Sabri Kemahli

PLATELET AGGREGATION IN TERM AND PRETERM NEWBORNS

The platelets of newborns have a hyporeactive period. This period, during which the platelet count is normal but their functions are deficient, is called transient platelet hyporeactivity of newborns. The platelet functions and their normalizing process of term and preterm neonates are investigated. Twenty term and 20 preterm (gestational age <37 weeks) newborns were enrolled in the study. Twenty-eight healthy children aged 2 months to 3 years old participated in the study as the control group. Healthy newborns were followed for 15 days after birth longitudinally in 3 periods: period 1 (0–4 days), period 2 (5–9 days), period 3 (10–15 days). Aggregation studies were performed from whole blood samples. Whole blood aggregation was measured by the impedance method. Transient hyporeactivity of platelets was found in term and preterm groups, and there was no difference between term and preterms. Platelets of newborns gained their normal functions at postnatal 10–14 days. The results show that hyporeactivity of platelets during the first 9 days of life is physiological and transient.

Factor V Leiden and Prothrombin Gene 20210A Variant in Neonatal Thromboembolism and in Healthy Neonates and Adults: A Study in a Single Center

This study was conducted to identify the prevalence of FV1691A and PT20210A mutations in neonates with symptomatic thromboembolism and in healthy neonates and adults. A review of 137 healthy neonates, 368 healthy adults, and 9 neonates with clinical thrombosis was done to investigate for hereditary prothrombotic mutations. For the neonates with thromboembolism, data were collected to reveal the underlying diagnosis, site of thrombosis, and associated risk factors. Investigations included screening for factor V 1691A and prothrombin 20210A. Seven of 9 neonates had one or more risk factors at the time of thromboembolism. Seventy percent (5/7) had underlying congenital thrombophilia (4/7 FV Leiden, 1/7 homozygote protein C deficiency). Among the healthy population, 11.9% of the neonates and 9% of the adults had FV1691A mutation, 4.8% of the neonates and 2.7% of the adults had PT 20210A mutation. Incidence of FV1691A mutation in the neonates with symptomatic thromboembolism was very high. The prevalence of both FV1691A and PT20210A mutations were remarkably higher than previously reported.

HBV, HCV and HIV seroprevalence among blood donors in Istanbul, Turkey: how effective are the changes in the national blood transfusion policies?

The national blood transfusion policies have been changed significantly in recent years in Turkey. The purpose of this study was to determine the prevalence of HBV, HCV, and HIV in blood donors at the Red Crescent Center in Istanbul and to evaluate the effect of changes in the national blood transfusion policies on the prevalence of these infections. The screening results of 72695 blood donations at the Red Crescent Center in Istanbul between January and December 2007 were evaluated retrospectively. HBsAg, anti-HCV, and anti-HIV-1/2 were screened by microparticle enzyme immunoassay (MEIA) method. Samples found to be positive for anti-HIV 1/2 and anti-HCV were confirmed by Inno-Lia HCV Ab III and Inno-Lia HIV I/II Score, respectively. The seropositivity rates for HBsAg, anti-HCV, and anti-HIV-1/2 were determined as 1.76%, 0.07%, and 0.008%, respectively. Compared to the previously published data from Red Crescent Centers in Turkey, it was found that HBV and HCV seroprevalances decreased and HIV seroprevalance increased in recent years. In conclusion, we believe that the drop in HBV and HCV prevalence rates are likely multifactorial and may have resulted from more diligent donor questioning upon screening, a higher level of public awareness on viral hepatitis as well as the expansion of HBV vaccination coverage in Turkey. Another factor to contribute to the decreased prevalence of HCV stems from the use of more sensitive confirmation testing on all reactive results, thereby eliminating a fair amount of false positive cases. Despite similar transmission routes, the increase in HIV prevalence in contrast to HBV and HCV may be linked to the increase in AIDS cases in Turkey in recent years.

Desferoxamine and Urinary Zinc Excretion in β-Thalassemia Major

This study has been undertaken to find out whether urinary zinc excretion, which is already increased in patients with thalassemia, is further increased by usual and high doses of desferrioxamine (DF). A total of 11 β-thalassemia major patients were included. DF infusions have been performed with doses, either 50 mg/kg or 150 mg/kg. Nine age and sex matched normal children were taken as the control group. The mean basal-Zn excretion of the patients was significantly higher than the mean Zn excretion observed in controls. No significant difference is observed between the mean Zn excretion obtained on different doses of DF. However, they are both significantly higher than the mean basal-Zn levels of the controls.

The significance of repeat testing in Turkish blood donors screened with HBV, HCV and HIV immunoassays and the importance of S/CO ratios in the interpretation of HCV/HIV screening test results and as a determinant for further confirmatory testing

The purpose of this study was to investigate the intra‐assay correlations amongst initial reactive and repeat screening results used in enzyme immunoassays (EIAs) for hepatitis B virus (HBV), hepatitis C virus (HCV) and HIV in blood donors. This study evaluated the value of using the power of the signal to cut‐off (S/CO) ratio index for confirming anti‐HCV/HIV reactive screening results, thereby touching upon the utility of S/CO indices in determining whether further confirmatory testing was necessary. Screening test results of the 72 695 blood donors were evaluated over a 1‐year period. Correlation analysis among each initial test and retests was done by Pearson r test. Appropriate S/CO values to determine the need of the confirmation testing was investigated by ROC analyses. EIA intra‐assay correlations were of statistical significance and were determined as follows: 0·948 for anti‐HCV, 0·827 for anti‐HIV and 0·948 for HBsAg. The threshold S/CO ratio values which predicted more than 95% of the confirmation test result were 3·8 for HCV and 5·6 for HIV. We were able to demonstrate a strong level of intra‐assay correlation amongst EIAs, thereby eliminating the need for repetition of the screening test. Hence, we suggest that repeat screening should only be limited to HBV and HIV tests with low EIA S/CO ratios. Thus, using the power of the S/CO ratio in determining the need for HCV confirmation testing can be a cost‐effective measure, especially if the S/CO value is ≥3·8.

Recombinant human growth hormone treatment in children with thalassemia major.

Abstract Background: To evaluate the growth hormone reserve and the growth hormone response to recombinant human growth hormone (GH) in prepubertal thalassemic children with growth retardation.

ANALYSIS OF PEDIATRIC THROMBOTIC PATIENTS IN TURKEY

This study analyzes the data of thrombotic children who were followed up in different pediatric referral centers of Turkey, to obtain more general data on the diagnosis, risk factors, management, and outcome of thrombosis in Turkish children. A simple two-page questionnaire was distributed among contact people from each center to standardize data collection. Thirteen pediatric referral centers responded to the invitation and the total number of cases was 271. All children were diagnosed with thromboembolic disease between January 1995 and October 2001. Median age at time of first thrombotic event was 7.0 years. Of the children 4% of the cases were neonates, 12% were infants less than 1 year old, and 17% were adolescents. Thromboembolic event was mostly located in the cerebral vascular system (32%), deep venous system of the limbs, femoral and iliac veins (24%), portal veins (10%), and intracardiac region (9%). Acquired risk factors were present in 86% of the children. Infection was the most common underlying risk factor. Inherited risk factors were present in 30% of the children. FVL was the most common inherited risk factor. Acquired and inherited risk factors were present simultaneously in 19% of the patients. Eleven children had a history of familial thrombosis. Due to the local treatment preferences, the treatment of the children varied greatly. Outcome of the 142 patients (52%) was reported: 88 (62%) patients had complete resolution, 47 (33%) had complications, 12 (9%) had recurrent thrombosis, and 34 (24%) died. Three children (2.1%) died as a direct consequence of their thromboembolic disease. The significant morbidity and mortality found in this study supports the need for multicentric prospective clinical trials to obtain more generalizable data on management and outcome of thrombosis in Turkish children.

Molecular pathology of haemophilia B in Turkish patients: identification of a large deletion and 33 independent point mutations.

Summary. Heterogeneous mutations in the coagulation factor IX (FIX) gene result in a bleeding tendency known as haemophilia B. The haemophilia B mutation database has a total of 2353 patient entries, including 10 of the estimated 1000 Turkish patients. In this study, a more comprehensive analysis of the molecular pathology of haemophilia B in Turkey revealed one large deletion and 33 point mutations in the FIX gene of 34 unrelated patients. Haplotype analysis using six polymorphic sites showed that the mutations identified in a total of 45 patients occurred on 13 different haplotypes and that each mutation was family specific.

Clinical Teaching and OSCE in Pediatrics

Abstract Emphasis is being given to early contact by medical students with patients, and curricula are being designed to address this trend. Although teaching of clinical skills mostly depends on the traditional “apprenticeship” model, there is insufficient supervision of students while they examine the patients. This leads to the lack of acquisition of good clinical skills and some patient-student frustrations during examination by inexperienced students. The problem is greater in pediatric departments. One way to overcome this is to observe the students while they take a history and do a physical examination and to give them feedback. On the other hand, objective structured clinical examinations (OSCEs) should be used more in pediatric examinations to make use of the steering effect such examinations have on student achievement. However, OSCEs should not be the only student assessment tool, but should be complemented by other examination methods.

Doppler Color Flow Imaging for the Evaluation of Postsplenectomy Portal Vein Thrombosis in Pediatric Hematological Diseases

Doppler color flow imaging (DCFI) is a noninvasive technique used for the clinical evaluation of hemodynamic changes in various diseases. 1 Here we report our experience on the use of DCFI for the evaluation of postsplenec-tomy portal vein thrombosis in pediatric hematological diseases.