Prevalence of Common Human Coronaviruses (NL63, 229E, and OC43) in Adults before the COVID-19 Pandemic: a Single-Center Study from Turkey, 2015-2020.

Common Human Coronaviruses (HCoVs), such as NL63, HKU1, 229E, and OC43, induce respiratory tract infections worldwide. Epidemiological studies of HCoVs are of paramount importance because the disease burden and trajectory (in years) have not been well addressed in adults. Here, we aimed to describe the burden of HCoVs in a hospital setting over five years before the coronavirus disease 2019 pandemic. This was a retrospective study of patients (>18 years) between January 1, 2015, and January 1, 2020, whose respiratory specimens were tested by multiplex real-time polymerase chain reaction. In total, 7,861 respiratory samples (4,540 patients) were included, 38% of which tested positive for any respiratory virus. Of these, 212 (12.2%) samples were positive for HCoVs, and their co-infection with other respiratory viruses was 30.6%. Rhinovirus (27.6%) was the most common co-infection among all three HCoVs. The overall prevalence of HCoVs tended to be the highest in the winter (40.9%). Patients aged ≥60 years had the highest prevalence of overall HCoVs (39.7%). Given the duration and large sample size, this study from Turkey is one of the largest to date among adults in the literature. These epidemiological data and molecular surveillance of HCoVs have important implications for the control and prevention of respiratory infections.

Relative Vaccine Effectiveness of the Third Dose of CoronaVac or BNT162b2 Following a Two-Dose CoronaVac Regimen: A Prospective Observational Cohort Study from an Adult Vaccine Center in Turkey.

Coronavirus disease 2019 (COVID-19) continues to pose a threat to public health with the potential for the emergence of new variants. Vaccines are the milestones to control and slow down the damage of the pandemic. As of January 2021, a two-dose regimen with CoronaVac was authorized in Turkey. Due to the waning seroprevalence rate of SARS-CoV-2 over time, BNT162b2 or CoronaVac has been administered as the third dose following a two-dose CoronaVac regimen as a national vaccination policy. As of 14 January 2021, 5243 volunteers who received two doses of the CoronaVac vaccine at Hacettepe University Adult Vaccine Center were followed prospectively. In our study, relative vaccine effectiveness (VEff) for the third dose of the CoronaVac was 58.24% and 87.27% for BNT162b2 in preventing symptomatic COVID-19 cases. There were no hospitalizations, intensive care unit admissions, or deaths in third-dose booster groups with either BNT162b2 or CoronaVac, yielding 100% effectiveness. Both homologous or heterologous third-dose boosters provided further protection against severe COVID-19 and should be prioritized as an effective strategy to combat the COVID-19 pandemic.

Retrospective Evaluation of Hepatitis C Awareness in Turkey Through Two Decades.

BACKGROUND/AIMS: Chronic hepatitis C (CHC) is the only viral infection that can be treated with oral antiviral agents. However, CHC awareness is a major barrier to the World Health Organization's target of eliminating hepatitis C virus (HCV) by 2030. Here, CHC awareness trends were analyzed in Hacettepe University Hospital, Turkey, between January 2000 and December 2017. MATERIALS AND METHODS: Central laboratory data were retrospectively analyzed for HCV test results (anti-HCV, HCV RNA, HCV genotype). After combining 548,141 anti-HCV test results, 395,103 cases were analyzed. The following two parameters were defined for CHC awareness: (1) the presence of HCV RNA results for anti-HCV positives and (2) the presence of a genotype result for HCV RNA positives. RESULTS: Anti-HCV positives were older than negatives (mean age-years ± SD, 59.4 ± 19.0 vs. 44.0 ± 18.9), and the positivity rate was higher in women than in men (1.4% vs. 1.0%). Anti-HCV positivity decreased from 3.1% to 0.6% from 2000 to 2015 and subsequently stabilized. The overall percentage of RNA testing among anti-HCV positives was 53.1% (range, 20%-70%), which stabilized at approximately 50% after 2010. The genotyping rate for RNA positives varied between 40% and 70%. The main genotype identified was genotype 1 (85.7%). CONCLUSION: In an ideal CHC awareness state, all anti-HCV positives should undergo RNA testing, and genotyping should be performed when RNA tests are positive. However, even in our referral center, the combined rate of RNA and genotype testing was only approximately 50% during the last 10 years.

Predictive value of cytokine/chemokine responses for the disease severity and management in children and adult cases with COVID-19.

The disease course of children with coronavirus disease 2019 (COVID-19) seems milder as compared with adults, however, actual reason of the pathogenesis still remains unclear. There is a growing interest on possible relationship between pathogenicity or disease severity and biomarkers including cytokines or chemokines. We wondered whether these biomarkers could be used for the prediction of the prognosis of COVID-19 and improving our understanding on the variations between pediatric and adult cases with COVID-19. The acute phase serum levels of 25 cytokines and chemokines in the serum samples from 60 COVID-19 pediatric (n = 30) and adult cases (n = 30) including 20 severe or critically ill, 25 moderate and 15 mild patients and 30 healthy pediatric (n = 15) and adult (n = 15) volunteers were measured using commercially available fluorescent bead immunoassay and analyzed in combination with clinical data. Interferon gamma-induced protein 10 (IP-10) and macrophage inflammatory protein (MIP)-3ß levels were significantly higher in patient cohort including pediatric and adult cases with COVID-19 when compared with all healthy volunteers (p ≤ .001 in each) and whereas IP-10 levels were significantly higher in both pediatric and adult cases with severe disease course, MIP-3ß were significantly lower in healthy controls. Additionally, IP-10 is an independent predictor for disease severity, particularly in children and interleukin-6 seems a relatively good predictor for disease severity in adults. IP-10 and MIP-3ß seem good research candidates to understand severity of COVID-19 in both pediatric and adult population and to investigate possible pathophysiological mechanism of COVID-19.

[Multicenter evaluation of the indirect nitrate reductase assay for the rapid detection of multidrug-resistant tuberculosis]. / Çok ilaca dirençli tüberkülozun hizli tespiti için dolayli nitrat redüktaz testinin çok merkezli degerlendirilmesi.

Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to at least isoniazid (INH) and rifampicin (RIF), and it complicates the implementation of tuberculosis control programmes. The rapid detection of MDR-TB is crucial to reduce the transmission of disease. The nitrate reductase assay (NRA) is one of the colorimetric susceptibility test methods for rapid detection of MDR-TB and based on the ability of reduction of nitrate to nitrite by Mycobacterium tuberculosis. The aim of this study was to evaluate the performance of the NRA for the rapid detection of MDR-TB. A total of 237 M.tuberculosis complex (MTC) isolates that were identified by the same method (BD MGIT(TM) TBc Identification Test, USA) from nine different medical centers in Turkey were included in the study. The susceptibility results of the isolates against INH and RIF obtained by reference test (Bactec MGIT(TM) 960, BD, USA) were then compared with NRA. In order to ensure consistency between centers, Löwenstein-Jensen (LJ) medium with antibiotics and without antibiotics (growth control) and Griess reagent solution were prepared in a single center (Ondokuz Mayis University School of Medicine, Medical Microbiology Department) and sent to all participant centers with the standardized test procedure. After the inoculation of bacteria into the test tubes, the tubes were incubated at 37°C, and after seven days of incubation, 500 µl Griess reagent was added to the LJ medium without antibiotics. If a color change was observed, an equal volume of Griess reagent was added to test LJ media with antibiotics. When a color change was observed in LJ media with antibiotics, it was considered that the isolate was resistant to tested antibiotics. Among 237 MTC isolates, 16 were resistant only to INH and nine were resistant only to RIF; 93 isolates (39.2%) were resistant (MDR) and 119 isolates (50.2%) were susceptible to both of the drugs determined with the reference susceptibility test. In the study, five INH-resistant isolates determined with reference method were found susceptible with NRT and eight INH-susceptible isolates determined with reference method were found resistant with NRT. In contrast, one RIF-resistant isolate determined with reference method was found susceptible with NRT and three RIF-susceptible determined isolates were found resistant with NRT. Accordingly, the concordance rate between the reference method and NRA were estimated as 94.5% for INH and 98.3% for RIF. The sensitivity, specificity, positive and negative predictive values of NRA were detected as 95.4%, 93.7%, 92.8% and 96% for INH, and 99%, 97.8%, 97.1% and 99.2% for RIF, respectively. The results of the 111 isolates were obtained on the seventh day, while the rest of the results were obtained between 10-14 days. In conclusion, the data of this multicenter study showed that NRA is a reliable, relatively inexpensive and practical method to perform for the rapid detection of MDR-TB.

Alpha-1 antitrypsin deficiency in patients with chronic hepatitis.

BACKGROUND/AIMS: Alpha-1 antitrypsin deficiency causes accumulation of mutant alpha-1 antitrypsin molecules in hepatocytes, and is attributed to severe liver injury even in heterozygous state. However, there is a question as to whether alpha-1 antitrypsin deficiency is only a cause of liver injury or has a worsening effect on the underlying liver disease. We aimed to determine the role of alpha-1 antitrypsin deficiency in the ongoing chronic hepatitic process. MATERIALS AND METHODS: Fifty-four patients with the diagnosis of chronic hepatitis by liver biopsy (36 chronic hepatitis B virus, 8 chronic hepatitis C virus, 7 non-alcoholic steatohepatitis, 2 primary biliary cirrhosis, and 1 autoimmune hepatitis) and 51 age- and sex-matched control subjects chosen from among healthy blood donors were included in the study. Isoelectric focusing for identifying alpha-1 antitrypsin phenotypes was performed in all patients and control subjects, whereas the histopathological examination was done only in patients. RESULTS: Alpha-1 antitrypsin-deficient variant was absent in patients and controls. The mean serum alpha-1 antitrypsin level was significantly lower in patients (157.4 ± 33 mg/dl) than controls (134.8 ± 30 mg/dl) (p<0.00). Histological activity index and fibrosis grade in the liver were not related to the serum alpha-1 antitrypsin level (p: 0.276 and 0.902, respectively). Additionally, the serum alpha-1 antitrypsin levels among normal variants of alpha-1 antitrypsin did not differ according to the underlying liver diseases (p: 0.928). CONCLUSIONS: This prospective case-control study could not define any additional effect of alpha-1 antitrypsin deficiency on liver histopathology in chronic hepatitis patients.

Cutoff level to detect heterozygous alpha 1 antitrypsin deficiency in Turkish population.

BACKGROUND: Alpha 1 antitrypsin (AT) deficiency is a hereditary disorder leading to the defective defence system against neutrophil elastasis in lung and accumulation of insoluble heterodimer AT molecules in hepatocytes. Knowledge of the prevalence of AT deficiency in each country is important to organize the public health policy. The aim of this study is to determine the prevalence of AT deficiency in Turkish population and to define the cutoff value of AT level in serum to detect heterozygous AT deficient subjects. MATERIALS AND METHODS: Serum samples from 1,203 healthy blood donors were used, attending the Blood Bank of Hacettepe Medical Faculty. Isoelectric focusing method for determining PIM, PIS, and PIZ alleles and rate immune nephelometry for measuring the level of AT in serum were used. RESULTS: Out of 1,203 healthy blood donors enrolled, 1,164 (%96.8) had normal variant PI MM allelee, 9 (%0.7) PI MZ, 7 (%0.6) PI MS, 6 (%0.5) MF, and 17 (%1.4) PI M? (unidentified variants with existing standards). Most individuals (89.6%) with low AT level (cutoff <100 mg/dl) in serum were positive for PI MM allele. The cutoff value to investigate PI MZ was 100.5 mg/dl, which had PPV and NPV of 5.0 and 99.9%, respectively. AT deficiency is a rare hereditary disorder in asymptomatic healthy Turkish blood donors. Although the cutoff value of 100.5 mg/dl for AT level in serum was able to detect heterozygous AT deficiency in the healthy population, this finding should be conformed to case-control studies.