Very-early-onset Inflammatory Bowel Disease in an Infant with a Partial RIPK1 Deletion.

The monogenic causes of very-early-onset inflammatory bowel disease (VEO-IBD) have been defined by genetic studies, which were usually related to primary immunodeficiencies. Receptor-interacting serine/threonine-protein kinase-1 (RIPK1) protein is an important signalling molecule in inflammation and cell death pathways. Its deficiency may lead to various clinical features linked to immunodeficiency and/or inflammation, including IBD. Here, we discuss an infant with malnutrition, VEO-IBD, recurrent infections and polyathritis who has a homozygous partial deletion in RIPK1 gene.

DIAPH1-Deficiency is Associated with Major T, NK and ILC Defects in Humans.

Loss of function mutations in Diaphanous related formin 1 (DIAPH1) are associated with seizures, cortical blindness, and microcephaly syndrome (SCBMS) and are recently linked to combined immunodeficiency. However, the extent of defects in T and innate lymphoid cells (ILCs) remain unexplored. Herein, we characterized the primary T, natural killer (NK) and helper ILCs of six patients carrying two novel loss of function mutation in DIAPH1 and Jurkat cells after DIAPH1 knockdown. Mutations were identified by whole exome sequencing. T-cell immunophenotyping, proliferation, migration, cytokine signaling, survival, and NK cell cytotoxicity were studied via flow cytometry-based assays, confocal microscopy, and real-time qPCR. CD4+ T cell proteome was analyzed by mass spectrometry. p.R351* and p.R322*variants led to a significant reduction in the DIAPH1 mRNA and protein levels. DIAPH1-deficient T cells showed proliferation, activation, as well as TCR-mediated signaling defects. DIAPH1-deficient PBMCs also displayed impaired transwell migration, defective STAT5 phosphorylation in response to IL-2, IL-7 and IL-15. In vitro generation/expansion of Treg cells from naïve T cells was significantly reduced. shRNA-mediated silencing of DIAPH1 in Jurkat cells reduced DIAPH1 protein level and inhibited T cell proliferation and IL-2/STAT5 axis. Additionally, NK cells from patients had diminished cytotoxic activity, function and IL-2/STAT5 axis. Lastly, DIAPH1-deficient patients' peripheral blood contained dramatically reduced numbers of all helper ILC subsets. DIAPH1 deficiency results in major functional defects in T, NK cells and helper ILCs underlining the critical role of formin DIAPH1 in the biology of those cell subsets.

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.

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.

Evaluation of children with chronic cough including obstructive sleep apnea: a single-center experience.

Chronic cough in children may be due to a diverse range of etiologies. We aimed to evaluate children with chronic cough following a standardized cough algorithm and assess obstructive sleep apnea (OSA) as a possible etiology. In addition, cough resolution rates of two different treatment protocols in children with non-specific cough were compared. A total of 237 children referred for chronic cough were assessed and classified according to etiologies. Children with non-specific cough were assigned either in the early-arm (group-1, n = 13) or delayed arm (group-2, n = 23). The presence of OSA was evaluated using a pediatric sleep questionnaire, and polysomnography was handled in indicated patients. Asthma (n = 82) and protracted bacterial bronchitis (PBB) (n = 73) were the most frequent etiologies. Cough resolution was higher in group-1 (100%) compared with group-2 (50%) (absolute risk reduction (rr) = 43.48% [95% CI 21.38-65.58%]). Polysomnography revealed mild (n = 6), moderate (n = 7), or severe (n = 5) OSA in 18 children, with adenoid/adenotonsillary hypertrophy as the leading cause.Conclusion: We recognized asthma and PBB as the most frequent causes of chronic cough in our cohort. Early treatment of patients with high parental anxiety might be beneficial. We also believe that further studies including larger series might eventuate in incorporation of assessment of OSA to standardized algorithms. What is known? • Chronic cough in children may be due to a diverse range of etiologies, including serious respiratory disorders. Thus, its correct diagnosis and treatment are essential. • Although a well-defined reason of chronic cough in adults, obstructive sleep apnea (OSA) has not been been evaluated so far in children with chronic cough. What is new? • We examined OSA for the first time as a possible cause of chronic cough in children and detected OSA with polysomnography in cases who scored high pediatric sleep questionnaire (PSQ) scores. • We believe that studies including larger series might eventuate in incorporation of assessment of OSA to standardized algorithms for children with chronic cough.

Differential diagnosis in ulcerative colitis in an adolescent: Chronic granulomatous disease needs extra attention.

Chronic granulomatous disease (CGD) is a primary immune deficiency that is commonly diagnosed under the age of 5 years (95%) and is rarely seen in adulthood. CGD may manifest as inflammatory bowel disease (IBD) in childhood. Without proper diagnosis, these patients may be monitored for years as IBD; some may even be regarded as steroid-resistant ulcerative colitis (UC) and end up having a colectomy. In this case report, we described a patient who had been followed-up for years as UC and subsequently underwent colectomy, but was finally diagnosed in adulthood as primary immune deficiency.