MHC Class II Deficiency: Clinical, Immunological, and Genetic Insights in a Large Multicenter Cohort.

BACKGROUND: Major histocompatibility complex class II deficiency, a combined immunodeficiency, results from loss of HLA class II expression on antigen-presenting cells. Currently, hematopoietic stem cell transplantation stands as the sole curative approach, although factors influencing patient outcomes remain insufficiently explored. OBJECTIVES: To elucidate the clinical, immunologic, and genetic profiles associated with MHC-II deficiency and identify prognostic indicators that affect survival rates. METHODS: In this multicenter retrospective analysis, we gathered data from 35 patients with a diagnosis of MHC-II deficiency across 12 centers in Turkey. We recorded infection histories, gene mutations, immune cell subsets, and surface MHC-II expression on blood cells. We conducted survival analyses to evaluate the impact of various factors on patient outcomes. RESULTS: Predominant symptoms observed were pneumonia (n = 29; 82.9%), persistent diarrhea (n = 26; 74.3%), and severe infections (n = 26; 74.3%). The RFXANK gene mutation (n = 9) was the most frequent, followed by mutations in RFX5 (n = 8), CIITA (n = 4), and RFXAP (n = 2) genes. Patients with RFXANK mutations presented with later onset and diagnosis compared with those with RFX5 mutations (P =.0008 and .0006, respectively), alongside a more significant diagnostic delay (P = .020). A notable founder effect was observed in five patients with a specific RFX5 mutation (c.616G>C). The overall survival rate for patients was 28.6% (n = 10), showing a significantly higher proportion in individuals with hematopoietic stem cell transplantation (n = 8; 80%). Early death and higher CD8+ T-cell counts were observed in patients with the RFX5 mutations compared with RFXANK-mutant patients (P = .006 and .009, respectively). CONCLUSIONS: This study delineates the genetic and clinical panorama of MHC-II deficiency, emphasizing the prevalence of specific gene mutations such as RFXANK and RFX5. These insights facilitate early diagnosis and prognosis refinement, significantly contributing to the management of MHC-II deficiency.

Chronic granulomatous disease: A single-center experience in Central Anatolia.

BACKGROUND: Chronic granulomatous disease (CGD), one of the phagocytic cell defects, is the primary immunodeficiency caused by dysfunction of the NADPH oxidase complex in neutrophils. METHODS: The clinical, demographic and laboratory findings of 17 CGD patients who were followed-up between 2002 and 2021 were obtained retrospectively from the records of the patients. RESULTS: The number of male and female patients was 10/7. The median age at diagnosis was 5.3 months (range 4-120) for 3 patients with X-CGD, and 42.4 months (range 8-350) for 14 patients with AR-CGD. We have investigated rare CYBA exon 3-6 deletion in 7 patients and hotspot mutation with delGT at the beginning of exon 2 of NCF1 in 5 patients. The most common clinical findings were pneumonia and lymphadenitis with recurrent fever, respectively (41.2%, 35.3%). A total of 154 microbial infections requiring hospital admission (27 in 3 XL and 127 in 14 AR patients) were detected in the follow-up of the patients and median infection number for a patient was 9 in both groups. Eight of 17 patients had stem cell transplantation and the survival rate was 87.5%. CONCLUSIONS: X-CGD patients are more rapidly recognized by family history and severe infections than those with AR-CGD and early prophylaxis may decrease infectious episodes. We have investigated the large deletion suggesting a possible founder effect for CYBA exon 3-6 deletion in Central Anatolia. Additionally, HSCT transplantation leads to a high survival rate for the patients with CGD.

Long-term and real-world safety and efficacy of retroviral gene therapy for adenosine deaminase deficiency.

Adenosine deaminase (ADA) deficiency leads to severe combined immunodeficiency (SCID). Previous clinical trials showed that autologous CD34+ cell gene therapy (GT) following busulfan reduced-intensity conditioning is a promising therapeutic approach for ADA-SCID, but long-term data are warranted. Here we report an analysis on long-term safety and efficacy data of 43 patients with ADA-SCID who received retroviral ex vivo bone marrow-derived hematopoietic stem cell GT. Twenty-two individuals (median follow-up 15.4 years) were treated in the context of clinical development or named patient program. Nineteen patients were treated post-marketing authorization (median follow-up 3.2 years), and two additional patients received mobilized peripheral blood CD34+ cell GT. At data cutoff, all 43 patients were alive, with a median follow-up of 5.0 years (interquartile range 2.4-15.4) and 2 years intervention-free survival (no need for long-term enzyme replacement therapy or allogeneic hematopoietic stem cell transplantation) of 88% (95% confidence interval 78.7-98.4%). Most adverse events/reactions were related to disease background, busulfan conditioning or immune reconstitution; the safety profile of the real world experience was in line with premarketing cohort. One patient from the named patient program developed a T cell leukemia related to treatment 4.7 years after GT and is currently in remission. Long-term persistence of multilineage gene-corrected cells, metabolic detoxification, immune reconstitution and decreased infection rates were observed. Estimated mixed-effects models showed that higher dose of CD34+ cells infused and younger age at GT affected positively the plateau of CD3+ transduced cells, lymphocytes and CD4+ CD45RA+ naive T cells, whereas the cell dose positively influenced the final plateau of CD15+ transduced cells. These long-term data suggest that the risk-benefit of GT in ADA remains favorable and warrant for continuing long-term safety monitoring. Clinical trial registration: NCT00598481 , NCT03478670 .

Therapeutic modalities and clinical outcomes in a large cohort with LRBA deficiency and CTLA4 insufficiency.

BACKGROUND: LPS-responsive beige-like anchor (LRBA) deficiency (LRBA-/-) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA4) insufficiency (CTLA4+/-) are mechanistically overlapped diseases presenting with recurrent infections and autoimmunity. The effectiveness of different treatment regimens remains unknown. OBJECTIVE: Our aim was to determine the comparative efficacy and long-term outcome of therapy with immunosuppressants, CTLA4-immunoglobulin (abatacept), and hematopoietic stem cell transplantation (HSCT) in a single-country multicenter cohort of 98 patients with a 5-year median follow-up. METHODS: The 98 patients (63 LRBA-/- and 35 CTLA4+/-) were followed and evaluated at baseline and every 6 months for clinical manifestations and response to the respective therapies. RESULTS: The LRBA-/- patients exhibited a more severe disease course than did the CTLA4+/- patients, requiring more immunosuppressants, abatacept, and HSCT to control their symptoms. Among the 58 patients who received abatacept as either a primary or rescue therapy, sustained complete control was achieved in 46 (79.3%) without severe side effects. In contrast, most patients who received immunosuppressants as primary therapy (n = 61) showed either partial or no disease control (72.1%), necessitating additional immunosuppressants, abatacept, or transplantation. Patients with partial or no response to abatacept (n = 12) had longer disease activity before abatacept therapy, with higher organ involvement and poorer disease outcomes than those with a complete response. HSCT was performed in 14 LRBA-/- patients; 9 patients (64.2%) showed complete remission, and 3 (21.3%) continued to receive immunosuppressants after transplantation. HSCT and abatacept therapy gave rise to similar probabilities of survival. CONCLUSIONS: Abatacept is superior to immunosuppressants in controlling disease manifestations over the long term, especially when started early, and it may provide a safe and effective therapeutic alternative to transplantation.

Care of patients with inborn errors of immunity in thirty J Project countries between 2004 and 2021.

Introduction: The J Project (JP) physician education and clinical research collaboration program was started in 2004 and includes by now 32 countries mostly in Eastern and Central Europe (ECE). Until the end of 2021, 344 inborn errors of immunity (IEI)-focused meetings were organized by the JP to raise awareness and facilitate the diagnosis and treatment of patients with IEI. Results: In this study, meeting profiles and major diagnostic and treatment parameters were studied. JP center leaders reported patients' data from 30 countries representing a total population of 506 567 565. Two countries reported patients from JP centers (Konya, Turkey and Cairo University, Egypt). Diagnostic criteria were based on the 2020 update of classification by the IUIS Expert Committee on IEI. The number of JP meetings increased from 6 per year in 2004 and 2005 to 44 and 63 in 2020 and 2021, respectively. The cumulative number of meetings per country varied from 1 to 59 in various countries reflecting partly but not entirely the population of the respective countries. Altogether, 24,879 patients were reported giving an average prevalence of 4.9. Most of the patients had predominantly antibody deficiency (46,32%) followed by patients with combined immunodeficiencies (14.3%). The percentages of patients with bone marrow failure and phenocopies of IEI were less than 1 each. The number of patients was remarkably higher that those reported to the ESID Registry in 13 countries. Immunoglobulin (IgG) substitution was provided to 7,572 patients (5,693 intravenously) and 1,480 patients received hematopoietic stem cell therapy (HSCT). Searching for basic diagnostic parameters revealed the availability of immunochemistry and flow cytometry in 27 and 28 countries, respectively, and targeted gene sequencing and new generation sequencing was available in 21 and 18 countries. The number of IEI centers and experts in the field were 260 and 690, respectively. We found high correlation between the number of IEI centers and patients treated with intravenous IgG (IVIG) (correlation coefficient, cc, 0,916) and with those who were treated with HSCT (cc, 0,905). Similar correlation was found when the number of experts was compared with those treated with HSCT. However, the number of patients treated with subcutaneous Ig (SCIG) only slightly correlated with the number of experts (cc, 0,489) and no correlation was found between the number of centers and patients on SCIG (cc, 0,174). Conclusions: 1) this is the first study describing major diagnostic and treatment parameters of IEI care in countries of the JP; 2) the data suggest that the JP had tremendous impact on the development of IEI care in ECE; 3) our data help to define major future targets of JP activity in various countries; 4) we suggest that the number of IEI centers and IEI experts closely correlate to the most important treatment parameters; 5) we propose that specialist education among medical professionals plays pivotal role in increasing levels of diagnostics and adequate care of this vulnerable and still highly neglected patient population; 6) this study also provides the basis for further analysis of more specific aspects of IEI care including genetic diagnostics, disease specific prevalence, newborn screening and professional collaboration in JP countries.

Single-Center Study of 72 Patients with Severe Combined Immunodeficiency: Clinical and Laboratory Features and Outcomes.

Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various genetic causes, and if it remains untreated, patients succumb to infections during the first 2 years of life. PURPOSE AND METHODS: This study reported retrospective data from 72 infants diagnosed with SCID including their major clinical features, HSCT characteristics, and outcomes over a 20-year period (1997-2017). RESULTS: Sixty-one of 72 SCID patients in the study underwent HSCT from 1997 to 2017. Median ages at the time of diagnosis and transplantation were 3.5 months and 5 months, respectively. Consanguinity was present in 68% of the patients, and T - B - NK + phenotype was predominantly identified. The overall survival was 80.3% over a 20-year period. However, the patients transplanted during an active infection had a lower survival rate of 73.9% compared to 100% for patients transplanted infection-free or with a previous infection that had resolved. The survival rate was significantly higher among recipients of HLA-identical transplants (92.9%), compared to recipients of mismatched related transplants (70%). The overall survival increased from 50 (1997-2006) to 85% (2007-2017) during the last 10 years. CONCLUSIONS: This is one of the largest single-center studies in Turkey with extensive experience about SCID patients. Early diagnosis of SCID patients before the onset of an infection and early transplantation are shown to be extremely important factors affecting the outcome and increasing the survival regardless of the donor type based on the results of this study.

Allogeneic hematopoietic stem cell and liver transplantation in a young girl with dedicator of cytokinesis 8 protein deficiency.

DOCK8 deficiency is a rare inherited combined immunodeficiency, caused by mutations in the DOCK8 gene. We describe a case with DOCK8 deficiency associated with severe CLD in whom orthotopic LT was performed successfully after allogeneic HSCT. A 5 year-old girl with DOCK8 deficiency presented with mild direct hyperbilirubinemia and abnormal GGT level and without a previous history of jaundice. She had severe growth retardation, hepatosplenomegaly and generalized eczema. Progressive worsening of CLD was observed within 4 months. Investigations for etiology of liver disease were negative. Liver biopsy showed bridging necrosis, cholestasis and, cirrhosis. Recurrent immune hemolytic crisis and several viral infections developed in follow-up. She underwent whole cadaveric LT for end-stage liver disease (ESLD) 1 year after allogenic HSCT from a full matched related donor. The postoperative course was uneventful. The patient is alive with normal liver function and moderate skin graft versus host disease for 36 months after LT. In conclusion DOCK8 deficiency can be associated with severe CLD. Successful LT following HSCT is possible in patients with ESLD in DOCK8 deficiency. The timing of LT is challenging in patients requiring both HSCT and LT since conditioning regimens for HSCT can be highly hepatotoxic and the patients with suboptimal liver function can become decompensated during HSCT.

Abatacept as a Long-Term Targeted Therapy for LRBA Deficiency.

BACKGROUND: LPS-responsive beige-like anchor (LRBA) deficiency presents with susceptibility to infections, autoimmunity, and lymphoproliferation. The long-term efficacy of cytotoxic T-lymphocyte-associated antigen 4-immunoglobulin (abatacept) as targeted therapy for its immune dysregulatory features remains to be established. OBJECTIVE: To determine the clinical and immunologic features of LRBA deficiency and long-term efficacy of abatacept treatment in controlling the different disease manifestations. METHODS: Twenty-two LRBA-deficient patients were recruited from different immunology centers and followed prospectively. Eighteen patients on abatacept were evaluated every 3 months for long-term clinical and immunologic responses. LRBA expression, lymphocyte subpopulations, and circulating T follicular helper cells were determined by flow cytometry. RESULTS: The mean age of the patients was 13.4 ± 7.9 years, and the follow-up period was 3.4 ± 2.3 years. Recurrent infections (n = 19 [86.4%]), immune dysregulation (n = 18 [81.8%]), and lymphoproliferation (n = 16 [72.7%]) were common clinical features. The long-term benefits of abatacept in 16 patients were demonstrated by complete control of lymphoproliferation and chronic diarrhea followed by immune dysregulation, most notably autoimmune cytopenias. Weekly or every other week administration of abatacept gave better disease control compared with every 4 weeks. There were no serious side effects related to the abatacept therapy. Circulating T follicular helper cell frequencies were found to be a reliable biomarker of disease activity, which decreased on abatacept therapy in most subjects. However, high circulating T follicular helper cell frequencies persisted in 2 patients who had a more severe disease phenotype that was relatively resistant to abatacept therapy. CONCLUSIONS: Long-term abatacept therapy is effective in most patients with LRBA deficiency.

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiency Patients in the Black Sea Region of Turkey.

Hematopoietic stem cell transplantation is a promising curative therapy for many combined primary immunodeficiencies and phagocytic disorders. We retrospectively reviewed pediatric cases of patients diagnosed with primary immunodeficiencies and scheduled for hematopoietic stem cell transplantation. We identified 22 patients (median age, 6 months; age range, 1 month to 10 years) with various diagnoses who received hematopoietic stem cell transplantation. The patient diagnoses included severe combined immunodeficiency (n=11), Chediak-Higashi syndrome (n=2), leukocyte adhesion deficiency (n=2), MHC class 2 deficiency (n=2), chronic granulomatous syndrome (n=2), hemophagocytic lymphohistiocytosis (n=1), Wiskott-Aldrich syndrome (n=1), and Omenn syndrome (n=1). Of the 22 patients, 7 received human leukocyte antigen-matched related hematopoietic stem cell transplantation, 12 received haploidentical hematopoietic stem cell transplantation, and 2 received matched unrelated hematopoietic stem cell transplantation. The results showed that 5 patients had graft failure. Fourteen patients survived, yielding an overall survival rate of 67%. Screening newborn infants for primary immunodeficiency diseases may result in timely administration of hematopoietic stem cell transplantation.

Students' unchanging smoking habits in urban and rural areas in the last 15 years.

BACKGROUND: Smoking is the main preventable public health problem particularly for youth worldwide. The aim of the present study was to determine the prevalence of smoking habits among students at secondary and high schools, and to compare the findings with those of a study conducted 15 years ago in the same area. METHODS: In this cross-sectional study 6212 students (51.2% female; 48.8% male) were selected randomly from rural and urban areas in Samsun. All students completed a face-to-face questionnaire. RESULTS: The overall prevalence of smoking was 13.0% (male students, 18.1%; female students, 8.2%). The mean starting age of smoking was 14.1 ± 1.5 years. Prevalence of smoking was 15.7% in urban areas and 8.1% in rural areas. The most important factors for starting smoking were social group and families. Compared with a study conducted 15 years previously in the same area for male students, smoking prevalence was increased in rural, but decreased in urban areas. CONCLUSIONS: Smoking prevalence in students in Samsun was similar to that in a study conducted 15 years previously. It is important to use anti-smoking campaigns directly targeted at teenager and they should be fully informed of the harmful effects of smoking.

Sodium nitroprusside and toxic epidermal necrolysis.

Sodium nitroprusside (SNP) is one of the most widely used parenteral antihypertensive agents in severe hypertension management. Toxic epidermal necrolysis (TEN) is a rare, mostly drug-induced, severe muco-cutoneous reaction with various complications and high mortality. A fifteen years old girl who is on hemodialysis for chronic renal insufficiency and was hospitalized for emergency management of hypertension, developed a diffuse maculopapular rash within minutes after SNP infusion. In 72 hours, approximately 40% of the body surface was involved with skin detachment indicating epidermal necrolysis and a skin biopsy confirmed the diagnosis of TEN. To the best of our knowledge there is no report of an association of SNP and TEN in the English literature and the clinical data exemplifying consequent IgE and non-IgE mediated hypersensitivity reactions are scanty. With this report we wanted to present a rare complication of SNP infusion indicating another rare occurrence of sequential IgE and non-IgE mediated hypersensitivity reactions.

Foreign body aspiration in childhood: evaluation of diagnostic parameters.

BACKGROUND: Foreign body aspiration (FBA) is one of the most important preventable causes of childhood mortality and morbidity. OBJECTIVE: The aim of this study was to define the clinical and radiological features of FBA and investigate the diagnostic value of various parameters used to diagnose FBA. METHODS: The medical records of 147 children who were admitted to the hospital with a diagnosis of suspected FBA were examined. The sensitivity and specificity of the parameters used for the diagnosis of FBA and their predictive values were calculated. RESULTS: Of the patients, 75.5% were younger than 3 years, and 61.2% were male. Peak incidence was found in 18 months. A negative bronchoscopy rate of 19.7% was found, and 92.6% of these patients were younger than 3 years. The parameter with the highest diagnostic value was the presence of aspiration history (the sensitivity and positive and negative predictive values were 97%, 89%, and 80%, respectively). No significant difference was found in the classic triad of FBA (sudden onset of cough, wheezing, and unilaterally decreased breath sounds) between patients with and without FBA. The specificity and positive predictive value of the classic triad were high, and the sensitivity and negative predictive value were low (85% and 78%, and 13% and 19%, respectively). CONCLUSIONS: Especially, male children younger than 3 years have an increased risk of FBA. Neither clinical symptoms nor the radiological findings alone are sufficiently specific and sensitive in diagnosing FBA. The most important factor for diagnosis is the presence of aspiration history.