SARS-CoV-2 seroepidemiological study in healthcare workers and discordant results using seven different diagnostic methods.

The aim of the study was to access the SARS-CoV-2 antibody seroprevalence in healthcare workers (HCWs) of a tertiary pediatric hospital after the first wave of the pandemic and to compare the results among seven commercially available antibody detection assays, including chemiluminescence (CMIA), electroluminescence (ECLIA), Εnzyme-Linked Immunosorbent Assay (ELISA), and rapid immunochromatography (RIC). SARS-CoV-2 antibody detection was performed in serum samples of 1216 HCWs, using a reference CMIA assay and 8/1216 (0.66%) were detected positive. Positive serum samples were further tested with other assays; however, only one sample was positive by all tests. The rest 7 cases were negative with ECLIA and ELISA and gave discordant results with RIC test. Six months later, new serum samples of seropositive HCWs were analyzed with the same 7 tests, with inconsistent results again. Identification of reliable SARS-CoV-2 antibody tests is important to determine the actual number of past infections, the duration of antibodies, and guide public health decisions.

Association of clinical and epidemiological characteristics with COVID-19 BNT162b2 mRNA vaccine short-term adverse reactions in healthcare workers.

INTRODUCTION: The aim of the study was to investigate the prevalence and severity of adverse reactions (ARs) after immunization of healthcare workers (HCWs) with BNT162b2 vaccine and to associate them with clinical and epidemiological characteristics. METHODS: A form containing demographic and clinical data as well as ARs after both doses of the vaccine was completed, and statistical association analysis was performed. RESULTS: A total of 502 HCWs (females 78.3%) with mean age (±SD) 48.17 years (±12.97) participated. After the first dose, 404 (80.5%) HCWs reported at least one local AR (LAR) and 366 (72.9%) after the second dose (p-value=0.004). After the first dose, 121 (24.1%) HCWs reported at least one systemic AR (SAR) and 275 (54.8%) after the second dose (p-value<0.0001).In the logistic regression analysis, there was no association of gender or medical history of underlying disease with LARs. There was a negative association of age with the cumulative score (CS) of LARs (OR: 0.82, 95% CI: 0.69-0.96) after the first dose. Females had a positive association with CS of SARs following both doses (OR, 95% CI: 2.57, 1.39-4.73 and 2.71, 1.76-4.19, respectively). Age was negatively associated with CS of SARs (OR: 0.66, 95% CI: 0.57-0.76) after the second dose. Severe ARs included Bell's palsy (1) and tinnitus with temporary hearing loss (1). CONCLUSION: The administration of the BNT162b2 vaccine in our HCWs cohort had a good safety profile with the most common ARs being self-limited. An increasing rate of SARs following the second vaccine dose was noticed. Rare but severe possible ARs should be further investigated.

Characteristics of Streptococcus pneumoniae serotype 19A isolates from children in the pre and post Conjugate Vaccine Era. Single center experience 1986-2015.

BACKGROUND: The present study assessed the prevalence and characteristics of S. pneumoniae serotype 19A isolates from children with pneumococcal disease (PD), before and since introduction of pneumococcal conjugate vaccines (PCVs) in Greece. METHODS: S. pneumoniae isolates collected at one large pediatric hospital between 1986 and 2015 were serotyped by the Quellung reaction and MICs determined by Etest. Alterations of pbp genes and the presence of mefA, mefE, ermB genes were detected by polymerase chain reaction. Genotypes were assessed by multilocus sequence typing (MLST). RESULTS: Among 1875 isolates, 210 (11.2%) belonged to serotype 19A. The prevalence of PD caused by serotype 19A increased from 4.6% in the pre-PCV7 years (1986-2005) to 19.6% in the post-PCV7 years (2006-2010), peaking at 27% in 2009 (p < 0.001, 95% CI; 2.0, 18.2) with a significant upward trend (p = 0.04, 95% CI; 1.02, 12.66). Following the introduction of PCV13 in 2010, the rate decreased from 22% in 2011 to 11.4% in 2015 (p = 0.08, 95% CI; 0.92, 5.1) with a downward trend of borderline significance (p = 0.05, 95% CI; -6.8, 0.04). The multidrug resistant (MDR) serotype 19A isolates increased from 10.6% in 1986-2005 to 21.2% in 2006-2010 and to 71.8% in 2011-2015 (P < 0.001). Alterations in pbp genes were detected in all penicillin non-susceptible isolates. Of 110 erythromycin resistant isolates, 21 contained the mefE gene, 36 the ermB and 53 both the mefE and ermB genes. MLST analysis of 142 isolates revealed four dominant clonal complexes (CC); CC320, CC172, CC276 and CC199. The majority of CC320 and CC276 isolates displayed MDR phenotypes. CONCLUSION: PD caused by serotype 19A increased significantly after the introduction of PCV7 followed by a decline after PCV13 use. The vast majority of persisting 19A isolates was MDR. Surveillance studies are necessary to monitor the changes in the pneumococcal population.

Detection of bacterial pathogens in synovial and pleural fluid with the FilmArray Blood Culture Identification System.

We report the use of FilmArray Blood Culture Identification (BCID) multiplex PCR system for pathogen detection from a child with septic arthritis that Streptococcus pyogenes was identified directly from synovial fluid and a child with complicated pneumonia with pleural effusion that Streptococcus pneumoniae was identified from pleural fluid.

A Case-Control Study on the Risk Factors for Meningococcal Disease among Children in Greece.

PURPOSE: The aim of this study was to identify environmental or genetic risk factors that are associated with invasive meningococcal disease (IMD) in children in Greece. METHODS: A case-control study was performed in 133 children (44 cases and 89 controls) aged between 0-14 years, who were hospitalized in a children's hospital in Athens. Demographics and possible risk factors were collected by the use of a structured questionnaire. To investigate the association of mannose binding lectin (MBL) with IMD, a frequency analysis of the haplotypes of the MBL2 gene and quantitative measurement of MBL serum protein levels were performed using Nanogen NanoChipR 400 technology and immuno-enzyme techniques, respectively. RESULTS: The multivariate analysis revealed that changes in a child's life setting (relocation or vacation, OR = 7.16), paternal smoking (OR = 4.51), upper respiratory tract infection within the previous month (OR = 3.04) and the density of people in the house/100m2 (OR = 3.16), were independent risk factors associated with IMD. Overall 18.8% of patients had a MBL2 genotype with low functionality compared to 10.1% of healthy controls, but this was not statistically significant (p = 0.189). CONCLUSION: Prevention strategies aimed at reducing parental smoking and other risk factors identified in this study could decrease the risk of IMD among children in Greece.

Molecular analysis of Streptococcus pyogenes macrolide resistance of paediatric isolates during a 7 year period (2007-13).

OBJECTIVES: The molecular characterization of paediatric group A Streptococcus (GAS) isolates regarding macrolide resistance and relevant emm types in Athens, Greece. METHODS: Pharyngeal and non-pharyngeal GAS isolates were collected during a 7 year period (2007-13) and examined for antibiotic susceptibility, macrolide resistance genes [mef(A), erm(A) and erm(B)] and relevant emm types. RESULTS: Overall, 20.4% (270/1324) of GAS isolates were resistant to macrolides. The macrolide resistance rate varied during the study period with a maximum rate observed in 2008 (29.57%) and a minimum rate observed in 2013 (10.95%) (P value for trend = 0.007). During the same period, consumption of macrolides was gradually reduced by 56.6%. No difference was observed in macrolide resistance between pharyngeal and non-pharyngeal isolates (P = 0.7). Among macrolide-resistant isolates, mef(A) was detected in 87 (32.2%), erm(A) in 136 (50.4%), erm(B) in 44 (16.3%) and both mef(A) and erm(A) in 3 (1.1%) isolates. The most prevalent emm types among macrolide-resistant isolates were emm77 (31.5%), emm4 (18.1%) and emm12 (10.7%). Ten emm types (77, 4, 12, 28, 1, 22, 11, 2, 44 and 89) accounted for 90.3% of macrolide-resistant isolates. emm types 4, 22, 44 and 77 were more prevalent in macrolide-resistant compared with macrolide-susceptible isolates, whereas emm types 1, 3, 5, 6, 75 and 89 were more prevalent in macrolide-susceptible compared with macrolide-resistant isolates. CONCLUSIONS: GAS macrolide resistance remained significant in our area during the study period. A substantial decline in the resistance rate was observed in the last year of the study, which may be related to reduced consumption of macrolides.

Clinical Experience with Daptomycin for the Treatment of Gram-positive Infections in Children and Adolescents.

BACKGROUND: This subgroup analysis of the European Cubicin Outcomes Registry Experience evaluated the safety and effectiveness of daptomycin in children and adolescent patients (<18 years). METHODS: Clinical outcomes at the end of therapy were assessed as success (cured or improved), failure or nonevaluable. Safety was assessed for up to 30 days post treatment. RESULTS: Eighty-one children and adolescent patients were included in this study. The most common primary infections were bacteremia (19.8%), complicated skin and soft-tissue infection (18.5%), osteomyelitis (13.6%), endocarditis (12.3%), foreign body/prosthetic infection (12.3%), uncomplicated skin and soft-tissue infection (9.9%) and other (13.6%). Daptomycin doses ranged from 4 to >10 mg/kg/day. Median duration of therapy was 12.5 (interquartile range, 7-25; mean, 16.7; standard deviation, 12.8) days. Staphylococcus aureus (46.7%) was the most commonly isolated pathogen (23.8% methicillin-resistant S. aureus). Forty-nine (60.5%) patients completed daptomycin therapy without further antibiotics, 27 (33.3%) switched to another antibiotic, 4 (4.9%) discontinued because of adverse events (AEs) and 1 (1.2%) discontinued because of other reason. Overall, 75 (92.6%; 95% confidence interval: 95.2-100.0%) patients achieved clinical success; 39 of 41 (95.1%) patients receiving daptomycin monotherapy and 36 of 40 (90.0%) patients receiving concomitant antibiotics. Six (7.4%) patients reported AEs, including 1 patient with increased blood creatine phosphokinase. Three (3.7%) patients had serious AEs; 1 (1.2%) had a serious AE possibly related to daptomycin. CONCLUSION: Daptomycin, alone or combined with other antibiotics and/or surgery, demonstrated high clinical success rates against a wide variety of infections and was well tolerated in children and adolescents.

Pneumococcal Mastoiditis in Children Before and After the Introduction of Conjugate Pneumococcal Vaccines.

OBJECTIVES: To determine whether serotype distribution and antibiotic resistance of Streptococcus pneumoniae acute mastoiditis (AM) in children have changed in the post pneumococcal conjugate vaccines (PCVs) era. METHODS: Medical records of pneumococcal AM cases, in a tertiary pediatric hospital were reviewed from January 1999 to December 2014. S. pneumoniae isolates were serotyped using the quellung reaction and tested for antibiotic susceptibility by E-test and for macrolide resistance genes by polymerase chain reaction. RESULTS: Among 334 children with AM, S. pneumoniae was isolated from 89 (26.6%) with median age 22 months (interquartile range: 12-30 months). S. pneumoniae was recovered from ear fluid (58%), mastoid specimens (35.2%) and blood (6.8%). Resistance to penicillin, erythromycin and clindamycin was 12.4%, 49.4% and 18%, respectively. Distribution of pneumococcal serotypes before (1999-2005), after the introduction of PCV7 (2006-2010) and after PCV13 (2011-2014) was found: for the PCV7 serotypes 81%, 25% and 0% (P < 0.0001), for PCV13 additional serotypes 16.3%, 70.8% and 63.6% (P < 0.0001) and for non-PCV serotypes 2.3%, 4.1% and 36.3% (P = 0.0002), respectively. Significant increase was detected for the serotype 19A after PCV7, and this trend was not changed after PCV13 (2.3%, 50% and 50%, respectively; P < 0.0001). A significant proportion of resistant isolates to penicillin (54.5%) and erythromycin (34.8%) was identified as 19A. CONCLUSIONS: After the introduction of PCV7, a significant increase of serotype 19A and replacement of PCVs serotypes was identified. After PCV13, the overall proportion of pneumococcal mastoiditis and the incidence of serotype 19A were not significantly declined. A significant proportion of resistant isolates to penicillin and erythromycin is attributed to serotype 19A.

Rotavirus Gastroenteritis in a Neonatal Unit of a Greek Tertiary Hospital: Clinical Characteristics and Genotypes.

INTRODUCTION: Rotavirus (RV) infection in neonatal age can be mild or even asymptomatic. Several studies have reported that RV is responsible for 31%-87% of pediatric nosocomial diarrhea and causes gastroenteritis outbreaks in pediatric and neonatal units. OBJECTIVES: Study clinical characteristics, genotypes and risk factors of RV infection in neonatal age. METHODS: A prospective study was conducted from April 2009 till April 2013 in the neonatal special care unit of the largest tertiary pediatric hospital of Greece. Fecal samples and epidemiological data were collected from each neonate with gastrointestinal symptoms. RV antigen was detected with a rapid immunochromatography test. RV positive samples were further genotyped with RT PCR and sequencing using specific VP7 and VP4 primers. RESULTS: Positive for RV were 126/415 samples (30.4%). Mean age of onset was 18 days. Seventy four cases (58%) were hospital acquired. Seasonality of RV infection did not differ significantly throughout the year with the exception of 4 outbreaks. Genotypes found during the study period were G4P[8] (58.7%), G1P[8] (14.7%), G12P[8] (9.3%), G3P[8] (9.3%), G12P[6] (5.3%), G9P[8] (1.3%) and G2P[4] (1.3%). RV cases presented with: diarrhea (81%), vomiting (26.2%), fever (34.9%), dehydration (28.6%), feeding intolerance (39.7%), weight loss (54%), whilst 19% of cases were asymptomatic. Comparing community with hospital acquired cases differences in clinical manifestations were found. CONCLUSIONS: Significant incidence of nosocomially transmitted RV infection in neonatal age including asymptomatic illness exists. Genotypes causing nosocomial outbreaks are not different from community strains. Circulating vaccines can be effective in prevention of nosocomial RV infection through herd immunity.

Clinical Applications of Procalcitonin in Pediatrics: An Advanced Biomarker for Inflammation and Infection-Can It Also Be Used in Trauma?

Background. Procalcitonin is a small molecular peptide that has gained increased support as an adjunct diagnostic marker of infection in the adult population; the concordant body of evidence for the use of procalcitonin in pediatric populations is far less complete. Objectives. Our objective is to review the current evidence supporting the utilization of procalcitonin in children in a variety of clinical scenarios including SIRS, sepsis, burns, and trauma and to identify existing knowledge gaps. Methods. A thorough review of the literature was performed utilizing PubMed. We focused on using meta-analysis from adult populations to review current practices in interpretation and methodology and find concordant pediatric studies to determine if the same applications are validated in pediatric populations. Results. Current evidence supports the usage of procalcitonin as both a sensitive and a specific marker for the differentiation of systemic inflammatory response syndrome from sepsis in pediatrics with increased diagnostic accuracy compared to commonly used biomarkers including complete blood counts and C-reactive protein. Conclusions. Although the body of evidence is limited, initial observations suggest that procalcitonin can be used in pediatric trauma and burn patients as both a prognostic and a diagnostic marker, aiding in the identification of infection in patients with extensive underlying inflammation.

Human papillomavirus (HPV) genotyping of cutaneous warts in Greek children.

The human papillomavirus (HPV) infects the squamous epithelium of the skin and produces common warts, plantar warts, and flat warts, which occur commonly on the hands, face, and feet. The objective of this study was to determine the presence of HPV in warts in children in order to associate the virus with the disease. Sixty-eight children with clinically diagnosed cutaneous warts were recruited. Skin biopsy samples were examined and DNA was extracted using a commercially available kit. To distinguish between the HPV types, we used a specific pair of primers to amplify the HPV DNA. Polymerase chain reaction amplification of the L1 region was followed by restriction fragment length polymorphism analysis and Luminex xMAP technology. HPV 57 was the predominant type in our study, although the detection of the high-risk HPV type 16 in 33% of our positive samples indicates the presence of mucosal high-risk HPV types in the skin of children. It seems that the newly introduced Luminex assay maximized the discrimination of genotypes even in the case of multiple HPV infections. Or findings also suggest the presence of high-risk HPV types in cutaneous warts.

Teeth and tongue discoloration after linezolid treatment in children.

We describe 3 children who developed teeth and tongue discoloration while receiving intravenous linezolid for 2 to 3 weeks. Linezolid was coadministered with piperacillin-tazobactam or meropenem. Teeth and tongue discoloration was reversible with dental cleaning after discontinuation of linezolid. We review the published pediatric and adult cases regarding teeth and tongue discoloration after linezolid administration.

Pasteurella multocida Infection in a neonate: evidence for a human-to-human horizontal transmission.

Pasteurella multocida is usually transmitted by animal contact; however, in a significant proportion of cases, no animal exposure can be identified. Although vertical transmission has been identified in neonates, horizontal human-to-human spread has not been documented. A case of neonatal sepsis and meningitis resulting from horizontal transmission of P. multocida is described.

Respiratory viruses involved in influenza-like illness in a Greek pediatric population during the winter period of the years 2005-2008.

Viruses are the major cause of pediatric respiratory tract infection and yet many suspected cases of illness remain uncharacterized. This study aimed to determine the distribution of several respiratory viruses in children diagnosed as having influenza-like illness, over the winter period of 2005-2008. Molecular assays including conventional and real time PCR protocols, were employed to screen respiratory specimens, collected by clinicians of the Influenza sentinel system and of outpatient pediatric clinics, for identification of several respiratory viruses. Of 1,272 specimens tested, 814 (64%) were positive for at least one virus and included 387 influenza viruses, 160 rhinoviruses, 155 respiratory syncytial viruses, 95 adenoviruses, 81 bocaviruses, 47 parainfluenza viruses, 44 metapneumoviruses, and 30 coronaviruses. Simultaneous presence of two or three viruses was observed in 173 of the above positive cases, 21% of which included influenza virus and rhinovirus. The majority of positive cases occurred during January and February. Influenza virus predominated in children older than 1 year old, with type B being the dominant type for the first season and subtypes A/H3N2 and A/H1N1 the following two winter seasons, respectively. Respiratory syncytial virus prevailed in children younger than 2 years old, with subtypes A and B alternating from year to year. This is the most comprehensive study of the epidemiology of respiratory viruses in Greece, indicating influenza, rhinovirus and respiratory syncytial virus as major contributors to influenza-like illness in children.

Evaluation of potential medical and economic benefits of universal rotavirus vaccination in Greece.

AIM: To evaluate the potential benefits of introducing universal rotavirus (RV) vaccination in Greece. METHODS: A decision analytic model was developed to compare the burden and cost of rotavirus gastroenteritis (RVGE) with and without a universal RV vaccination (88% vaccination coverage) for a cohort of children followed from birth until the age of five. RESULTS: Universal RV vaccination would substantially decrease the RVGE burden on the National Health System by reducing RVGE-related hospitalizations/emergency visits and medical consultations by 83% and 75%, respectively. Total RVGE-related costs was estimated at about 7.6 M€ and would be reduced by 5.9 M€ (-78%) if RV vaccination was introduced. A rapid effect is expected with 76% of cases and 84% of costs avoided would be averted within 2 years postvaccine introduction. The societal benefit would also be significant: total annual number of RVGE cases and parent's lost work days would be reduced by 67% and 78%, respectively. Including indirect costs, the total disease cost reduction would be 9 M€. CONCLUSION: Introduction of universal RV vaccination in Greece could offer considerable medical and economic benefits for the National Health System and society. Potential herd immunity would improve results in favour of vaccination.

Frequency, clinical characteristics, and genotype distribution of rotavirus gastroenteritis in Greece (2007-2008).

Rotavirus is the leading cause of acute gastroenteritis among young children worldwide. A prospective multi-center study was conducted (2007-2008) in five Pediatric Hospitals to determine the prevalence, the clinical characteristics, and genotype distribution of rotavirus infection in Greece. Faecal samples were examined for the presence of group A rotavirus antigen by immunochromatography. Rotavirus strains were subjected to G and P genotyping by reverse-transcriptase polymerase chain reaction (PCR) and sequencing. A total of 393 children (216 boys) of median age 23 months, participated in the study. Rotavirus was the cause of acute gastroenteritis in 166 children, 42.3% (CI 95%, 37.4-47.1%) of non-hospitalized and 47.8% (CI 95%, 41.7-53.9%) of hospitalized patients. Rotavirus gastroenteritis occurred between December and April in 78.6% of the cases. Most children with RVG (77.8%) were between 3 months and 3 years old. The mean value of Clark severity score was 12.9 ± 5.1 for RVG and 10.5 ± 4.9 for non-RVG (P < 0.01). Genotypes were determined in 117 strains and their distribution was as following: G1P[8], 49%; G2P[4], 31%; G4P[8], 10%; G9P[8], 9%; and G8P[14], 1%. In conclusion, rotavirus is a frequent cause of acute gastroenteritis in Greece. The genotypes circulating are similar with those of other European countries.

Inflammatory bowel disease in children: the role of a positive family history.

OBJECTIVES: The aim of this study was to evaluate any potential influence of a family history of inflammatory bowel disease (IBD) on the clinical phenotypes and the course of IBD in children. METHODS: In this retrospective study, the notes of 411 children with the diagnosis of IBD, 244 (59.4%) with ulcerative colitis, 129 (31.4%) with Crohn's disease and 38 (9.2%) with IBD unclassified, who were admitted to our department between 1 January 1981 and 31 December 2007 were reviewed. The aim was to assess the prevalence of familial IBD and its impact on the age of disease onset, clinical phenotypes according to the Montreal classification, course and outcome of disease. The control group consisted of IBD children without a family history of IBD, who were admitted to the hospital during the same time period. RESULTS: Thirty five (8.5%) children had a family history of IBD, (ulcerative colitis 6.6%, Crohn's disease 10.9% and IBD unclassified 13.2%). Sixty-eight percent of the 22 pairs of first-degree relatives were concordant for the clinical phenotype of disease. Significantly, more children with familial IBD had symptom onset and/or disease diagnosis before 5 years of age compared with sporadic IBD (P = 0.01 and P = 0.014, respectively); however, no differences were seen in sex, clinical phenotypes, need for aggressive treatment and/or surgery. CONCLUSION: Children with familial IBD had earlier onset of disease compared with those with sporadic IBD. However, this had no significant impact on the clinical phenotypes, the course and/or the outcome of disease.

Febrile seizures and primary human herpesvirus 6 infection.

Primary human herpesvirus 6 infection is acquired mainly during the first two years of life and is often associated with febrile seizures. The aim of the present study was to investigate in Greece the frequency and clinical characteristics of primary human herpesvirus 6 (HHV-6) infection in hospitalized children with febrile seizures. Children aged from 6 months to 5 years without known neurologic disease were examined for primary HHV-6 infection, by real-time polymerase chain reaction in acute-phase plasma and by indirect immunofluorescent assay for antibody titers in acute and convalescent serum. Of 65 children included in the analysis, 55 experienced the first febrile episode of seizures and 10 the second. Primary HHV-6 infection was verified in 10 of 55 children with a first febrile episode (18%), whereas none of the 10 children with a second episode of seizures had primary HHV-6 infection. Eight children were infected with HHV-6 type B and two with type A. None of the 85 control subjects had primary HHV-6 infection, but 49% had immunoglobulin G antibodies against the virus. These findings suggest that primary HHV-6 infection is frequently associated with febrile seizures in children in this geographic region and should be considered, especially for a first episode of febrile seizures.