Autoimmune Cytopenias Are Highly Associated with Inborn Errors of Immunity and They May Be the Initial Presentations in Cases without Severe Infections.

INTRODUCTION: Inborn errors of immunity (IEIs) are inherited disorders that present with increased susceptibility to infections as well as noninfectious complications. Due to the aberrant immune functions of patients with IEI, autoimmune cytopenia (AIC) may be the initial finding, which makes diagnosis a challenge. We aimed to evaluate the clinical course, laboratory findings, and treatment response of AIC in children with IEI. METHODS: Data of children with autoimmune hemolytic anemia (AIHA) and/or immune thrombocytopenic purpura (ITP) were obtained from a retrospective chart review of IEI patients diagnosed and followed in our center. Demographic and clinical features and therapeutic outcomes were evaluated. Immunologic findings were compared between patients with AIHA, ITP, and Evans syndrome (ES). The patients were also divided into two subgroups based on the presence or absence of immune dysregulation diseases (IDDs), and all data were compared between these two groups. RESULTS: Out of 562 patients with IEI, 6% (n: 34) had AIC which were ITP (23.5%), AIHA (35.5%), and ES (41.2%). AIC was the initial finding in 50% of these 34 patients. Patients with ES had a higher mean percentage of CD8+ T lymphocytes than ITP patients (40.77 ± 20.21% vs. 22.33 ± 12.48%, p = 0.011). Patients with IDDs were more likely to develop ES (p = 0.004), lymphoproliferation (p = 0.005), and resistance to first-line therapy (p = 0.021) than other IEI groups. CONCLUSION: This study shows that AIC may be the initial finding of IEI, particularly when lymphoproliferation and resistance to first-line therapy co-occur. Therefore, detailed investigation should be offered to all patients to avoid diagnostic delay.

Analysis of IL-1ß, TGF-ß, IL-5, ACE, PTPN22 gene polymorphisms, and gene expression levels in Turkish children with IgA vasculitis.

OBJECTIVE: Immunoglobulin-A vasculitis (IgAV) is an inflammatory disease that affects small blood vessels. This study was performed to identify an association between protein tyrosine phosphatase non-receptor type 22 (PTPN22) + 788G > A (rs33996649), transforming growth factor-beta (TGF-ß) -509C > T (rs18004069), interleukin 1-beta (IL-1ß) -511C > T (rs16944), interleukin 5 (IL-5) -746C/T (rs2069812), and angiotensin-converting enzyme (ACE) I/D (rs4646994) gene polymorphisms, susceptibility to IgAV, as well as the mRNA levels of IL-1ß, IL-1ß, and TGF-ß. METHOD: A total of 53 patients with IgAV and 50 healthy controls were enrolled. PTPN22, TGF-ß, IL-1ß, ACE gene polymorphisms, ACE gene I/D polymorphisms, and mRNA expression levels were analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, allele-specific PCR, and real-time PCR with TaqMan kits, respectively. RESULTS: PTPN22, TGF-ß, IL-1ß, IL-5, and ACE variants showed no genotype or allele differences between patients with IgAV and controls. Increased levels of IL-1ß and TGF-ß mRNA expressions were observed in patients with IgAV (p < 0.001). Patients with the IL-1ß AG genotype showed significantly increased amounts of arthritis than patients with non-AG (p = 0.004). Age at disease onset was found to be significantly different in patients with IgAV according to the presence of TGF-ß TT genotype (p = 0.047). CONCLUSION: Polymorphisms in PTPN22, TGF-ß, IL-5, IL-1ß, and ACE genes are unlikely to confer susceptibility to IgAV. However, the presence of the AG genotype of IL-1ß is associated with susceptibility to IgAV-related arthritis. This is the first study to report a significant increase in serum mRNA levels of IL-1ß and TGF-ß in IgAV patients, supporting a susceptibility to IgAV in childhood.