Genetic Evaluation of the Patients with Clinically Diagnosed Inborn Errors of Immunity by Whole Exome Sequencing: Results from a Specialized Research Center for Immunodeficiency in Türkiye.

Molecular diagnosis of inborn errors of immunity (IEI) plays a critical role in determining patients' long-term prognosis, treatment options, and genetic counseling. Over the past decade, the broader utilization of next-generation sequencing (NGS) techniques in both research and clinical settings has facilitated the evaluation of a significant proportion of patients for gene variants associated with IEI. In addition to its role in diagnosing known gene defects, the application of high-throughput techniques such as targeted, exome, and genome sequencing has led to the identification of novel disease-causing genes. However, the results obtained from these different methods can vary depending on disease phenotypes or patient characteristics. In this study, we conducted whole-exome sequencing (WES) in a sizable cohort of IEI patients, consisting of 303 individuals from 21 different clinical immunology centers in Türkiye. Our analysis resulted in likely genetic diagnoses for 41.1% of the patients (122 out of 297), revealing 52 novel variants and uncovering potential new IEI genes in six patients. The significance of understanding outcomes across various IEI cohorts cannot be overstated, and we believe that our findings will make a valuable contribution to the existing literature and foster collaborative research between clinicians and basic science researchers.

A rare disease with many faces: A multicenter registry of IgG4-related disease in children.

OBJECTIVES: We aimed to report the characteristics of pediatric IgG4-related disease (IgG4-RD) through a multicentre registry, to assess disease clusters, and to evaluate the performances of the 2019 American College of Rheumatology and European League Against Rheumatism (ACR/EULAR) classification criteria and the 2020 revised comprehensive diagnostic (RCD) criteria in this cohort. METHODS: Data of IgG4-RD patients in 13 pediatric rheumatology centers were recorded to a web-based registration system. The diagnosis of IgG4-RD was made according to the 2011 comprehensive diagnostic criteria. RESULTS: Thirty-five children (19 females and 16 males) with IgG4-RD were enrolled. The median age at diagnosis was 13.3 (25p-75p; 9.9-15.2) years. The most common organ involvement was the eye (n = 21, 60%), followed by lymph nodes (n = 12, 34.3%), musculoskeletal system (n = 12, 34.3%), and neurological system (n = 9, 25.7%). We identified three clusters in our study cohort: those with eye involvement (n = 11, 31.4%), those with eye involvement and neurological findings (n = 15, 42.9%), and those with pancreato-hepatobiliary disease and lymph node involvement (n = 9, 25.7%). Serum IgG4 levels were high in 19 out of 28 patients (67.8%). All patients except one received corticosteroid treatment, and azathioprine was the most preferred drug as a steroid-sparing agent. The sensitivities of the 2019 ACR/EULAR classification criteria and the 2020 RCD criteria were 5.7% and 88.5%, respectively. CONCLUSION: IgG4-RD has a wide variety of clinical manifestations, however in children the most common presentation was orbital involvement. The 2020 RCD criteria had a better performance whereas the 2019 ACR/EULAR classification criteria performed poorly in pediatric patients.

Activation-Induced Cytidine Deaminase Expression in Human B Cell Precursors Is Essential for Central B Cell Tolerance.

Activation-induced cytidine deaminase (AID), the enzyme-mediating class-switch recombination (CSR) and somatic hypermutation (SHM) of immunoglobulin genes, is essential for the removal of developing autoreactive B cells. How AID mediates central B cell tolerance remains unknown. We report that AID enzymes were produced in a discrete population of immature B cells that expressed recombination-activating gene 2 (RAG2), suggesting that they undergo secondary recombination to edit autoreactive antibodies. However, most AID+ immature B cells lacked anti-apoptotic MCL-1 and were deleted by apoptosis. AID inhibition using lentiviral-encoded short hairpin (sh)RNA in B cells developing in humanized mice resulted in a failure to remove autoreactive clones. Hence, B cell intrinsic AID expression mediates central B cell tolerance potentially through its RAG-coupled genotoxic activity in self-reactive immature B cells.

Rhupus syndrome in children: A multi-center retrospective cohort study and literature review.

OBJECTIVE: In this study, we aimed to evaluate the characteristics of pediatric rhupus patients including all the related series in the literature. METHODS: Thirty pediatric patients with rhupus syndrome from 12 different centers in Turkey were included in this study. The literature was also reviewed for pediatric patients with rhupus syndrome. RESULTS: The most prominent phenotype of these 30 patients was juvenile idiopathic arthritis (JIA) (60%) at the disease onset and SLE (73.3%) at the last visit. Major SLE-related organ involvements were skin (80%), hematological system (53.3%), and kidney (23.3%). Arthritis was polyarticular (73.3%), asymmetric (66.7%), and erosive (53.3%) in most patients. Hydroxychloroquine (100%), glucocorticoids (86.7%), and mycophenolate mofetil (46.7%) were mostly used for SLE, while glucocorticoids (76.6%), methotrexate (73.3%), and nonsteroidal anti-inflammatory drugs (NSAIDs) (57.6%) were mainly preferred for JIA. Our literature search revealed 20 pediatric patients with rhupus syndrome (75% were RF positive). The most prominent phenotype was JIA (91.7%) at the disease onset and SLE (63.6%) at the last visit. Major SLE-related organ involvements were skin (66.7%), hematological system (58.3%), and kidney (58.3%). Arthritis was polyarticular (77.8%), asymmetric (63.6%), and erosive (83.3%) in most patients. Glucocorticoid (100%), hydroxychloroquine (76.9%), and azathioprine (46.2%) were mostly used for SLE, while methotrexate (76.9%) and NSAIDs (46.2%) were mainly preferred for the JIA phenotype. CONCLUSION: Our study is the largest cohort in the literature evaluating pediatric rhupus cases. Most of the pediatric patients had polyarticular, asymmetric, and erosive arthritis, as well as organ involvements associated with SLE, including the skin, hematological system, and kidney.

Exploring gastrointestinal manifestations in childhood onset systemic lupus erythematosus - Insights from a multicenter study.

OBJECTIVE: Systemic lupus erythematosus (SLE) constitutes an autoimmune disorder with potential involvement of the gastrointestinal system (GIS). Our objective was to assess the gastrointestinal (GI) manifestations in patients diagnosed with childhood onset SLE. METHODS: The study cohort consisted of 123 patients with childhood onset-SLE and GIS involvement from 16 referral departments of pediatric rheumatology. All participants met the Systemic Lupus International Collaborating Clinics criteria. RESULTS: Out of 123 patients, 78 (63.4%) exhibited GIS involvement at the initial SLE diagnosis, whereas the remaining 45 (36.6%) developed GI symptoms after a median duration of 12 (3-140) months. Eighty-two (66.7%) individuals experienced symptoms related to the GI tract, whereas the remaining patients received a diagnosis of GI involvement through laboratory assessments. The predominant initial GIS involvement symptom was abdominal pain, observed in 77 (62.6%) patients, followed by elevated hepatic transaminases in 70 (56.9%), hepatomegaly in 40 (32.5%), diarrhea in 26 (21.1%), and jaundice in 11 (8.9%) patients. The GIS involvement was associated with SLE in 82 (78.6%), while it resulted from drug-related adverse events in 35 (28.5%) patients or comorbidities in 6 (0.5%) patients. CONCLUSION: GIS involvement should be considered in all childhood onset-SLE patients, especially in the presence of suggestive symptoms or elevated hepatic transaminases. It is also crucial to consider SLE in the differential diagnosis of GIS manifestations in children. Apart from GIS involvement directly associated with SLE, adverse events of drugs should be kept in mind.

Cases with the H syndrome presenting with skin and bone findings.

BACKGROUND: The H syndrome is an autosomal recessive disease characterized by hyperpigmentation, hypertrichosis and sensorineural hearing loss. METHODS: A mutation in the coding of the human equilibrative nucleoside transporter 3 (hENT3) within the SLC29A3 gene on chromosome 10q22 leads to the manifestation of this disease. In this report, we present two cases of H syndrome. RESULTS: The first patient exhibits hyperpigmentation, hypogonadism, Type 1 diabetes mellitus, arthritis and osteoporosis. The second patient experiences hyperpigmentation, hypertrichosis, osteopenia and hypogonadism. CONCLUSION: Our objective is to broaden the clinical spectrum of H syndrome, highlighting the involvement of arthritis, hyperinflammation and low bone mineral density in individuals with this disorder.

Neurological involvement in patients with primary immunodeficiency.

INTRODUCTION: Primary immunodeficiency diseases (PID) are defined by recurrent infections, allergies, autoimmunity, and malignancies. Neurologic symptoms are one of the major components of some immunodeficiency syndromes, such as Ataxia-Telangiectasia (AT), Nijmegen breakage syndrome (NBS), and Purine Nucleoside Phosphorylase (PNP) deficiency, which are considered as the primary involvement. Various pathological mechanisms, DNA repair disorders, metabolic abnormalities, and autoimmune phenomena have also been linked with neurological conditions. MATERIALS AND METHOD: We retrospectively assessed the neurological involvement in 108 patients out of 6000 with PID in this study. RESULTS: The female/male ratio of the cases was 49/59, and the median age was 13 years (min = 1; max = 60). Neurological problems were detected at a median age of 7 years (min = 0.5; max = 30). Di George Syndrome (DGS) and CVID (common variable immunodeficiency) were the most common diseases in our cohort (n = 31, 30% and n = 30, 27%, respectively). The most frequent outcomes were cognitive delay (n = 63, 58%), epilepsy (n = 25, 23%), and ataxia (n = 20, 18%). Central nervous system involvement was found in 99% of the patients (n = 107), and peripheral nervous system complication was found in only one patient with CVID and chronic inflammatory demyelinating polyneuropathy (CDIP). Cranial MRI was found to be abnormal in 74% (n = 80) of the patients. MRI findings included cerebellar atrophy (n = 33, 34%), white matter lesion (n = 27, 28.4%), cerebral atrophy (n = 21, 22.3%), gray matter lesion (n = 6, 6.3%), hydrocephalus (n = 5, 5,3%), and pituitary gland lesion (n = 3, 3.2%), intracranial hemorrhage (n = 3, 3%), intracranial vasculitis (n = 3, 2.7%), and arterio-venous malformation (n = 1, 0,9%). Primary involvement (a component of the disease) was 60% (n = 65), and secondary (infection or autoimmunity) and tertiary involvements (structural or incidental lesions) contributed 20% (n = 20) each in the patients. CONCLUSION: In this study, we describe the various neurologic findings of patients with PID. The neurologic presentation may represent the initial manifestation of certain types of PID. Early diagnosis and treatment are essential to prevent or reduce further neurologic damages.

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.

Interferons dominate damage and activity in juvenile scleroderma.

OBJECTIVES: Juvenile scleroderma is a heterogeneous group of diseases associated with sclerotic skin lesions, grouped as juvenile systemic sclerosis and juvenile localized scleroderma. This study aims to measure the cytokine and chemokine levels involved in interferon (IFN) signalling in patients with juvenile scleroderma and determine their correlation with disease severity. METHODS: Twenty-nine juvenile localized scleroderma, five juvenile systemic sclerosis, and nine healthy controls were included in the study. Cytokines and chemokines involved in IFN gene signalling (IL-1, IL-6, IL-8, IP-10, MCP1, TNF-α, CXCL-11, IFN-α, IFN-ß, IFN-γ) and IFN-stimulated genes (ISGs), including IFI27, IFI44, ISIG15, IFIT1, OAS1, RSAD2, were measured by ELISA and RT-PCR method, respectively. RESULTS: A significant increase in IFN-α, IFN-ß, IFN-γ, TNF-α, IL-1, IL-6 IL-8, IP-10, and MCP1 levels was observed in patients with juvenile systemic sclerosis compared with the healthy control group. Furthermore, IFN-α and IP-10 were elevated in both juvenile localized scleroderma and juvenile systemic sclerosis compared to the healthy control group. IFN-γ and IFN-α positively correlated with LoSAI and LoSDI levels, respectively. According to PGA-A analysis, IFN-ß, IFN-γ, TNF-α, IL-8, IP10, MCP1, and CXCL11 were significantly higher in active disease than in the inactive state in both groups. CONCLUSION: The results suggest that IFN signalling may be impaired in patients with juvenile scleroderma. Significant changes were observed in cytokines and genes related to IFN signalling, which may have a crucial role in monitoring disease activity. In addition, we have gained important insights into the possibility of using IFN-α and IFN-γ as biomarkers for monitoring juvenile scleroderma activity and damage.

Defective Treg generation and increased type 3 immune response in leukocyte adhesion deficiency 1.

In 15 Turkish LAD-1 patients and controls, we assessed the impact of pathogenic ITGB2 mutations on Th17/Treg differentiation and functions, and innate lymphoid cell (ILC) subsets. The percentage of peripheral blood Treg cells, in vitro-generated induced Tregs differentiated from naive CD4+ T cells were decreased despite the elevated absolute counts of CD4+ cells in LAD-1 patients. Serum IL-23 levels were elevated in LAD-1 patients. Post-curdlan stimulation, LAD-1 patient-derived PBMCs produced more IL-17A. Additionally, the percentages of CD18-deficient Th17 cells expanded from total or naïve CD4+ T cells were higher. The blood ILC3 subset was significantly elevated in LAD-1. Finally, LAD-1 PBMCs showed defects in trans-well migration and proliferation and were more resistant to apoptosis. Defects in de novo generation of Tregs from CD18-deficient naïve T cells and elevated Th17s, and ILC3s in LAD-1 patients' peripheral blood suggest a type 3-skewed immunity and may contribute to LAD-1-associated autoimmune symptoms.

Clinical and Osteopetrosis-Like Radiological Findings in Patients with Leukocyte Adhesion Deficiency Type III.

BACKGROUND: Leukocyte and platelet integrin function defects are present in leukocyte adhesion deficiency type III (LAD-III) due to mutations in FERMT3. Additionally, osteoclast/osteoblast dysfunction develops in LAD-III. AIM: To discuss the distinguishing clinical, radiological, and laboratory features of LAD-III. METHODS: This study included the clinical, radiological, and laboratory characteristics of twelve LAD-III patients. RESULTS: The male/female ratio was 8/4. The parental consanguinity ratio was 100%. Half of the patients had a family history of patients with similar findings. The median age at presentation and diagnosis was 18 (1-60) days and 6 (1-20) months, respectively. The median leukocyte count on admission was 43,150 (30,900-75,700)/µL. The absolute eosinophil count was tested in 8/12 patients, and eosinophilia was found in 6/8 (75%). All patients had a history of sepsis. Other severe infections were pneumonia (66.6%), omphalitis (25%), osteomyelitis (16.6%), gingivitis/periodontitis (16%), chorioretinitis (8.3%), otitis media (8.3%), diarrhea (8.3%), and palpebral conjunctiva infection (8.3%). Four patients (33.3%) received hematopoietic stem cell transplantation (HSCT) from HLA-matched-related donors, and one deceased after HSCT. At initial presentation, 4 (33.3%) patients were diagnosed with other hematologic disorders, three patients (P5, P7, and P8) with juvenile myelomonocytic leukemia (JMML), and one (P2) with myelodysplastic syndrome (MDS). CONCLUSION: In LAD-III, leukocytosis, eosinophilia, and bone marrow findings may mimic pathologies such as JMML and MDS. In addition to non-purulent infection susceptibility, patients with LAD-III exhibit Glanzmann-type bleeding disorder. In LAD-III, absent integrin activation due to kindlin-3 deficiency disrupts osteoclast actin cytoskeleton organization. This results in defective bone resorption and osteopetrosis-like radiological changes. These are distinctive features compared to other LAD types.

Atypical Localization of Eczema Discriminates DOCK8 or STAT3 Deficiencies from Atopic Dermatitis.

PURPOSE: Autosomal recessive dedicator of cytokinesis 8 (DOCK8-/-) and autosomal dominant signal transducer and activator of transcription 3 (STAT3-/+) deficiencies are inborn errors of immunity (IEI) disorders present with the classic features of eczema and create a dilemma during differentiation from atopic dermatitis (AD). Therefore, an appropriate approach is required for eczema to diagnose DOCK8-/- and STAT3-/+ early. Here, we described a set of clinical and immunological variables, including atypical AD localizations and lymphocyte subsets, to differentiate DOCK8-/- or STAT3-/+ from AD. METHODS: This multicenter study involved 100 patients with DOCK8-/- and STAT3-/+ and moderate/severe AD. We recruited disease manifestations, including detailed localizations of eczema, infections, and allergy. Principle component analysis (PCA) was used to discriminate DOCK8-/- or STAT3-/+ from AD. RESULTS: There were 43 patients with DOCK8-/-, 23 with STAT3-/+, and 34 with AD. Pneumonia, severe infections, mucocutaneous candidiasis, and skin abscesses were commonly observed in DOCK8 and STAT3 deficiencies. Atypical skin involvement with neonatal rash, retro auricular, axillary, sacral, and genital eczema discriminate DOCK8-/- and STAT3-/+ from AD with high specificity ranges between 73.5 and 94.1% and positive predictive index ranges between 55 and 93.1%. Together with using absolute numbers of CD3+, CD4+, and CD8+ T cells, the combined clinical and laboratory features showed perfect differentiation between DOCK8-/- or STAT3-/+ and AD via PCA. CONCLUSIONS: The described features can be easily implemented by physicians providing early diagnosis of DOCK8 and STAT3 deficiencies.

Consensus Middle East and North Africa Registry on Inborn Errors of Immunity.

BACKGROUND: Inborn errors of immunity (IEIs) are a heterogeneous group of genetic defects of immunity, which cause high rates of morbidity and mortality mainly among children due to infectious and non-infectious complications. The IEI burden has been critically underestimated in countries from middle- and low-income regions and the majority of patients with IEI in these regions lack a molecular diagnosis. METHODS: We analyzed the clinical, immunologic, and genetic data of IEI patients from 22 countries in the Middle East and North Africa (MENA) region. The data was collected from national registries and diverse databases such as the Asian Pacific Society for Immunodeficiencies (APSID) registry, African Society for Immunodeficiencies (ASID) registry, Jeffrey Modell Foundation (JMF) registry, J Project centers, and International Consortium on Immune Deficiency (ICID) centers. RESULTS: We identified 17,120 patients with IEI, among which females represented 39.4%. Parental consanguinity was present in 60.5% of cases and 27.3% of the patients were from families with a confirmed previous family history of IEI. The median age of patients at the onset of disease was 36 months and the median delay in diagnosis was 41 months. The rate of registered IEI patients ranges between 0.02 and 7.58 per 100,000 population, and the lowest rates were in countries with the highest rates of disability-adjusted life years (DALY) and death rates for children. Predominantly antibody deficiencies were the most frequent IEI entities diagnosed in 41.2% of the cohort. Among 5871 patients genetically evaluated, the diagnostic yield was 83% with the majority (65.2%) having autosomal recessive defects. The mortality rate was the highest in patients with non-syndromic combined immunodeficiency (51.7%, median age: 3.5 years) and particularly in patients with mutations in specific genes associated with this phenotype (RFXANK, RAG1, and IL2RG). CONCLUSIONS: This comprehensive registry highlights the importance of a detailed investigation of IEI patients in the MENA region. The high yield of genetic diagnosis of IEI in this region has important implications for prevention, prognosis, treatment, and resource allocation.

Clinical and laboratory findings in patients with leukocyte adhesion deficiency type I: A multicenter study in Turkey.

Leukocyte adhesion deficiency type I is a rare primary immunodeficiency disorder characterized by mutations in the ITGB2 gene encoding CD18. We present clinical and immunological features of 15 patients with leukocyte adhesion deficiency type 1 (LAD-1). Targeted next-generation sequencing was performed with either a primary immunodeficiency gene panel comprising 266 genes or a small LAD-panel consisting of five genes for genetic analysis. To measure the expression level of integrins on the leukocyte surface, flow cytometry analysis was performed. The median age of the patients at diagnosis was 3 (1-48) months. Eleven (73%) of the 15 patients had a LAD-1 diagnosis in their first 6 months and 14 (93%) patients had consanguineous parents. Delayed separation of the umbilical cord was present in 80% (n = 12) of the patients in our cohort, whereas omphalitis was observed in 53% (n = 8) of the patients. Leukocytosis with neutrophil predominance was observed in 73% (n = 11) patients. Nine distinct variants in the ITGB2 gene in 13 of the 15 patients with LAD-1 were characterized, two of which (c.305_306delAA and c.779_786dup) are novel homozygous mutations of ITGB2. Four unrelated patients from Syria had a novel c.305_306delAA mutation that might be a founder effect for patients of Syrian origin. Four (27%) patients underwent hematopoietic stem cell transplantation. Two patients died because of HSCT complications and the other two are alive and well. Early differential diagnosis of the patients is critical in the management of the disease and genetic evaluation provides a basis for family studies and genetic counseling.

Infliximab therapy in an infant with Netherton syndrome.

We present a patient with Netherton syndrome and severe skin manifestations treated with infliximab. By 6 months of age, the child had intractable pruritus, scaling, dry skin, and generalized eczematous lesions resistant to conventional therapies for atopic dermatitis. Clinical improvement was observed following the third infusion of infliximab, and by 12 months of age, the skin lesions completely resolved. Infliximab is a promising option for the management of skin inflammation in Netherton syndrome, even in infants.

Long-term outcome of LRBA deficiency in 76 patients after various treatment modalities as evaluated by the immune deficiency and dysregulation activity (IDDA) score.

BACKGROUND: Recent findings strongly support hematopoietic stem cell transplantation (HSCT) in patients with severe presentation of LPS-responsive beige-like anchor protein (LRBA) deficiency, but long-term follow-up and survival data beyond previous patient reports or meta-reviews are scarce for those patients who do not receive a transplant. OBJECTIVE: This international retrospective study was conducted to elucidate the longitudinal clinical course of patients with LRBA deficiency who do and do not receive a transplant. METHOD: We assessed disease burden and treatment responses with a specially developed immune deficiency and dysregulation activity score, reflecting the sum and severity of organ involvement and infections, days of hospitalization, supportive care requirements, and performance indices. RESULTS: Of 76 patients with LRBA deficiency from 29 centers (median follow-up, 10 years; range, 1-52), 24 underwent HSCT from 2005 to 2019. The overall survival rate after HSCT (median follow-up, 20 months) was 70.8% (17 of 24 patients); all deaths were due to nonspecific, early, transplant-related mortality. Currently, 82.7% of patients who did not receive a transplant (43 of 52; age range, 3-69 years) are alive. Of 17 HSCT survivors, 7 are in complete remission and 5 are in good partial remission without treatment (together, 12 of 17 [70.6%]). In contrast, only 5 of 43 patients who did not receive a transplant (11.6%) are without immunosuppression. Immune deficiency and dysregulation activity scores were significantly lower in patients who survived HSCT than in those receiving conventional treatment (P = .005) or in patients who received abatacept or sirolimus as compared with other therapies, and in patients with residual LRBA expression. Higher disease burden, longer duration before HSCT, and lung involvement were associated with poor outcome. CONCLUSION: The lifelong disease activity, implying a need for immunosuppression and risk of malignancy, must be weighed against the risks of HSCT.

The evaluation of malignancies in Turkish primary immunodeficiency patients; a multicenter study.

BACKGROUND: There are no data regarding the prevalence of malignancies in patients with primary immunodeficiency (PID) in Turkey. Along with the prevalence of malignancy, we aimed to present the types of malignancy and define the underlying immune deficiency of the patients. METHOD: Between the years 1992 and 2018, from five tertiary immunology clinics, fifty-nine patients with PID who developed malignancy were included. All patients were evaluated for demographics, clinical features, and prognosis. RESULTS: The prevalence of malignancy in our cohort was detected as 0.9% (59/6392). The male-to-female ratio was 1.8 (38/21), and the median age of patients was 14 years (range: 1.5-51). The median age at diagnosis of malignancy was 10 years (range: 1.5-51). Ataxia-telangiectasia was the most frequent PID in patients with malignancy (n = 19, 32.2%), and non-Hodgkin lymphoma was the most common malignancy (n = 32, 51.6%). The rate of malignancy in DOCK8 deficiency (n = 7/43, 16.3%) was higher than AT (n = 19/193, 9.8%), Wiskott-Aldrich syndrome (n = 2/22, 9.1%), and common variable immunodeficiency (n = 11/205, 5.4%). EBV quantitative PCR was positive in 16 out of 53 patients (30.2%). Three patients had secondary malignancies. Remission was achieved in 26 patients (44.1%). However, 31 patients (52.5%) died. Two patients (3.4%) are still on chemotherapy. CONCLUSION: This study is the largest cohort investigating the association of malignancy in patients with PID in Turkey. While lymphoid malignancies were the most common malignancy and observed more frequently in AT patients, the risk for malignancy was higher in patients with DOCK8 deficiency compared to AT.

Central nervous system variations and abnormalities in anhidrotic ectodermal dysplasia (AED): neuroimaging findings.

BACKGROUND: Anhidrotic ectodermal dysplasia (AED) is a rare, mostly X-linked recessive genodermatosis, characterized by congenital defects of ectodermal derivative structures as the central nervous system (CNS) is primarily ectodermal in origin. PURPOSE: To evaluate CNS variations and abnormalities in AED. MATERIAL AND METHODS: A retrospective analysis was made of the neurological and neuroimaging findings of 17 children (12 boys, 5 girls; median age = 8 years; age range = 2-14 years) diagnosed with AED in our pediatric clinics during 2008-2016. The pattern of CNS variation and abnormalities were evaluated by comparing of these findings with an age- and gender-matched healthy control group with no family history. RESULTS: Of the 17 AED cases identified on the basis of neuroimaging findings, 6 (35.3%) were seen to be normal. Associated CNS variation and abnormalities including cavum septum pellucidum (35.3%), callosal dysgenesis (11.8%), prominent Virchow-Robin spaces (64.7%), cortical sulcal dilation (41.1%), mega cisterna magna (35.3%), focal cortical dysplasia (11.8%), and delayed myelination (58.8%) were observed in 11 (64.7%) children with AED. CONCLUSION: AED suggests a spectrum of CNS variation and abnormalities, presenting with neurological and neuroimaging findings, demonstrated in the embryonic surface- and neuro-ectoderm derived structures. The results of this study suggest that CNS variation and abnormalities might be associated with AED.

Hematopoietic stem cell transplantation in patients with gain-of-function signal transducer and activator of transcription 1 mutations.

BACKGROUND: Gain-of-function (GOF) mutations in signal transducer and activator of transcription 1 (STAT1) cause susceptibility to a range of infections, autoimmunity, immune dysregulation, and combined immunodeficiency. Disease manifestations can be mild or severe and life-threatening. Hematopoietic stem cell transplantation (HSCT) has been used in some patients with more severe symptoms to treat and cure the disorder. However, the outcome of HSCT for this disorder is not well established. OBJECTIVE: We sought to aggregate the worldwide experience of HSCT in patients with GOF-STAT1 mutations and to assess outcomes, including donor engraftment, overall survival, graft-versus-host disease, and transplant-related complications. METHODS: Data were collected from an international cohort of 15 patients with GOF-STAT1 mutations who had undergone HSCT using a variety of conditioning regimens and donor sources. Retrospective data collection allowed the outcome of transplantation to be assessed. In vitro functional testing was performed to confirm that each of the identified STAT1 variants was in fact a GOF mutation. RESULTS: Primary donor engraftment in this cohort of 15 patients with GOF-STAT1 mutations was 74%, and overall survival was only 40%. Secondary graft failure was common (50%), and posttransplantation event-free survival was poor (10% by 100 days). A subset of patients had hemophagocytic lymphohistiocytosis before transplant, contributing to their poor outcomes. CONCLUSION: Our data indicate that HSCT for patients with GOF-STAT1 mutations is curative but has significant risk of secondary graft failure and death.