Evaluation of specificity and sensitivity of IRT/IRT protocol in the cystic fibrosis newborn screening program: 6-year experience of three tertiary centers.

We aimed to evaluate cutoff values of immunoreactive trypsinogen (IRT)/IRT and determine relationship between IRT values and clinical characteristics of children with cystic fibrosis (CF). This study is cross-sectional study. Data of children with positive newborn screening (NBS) between 2015 and 2021 were evaluated in three pediatric pulmonology centers. Age at admission, sex, gestational age, presence of history of meconium ileus, parental consanguinity, sibling with CF, and doll-like face appearance, first and second IRT values, sweat chloride test, fecal elastase, fecal fat, biochemistry results, and age at CF diagnosis were recorded. Sensitivity and specificity of IRT cutoff values were evaluated. Of 815 children with positive NBS, 58 (7.1%) children were diagnosed with CF. Median values of first and second IRT were 157.2 (103.7-247.6) and 113.0 (84.0-201.5) µg/L. IRT values used in current protocol, sensitivity was determined as 96.6%, specificity as 17.2% for first IRT, and 96.6% sensitivity, 20.5% specificity for second IRT. Positive predictive value (PPV) was determined as 7.1%. When cutoff value for first IRT was estimated as 116.7 µg/L, sensitivity was 69.0% and specificity was 69.6%, and when cutoff value was set to 88.7 µg/L for second IRT, sensitivity was 69.0% and specificity was 69.0%. Area under curve was 0.757 for first and 0.763 for second IRT (p < 0.001, p < 0.001, respectively). PPV was calculated as 4.3%.    Conclusion: Although sensitivity of CF NBS is high in our country, its PPV is significantly lower than expected from CF NBS programs. False-positive NBS results could have been overcome by revising NBS strategy. What is Known: • Although immunoreactive trypsinogen elevation is a sensitive test used in cystic fibrosis newborn screening, its specificity is low. • In countries although different algorithms are used, all strategies begin with the measurement of immunoreactive trypsinogen in dried blood spots. What is New: • In our study, it was shown that use of the IRT/IRT protocol for cystic fibrosis newborn screening is not sufficient for the cut-off values determined by the high number of patients. • Newborn screening strategy should be reviewed to reduce false positive newborn screening results.

Comparison of Clinical and Laboratory Features and Treatment Options of 237 Symptomatic and Asymptomatic Children Infected with SARS-CoV-2 in the Early Phase of the COVID-19 Pandemic in Turkey.

Little is known about the therapeutic use of hydroxychloroquine in pediatric patients with coronavirus disease 2019 (COVID-19). Here, we retrospectively retrieved data of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR-positive pediatric patients from 20 hospitals in 8 Turkish cities. We obtained epidemiological, clinical, and laboratory features of the patients, as well as the drugs used for treating COVID-19. A total of 237 nasopharyngeal swab SARS-CoV-2 PCR-positive children were included in the study from March 26, 2020 to June 20, 2020. The mean age of asymptomatic children (118 ± 62 months) was higher than that of symptomatic children (89 ± 69 months). Symptomatic children had significantly lower mean lymphocyte counts and higher mean CRP, D-dimer, procalcitonin, and LDH levels than asymptomatic children in the univariate analysis. Among 156 children, 78 (50%), 15, 44, and 21 were treated with a hydroxychloroquine-containing regimen, hydroxychloroquine + azithromycin + oseltamivir, hydroxychloroquine + azithromycin, and hydroxychloroquine alone, respectively. Among 156 patients who received medical treatment, 90 (58%) underwent pre- and/or post-treatment electrocardiogram (ECG). However, none of them had ECG abnormalities or required hydroxychloroquine discontinuation due to adverse drug reactions.