Person: ÖZEN, AHMET OĞUZHAN
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ÖZEN
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AHMET OĞUZHAN
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Publication Metadata only Outcome of hypogammaglobulinemia in children: Immunoglobulin levels as predictors(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2010) ÖZEN, AHMET OĞUZHAN; Ozen, Ahmet; Baris, Safa; Karakoc-Aydiner, Elif; Ozdemir, Cevdet; Bahceciler, Nerin Nadir; Barlan, Isil BeratWe evaluated 131 children (M=88, F=43) with hypogammaglobulinemia Data was analyzed mainly for delineating predictor factors for outcome The distance from the lower limit of normal (-2SD) for any single measurement of immunoglobulins (Ig) was calculated and transformed into Ig scores Mean age and duration of follow up were 5 06 +/- 4 05 and 3 7 +/- 3 03 years, respectively The diagnoses were 22 CVID, 16 IgA deficiency, 33 transient hypogammaglobulinemia of childhood (THC), 3 selective IgM deficiency and 57 unclassified hypogammaglobulinemia (UCH) Low IgA scores (<-0 124) at presentation were indicative of subsequent development of IgA deficiency or CVID, whereas low IgM score (<-0 038) pointed towards more severe and persistent phenotypes Combination of low IgM score between 2 and 5 years, impaired antibody response and low B cell counts enabled us to predict persistence of hypogammaglobulinemia beyond 5 years (specificity = 90 5% and PPV = 94 9%) and chronic lung disease (sensitivity =90 4% and specificity = 68 3%) The set of criteria including low IgM scores, impaired antibody response and low B cell counts provided a high predictive value in detecting those with persistent hypogammaglobulinemia (C) 2010 Elsevier Inc All rights reservedPublication Metadata only Osteoporosis: An ignored complication of CVID(WILEY, 2011) ÖZEN, AHMET OĞUZHAN; Baris, Safa; Ozen, Ahmet; Ercan, Hulya; Karakoc-Aydiner, Elif; Cagan, Hasret; Ozdemir, Cevdet; Barlan, Metin; Bahceciler, Nerin N.; Barlan, Isil B.Background: Multiple factors in common variable immunodeficiency (CVID) might interfere with optimal growth and maturation and potentially compromise bone health. Methods: We aimed to evaluate bone mineral density (BMD) of patients with CVID using dual energy X-ray absorptiometry (DEXA) and investigate risk factors associated with decreased bone density. Results: Twenty-two patients were included (M: 16, F: 6) with a mean age of 15.6 +/- 9.0 yr. DEXA revealed osteopenia in 6/22 (27.3%) and osteoporosis in 9/22 (40.9%) at lumbar spine and osteopenia in 7/19 (37%) and osteoporosis in 3/19 (16%) at femoral neck sites. The age of subjects with osteoporosis was significantly higher than those without (21.6 +/- 8.0 vs. 9.0 +/- 5.7 yr; p < 0.0001). BMD z-scores were significantly lower in patients with bronchiectasis compared with those without (p = 0.03). Patients with osteoporosis at femoral neck site had lower forced expiratory volume in 1 s (FEV1) (p = 0.024), FEV1/forced vital capacity (FVC) (p < 0.0001), PEF (p = 0.008), and FEF 25-75 (p = 0.013) values compared with the patients with normal BMD z-scores. Low serum 25(OH) vitamin D levels were detected in 13/22 patients and low dietary calcium intake in 17/22 patients. BMD z-scores at femoral neck were lower in patients with low B-cell percentage (p = 0.03). BMD z-score at lumbar spine was correlated with folate (r = +0.63, p = 0.004) and serum immunoglobulin G levels (r = +0.430, p = 0.04). Conclusion: Osteoporosis appeared as an emerging health problem of patients with CVID, the risk increasing with older age and poorer lung function. Nutritional, biochemical, and immunologic factors appeared to take part in decreased BMD. Insight into the mechanisms of osteoporosis in CVID is crucial to develop preventive strategies.Publication Metadata only CHAPLE disease and non-CHAPLE protein losing enteropathies: natural history and immune characteristics(2021-08-01) SELÇUK, MERVE; BARIŞ, SAFA; ÖZEN, AHMET OĞUZHAN; ÖĞÜLÜR, İSMAİL; AYDINER, ELİF; Selcuk M., Sefer A. P., Baser D., Ogulur I., Eltan S. B., Dursun E., Kocamis B., Kasap N., BARIŞ S., AYDINER E., et al.Publication Metadata only Evaluation of a Standardized Bakery Product (SUTMEK) as a Potential Tool for Baked-Milk Tolerance and Immunotherapy Research Studies(KARGER, 2019) ÖZEN, AHMET OĞUZHAN; Kiykim, Ayca; Karakoc-Aydiner, Elif; Gunes, Esra; Nain, Ercan; Ogulur, Ismail; Yazici, Duygu; Aktac, Sule; Bicer, Ayse Humeyra; Sackesen, Cansin; Baris, Safa; Ozen, AhmetBackground and Objectives: About 65-80% of children with IgE-mediated cow's milk allergy (CMA) can tolerate extensively heated milk. We have invested in the mass fabrication of a test product containing milk protein baked at 180 degrees C for 30 min (SUTMEK-milk) and a milk-free placebo (SUTMEK-placebo) to carry out a standardised double-blind placebo-controlled food challenge (DBPCFC) test in patients with CMA. Methods: We studied children with IgE-mediated CMA between 13 and 48 months of age. Specific IgEs (spIgE) to milk proteins were quantified. A DBPCFC with our bakery products was performed, and factors determining reactivity to extensively heated milk were evaluated. We also tested the applicability of SUTMEK products in baked-milk oral immunotherapy in a pilot assessment. Results: We studied 15 children (8 girls, 7 boys) with a median age of 26 months (range: 13-48 months). Nine (60%) patients tolerated a challenge with extensively heated milk, while 6 (40%) were found reactive (anaphylaxis: 2, wheezing: 2, urticaria: 2). spIgE to milk, alpha-lactalbumin, and casein, and the wheal diameter on skin prick testing were higher in the reactive group than the tolerant groups (p = 0.001, p = 0.001, p = 0.002, and p = 0.048, respectively). Receiver-operating characteristic curve analyses yielded the following cut-off values for spIgEs that would predict a reactivity to extensively heated milk; milk: 25 kU/L (area under curve, AUC: 0.981), casein: 32 kU/L (AUC: 0.983), and alpha-lactalbumin: 17 kU/L (AUC: 0.981). Nine patients have tolerated well a continued daily consumption of SUTMEK-milk or -placebo for 6 months at the desired doses. Conclusions: Our bakery products were successfully used in DBPCFC studies and qualified as an acceptable tool for use in the research of interventional tolerance induction. Although spIgE appears useful in determining children at high risk of reacting to extensively heated milk, the predictive cut-off values are still far from being perfect. (c) 2018 S. Karger AG, BaselPublication Metadata only Lymphopenia with Low T and NK Cells in a Patient with USB1 Mutation, Rare Findings in Clericuzio-Type Poikiloderma with Neutropenia(2021) ÖZEN, AHMET OĞUZHAN; Bilgic Eltan, Sevgi; Sefer, Asena Pınar; Karakus, İbrahim Serhat; Ozen, Ahmet; Karakoc-Aydiner, Elif; Baris, SafaPublication Metadata only A Novel FOXN1 Variant Is Identified in Two Siblings with Nude Severe Combined Immunodeficiency(2019) ÖZEN, AHMET OĞUZHAN; Firtina, Sinem; Cipe, Funda; Ng, Yuk Yin; Kiykim, Ayca; Ng, Ozden Hatirnaz; Sudutan, Tugce; Aydogmus, Cigdem; Baris, Safa; Ozturk, Gulyuz; Aydiner, Elif; Ozen, Ahmet; Sayitoglu, MugePublication Metadata only Could Sublingual Immunotherapy Affect Oral Health in Children with Asthma and/or Allergic Rhinitis Sensitized to House Dust Mite?(KARGER, 2017) ÖZEN, AHMET OĞUZHAN; Kiykim, Ayca; Mumcu, Gonca; Ogulur, Ismail; Karakoc-Aydiner, Elif; Direskeneli, Haner; Baris, Safa; Cagan, Hasret; Ozen, AhmetBackground: Sublingual immunotherapy (SLIT) has been successfully employed in IgE-mediated respiratory allergies. However, it is not known whether the modulation of immune responses in the sublingual area during SLIT has any deleterious effect on oral health. We sought to determine the oral health prospectively in children receiving SLIT for house dust mite allergy. Material and Methods: Eighteen children with allergic asthma and/or rhinitis and 31 agematched healthy controls (HC) were included in an openlabeled trial. Oral health was evaluated by scoring the decayed, missing, and filled teeth for primary (dmft) and permanent (DMFT) dentition, and the plaque and gingival indices. Moreover, cariogenic food intake and teeth-brushing habits were also noted at baseline and at 19 months. Results: The mean age of the SLIT participants was 9.5 +/- 3.1 years and that of the HC was 9.2 +/- 3.7 years. The mean duration of SLIT was 19.13 +/- 3.81 months. At baseline, the total dmft and DMFT indices were similar in the SLIT and HC groups (p > 0.05), which demonstrated poor hygiene overall. In the within-group comparisons at the examination at 19 months, the SLIT group had a lower number of carious primary teeth and a higher number of filled primary teeth compared to the count at baseline (p = 0.027 and p = 0.058, respectively). Conclusion: Our study showed no detrimental effect of SLIT on oral health during a period of 19 months of follow-up. Parents should be motivated to use dental health services to prevent new caries formation since our cohort had overall poor oral hygiene at the baseline. (C) 2017 S. Karger AG, BaselPublication Metadata only A Patient with Novel ICOS Mutation Presented with Progressive Loss of B Cells(2021) ÖZEN, AHMET OĞUZHAN; Sefer, Asena Pınar; Charbonnier, Louis Marie; Kasap, Nurhan; Akcam, Bengu; Demirkol, Yasemin Kendir; Eltan, Sevgi Bilgic; Ozen, Ahmet; Karakoc-Aydiner, Elif; Baris, SafaPublication Metadata only JAGN1 Deficient Severe Congenital Neutropenia: Two Cases from the Same Family(SPRINGER/PLENUM PUBLISHERS, 2015) ÖZEN, AHMET OĞUZHAN; Baris, S.; Karakoc-Aydiner, E.; Ozen, A.; Delil, K.; Kiykim, A.; Ogulur, I.; Baris, I.; Barlan, I. B.Recently autosomal recessively inherited mutations in the gene encoding Jagunal homolog 1 (JAGN1) was described as a novel disease-causing gene of severe congenital neutropenia (SCN) JAGN1-mutant neutrophils were characterized by abnormality in endoplasmic reticulum structure, absence of granules, abnormal N-glycosylation of proteins and susceptibility to apoptosis. These findings imply the role of JAGN1 in neutrophil survival. Here, we report two siblings with a homozygous mutation in JAGN1 gene, exhibiting multisystemic involvement.Publication Metadata only Basophil activation test for inhalant allergens in pediatric patients with allergic rhinitis(ELSEVIER IRELAND LTD, 2017) ÖZEN, AHMET OĞUZHAN; Ogulur, Ismail; Kiykim, Ayca; Baris, Safa; Ozen, Ahmet; Yuce, Ezgi Gizem; Karakoc-Aydiner, ElifObjective: Flow cytometric quantification of in vitro basophil activation can be quite performant and reliable tool to measure IgE-dependent allergen-specific responses in allergic patients. Current study aimed to evaluate the clinical relevance of basophil activation test (BAT) for the diagnosis of pediatric grass pollen and house dust mite (HDM) allergies. Methods: Forty-seven patients suffering from allergic rhinitis with HDM and grass pollen co sensitization with clinical history of allergic rhinitis and/or asthma and 15 non-allergic healthy subjects were enrolled. BAT was determined by flow cytometry upon double staining with anti-IgE/anti-CD63 mAb. Results: Regarding HDM with cut-off point greater than 12.5% for CD63(+) basophils sensitivity and specificity of the BAT were 90% and 73%, with positive predictive value (PPV) and negative predictive value (NPV) as 0.70 and 0.91, respectively. The analysis of concordance of being either allergic or healthy in comparison to BAT results for HDM revealed a substantial concordance (K index = 0.61, p < 0.001). Grass pollen with cut-off point greater than 11%, BAT attained a sensitivity, specificity, PPV, and NPV of 96%, 93%, 0.98, and 0.88, respectively. The analysis of concordance of being either allergic or healthy in comparison to BAT results for grass pollen revealed an almost perfect concordance (K index = 0.87, p < 0.001). Conclusion: Our findings concluded that BAT is reliable technique in the diagnosis of sensitization to grass pollen and HDM. The sensitivity of BAT in pollen allergic children was found to be remarkably higher in our cohort compared to other studies. (C) 2017 Elsevier B.V. All rights reserved.