Impact of Genotype, Serum Bile Acids, and Surgical Biliary Diversion on Native Liver Survival in FIC1 Deficiency.

BACKGROUND AND AIMS: Mutations in ATPase phospholipid transporting 8B1 (ATP8B1) can lead to familial intrahepatic cholestasis type 1 (FIC1) deficiency, or progressive familial intrahepatic cholestasis type 1. The rarity of FIC1 deficiency has largely prevented a detailed analysis of its natural history, effects of predicted protein truncating mutations (PPTMs), and possible associations of serum bile acid (sBA) concentrations and surgical biliary diversion (SBD) with long-term outcome. We aimed to provide insights by using the largest genetically defined cohort of patients with FIC1 deficiency to date. APPROACH AND RESULTS: This multicenter, combined retrospective and prospective study included 130 patients with compound heterozygous or homozygous predicted pathogenic ATP8B1 variants. Patients were categorized according to the number of PPTMs (i.e., splice site, frameshift due to deletion or insertion, nonsense, duplication), FIC1-A (n = 67; no PPTMs), FIC1-B (n = 29; one PPTM), or FIC1-C (n = 34; two PPTMs). Survival analysis showed an overall native liver survival (NLS) of 44% at age 18 years. NLS was comparable among FIC1-A, FIC1-B, and FIC1-C (% NLS at age 10 years: 67%, 41%, and 59%, respectively; P = 0.12), despite FIC1-C undergoing SBD less often (% SBD at age 10 years: 65%, 57%, and 45%, respectively; P = 0.03). sBAs at presentation were negatively associated with NLS (NLS at age 10 years, sBAs < 194 µmol/L: 49% vs. sBAs ≥ 194 µmol/L: 15%; P = 0.03). SBD decreased sBAs (230 [125-282] to 74 [11-177] µmol/L; P = 0.005). SBD (HR 0.55, 95% CI 0.28-1.03, P = 0.06) and post-SBD sBA concentrations < 65 µmol/L (P = 0.05) tended to be associated with improved NLS. CONCLUSIONS: Less than half of patients with FIC1 deficiency reach adulthood with native liver. The number of PPTMs did not associate with the natural history or prognosis of FIC1 deficiency. sBA concentrations at initial presentation and after SBD provide limited prognostic information on long-term NLS.

SNPs of the IFNL favour spontaneous clearance of HCV infection in children.

BACKGROUND: Both spontaneous and treatment-induced clearance of hepatitis C virus (HCV) in adults have been associated with genetic polymorphisms in the interferon-λ genes. The aim of the present study was to confirm the association between the rs12979860 and evaluate the association between the rs368234815 and the rs4803217 single-nucleotide polymorphisms (SNPs) of the interferon-λ genes and the outcome of the infection in children. METHODS: Alleles and genotypes frequencies of 32 children, who presented spontaneous clearance of the virus and 135 children, with viral persistence were compared with ethnically matched controls obtained from the 1000 Genomes Project and the International HapMap Project databases. RESULTS: The frequencies of the C/C genotype of rs12979860, the TT/TT of the rs368234815 and the A/C of the rs4803217 were higher in the clearance group than in children with viral persistence (C/C versus T/T + C/T odds ratio (OR): 2.6; 90% confidence intervals (CI): 1.3-5; p = 0.01; TT/TT versus ΔG/TT + ΔG/ΔG OR: 2.8; 90% CI: 1.4-5.5; p = 0.01; and A/A versus A/C OR: 8.3; 90% CI: 1.5-45.9; p = 0.017, respectively) and with the ethnically matched controls. CONCLUSIONS: The rs12979860, the rs368234815 and the rs4803217 SNPs are associated with spontaneous clearance of HCV in children. IMPACT: Innate immune system response has a key role in the outcome of vertically acquired HCV infection in children. The rs12979860, the rs368234815 and the rs4803217 SNPs are associated with spontaneous clearance of HCV in children. Interferons-λ activate the Janus kinase-Stat pathway, which in turn induces several interferon-stimulated genes, leading to suppression of HCV replication both in vivo and in vitro.

NBAS Variants Are Associated with Quantitative and Qualitative NK and B Cell Deficiency.

PURPOSE: Biallelic pathogenic NBAS variants manifest as a multisystem disorder with heterogeneous clinical phenotypes such as recurrent acute liver failure, growth retardation, and susceptibility to infections. This study explores how NBAS-associated disease affects cells of the innate and adaptive immune system. METHODS: Clinical and laboratory parameters were combined with functional multi-parametric immunophenotyping methods in fifteen NBAS-deficient patients to discover possible alterations in their immune system. RESULTS: Our study revealed reduced absolute numbers of mature CD56dim natural killer (NK) cells. Notably, the residual NK cell population in NBAS-deficient patients exerted a lower potential for activation and degranulation in response to K562 target cells, suggesting an NK cell-intrinsic role for NBAS in the release of cytotoxic granules. NBAS-deficient NK cell activation and degranulation was normalized upon pre-activation by IL-2 in vitro, suggesting that functional impairment was reversible. In addition, we observed a reduced number of naïve B cells in the peripheral blood associated with hypogammaglobulinemia. CONCLUSION: In summary, we demonstrate that pathogenic biallelic variants in NBAS are associated with dysfunctional NK cells as well as impaired adaptive humoral immunity.

Efficacy of Sofosbuvir/Ledipasvir in Adolescents With Chronic Hepatitis C Genotypes 1, 3, and 4: A Real-world Study.

OBJECTIVES: Sofosbuvir/Ledipasvir (SOF/LDV) has been approved by the European Medicine Agency (EMA) for the treatment of children and adolescents (at least 3 years of age) with chronic hepatitis C (CHC) genotype 1, 3, and 4 infection. The aim of this study was to evaluate the efficacy and safety of SOF/LDV in adolescents (12 to <18 years old) with CHC in the real-world setting. METHODS: Prospective, open-label, multicentre study involving 12 Italian centres. Patients received the fixed-dose combination of SOF/LDV (400/90 mg) once daily ± ribavirin as per EMA approval and recommendations. The key efficacy endpoint was sustained virological response 12 weeks after the end of treatment (SVR12) as per intention-to-treat analysis. Safety was assessed by adverse events and clinical/laboratory data. RESULTS: Seventy-eight consecutive adolescents (median age 15.2 years, range 12-17.9; girls 53.8%) were enrolled and treated between June 2018 and December 2019. Genotype distribution was as follows: genotype 1 (82.1%), 3 (2.5%), and 4 (15.4%). Seventy-six (97.4%) patients completed treatment and follow-up. Overall, SVR12 was 98.7%. One patient was lost to follow-up after 4 weeks of treatment; 1 patient completed treatment and missed the follow-up visit. No virological breakthrough or relapse were observed. No patient experienced grade 3 to 4 adverse event or serious adverse event. CONCLUSIONS: The results of this real-world study confirmed the high efficacy and the optimal safety profile of SOF/LDV for treatment of CHC in adolescents.

Genotype correlates with the natural history of severe bile salt export pump deficiency.

BACKGROUND & AIMS: Mutations in ABCB11 can cause deficiency of the bile salt export pump (BSEP), leading to cholestasis and end-stage liver disease. Owing to the rarity of the disease, the associations between genotype and natural history, or outcomes following surgical biliary diversion (SBD), remain elusive. We aimed to determine these associations by assembling the largest genetically defined cohort of patients with severe BSEP deficiency to date. METHODS: This multicentre, retrospective cohort study included 264 patients with homozygous or compound heterozygous pathological ABCB11 mutations. Patients were categorized according to genotypic severity (BSEP1, BSEP2, BSEP3). The predicted residual BSEP transport function decreased with each category. RESULTS: Genotype severity was strongly associated with native liver survival (NLS, BSEP1 median 20.4 years; BSEP2, 7.0 years; BSEP3, 3.5 years; p <0.001). At 15 years of age, the proportion of patients with hepatocellular carcinoma was 4% in BSEP1, 7% in BSEP2 and 34% in BSEP3 (p = 0.001). SBD was associated with significantly increased NLS (hazard ratio 0.50; 95% CI 0.27-0.94: p = 0.03) in BSEP1 and BSEP2. A serum bile acid concentration below 102 µmol/L or a decrease of at least 75%, each shortly after SBD, reliably predicted NLS of ≥15 years following SBD (each p <0.001). CONCLUSIONS: The genotype of severe BSEP deficiency strongly predicts long-term NLS, the risk of developing hepatocellular carcinoma, and the chance that SBD will increase NLS. Serum bile acid parameters shortly after SBD can predict long-term NLS. LAY SUMMARY: This study presents data from the largest genetically defined cohort of patients with severe bile salt export pump deficiency to date. The genotype of patients with severe bile salt export pump deficiency is associated with clinical outcomes and the success of therapeutic interventions. Therefore, genotypic data should be used to guide personalized clinical care throughout childhood and adulthood in patients with this disease.

Chronic hepatitis B in children, report of a single-centre longitudinal study on 152 children.

The aims of this prospective study were as follows: (1) to describe the natural history of chronic hepatitis B virus (HBV) infection in a large cohort of untreated children followed at a single centre and (2) to evaluate whether or not the new European Association for the Study of Liver (EASL) classification for the phases of HBV infection in adults can be used for children. All children who presented at the Liver Unit of our hospital from 1 January 1987 to 31 December 2019 and were diagnosed with chronic HBV infection were enrolled. The final sample consisted of 152 children. The median duration of the follow-up was 83 months (range 7-232). At baseline, 125 patients (82.2%) were HBeAg positive (85.3% abnormal alanine aminotransferase (ALT) levels), and 24 (15.8%) were HBeAg-negative (93.3% abnormal ALT). At the end of the observation period, 62 of the HBeAg-positive patients (40.7%) achieved HBeAg seroconversion (median age 9.45 years, range 0.8-19) and 2 (1.4%) achieved HBsAg seroconversion. Elevated ALT serum levels at baseline (P = .011), lower baseline HBV DNA levels (P < .001) and Asian ethnicity (P = .0001) were identified as predisposing factors towards HBeAg seroconversion. EASL criteria could not be applied to 43.3% and 43.5% of the children at baseline and at end of observation, respectively, that were grouped into an undetermined phenotype category. According to the results of the present study, the new EASL guidelines for adults with HBV infection cannot be applied in a satisfactory manner in children.

Treatment and monitoring of children with chronic hepatitis C in the Pre-DAA era: A European survey of 38 paediatric specialists.

The burden of paediatric Hepatitis C virus (HCV) infection across Europe is unknown, as are current policies regarding monitoring and treatment. This collaborative study aimed to collect aggregate data to characterise the population of ≤18-year-olds with HCV infection in specialist follow up in a 12-month period (2016) across the PENTAHep European consortium, and investigate current policies around monitoring and treatment. A cross-sectional, web-based survey was distributed in April 2017 to 50 paediatricians in 19 European countries, covering patients' profile, and monitoring and treatment practices. Responses were received from 38/50 clinicians collectively caring for 663 children with chronic HCV infection of whom three-quarters were aged ≥6 years and 90% vertically infected. HCV genotype 1 was the most common (n 380; 57.3%), followed by genotype 3, 4 and 2. Seventeen children (3%) with chronic HCV infection were diagnosed with cirrhosis, and six were reported to have received liver transplantation for HCV-related liver disease. The majority (n 425; 64.1%) of the European children with HCV infection remained treatment-naive in 2016. Age affected clinicians' attitudes towards treatment; 94% reported being willing to use direct-acting antivirals, if available, in adolescents (aged ≥11 years), 78% in children aged 6-10 and 42% in those 3-5 years of age (Pearson correlation coefficient -0.98; P 0.0001). This survey provides the largest characterisation of the population of children in clinical follow-up for chronic HCV infection in Europe, alongside important contextual information on their management and treatment. Discussion is needed around strategies and criteria for use of direct-acting antivirals in these children.

Shortened 8-Week Course of Sofosbuvir/Ledipasvir Therapy in Adolescents With Chronic Hepatitis C Infection.

Treatment-naïve, noncirrhotic adults with chronic hepatitis C virus genotype 1 infection and with viremia levels <6 million IU/mL could be effectively treated with sofosbuvir/ledipasvir for 8 weeks. The aim of this pilot, prospective, open-label, multicenter study was to evaluate the efficacy and safety of this shortened treatment course in adolescents (≥12 years). The efficacy endpoint was sustained virological response 12 weeks after the end of treatment. Safety was assessed by adverse events and clinical/laboratory data. Fourteen consecutive adolescents (median age 16.5 years, Q1 14.1-Q3 17.4; female 57.1%), vertically infected, were enrolled and treated (June 2018-January 2019). Overall, the end of treatment response and sustained virological response 12 weeks after the end of treatment were 100%. No grade 3 to 4 adverse event or a serious adverse event was observed. Further studies are needed to confirm the optimal efficacy of the shortened 8-week treatment with sofosbuvir/ledipasvir for treatment-naïve, noncirrhotic adolescents with chronic hepatitis C virus genotype 1 infection and pretreatment viremia level < 6 million IU/mL.

Underestimation of Invasive Meningococcal Disease in Italy.

Knowing the incidence of invasive meningococcal disease (IMD) is essential for planning appropriate vaccination policies. However, IMD may be underestimated because of misdiagnosis or insufficiently sensitive laboratory methods. Using a national molecular surveillance register, we assessed the number of cases misdiagnosed and diagnoses obtained postmortem with real-time PCR (rPCR), and we compared sensitivity of rPCR versus culture-based testing. A total of 222 IMD cases were identified: 11 (42%) of 26 fatal cases had been misdiagnosed or undiagnosed and were reclassified as IMD after rPCR showed meningococcal DNA in all available specimens taken postmortem. Of the samples tested with both rPCR and culture, 58% were diagnosed by using rPCR alone. The underestimation factor associated with the use of culture alone was 3.28. In countries such as Italy, where rPCR is in limited use, IMD incidence may be largely underestimated; thus, assessments of benefits of meningococcal vaccination may be prone to error.

Hepatitis C in Children Co-infected With Human Immunodeficiency Virus.

OBJECTIVES: The objective of this systematic review was to summarize evidence regarding hepatitis C in hepatitis C virus/human immunodeficiency virus (HCV/HIV)-co-infected children focusing on mother-to-child transmission, clinical and laboratory features, outcome, and therapies. METHODS: A literature search was performed using multiple keywords and standardized terminology in MEDLINE, EMBASE, and Cochrane databases dating back to their inception up to April 1, 2015, using the following terms hepatitis C virus, HIV, and child. RESULTS: Fifty-five of 367 publications were selected for inclusion. In co-infected children, HIV impacted all the different aspects of HCV infection. Maternal HIV infection increased the risk of vertical transmission of hepatitis C. Children with HCV/HIV co-infection presented a lower rate of spontaneous clearance of HCV, were more commonly HCV viraemic, and had higher values of alanine aminotransferase when compared with HCV-monoinfected children. No relevant difference was reported between monoinfection and co-infection with regard to clinical findings. Although the data on the outcome of hepatitis C in the context of co-infection were limited, they were highly suggestive of a more severe outcome in terms of fibrosis in co-infected children. No pediatric data were available on the role of antiretroviral therapy as a cofactor of liver injury in HCV/HIV co-infection. The efficacy of pegylated interferon-α and ribavirin in children with HCV/HIV co-infection was lower than in monoinfected children. CONCLUSIONS: The effect of HIV co-infection on HCV-related disease was clear with most studies indicating that HIV accelerates HCV progression and reduces the efficacy of the available anti-HCV therapies.

A kwashiorkor case due to the use of an exclusive rice milk diet to treat atopic dermatitis.

Although several cases of severe hypoalbuminemia resulting from rice milk have been described in the past, today the use of rice milk without nutritional counseling to treat eczema is still a continuing, poor practice. We describe a kwashiorkor case in an infant with severe eczema exclusively fed with rice milk. It is well documented that rice milk is not a sufficient protein source. Moreover, only a small portion of eczema is triggered by food allergy. In conclusion this case raises the importance of managing dietary changes facing food allergies with responsibility for specialized consensus among pediatricians, nutritionists, endocrinologists and allergists all of them specialist professionals.

Aortic Arch Interruption and Persistent Fifth Aortic Arch in Phace Syndrome: Prenatal Diagnosis and Postnatal Course.

PHACE is a rare congenital neurocutaneous syndrome where posterior fossa malformations, hemangiomas, cerebrovascular anomalies, aortic arch anomalies, cardiac defects, and eye abnormalities are variably associated. We describe the prenatal detection and the postnatal course of a child with PHACE syndrome with a unique type of aortic arch anomaly consisting of proximal interruption of the aortic arch and persistence of the fifth aortic arch. The fifth aortic arch represented in this case a vital systemic-to-systemic connection between the ascending aorta and the transverse portion of the aortic arch allowing adequate forward flow through the aortic arch without surgical treatment.

Interleukin 28B rs12979860 single-nucleotide polymorphism predicts spontaneous clearance of hepatitis C virus in children.

OBJECTIVE: Recent genome-wide association studies performed in adults correlated single-nucleotide polymorphisms (SNPs rs12979860 and rs8099917) located on chromosome 19, upstream of the interleukin 28B gene, with spontaneous clearance of hepatitis C virus and with response to treatment with paginated interferon and ribavirin. The aim of the present collaborative study was to evaluate the rs12979860 SNP in a large cohort of Italian children with perinatal acquisition of hepatitis C. METHODS: Children were prospectively enrolled in 2 Italian centers. The interleukin 28B rs12979860 SNP was studied according to the diagnosis of chronic infection or spontaneous clearance. RESULTS: One hundred thirty children (86.7%) with chronic infection and 23 (13.3%) with spontaneous clearance of the virus were enrolled. Overall, the interleukin 28B C/C and C/T-T/T genotypes were found in 57 (37.3%) and 96 (62.7%) children, respectively. The proportion of C/C genotype was higher among children who cleared infection (14/23; 60.9%) compared with children with chronic infection (43/130; 33.1%; P = 0.01; odds ratio 3.15; 90% confidence intervals 1.34-7.53). CONCLUSIONS: The present study showed that, as already demonstrated in adults, children with the rs12979860 C/C SNP of the interleukin 28B gene have a higher probability of spontaneous clearance of hepatitis C virus.

Genotype-phenotype relationships of truncating mutations, p.E297G and p.D482G in bile salt export pump deficiency.

Background & Aims: Bile salt export pump (BSEP) deficiency frequently necessitates liver transplantation in childhood. In contrast to two predicted protein truncating mutations (PPTMs), homozygous p.D482G or p.E297G mutations are associated with relatively mild phenotypes, responsive to surgical interruption of the enterohepatic circulation (siEHC). The phenotype of patients with a compound heterozygous genotype of one p.D482G or p.E297G mutation and one PPTM has remained unclear. We aimed to assess their genotype-phenotype relationship. Methods: From the NAPPED database, we selected patients with homozygous p.D482G or p.E297G mutations (BSEP1/1; n = 31), with one p.D482G or p.E297G, and one PPTM (BSEP1/3; n = 30), and with two PPTMs (BSEP3/3; n = 77). We compared clinical presentation, native liver survival (NLS), and the effect of siEHC on NLS. Results: The groups had a similar median age at presentation (0.7-1.3 years). Overall NLS at age 10 years was 21% in BSEP1/3 vs. 75% in BSEP1/1 and 23% in BSEP3/3 (p <0.001). Without siEHC, NLS in the BSEP1/3 group was similar to that in BSEP3/3, but considerably lower than in BSEP1/1 (at age 10 years: 38%, 30%, and 71%, respectively; p = 0.003). After siEHC, BSEP1/3 and BSEP3/3 were associated with similarly low NLS, while NLS was much higher in BSEP1/1 (10 years after siEHC, 27%, 14%, and 92%, respectively; p <0.001). Conclusions: Individuals with BSEP deficiency with one p.E297G or p.D482G mutation and one PPTM have a similarly severe disease course and low responsiveness to siEHC as those with two PPTMs. This identifies a considerable subgroup of patients who are unlikely to benefit from interruption of the enterohepatic circulation by either surgical or ileal bile acid transporter inhibitor treatment. Impact and implications: This manuscript defines the clinical features and prognosis of individuals with BSEP deficiency involving the combination of one relatively mild and one very severe BSEP deficiency mutation. Until now, it had always been assumed that the mild mutation would be enough to ensure a relatively good prognosis. However, our manuscript shows that the prognosis of these patients is just as poor as that of patients with two severe mutations. They do not respond to biliary diversion surgery and will likely not respond to the new IBAT (ileal bile acid transporter) inhibitors, which have recently been approved for use in BSEP deficiency.

Kawasaki syndrome and concurrent Coxsackie virus B3 infection.

We describe two previously healthy children who were hospitalized in the same period in different departments of our University with clinical signs of Kawasaki syndrome, which were treated with intravenous immunoglobulins and acetylsalicylic acid: in both cases, Coxsackie virus infection was concurrently demonstrated by enzyme-linked immunosorbent assay, and complement fixation test identified antibodies to serotype B3. In the acute phase, both patients presented hyperechogenic coronary arteries, but no cardiologic sequels in the mid term. The etiological relationship between Kawasaki syndrome and Coxsackie viruses is only hypothetical; however, the eventual identification of ad hoc environmental triggers is advisable in front of children with Kawasaki syndrome, with the aim of optimizing epidemiological surveillance and understanding the intimate biological events of this condition.

Diagnostic approach to neonatal and infantile cholestasis: A position paper by the SIGENP liver disease working group.

Neonatal and infantile cholestasis (NIC) can represent the onset of a surgically correctable disease and of a genetic or metabolic disorder worthy of medical treatment. Timely recognition of NIC and identification of the underlying etiology are paramount to improve outcomes. Upon invitation by the Italian National Institute of Health (ISS), an expert working grouped was formed to formulate evidence-based positions on current knowledge about the diagnosis of NIC. A systematic literature search was conducted to collect evidence about epidemiology, etiology, clinical aspects and accuracy of available diagnostic tests in NIC. Evidence was scored using the GRADE system. All recommendations were approved by a panel of experts upon agreement of at least 75% of the members. The final document was approved by all the panel components. This position document summarizes the collected statements and defines the best-evidence diagnostic approach to cholestasis in the first year of life.

Systematic review with meta-analysis: the efficacy and safety of direct-acting antivirals in children and adolescents with chronic hepatitis C virus infection.

BACKGROUND: The effect of direct-acting anti-virals (DAAs) in children and adolescents with chronic hepatitis C virus (HCV) infection is difficult to determine, since few, aged between 3 and 18 years, have been enrolled in clinical trials, and some data come from observational studies. AIM: To summarise the evidence on efficacy and safety of DAAs in children and adolescents with chronic HCV infection. METHODS: We performed a systematic review and meta-analysis of prospective studies on the efficacy and safety of DAAs in subjects <18 years of age. We considered the sustained virological response at post-treatment week 12 as efficacy outcome and adverse events as safety outcome. We considered intervention effect for each study arm by calculating the proportion of sustained virologic response at post-treatment week 12 in subjects receiving all doses of treatment and proportion of adverse events in subjects receiving at least one dose of treatment. Pooled proportions were calculated using the Freeman-Tukey double arcsine transformation. Random effects model was used for all analyses. RESULTS: Among 39 included studies (1796 subjects), the pooled proportion among those receiving all doses of treatment and reaching sustained virologic response at post-treatment week 12 was 100% (95% confidence interval: 100-100). Considering subjects receiving at least one dose of treatment, lowest estimates were reported among children with cirrhosis (83%). Headache and fatigue were the most common adverse events. Serious adverse events were uncommon. CONCLUSIONS: Children and adolescents with chronic HCV infection can be safely treated with DAAs with similar efficacy as reported in adults.

Hepatitis C Genotype 4 Virus Nonstructural 3 and Nonstructural 5A Resistance-associated Substitutions in a 16-year-old Adolescent Failing Ombitasvir/Paritaprevir/Ritonavir Plus Ribavirin.

Preexistence and appearance of resistance-associated substitutions limit the efficacy of direct-acting antivirals in treatment of hepatitis C. This is the first case report of an adolescent with chronic hepatitis C virus genotype 4 infection and cirrhosis who failed treatment with ombitasvir/paritaprevir/ritonavir and ribavirin. Resistance analysis showed baseline resistance-associated substitutions M28V and Y93C and emergent D168H.

Immunological Features of Neuroblastoma Amplified Sequence Deficiency: Report of the First Case Identified Through Newborn Screening for Primary Immunodeficiency and Review of the Literature.

This is the first case of NBAS disease detected by NBS for primary immunodeficiency. NBS with KRECs is revealing unknown potentialities detecting conditions that benefit from early recognition like NBAS deficiency. Immune phenotyping should be mandatory in patients with NBAS deficiency since they can exhibit severe immunodeficiency with hypogammaglobulinemia as the most frequent finding. Fever during infections is a known trigger of acute liver failure in this syndrome, so immune dysfunction, should never go unnoticed in NBAS deficiency in order to start adequate therapy and prophylaxis.

Significant impact of pneumococcal conjugate vaccination on pediatric parapneumonic effusion: Italy 2006-2018.

Etiology and serotyping of parapneumonic effusion (PPE) and the impact of vaccination was evaluated over a 12-year period, before and after the PCV13 introduction (2011) for Italian children From 0 to 16 years of age. Five hundred and two children were evaluated; 226 blood and 356 pleural fluid samples were obtained and tested using Realtime-PCR and culture. In the pre-PCV13 era S. pneumoniae was the most frequent pathogen identified (64/90; 71.1%) with a large predominance of serotypes 1 (42.4%), 3 (23.7%), 7F (5.1%) and 19A (11.9%). The impact of vaccination, calculated on children 0-8 years of age, demonstrated a significant reduction of PPE: with an incidence rate of 2.82 (95%CL 2.32-3.41) in the pre-PCV13 era and an age-standardized rate (ASR) of 0.66 (95% CL 0.37-1.99) in the post-PCV13 era, p < 0.0001. No increase in non-PCV13 serotypes was recorded. S. pneumoniae remained the most frequent pathogen identified in the post-PCV13 era in unvaccinated children with an unchanged serotype distribution: respectively 26/66 (39.4%), 25/66 (37.9%), 5/66 (7.6%), and 4/66 (6.1%) for 1, 3, 7F and 19A. On the other hand 7F and 19A disappeared in vaccinated children and serotype 1 and 3 decreased by 91.8% and 31.5%, respectively. Realtime PCR was significantly more sensitive than culture both in pleural fluid (79.7% vs 12.5%) and in blood (17.8% vs 7.4%). In conclusion, our findings indicate that routine immunization with PCV13 has significantly reduced the burden of childhood PPE in vaccinated children, without increasing PPE due to other bacteria and without serotype shift. Moreover, the impact of PCV13 may be underestimated due to the increase in pneumococcal surveillance in Italy. Data has also shown that Real-time PCR is an essential tool to better define the etiology of PPE and to monitor vaccination plans. Longer studies will be necessary to evaluate the role of herd protection in PPE prevention.