURPOSE: IKAROS, encoded by IKZF1, is a member of the IKAROS family of zinc-finger transcription factors playing critical roles in lymphocyte development, differentiation, and tumor suppression. Several studies demonstrated that IKZF1 mutations affecting DNA binding or homo-/hetero-dimerization are mostly associated with common variable immunodeficiency, combined immunodeficiency, or hematologic manifestations. Herein we report a likely de novo, nonsense IKZF1 mutation (p.C182*) in a baby with low T cell receptor excision circles (TREC) identified by newborn screening testing for severe combined immunodeficiency. The patient also presented a profound B cell deficiency at birth.

METHODS: Genetic, functional, immunologic, and clinical outcome data associated with this patient and her mutation were evaluated.

RESULTS: Mutant p.C182* was detected in the cytoplasm of the patient’s primary cells, in contrast to wild type (WT) IKAROS protein, only detected in the nucleus. Functional in vitro assessments revealed that p.C182* was less stable than WT IKAROS protein and failed to bind to its target DNA binding sequence and dimerize with WT IKAROS protein, resulting in impaired pericentromeric targeting and transcriptional repression by means of haploinsufficiency. During follow-up, while a spontaneous recovery of TREC and T cells was observed, B cells improved but not to sustained normal ranges.

CONCLUSIONS: Patients with IKAROS-associated diseases can present with SCID-like TREC values through newborn screening testing. IKZF1 mutations should be added to the low TREC differential, although spontaneous recovery has to be considered.

PMID:33855675 | DOI:10.1007/s10875-021-01035-1

Front Immunol. 2021 Mar 29;12:663883. doi: 10.3389/fimmu.2021.663883. eCollection 2021.

ABSTRACT

Chronic granulomatous disease (CGD) is a primary immunodeficiency, which is diagnosed in most patients between one and three years of age. Here we report on a boy who presented at birth with extensive skin lesions and lymphadenopathy which were caused by CGD. An analysis of the literature revealed 24 patients with CGD who became symptomatic during the first six weeks of life. Although pulmonary complications and skin lesions due to infection were the leading symptoms, clinical features were extremely heterogenous. As follow-up was not well specified in most patients, the long-term prognosis of children with very early onset of CGD remains unknown.

PMID:33854515 | PMC:PMC8039294 | DOI:10.3389/fimmu.2021.663883

Open Med (Wars). 2021 Apr 1;16(1):532-539. doi: 10.1515/med-2021-0256. eCollection 2021.

ABSTRACT

BACKGROUND: Good’s syndrome (GS) is an immunodeficiency disease, causing thymoma, low or absent B-cells, hypogammaglobulinemia, and defects in cell-mediated immunity. The most common clinical presentation is recurrent infection, followed by refractory diarrhea, due to the immunodeficiency. However, there are only few reports on intestinal endoscopy and pathology.

CASE SUMMARY: We report here two typical GS cases with diarrhea as the prominent manifestation. Both cases presented with thymoma combined with immunodeficiency, characterized by hypogammaglobulinemia, low or absent B lymphocytes, and decreased T-cells with inverted CD4⁺/CD8⁺ T-cell ratio, while two GS patients were evaluated by endoscopy revealed mucosal edema and fine-granular or nodular appearance changes in the small intestine. Histological examination showed chronic inflammation and villous atrophy. A very interesting finding is that the inflammatory cell infiltration in the two GS cases was different. In one case, predominantly CD138⁺ plasma cells with only scattered CD3⁺ T-cells infiltration were revealed, while in another, it showed predominantly T-cells infiltration without plasma cells in the lamina propria. Although GS cases shared various clinical characteristics with common variable immunodeficiency (CVID) cases, they still differed from CVID cases in terms of its late onset, lack of familial clusters, low or absent peripheral blood B lymphocytes, absence of lymphoid hyperplasia, and plasma cells infiltration in the lamina propria in some patients. Although both patients had been diagnosed previously with recurrent diarrhea, respiratory infection, and thymoma, the association between these conditions and the possibility of GS was not recognized. The patients had remained misdiagnosed for 2 and 4 years, respectively, even after receiving the diagnosis of thymoma. The rarity of GS was likely the primary cause for the lack of disease recognition. Reporting of these cases will help to alert clinicians and raise awareness of this disease.

CONCLUSION: GS should be considered among the differential diagnoses for patients with unexplained recurrent diarrhea and opportunistic infection. Although it was regarded as a subset of CVID with thymoma, GS had a different clinical-pathological feature from CVID.

PMID:33851032 | PMC:PMC8019250 | DOI:10.1515/med-2021-0256

J Pediatr Hematol Oncol. 2021 Apr 9. doi: 10.1097/MPH.0000000000002101. Online ahead of print.

ABSTRACT

Although sideroblastic anemias (SAs) may be associated with different etiologies, deterioration of mitochondrial heme biosynthesis in bone marrow erythroid cells is a general abnormality. Congenital SA associated with immunodeficiency, periodic fever, and developmental delay is because of loss-of-function mutations in the TRNT1 gene. We report a patient with a novel homozygous mutation in the TRNT1 gene presenting with anemia with siderocytes, hypogammaglobulinemia, hepatosplenomegaly, and brittle hair but without periodic fever or developmental delay. The patient was presented to emphasize the power of reverse phenotyping in the differential diagnosis of primary immunodeficiency patients with atypical features and to raise awareness for TRNT1 disease in case of coexistent SA and hypogammaglobulinemia.

PMID:33843817 | DOI:10.1097/MPH.0000000000002101

Turk J Med Sci. 2021 Apr 12. doi: 10.3906/sag-2012-166. Online ahead of print.

ABSTRACT

BACKGROUND/AIM: Common variable immunodeficiency (CVID) is a heterogeneous primary deficiency characterized by hypogammaglobulinemia, recurrent infections, an increased risk of autoimmune disease, malignancy, and chronic inflammation. Proteinuria is one of the most important prognostic factors causing progression in kidney disease. Proteinuria causes tubulotoxicity, activates inflammatory markers that cause fibrosis, and consequently nephropathy progression. The data is scant in the literature regarding the inflammation and nephropathy in CVID. Hence, in the present study, we aimed to investigate the relationship between tubular dysfunction, proteinuria, and inflammation in patients with CVID.

MATERIALS AND METHODS: This was a cross-sectional study involving 27 patients with CVID (15 females, 12 males; mean age, 39.88 ± 13.47 years) and 18 control subjects (10 females, 8 males; mean age, 33.83 ± 7.97 years). Patients were evaluated for kidney functions including glomerular filtration rate, fractional excretion of sodium, metabolic acidosis, serum/urine anion gap 24-hour urine proteinuria and, were grouped in terms of proteinuria. Blood samples obtained from the patients with CVID were taken into 2 ml EDTA tube to evaluate peripheral NK cell subgroups according to CD56 and CD16 expression and CD3, CD4, CD 8 expression to determine subtypes T cells. These cells were evaluated by flow cytometry technique.

RESULTS: Urinary density, fractional excretion of sodium, proteinuria, and metabolic acidosis are found to be higher in patients with CVID when compared to healthy controls. In the bivariate correlation analysis, proteinuria was positively correlated with age (r=0.496, p=< 0.001), CD8+T cells percentage (r=0.427, p=0.02). Albumin, CRP, CD8+T cell percentage were found to be independent variables of proteinuria.

CONCLUSION: Increased chronic ongoing inflammation was found to be associated with proteinuria in patients with CVID. Hence, in routine outpatient clinics, proteinuria should not be overlooked in this group of patients.

PMID:33843169 | DOI:10.3906/sag-2012-166

Emerg Microbes Infect. 2021 Apr 8:1-23. doi: 10.1080/22221751.2021.1913973. Online ahead of print.

ABSTRACT

Monitoring the humoral protective immune response and its durability after SARS-CoV-2 infections is essential for risk assessment of reinfections, the improvement of diagnostic methods and the evaluation of vaccine trials. We have analyzed neutralizing antibodies and IgG responses specific to different antigens, including the inactivated whole-virion of SARS-CoV-2, the spike subunit 1 protein and its receptor binding domain, as well as the nucleocapsid protein. We show the dynamic developments of the responses from the early convalescent stages up to 9 months post symptoms onset in follow-up samples from 57 COVID-19 patients with varying clinical severity. By correlating antibody signals to neutralizing titers, valid diagnostic markers for the estimation of neutralizing protection could be identified.

PMID:33830901 | DOI:10.1080/22221751.2021.1913973

Clin Rev Allergy Immunol. 2021 Apr 5. doi: 10.1007/s12016-020-08828-z. Online ahead of print.

ABSTRACT

Common variable immunodeficiency disorders (CVIDs) are rare primary immunodeficiency diseases (PIDs) mostly associated with late onset antibody failure leading to immune system failure. Patients with CVID are predisposed to disabling complications such as bronchiectasis and systemic autoimmunity. In recent years a large number of genetic defects have become associated with these disorders. Patients with a causative mutation are deemed to have CVID-like disorders, while those with mutations predisposing to or modifying disease severity remain within the spectrum of CVID as defined by current diagnostic criteria. Next-generation sequencing (NGS) allows simultaneous analysis of multiple genes. Potential mutations identified from NGS are commonly evaluated with the American College of Medical Genetics (ACMG) variant interpretation criteria to determine their pathogenicity (causality). Patients with CVID and CVID-like disorders have marked genetic, allelic, and phenotypic heterogeneity. Although all patients with a CVID phenotype should undergo genetic testing, the complexity of the genetics associated with these disorders is challenging. Variants of unknown significance (VUS) remain a significant barrier to realising the full potential of NGS in CVID and CVID-like disorders. Here we explore the nuances of applying the ACMG criteria to patients with CVID and CVID-like disorders. Close collaboration between the clinician, bioinformatics, and genetics professionals will improve the diagnostic yield from genetic testing and reduce the frequency of VUS.

PMID:33818703 | DOI:10.1007/s12016-020-08828-z

Am J Clin Exp Immunol. 2021 Feb 15;10(1):37-43. eCollection 2021.

ABSTRACT

Introduction-Objective: X-linked agammaglobulinemia (XLA) is a primary immunodeficiency disease predominantly with antibody deficiency and characterized by recurrent pyogenic infections, absence of B cells and agammaglobulinemia. In this study, it is aimed to review the demographic data of our XLA patients and examine the frequency of severe bacterial and mild infections and benefits of immunoglobulin replacement therapies to reduce the rate of infections. In addition, correlations between genotypic results and clinical and laboratory findings were searched.

PATIENTS AND METHODS: In this study, 20 patients who were followed-up between 1995-2019 and diagnosed with XLA by flow cytometric and genetic tests were included. Demographic data, symptoms at admission and follow-up, laboratory data and radiologic imaging findings, previous infections, immunoglobulin replacement treatments, and genetic analysis results of the patients were recorded.

RESULTS: All patients in the study were male and the mean age of onset of symptoms was 60 months. The mean age at diagnosis was 72 months. A total of 19 different mutations were identified in the Bruton-tyrosine kinase gene, six of them were novel. Our eldest patient was 34 years old and the longest follow-up period was 24 years. Respiratory tract infections were the most common in the patients, only 35% of the causative agents were found in sputum cultures and H. influenzae type b (57.8%) was isolated most frequently. Both intravenous and subcutaneous immunoglobulin replacement therapies significantly reduced the number of severe bacterial infections and other mild infections.

CONCLUSION: XLA is a rare pediatric primary immunodeficiency disease and affected individuals require lifelong immunoglobulin replacement therapy. Immunoglobulin replacement prevents life-threatening infections and dramatically increases survival rates. The patients with regular treatment and follow-up, reach adulthood and has a high quality of life.

PMID:33815962 | PMC:PMC8012299

Front Immunol. 2021 Mar 18;12:655354. doi: 10.3389/fimmu.2021.655354. eCollection 2021.

ABSTRACT

Inborn errors of thymic stromal cell development and function lead to impaired T-cell development resulting in a susceptibility to opportunistic infections and autoimmunity. In their most severe form, congenital athymia, these disorders are life-threatening if left untreated. Athymia is rare and is typically associated with complete DiGeorge syndrome, which has multiple genetic and environmental etiologies. It is also found in rare cases of T-cell lymphopenia due to Nude SCID and Otofaciocervical Syndrome type 2, or in the context of genetically undefined defects. This group of disorders cannot be corrected by hematopoietic stem cell transplantation, but upon timely recognition as thymic defects, can successfully be treated by thymus transplantation using cultured postnatal thymic tissue with the generation of naïve T-cells showing a diverse repertoire. Mortality after this treatment usually occurs before immune reconstitution and is mainly associated with infections most often acquired pre-transplantation. In this review, we will discuss the current approaches to the diagnosis and management of thymic stromal cell defects, in particular those resulting in athymia. We will discuss the impact of the expanding implementation of newborn screening for T-cell lymphopenia, in combination with next generation sequencing, as well as the role of novel diagnostic tools distinguishing between hematopoietic and thymic stromal cell defects in facilitating the early consideration for thymus transplantation of an increasing number of patients and disorders. Immune reconstitution after the current treatment is usually incomplete with relatively common inflammatory and autoimmune complications, emphasizing the importance for improving strategies for thymus replacement therapy by optimizing the current use of postnatal thymus tissue and developing new approaches using engineered thymus tissue.

PMID:33815417 | PMC:PMC8012524 | DOI:10.3389/fimmu.2021.655354