Hypomorphic RAG deficiency: impact of disease burden on survival and thymic recovery argues for early diagnosis and HSCT.

Patients with hypomorphic mutations in the RAG1 or RAG2 gene present with either Omenn syndrome or atypical combined immunodeficiency with a wide phenotypic range. Hematopoietic stem cell transplantation (HSCT) is potentially curative, but data are scarce. We report on a worldwide cohort of 60 patients with hypomorphic RAG variants who underwent HSCT, 78% of whom experienced infections (29% active at HSCT), 72% had autoimmunity, and 18% had granulomas pretransplant. These complications are frequently associated with organ damage. Eight individuals (13%) were diagnosed by newborn screening or family history. HSCT was performed at a median of 3.4 years (range 0.3-42.9 years) from matched unrelated donors, matched sibling or matched family donors, or mismatched donors in 48%, 22%, and 30% of the patients, respectively. Grafts were T-cell depleted in 15 cases (25%). Overall survival at 1 and 4 years was 77.5% and 67.5% (median follow-up of 39 months). Infection was the main cause of death. In univariable analysis, active infection, organ damage pre-HSCT, T-cell depletion of the graft, and transplant from a mismatched family donor were predictive of worse outcome, whereas organ damage and T-cell depletion remained significant in multivariable analysis (hazard ratio [HR] = 6.01, HR = 8.46, respectively). All patients diagnosed by newborn screening or family history survived. Cumulative incidences of acute and chronic graft-versus-host disease were 35% and 22%, respectively. Cumulative incidences of new-onset autoimmunity was 15%. Immune reconstitution, particularly recovery of naïve CD4+ T cells, was faster and more robust in patients transplanted before 3.5 years of age, and without organ damage. These findings support the indication for early transplantation.

New αIIbß3 variants in 28 Turkish Glanzmann patients; structural hypothesis for complex activation by residues variations in I-EGF domains.

Glanzmann thrombasthenia (GT) is a rare autosomal recessive bleeding disorder characterized by impaired platelet aggregation due to defects in integrin αIIbß3, a fibrinogen receptor. Platelet phenotypes and allelic variations in 28 Turkish GT patients are reported. Platelets αIIbß3 expression was evaluated by flow cytometry. Sequence analyzes of ITGA2B and ITGB3 genes allowed identifying nine variants. Non-sense variation effect on αIIbß3 expression was studied by using transfected cell lines. 3D molecular dynamics (MDs) simulations allowed characterizing structural alterations. Five new alleles were described. αIIb:p.Gly423Asp, p.Asp560Ala and p.Tyr784Cys substitutions impaired αIIbß3 expression. The αIIb:p.Gly128Val substitution allowed normal expression; however, the corresponding NM_000419.3:c.476G>T variation would create a cryptic donor splicing site altering mRNA processing. The ß3:p.Gly540Asp substitution allowed αIIbß3 expression in HEK-293 cells but induced its constitutive activation likely by impairing αIIb and ß3 legs interaction. The substitution alters the ß3 I-EGF-3 domain flexibility as shown by MDs simulations. GT variations are mostly unique although the NM_000419.3:c.1752 + 2 T > C and NM_000212.2:c.1697 G > A variations identified in 4 and 8 families, respectively, might be a current cause of GT in Turkey. MD simulations suggested how some subtle structural variations in the ß3 I-EGF domains might induce constitutive activation of αIIbß3 without altering the global domain structure.

CLINICAL FEATURES AND GENETIC ANALYSIS OF SIX PATIENTS WITH WISKOTT-ALDRICH SYNDROME REPORTING TWO NOVEL MUTATIONS: EXPERIENCE OF ERCIYES UNIVERSITY, KAYSERI, TURKEY.

AIM: The Wiskott-Aldrich syndrome (WAS) is an X-linked immunodeficiency characterized by micro-thrombocytopenia, eczema, and recurrent infections. We aimed to share our experience with six children with WAS, including two patients with two novel mutations. MATERIAL AND METHOD: We present phenotypical and laboratory description of six patients with WAS. The initial clinical presentation, biochemical and radiological features, molecular diagnosis together with long-term follow-up data are provided. RESULTS: The patients showed increased serum levels of IgE; otherwise the serum levels of IgM were decreased. The percentages of CD3+ T cells were decreased or within lower limit. Four patients underwent molecular genetics analysis and Western blot studies; two of them showed unpublished mutations: a hemizygous splice site mutation in intron 8 (c.778-2A>T), and a hemizygous deletion in exon10 of the WASP gene (c.1017delT; p.S339fsX444) were detected. Western blot studies confirmed the reduced WAS protein expression in peripheral mononuclear blood cells in four studied patients. CONCLUSIONS: The major characteristics of patients were thrombocytopenia with decreased mean platelet volume and bleeding. All patients had been previously misdiagnosed as idiopathic thrombocytopenic purpura, demonstrating the importance of a careful differential diagnosis, and intense evaluation.

PARTIAL OCULOCUTANEOUS ALBINISM AND IMMUNODEFICIENCY SYNDROMES: TEN YEARS EXPERIENCE FROM A SINGLE CENTER IN TURKEY.

BACKGROUND AND AIM: Partial oculocutaneous albinism and immunodeficiency (OCA-ID) diseases are autosomal recessive syndromes characterized by partial hypopigmentation and recurrent infections. Moreover, some OCA-ID syndromes confer susceptibility to develop a life-threatening hyperinflammatory condition called hemophagocytic lymphohistiocytosis (HLH). We investigated the genetic, clinical and immunological characteristics of 20 OCA patients. MATERIAL AND METHODS: Herein, we present the clinical and immunological characteristics of 20 OCA patients who referred to the Department of Pediatric Immunology, Erciyes University Medical Faculty in Kayseri, Turkey between 2004 and 2014. RESULTS: Of the 20 OCA patients, 7 fulfilled diagnostic criteria for HLH, 9 showed defective functions of CD8 T cells and natural killer cells, and 8 received a definitive molecular diagnosis. Among the patients, we also report a patient diagnosed with two different genetic defects, in TYR and JAK3 genes, causing, respectively, OCA and ID. CONCLUSION: Our results illustrate the variability of clinical presentations and disease severity in OCA-ID patients, with consequent challenges in diagnosing and treating these patients.

Is pentoxifylline therapy effective for the treatment of acute rheumatic carditis? A pilot study.

OBJECTIVE: The aim of the present study was to determine whether pentoxifylline has a beneficial effect on the treatment of rheumatic carditis. METHODS: A total of 33 children between the ages 6 and 16 were studied in two groups. The first group (5 boys, 10 girls, mean age: 12.2 +/- 2.9 years) was treated with steroid plus pentoxifylline and the second group (6 boys, 12 girls, mean age; 11.6 +/- 2.8 years) was treated with steroid only for 3-6 weeks until the acute-phase reactants became normal. At admission and on the 7th, 30th, and 90th days of the treatment, laboratory studies including white blood cell count, erythrocyte sedimentation rate, C-reactive protein, throat culture and cytokines (interleukin-1alpha, tumour necrosis factor-alpha) were performed. Cardiac evaluation with chest X-ray, electrocardiography and echocardiography was performed in all patients. In the control group (12 boys, 3 girls, mean age; 10.7 +/- 3.2 years) all parameters were evaluated once only. RESULTS: In both groups, the similar white blood cell count was significantly decreased on the 90th day, and there was no significant difference between the two groups. C-reactive protein, erythrocyte sedimentation rate and interleukin-1alpha were significantly decreased on the 30th and 90th days. In the first group (treated with steroid plus pentoxifylline), the cardiothoracic index was significantly greater at the beginning of the therapy. In the first group, tumour necrosis factor-alpha became normal on the 30th day and in the second group, tumour necrosis factor-alpha became normal on the 7th day of therapy. For all parameters, there was no significant difference between the two groups with respect to the type of therapy used. CONCLUSION: The present study showed that pentoxifylline plus steroid treatment has no beneficial effects on the treatment of acute rheumatic carditis when compared with steroid alone.