Comparison of Epidemiologic and Clinical COVID-19 Profiles in Children in Argentina, During Circulation of Original and Variant (Alpha, Gamma and Lambda) Strains.

BACKGROUND: Information on the impact of the different variants in children in Latin America is scarce. The objective of this study was to describe epidemiologic and clinical features of COVID-19 infection in children under 18 years of age in Argentina, comparing the periods before and after the circulation of new variants. METHODS: Observational, cross-sectional, multicentric, analytical study. All patients under 18 years of age with confirmed SARS-CoV-2 infection admitted at 22 healthcare centers were included. Two study periods were established: Period 1 (EW10-2020 to EW12-2021) for the Wuhan strain; Period 2 (EW13 to EW35 2021) for Alpha, Gamma, Delta and Lambda variants. FINDINGS: A total of 6330 confirmed cases were included. Period 1: 3575 (56.5%), period 2: 2755 (43.5%). During period 2, a lower number of asymptomatic cases was observed, while general, respiratory and neurologic signs and symptoms increased in all age groups. Oxygen therapy requirement was higher during the first period (36.7% vs 19.1%; P < 0.001). No significant differences were observed in the rates of severe or critical cases (6.3% vs 5,4%; P = 0.102), intensive care admission (2.1% vs 2%; P < 0.656) or case fatality (0.3% vs 0.5 %; P < 0.229). MIS-C cases occurred more frequently during the first period (1.9% vs 1.1%; P = 0.009). INTERPRETATION: The clinical spectrum of COVID-19 in Argentina has evolved. With the emergence of new variants, although the number of asymptomatic cases declined, numbers of severe and critical cases, as well as case fatality rates in children, remained unchanged.

[Recommendations for care, prevention of infections and chemoprophylaxis in inborn errors of immunity]. / Recomendaciones para el cuidado, prevención de infecciones y quimioprofilaxis en los errores innatos de la inmunidad.

Inborn errors of immunity, previously named primary immunodeficiency are a heterogeneous group of genetic defects of different components of the immune system. Patients present high susceptibility to an only or several microorganisms, developing recurrent infections; the severity is related to the specific genetic type of immunity defect. The main strategy on the management of these illness is the prevention of infections. These consensus guidelines made by the Pediatric Immunology Work Group of Sociedad Argentina de Pediatría, givese main approaches of infection prevention in order to provide a useful tool for all practitioners who are involved in the management of these patients, based on scientific evidence and broad consensus of a specialized panel expert..

Los errores innatos de la inmunidad (EII), antes llamados inmunodeficiencias primarias (IDP), son un grupo heterogéneo de trastornos genéticos con defectos en uno o más componentes del sistema inmune. Los pacientes afectados por EII presentan aumentada susceptibilidad a microorganismos únicos o múltiples que se manifestará con infecciones recurrentes de diferente tipo y gravedad dependiendo del tipo de la localización del defecto. La prevención de infecciones es uno de los pilares fundamentales en el abordaje integral de los pacientes con EII. En este trabajo se resumen las conclusiones consensuadas en el Grupo de Trabajo de Inmunología Pediátrica de la Sociedad Argentina de Pediatría, sobre la base de la revisión de la evidencia disponible, respecto a los principios esenciales para el cuidado, la prevención de infecciones y la quimioprofilaxis en los errores innatos de la inmunidad para la orientación del pediatra y especialista dedicados al seguimiento de estas enfermedades.

A multicenter study of confirmed COVID-19 cases: preliminary data on 2690 pediatric patients in Argentina during the first year of the pandemic. / Estudio multicéntrico de casos confirmados de COVID-19: datos preliminares de 2690 pacientes pediátricos en Argentina durante el primer año de la pandemia.

INTRODUCTION: The current evidence indicates that the severity of the coronavirus disease 2019 (COVID-19) is lower in the pediatric population but local data are still limited. Objective: To characterize the clinical and epidemiological aspects of COVID-19 infection in patients younger than 18 years in Argentina. POPULATION AND METHODS: Cross-sectional, observational, and analytical study of confirmed COVID-19 patients aged 0-18 years seen between March 2020 and March 2021 at 19 referral children's hospitals of Argentina. A multivariate analysis was done to identify predictors of severe cases. RESULTS: A total of 2690 COVID-19 cases were included: 77.7% lived in the Metropolitan Area of Buenos Aires; 50.1% were males; patients' median age was 5.6 years. Of them, 90% were seen during epidemiological weeks 20-47 of 2020; 60.4% had a history of contact with COVID-19 patients; and 96.6% in their family setting. Also, 51.4% had respiratory symptoms; 61.6%, general symptoms; 18.8%, gastrointestinal symptoms; 17.1%, neurological symptoms; 7.2%, other symptoms; and 21.5% were asymptomatic. In addition, 59.4% of patients were hospitalized and 7.4% had a severe or critical course. A total of 57 patients developed multisystem inflammatory syndrome. A history of asthma, bronchopulmonary dysplasia, congenital heart disease, moderate to severe malnutrition, obesity, chronic neurological disease and/or age younger than 6 months were independent predictors of severity. Living in a vulnerable neighborhood was a protective factor. CONCLUSIONS: More than half of cases referred a history of contact with COVID-19 patients in the family setting. Hospitalization was not based on clinical criteria of severity. Severity was associated with the presence of certain comorbidities.

Introducción. La evidencia actual indica que la gravedad de la enfermedad por el coronavirus 2019 (COVID-19, por su sigla en inglés) es menor en la población pediátrica, los datos locales aún son limitados. OBJETIVO: caracterizar los aspectos clínicos y epidemiológicos de la infección por COVID-19 en menores de 18 años en Argentina. Población y métodos. Estudio transversal, observacional y analítico de casos confirmados de COVID-19 entre 0 y 18 años asistidos entre marzo de 2020 y marzo de 2021 en 19 centros pediátricos de referencia de Argentina. Se realizó un análisis multivariado para identificar las variables predictoras de cuadros graves. RESULTADOS: Se incluyeron 2690 casos de COVID-19: 77,7 % residentes del área metropolitana de Buenos Aires, 50,1 % de sexo masculino, mediana de edad de 5,6 años. El 90 % ocurrió entre las semanas epidemiológicas 2047 del 2020; 60,4 % con antecedente de contacto con personas con COVID-19; y 96,6 % en el entorno familiar. El 51,4 % presentó síntomas respiratorios; 61,6 % síntomas generales; 18,8 % síntomas gastrointestinales; 17,1 % síntomas neurológicos; 7,2 % otros y 21,5 % fueron asintomáticos. El 59,4 % fue hospitalizado; 7,4 % fueron graves o críticos. Se registraron 57 casos de síndrome inflamatorio multisistémico. El antecedente de asma, displasia broncopulmonar, cardiopatía congénita, desnutrición moderada a grave, obesidad, enfermedad neurológica crónica y/o edad menor de 6 meses resultaron predictores independientes de gravedad. Residir en barrios vulnerables resultó protector. CONCLUSIONES: Más de la mitad de los casos refirieron antecedente de contacto con personas con COVID-19 en el entorno familiar. La hospitalización no respondió a criterios clínicos de gravedad. La gravedad se encuentra asociada a la existencia de ciertas comorbilidades.

Factors Associated With Hospitalization or Intensive Care Admission in Children With COVID-19 in Latin America.

Background: Limited data is available from low-middle and upper-middle income countries of the factors associated with hospitalization or admission to pediatric intensive care unit (PICU) for children with COVID-19. Objective: To describe the factors associated with hospitalization or PICU admission of children with COVID-19 in Latin America. Method: Multicenter, analytical, retrospective study of children reported from 10 different Latin American countries to the Latin-American Society of Pediatric Infectious Diseases (SLIPE-COVID) research network from June 1, 2020, and February 28, 2021. Outpatient or hospitalized children <18 years of age with COVID-19 confirmed by polymerase chain reaction or antigen detection from the nasopharynx were included. Children with multisystem inflammatory syndrome in children (MIS-C) were excluded. Associations were assessed using univariate and multivariable logistic regression models. Results: A total of 1063 children with COVID-19 were included; 500 (47%) hospitalized, with 419 (84%) to the pediatric wards and 81 (16%) to the ICU. In multivariable analyses, age <1 year (Odds Ratio [OR] 1.78; 95% CI 1.08-2.94), native race (OR 5.40; 95% CI 2.13-13.69) and having a co-morbid condition (OR 5.3; 95% CI 3.10-9.15), were associated with hospitalization. Children with metabolic or endocrine disorders (OR 4.22; 95% CI 1.76-10.11), immune deficiency (1.91; 95% CI 1.05-3.49), preterm birth (OR 2.52; 95% CI 1.41-4.49), anemia at presentation (OR 2.34; 95% CI 1.28-4.27), radiological peribronchial wall thickening (OR 2.59; 95% CI 1.15-5.84) and hypoxia, altered mental status, seizures, or shock were more likely to require PICU admission. The presence of pharyngitis (OR 0.34; 95% CI 0.25-0.48); myalgia (OR 0.47; 95% CI 0.28-0.79) or diarrhea (OR 0.38; 95% CI 0.21-0.67) were inversely associated with hospital admission. Conclusions: In this data analysis reported to the SLIPE research network in Latin America, infants, social inequalities, comorbidities, anemia, bronchial wall thickening and specific clinical findings on presentation were associated with higher rates of hospitalization or PICU admission. This evidence provides data for prioritization prevention and treatment strategies for children suffering from COVID-19.

Community-acquired methicillin-resistant Staphylococcus aureus pneumonia in a children's hospital. Our ten-year experience. / Neumonía por Staphylococcus aureus resistente a meticilina adquirido de la comunidad en un hospital pediátrico. Nuestra experiencia de 10 años.

INTRODUCTION: Community-acquired methicillinresistant Staphylococcus aureus (CA-MRSA) infections have increased in recent years. CAMRSA necrotizing pneumonia and empyema are now more common in children. OBJECTIVES: To determine the prevalence of CA-MRSA pneumonia and its clinical and epidemiological characteristics compared to Streptococcus pneumoniae (SP) pneumonia in the same population. MATERIAL AND METHODS: Descriptive, observational, cross-sectional study of patients hospitalized due to CA-MRSA pneumonia at Hospital de Niños Víctor J. Vilela (period: January 2008-December 2017). RESULTS: Out of 54 Staphylococcus aureus pneumonia cases, 46 (85 %) corresponded to CA-MRSA. The rate of CA-MRSA pneumonia ranged from 4.9/10 000 (2008) to 10/10 000 hospital discharges (2017). Sepsis/septic shock was observed in 41 %; empyema, in 96 %; pneumothorax, in 35 %; 90 % of cases required pleural drainage and 55 %, surgical debridement. Also, 65 % of patients were admitted to the intensive care unit (ICU); half of them required assisted mechanical ventilation. Two patients died. Strain resistance: 17 %, gentamicin; 13 %, erythromycin; and 11 %, clindamycin. Compared to SP pneumonia, CAMRSA pneumonia showed a higher risk for sepsis (95 % confidence interval; relative risk: 7.38; 3.32- 16.38) and admission to the ICU (RR: 4.29; 2.70- 6.83). No patient died due to SP pneumonia. CONCLUSIONS: The prevalence of CA-MRSA pneumonia doubled in the past decade. Compared to SP pneumonia, CA-MRSA pneumonia was more commonly accompanied by sepsis and septic shock, admission to the ICU, and ventilatory support requirement.

Introducción. Las infecciones por Staphylococcus aureus resistente a meticilina adquirido de la comunidad (SARM-AC) se han incrementado en los últimos años. Neumonías necrotizantes y empiemas por SARM-AC son cada vez más frecuentes en niños. Objetivos. Determinar la prevalencia de neumonías por SARM-AC y sus características clínico-epidemiológicas, en comparación con las neumonías por Streptococcus pneumoniae (SP) en la misma población. Material y métodos. Estudio descriptivo, observacional, transversal, de pacientes internados con neumonía por SARM-AC en el Hospital de Niños Víctor J. Vilela (período: 1/2008-12/2017). Resultados. De 54 neumonías por Staphylococcus aureus, 46 (el 85 %) fueron SARM-AC. El índice de neumonías por SARM-AC varió de 4,9/10 000 (2008) a 10/10 000 egresos (2017). Presentaron sepsis/shock séptico el 41 %; empiema, el 96 %; neumotórax, el 35 %; requirieron drenaje pleural el 90 % y toilette quirúrgica el 55 %. Ingresaron a Terapia Intensiva el 65 %; la mitad necesitó asistencia respiratoria mecánica. Hubo dos muertes. Resistencia de las cepas: el 17 % a gentamicina, el 13 % a eritromicina, el 11 % a clindamicina. En las neumonías por SARM-AC vs. las neumonías por SP, se observó mayor riesgo de sepsis (IC 95 %; RR 7,38; 3,32-16,38) e ingreso a Terapia Intensiva (RR 4,29; 2,70-6,83). No hubo muertes por SP. Conclusiones. La prevalencia de neumonías por SARM-AC se duplicó durante la última década. Comparadas con las neumonías por SP, las neumonías por SARM-AC se acompañaron, más frecuentemente, de cuadros de sepsis y shock séptico, ingreso a Terapia Intensiva y asistencia respiratoria.

[Consensus on treatment of multisystemic inflammatory syndrome associated with COVID-19]. / Consenso sobre el tratamiento del síndrome inflamatorio multisistémico asociado a COVID-19.

The pandemic caused by the SARS-CoV-2 virus declared by the WHO in March 11th 2020, affects a small number of pediatric patients, who mostly present mild respiratory compromise and favorable evolution. However began to be observed in previously healthy children, an increase in cases defined as "Multisystemic Inflammatory Syndrome" (MIS-C) or "Kawasaki-like" post-COVID 19 (KLC) that evolve to shock and require hospitalization in the Pediatric Intensive Care Unit. MIS-C and KL-C are characterized by fever; signs of inflammation, gastrointestinal symptoms, and cardiovascular dysfunction, associated with sever forms of presentation with higher incidence of hypotension and/or shock. In the laboratory, markers of inflammation, hypercoagulability and myocardial damage are observed. Firstline drug treatment consists of intravenous immunoglobulin plus oral acetylsalicylic acid. A multidisciplinary approach is recommended for an accurate diagnosis and an early and effective treatment, in order to reduce morbidity and mortality.

La pandemia ocasionada por el nuevo coronavirus (SARS-CoV-2), declarada por la Organización Mundial de la Salud OMS) en marzo de 2020, afecta a un reducido número de pacientes pediátricos, quienes presentan, en su mayoría, compromiso respiratorio leve y evolución favorable. Sin embargo, en niños previamente sanos, comenzó a observarse un aumento de casos definidos como síndrome inflamatorio multisistémico (SIM-C) o similar a Kawasaki (Kawasaki-like) asociado a la enfermedad por el nuevo coronavirus (COVID-19) (KL-C) que evolucionan al shock y requieren internación en la unidad de cuidados intensivos. Los cuadros de SIM-C y los KL-C se caracterizan por fiebre, signos de inflamación, síntomas gastrointestinales y disfunción cardiovascular; las formas graves de presentación tienen mayor incidencia de hipotensión y/o shock. En el laboratorio se observan marcadores de inflamación, hipercoagulabilidad y daño miocárdico. El tratamiento farmacológico de primera línea consiste en la administración de inmunoglobulina por vía intravenosa más ácido acetilsalicílico por vía oral. Se recomienda un abordaje multidisciplinario para un diagnóstico certero y un tratamiento temprano y eficaz para disminuir la morbimortalidad.

[Community onset of methicillin resistant Staphylococcus aureus infections in previously healthy or health care-associated children in Argentina]. / Infecciones por Staphylococcus aureus resistente a meticilina adquiridas en la comunidad en niños antes sanos y en niños relacionados al hospital en la Argentina.

INTRODUCTION: Community-acquired methicillin-resistant Staphylococcus aureus infections (CA-MRSA) are prevalent in several countries of the world. These infections seem to differ clinically from those occurring within the health care system (HCS-MRSA). OBJECTIVE: To compare clinical characteristics of infections by CA-MRSA and HCA-MRSA in the same community. MATERIAL AND METHODS: Prospective, multicentric and comparative study. Children with clinically and microbiologically documented CA-MRSA were included. RESULTS: Between 11/2006 and 11/2007, 840 infections caused by S. aureus were diagnosed. Of them 582 (68%) were community-acquired. Among these 356 (61%) were CA-MRSA. In this group, 75 (21%) were HCA-MRSA and 281 (79%) CA-MRSA. The median age was 36 months (range: 1-201). Chronic skin disease (13) and chronic disease of CNS (9) were the underlying disease predominant. Children with CA-MRSA had more frequency of previous antibiotic treatment (63 vs 34%) and previous medical consult (76 vs 52%), invasive procedures (31 vs 8%), surgery (15 vs 0.3%) and fever (94 vs 74%) (p = < 05). Children with CA-MRSA had subcutaneous abscesses (34 vs 15%) (p = < .05) more frequently. Bacteremia and sepsis rate was similar in both groups (21 vs 18%) and 17 vs 11%) respectively) (p = NS). Antibiotic resistance was more frequent in children with HCA-MRSA: Rifampin (7 vs 1%), trimethoprim-sulphametoxazole (7 vs 1%) and clindamycin (25 vs 9%) (p = < .05). Four children (5%) with HCA-MRSA infections died and 3 (1%) mCA-MRSA group (p = .05). CONCLUSION: Children with HCA-MRSA infections more frequent antibiotic resistance than CA-MRSA should be reconsider the empiric antibiotic treatment of community-acquired infections in children in our area.

Community-acquired methicillin-resistant Staphylococcus aureus infections: 10-years' experience in a children's hospital in the city of Rosario, Argentina. / Infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad: experiencia de 10 años en un hospital pediátrico de Rosario, Argentina.

INTRODUCTION: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are a common reason for consultation in pediatrics. Most of them present as skin and soft tissue infections; however, invasive infections have increased during the last decade. OBJECTIVES: The main objective was to describe the clinical-epidemiological characteristics of CA-MRSA infections. The secondary objective was to compare prevalence, clinical presentation and antibiotic susceptibility with a pre-study period (1/2004-12/2007). MATERIAL AND METHODS: This is a descriptive, prospective, cross-sectional study. Inclusion criteria: children who have been diagnosed with CA-MRSA infection and admitted to Hospital de Niños de Rosario between January 2008 and December 2014. Exclusion criteria: recent hospitalization, previous antibiotic treatment or surgery, comorbidities or immune compromise. RESULTS: Out of 728 cases of children with Staphylococcus aureus infections, 529 (73%) were due to CA-MRSA. The incidence rate of CA-MRSA infections varied from 12.2/10 000 hospital discharges in 2004 to 145/10 000 in 2014: 75% (391) were skin and soft tissue infections; 8% (43) were osteoarticular infections; 6% (30), pleuropulmonary infections; 5% (24), sepsis. There was an increase in the number of invasive infections in the second period, with no statistical significance (OR= 0.895; CI: 0.52-1.53). Gentamicin, clindamycin and erythromycin resistance remained stable throughout both periods. CONCLUSION: CA-MRSA infections were increasingly more frequent, mainly skin and soft tissue infections. An increase was observed in the number of invasive infections, with no statistical significance. Antibiotic resistance remained stable.

INTRODUCCIÓN: Las infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad (SAMR-ac) son motivo de consulta frecuente en pediatría. La mayoría se presentan como infecciones de piel y partes blandas; sin embargo, en la última década, se ha constatado un aumento de las infecciones invasivas. OBJETIVOS: El objetivo principal es describir las características clínico-epidemiológicas de las infecciones producidas por SAMR-ac. El objetivo secundario es comparar la prevalencia, presentación clínica y susceptibilidad antibiótica con un período previo de estudio (1/2004-12/2007). MATERIAL Y MÉTODOS: Estudio descriptivo, prospectivo, de tipo transversal. Criterios de inclusión: niños con diagnóstico de infección por SAMR-ac admitidos en el Hospital de Niños de Rosario, período de enero de 2008 a diciembre de 2014. Criterios de exclusión: internación reciente, antibiótico o cirugía previa, comorbilidades o inmunocompromiso. RESULTADOS: De 728 niños con infecciones por Staphylococcus aureus, 529 (73%) fueron por SAMR-ac. La tasa de incidencia de infecciones por SAMR-ac varió de 12,2/10 000 egresos hospitalarios de 2004 a 145/10 000 del 2014: 75% (391) fueron infecciones de piel y partes blandas; 8% (43), os teo articular es; 6% (30), pleuropulmonares; 5% (24), sepsis. Se observó un aumento en el número de infecciones invasivas en el 2o período sin significancia estadística (OR= 0,895; IC: 0,52-1,53). La resistencia a gentamicina, clindamicina y eritromicina se mantuvo estable en ambos períodos. CONCLUSIÓN: Las infecciones por SAMR-ac fueron cada vez más frecuentes, principalmente, las de piel y partes blandas. Se observó un aumento en el número de infecciones invasivas sin significancia estadística. La resistencia antibiótica se mantuvo estable.

PCV13 vaccination impact: A multicenter study of pneumonia in 10 pediatric hospitals in Argentina.

INTRODUCTION: In 2012, PCV13 was introduced into the National Immunization Program in Argentina, 2+1 schedule for children <2 years. Coverage rates for 1st and 3rd doses were 69% and 41.0% in 2012, 98% and 86% in 2013; 99% and 89% in 2014, respectively. The aims of this study were to evaluate impact of PCV13 on Consolidated Pneumonia (CP) and Pneumococcal Pneumonia (PP) burden, and to describe epidemiological-clinical pattern of PP during the three-year period following vaccine introduction. METHODS: Hospital-based study at 10 pediatric surveillance units in Argentina. CP and PP discharge rates per 10,000 hospital discharges were compared between the pre-vaccination period 2007-2011 (preVp), the year of intervention (2012) and the post-vaccination period 2013-2014 (postVp). RESULTS: Significant reduction in CP and PP discharge rates was observed in patients <5 years [% reduction (95%CI)]: 10.2% (6.3; 14.0) in 2012 and 24.8% (21.3; 28.2) in postVp for CP discharge rate; 59.5% (48.0; 68.5) in 2012 and 68.8% (58.3; 76.6) in postVp for PP discharge rate. Significant changes were also observed in children ≥5 years, mainly in PP discharge rate. A total of 297 PP cases were studied; 59.3% male; 31.3% <2 years; 42.9% had received PCV13 in 2012 and 84.5% in posVp. Case fatality rate was 3.4%. PCV13 serotypes decreased from 83.0% (39/47) in 2012 to 64.2% (52/81) in postVp, p = 0.039. CONCLUSIONS: After PCV13 introduction, significant reduction in CP and PP discharge rates was observed in hospitalized children <5 years. In patients ≥5 years, PP discharge rate also decreased significantly.

Community-acquired methicillin-resistant Staphylococcus aureus infections: hospitalization and case fatality risk in 10 pediatric facilities in Argentina. / Infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad: hospitalización y riesgo de letalidad en 10 centros pediátricos de Argentina.

INTRODUCTION: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are prevalent both in Argentina and worldwide, and they may have a severe clinical course. OBJECTIVES: To estimate the hospitalization rate and case fatality risk factors of CA-MRSA infection. METHODS: Cross-sectional, analytical study. All patients < 15 years old with community-acquired Staphylococcus aureus (CA-SA) infections admitted to 10 pediatric facilities between January 2012 and December 2014 were included. RESULTS: Out of 1141 patients with CA-SA, 904 (79.2%) had CA-MRSA. The rate of hospitalization of CA-MRSA cases (per 10 000 discharges) among patients < 5 years old was 27.6 in 2012, 35.2 in 2013, and 42.7 in 2014 (p = 0.0002). The 2-4-year-old group was the most affected one: 32.2, 49.4, and 54.4, respectively (p = 0.0057). The clinical presentations included skin and soft tissue infections: 66.2%, pneumonia: 11.5%, sepsis/bacteremia: 8.5%, osteomyelitis: 5.5%, arthritis: 5.2%, psoas abscess: 1.0%, pericarditis/endocarditis: 0.8%, meningitis: 0.6%, and other: 0.7%. In terms of antibiotic resistance, 11.1% had resistance to erythromycin; 8.4%, to gentamicin; and 0.6%, to trimethoprim-sulfamethoxazole. All strains were susceptible to vancomycin. The case fatality rate was 2.2% and associated risk factors were (odds ratio [95% confidence interval]) age > 8 years (2.78, 1.05-7.37), pneumonia (6.37, 2.3717.09), meningitis (19.53, 2.40-127.87), and sepsis/bacteremia (39.65, 11.94-145.55). CONCLUSIONS: The rate of CA-MRSA infection was high; the rate of hospitalization increased in the 2013-2014 period; the 2-4-year-old group was the most affected one. A higher case fatality risk was observed among patients > 8 years old and those with the clinical presentations of pneumonia, meningitis, and sepsis.

INTRODUCCIÓN: Las infecciones por Staphylococcus aureusmeticilino resistente adquirido en la comunidad (SAMR-C) son prevalentes en Argentina y el mundo; pueden tener evolución grave. OBJETIVOS: Estimar tasa de hospitalización y factores de riesgo de letalidad de la infección por SAMR-C. MÉTODOS: Estudio analítico transversal. Se incluyeron todos los pacientes < 15 años con infección por Staphylococcus aureusadquirido en la comunidad (SA-C) hospitalizados en 10 centros pediátricos, entre enero/2012-diciembre/2014. RESULTADOS: Del total de 1141 pacientes con infección por SA-C, 904 (79,2%) fueron SAMR-C. La tasa de hospitalización de casos de SAMR-C (por 10 000 egresos) en < 5 años fue 27,6 en 2012, 35,2 en 2013 y 42,7 en 2014 (p= 0,0002). El grupo de 2-4 años fue el más afectado: 32,2, 49,4 y 54,4, respectivamente (p= 0,0057). Las presentaciones clínicas fueron infección de piel y partes blandas (IPPB): 66,2%; neumonía:11,5%; sepsis/bacteriemia: 8,5%; osteomielitis: 5,5%; artritis: 5,2%; absceso de psoas: 1,0%; pericarditis/endocarditis: 0,8%; meningitis: 0,6%; otras: 0,7%. La resistencia antibiótica fue, para eritromicina, 11,1%; clindamicina, 11,0%; gentamicina, 8,4%; trimetoprima-sulfametoxazol: 0,6%. Todas las cepas fueron sensibles a vancomicina. La letalidad fue 2,2% y los factores de riesgo asociados fueron [OR (IC 95%)] edad > 8 años (2,78; 1,05-7,37), neumonía (6,37; 2,37-17,09), meningitis (19,53; 2,40-127,87) y sepsis/bacteriemia (39,65; 11,94-145,55). CONCLUSIONES: La tasa de infección por SAMR-C fue alta; la tasa de hospitalización aumentó en 2013-14; el grupo de 2-4 años fue el más afectado. Presentaron mayor riesgo de letalidad los > 8 años y las clínicas de neumonía, meningitis y sepsis.

Recomendaciones para el cuidado, prevención de infecciones y quimioprofilaxis en los errores innatos de la inmunidad / Recommendations for care, prevention of infections and chemoprophylaxis in inborn errors of immunity

Los errores innatos de la inmunidad (EII), antes llamados inmunodeficiencias primarias (IDP), son un grupo heterogéneo de trastornos genéticos con defectos en uno o más componentes del sistema inmune. Los pacientes afectados por EII presentan aumentada susceptibilidad a microorganismos únicos o múltiples que se manifestará con infecciones recurrentes de diferente tipo y gravedad dependiendo del tipo de la localización del defecto. La prevención de infecciones es uno de los pilares fundamentales en el abordaje integral de los pacientes con EII. En este trabajo se resumen las conclusiones consensuadas en el Grupo de Trabajo de Inmunología Pediátrica de la Sociedad Argentina de Pediatría, sobre la base de la revisión de la evidencia disponible, respecto a los principios esenciales para el cuidado, la prevención de infecciones y la quimioprofilaxis en los errores innatos de la inmunidad para la orientación del pediatra y especialista dedicados al seguimiento de estas enfermedades.

Inborn errors of immunity, previously named primary immunodeficiency are a heterogeneous group of genetic defects of different components of the immune system. Patients present high susceptibility to an only or several microorganisms, developing recurrent infections; the severity is related to the specific genetic type of immunity defect. The main strategy on the management of these illness is the prevention of infections. These consensus guidelines made by the Pediatric Immunology Work Group of Sociedad Argentina de Pediatría, givese main approaches of infection prevention in order to provide a useful tool for all practitioners who are involved in the management of these patients, based on scientific evidence and broad consensus of a specialized panel expert.

Meningococcal Disease in Children in Argentina A 3-year Active Sentinel Hospital Surveillance Study.

BACKGROUND: Meningococcal disease (MD) is a medical emergency and a serious public health problem. As new meningococcal vaccines become available, MD surveillance is crucial to provide baseline epidemiologic data before implementing preventive measures. We estimated MD incidence and epidemiology in Argentina using hospital-based surveillance. METHODS: Three-year prospective active surveillance in patients ≤15 years of age was conducted at 6 pediatric hospital sentinel units (March 2012 to February 2015). RESULTS: Of 184,360 hospitalized patients, 1444 (0.78%) had suspected meningitis or MD. Of these, 268 (19%) presented probable acute bacterial meningitis or MD, 168 (63%) were culture positive and 51 (30%) tested positive for Neisseria meningitidis. Of 100 culture-negative cases, 30 had positive meningococcal polymerase chain reaction. Thirteen patients presented other uncommon MD manifestations, resulting in a total of 94 MD cases and an annual incidence of 5.1/10 hospitalized patients [95% confidence interval (CI): 4-6]. Fifty-four (57%) patients were males, 48% were <1 year of age and the median age was 12.5 months (1 month to 15 years). Clinical presentations were the following: meningococcemia and meningitis (37%), meningitis (30%), meningococcemia (16%), arthritis (10%), bacteremia (5%) and pneumonia (2%). Twenty-eight percent had complications. Nine children died (case fatality rate: 10%), and 8 had sequelae. Serogroups were identified for 84 isolates. Serogroup W was associated with age <1 year (odds ratio: 3.18; 95% CI: 1.14-8.99); meningococcemia was associated with mortality (P = 0.0038). CONCLUSIONS: Highest rates of MD were observed among young infants. This study provides baseline data to estimate the impact of introducing meningococcal vaccines in Argentina.

Estudio multicéntrico de casos confirmados de COVID-19: datos preliminares de 2690 pacientes pediátricos en Argentina durante el primer año de la pandemia / A multicenter study of confirmed COVID-19 cases: preliminary data on 2690 pediatric patients in Argentina during the first year of the pandemic

Introducción. La evidencia actual indica que la gravedad de la enfermedad por el coronavirus 2019 (COVID-19, por su sigla en inglés) es menor en la población pediátrica, los datos locales aún son limitados. Objetivo: caracterizar los aspectos clínicos y epidemiológicos de la infección por COVID-19 en menores de 18 años en Argentina. Población y métodos. Estudio transversal, observacional y analítico de casos confirmados de COVID-19 entre 0 y 18 años asistidos entre marzo de 2020 y marzo de 2021 en 19 centros pediátricos de referencia de Argentina. Se realizó un análisis multivariado para identificar las variables predictoras de cuadros graves. Resultados. Se incluyeron 2690 casos de COVID-19: 77,7 % residentes del área metropolitana de Buenos Aires, 50,1 % de sexo masculino, mediana de edad de 5,6 años. El 90 % ocurrió entre las semanas epidemiológicas 20-47 del 2020; 60,4 % con antecedente de contacto con personas con COVID-19; y 96,6 % en el entorno familiar. El 51,4 % presentó síntomas respiratorios; 61,6 % síntomas generales; 18,8 % síntomas gastrointestinales; 17,1 % síntomas neurológicos; 7,2 % otros y 21,5 % fueron asintomáticos. El 59,4 % fue hospitalizado; 7,4 fueron graves o críticos. Se registraron 57 casos de síndrome inflamatorio multisistémico. El antecedente de asma, displasia broncopulmonar, cardiopatía congénita, desnutrición moderada a grave, obesidad, enfermedad neurológica crónica y/o edad menor de 6 meses resultaron predictores independientes de gravedad. Residir en barrios vulnerables resultó protector. Conclusiones. Más de la mitad de los casos refirieron antecedente de contacto con personas con COVID-19 en el entorno familiar. La hospitalización no respondió a criterios clínicos de gravedad. La gravedad se encuentra asociada a la existencia de ciertas comorbilidades.

Introduction. The current evidence indicates that the severity of the coronavirus disease 2019 (COVID-19) is lower in the pediatric population but local data are still limited. Objective: To characterize the clinical and epidemiological aspects of COVID-19 infection in patients younger than 18 years in Argentina. Population and methods. Cross-sectional, observational, and analytical study of confirmed COVID-19 patients aged 0-18 years seen between March 2020 and March 2021 at 19 referral children's hospitals of Argentina. A multivariate analysis was done to identify predictors of severe cases. Results. A total of 2690 COVID-19 cases were included: 77.7% lived in the Metropolitan Area of Buenos Aires; 50.1% were males; patients' median age was 5.6 years. Of them, 90% were seen during epidemiological weeks 20-47 of 2020; 60.4% had a history of contact with COVID-19 patients; and 96.6% in their family setting. Also, 51.4% had respiratory symptoms; 61.6%, general symptoms; 18.8%, gastrointestinal symptoms; 17.1%, neurological symptoms; 7.2%, other symptoms; and 21.5% were asymptomatic. In addition, 59.4% of patients were hospitalized and 7.4% had a severe or critical course. A total of 57 patients developed multisystem inflammatory syndrome. A history of asthma, bronchopulmonary dysplasia, congenital heart disease, moderate to severe malnutrition, obesity, chronic neurological disease and/or age younger than 6 months were independent predictors of severity.Livinginavulnerableneighborhoodwas a protective factor. Conclusions. More than half of cases referred a history of contact with COVID-19 patients in the family setting. Hospitalization was not based on clinical criteria of severity. Severity was associated with the presence of certain comorbidities

Neumonía por Staphylococcus aureus resistente a meticilina adquirido de la comunidad en un hospital pediátrico. Nuestra experiencia de 10 años / Community-acquired methicillin-resistant Staphylococcusaureus pneumonia in a children's hospital. Our ten-year experience

Introducción. Las infecciones por Staphylococcus aureus resistente a meticilina adquirido de la comunidad (SARM-AC) se han incrementado en los últimos años. Neumonías necrotizantes y empiemas por SARM-AC son cada vez más frecuentes en niños.Objetivos. Determinar la prevalencia de neumonías por SARM-AC y sus características clínico-epidemiológicas, en comparación con las neumonías por Streptococcus pneumoniae (SP) en la misma población.Material y métodos. Estudio descriptivo, observacional, transversal, de pacientes internados con neumonía por SARM-AC en el Hospital de Niños Víctor J. Vilela (período: 1/2008-12/2017).Resultados. De 54 neumonías por Staphylococcus aureus, 46 (el 85 %) fueron SARM-AC. El índice de neumonías por SARM-AC varió de 4,9/10 000 (2008) a 10/10 000 egresos (2017). Presentaron sepsis/shock séptico el 41 %; empiema, el 96 %; neumotórax, el 35 %; requirieron drenaje pleural el 90 % y toilette quirúrgica el 55 %. Ingresaron a Terapia Intensiva el 65 %; la mitad necesitó asistencia respiratoria mecánica. Hubo dos muertes. Resistencia de las cepas: el 17 % a gentamicina, el 13 % a eritromicina, el 11 % a clindamicina. En las neumonías por SARM-AC vs. las neumonías por SP, se observó mayor riesgo de sepsis (IC 95 %; RR 7,38; 3,32-16,38) e ingreso a Terapia Intensiva (RR 4,29; 2,70-6,83). No hubo muertes por SP.Conclusiones. La prevalencia de neumonías por SARM-AC se duplicó durante la última década. Comparadas con las neumonías por SP, las neumonías por SARM-AC se acompañaron, más frecuentemente, de cuadros de sepsis y shockséptico, ingreso a Terapia Intensiva y asistencia respiratoria.

Introduction. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have increased in recent years. CA-MRSA necrotizing pneumonia and empyema are now more common in children.Objectives. To determine the prevalence of CA-MRSA pneumonia and its clinical and epidemiological characteristics compared to Streptococcus pneumoniae (SP) pneumonia in the same population.Material and methods. Descriptive, observational, cross-sectional study of patients hospitalized due to CA-MRSA pneumonia at Hospital de Niños Víctor J. Vilela (period: January 2008-December 2017).Results. Out of 54 Staphylococcus aureus pneumonia cases, 46 (85 %) corresponded to CA-MRSA. The rate of CA-MRSA pneumonia ranged from 4.9/10 000 (2008) to 10/10 000 hospital discharges (2017). Sepsis/septic shock was observed in 41 %; empyema, in 96 %; pneumothorax, in 35 %; 90 % of cases required pleural drainage and 55 %, surgical debridement. Also, 65 % of patients were admitted to the intensive care unit (ICU); half of them required assisted mechanical ventilation. Two patients died. Strain resistance: 17 %, gentamicin; 13 %, erythromycin; and 11 %, clindamycin. Compared to SP pneumonia, CA-MRSA pneumonia showed a higher risk for sepsis (95 % confidence interval; relative risk: 7.38; 3.32-16.38) and admission to the ICU (RR: 4.29; 2.70-6.83). No patient died due to SP pneumonia.Conclusions. The prevalence of CA-MRSA pneumonia doubled in the past decade. Compared to SP pneumonia, CA-MRSA pneumonia was more commonly accompanied by sepsis and septic shock, admission to the ICU, and ventilatory support requirement

Consenso sobre el tratamiento del síndrome inflamatorio multisistémico asociado a COVID-19 / Consensus on treatment of multisystemic inflammatory syndrome associated with COVID-19

La pandemia ocasionada por el nuevo coronavirus (SARS-CoV-2), declarada por la Organización Mundial de la Salud OMS) en marzo de 2020, afecta a un reducido número de pacientes pediátricos, quienes presentan, en su mayoría, compromiso respiratorio leve y evolución favorable. Sin embargo, en niños previamente sanos, comenzó a observarse un aumento de casos definidos como síndrome inflamatorio multisistémico (SIM-C) o similar a Kawasaki (Kawasaki-like) asociado a la enfermedad por el nuevo coronavirus (COVID-19) (KL-C) que evolucionan al shock y requieren internación en la unidad de cuidados intensivos.Los cuadros de SIM-C y los KL-C se caracterizan por fiebre, signos de inflamación, síntomas gastrointestinales y disfunción cardiovascular; las formas graves de presentación tienen mayor incidencia de hipotensión y/o shock. En el laboratorio se observan marcadores de inflamación, hipercoagulabilidad y daño miocárdico. El tratamiento farmacológico de primera línea consiste en la administración de inmunoglobulina por vía intravenosa más ácido acetilsalicílico por vía oral.Se recomienda un abordaje multidisciplinario para un diagnóstico certero y un tratamiento temprano y eficaz para disminuir la morbimortalidad.

The pandemic caused by the SARS-CoV-2 virus declared by the WHO in March 11th 2020, affects a small number of pediatric patients, who mostly present mild respiratory compromise and favorable evolution.However began to be observed in previously healthy children, an increase in cases defined as "Multisystemic Inflammatory Syndrome" (MIS-C) or "Kawasaki-like" post-COVID 19 (KL-C) that evolve to shock and require hospitalization in the Pediatric Intensive Care Unit.MIS-C and KL-C are characterized by fever; signs of inflammation, gastrointestinal symptoms, and cardiovascular dysfunction, associated with sever forms of presentation with higher incidence of hypotension and/or shock. In the laboratory, markers of inflammation, hypercoagulability and myocardial damage are observed. First-line drug treatment consists of intravenous immunoglobulin plus oral acetylsalicylic acid.A multidisciplinary approach is recommended for an accurate diagnosis and an early and effective treatment, in order to reduce morbidity and mortality.

Risk factors for mortality caused by nontyphoidal Salmonella sp. in children.

OBJECTIVE: To identify the risk factors for mortality in extraintestinal nontyphoidal Salmonella (NTS) infections in infants and children. METHODS: We performed a retrospective analysis of 107 patients with at least one nonfecal culture for NTS seen from January 1988 to December 1995. RESULTS: The median age was 12 (range 1-216) months. Malnutrition was found in 55 patients (51%), and 22 (20%) displayed severe features (weight loss >40%). Seventy-two patients (67%) had previously been hospitalized, and 59 (55%) had received antibiotics during the month before admission. Fever (85%) and diarrhea (56%) were the most frequent clinical manifestations. Nineteen children (18%) had leukopenia. Forty-nine patients (46%) had only bacteremia, 33 (31%) bacteremia with focal infections, and 25 (23%) focal infections with negative blood cultures. Forty-seven strains (44%) were multiresistant, and 40 of them were nosocomially acquired. Eight patients (7%) had received inappropriate antibiotic treatment, and two of them died. Thirteen (12%) children died. Age, underlying disease, previous admission, previous antibiotic therapy, type of infection, susceptibility of the strains and inappropriate antibiotic treatment were not statistically significant risk factors for mortality. A logistic regression analysis selected the following variables as independently influencing outcome: malnutrition (P<0.01), leukopenia (P<0.002) and presence of diarrhea (P<0.02). CONCLUSIONS: Children with extraintestinal infections by NTS with leukopenia, malnutrition and presence of diarrhea have a higher risk of death.

Infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad: experiencia de 10 años en un hospital pediátrico de Rosario, Argentina / Community-acquired methicillin-resistant Staphylococcus aureus infections: 10-years' experience in a children's hospital in the city of Rosario, Argentina

Introducción: Las infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad (SAMR-ac) son motivo de consulta frecuente en pediatría. La mayoría se presentan como infecciones de piel y partes blandas; sin embargo, en la última década, se ha constatado un aumento de las infecciones invasivas. Objetivos: El objetivo principal es describir las características clínico-epidemiológicas de las infecciones producidas por SAMR-ac. El objetivo secundario es comparar la prevalencia, presentación clínica y susceptibilidad antibiótica con un período previo de estudio (1/2004-12/2007). Material y métodos: Estudio descriptivo, prospectivo, de tipo transversal. Criterios de inclusión: niños con diagnóstico de infección por SAMR-ac admitidos en el Hospital de Niños de Rosario, período de enero de 2008 a diciembre de 2014. Criterios de exclusión: internación reciente, antibiótico o cirugía previa, comorbilidades o inmunocompromiso. Resultados: De 728 niños con infecciones por Staphylococcus aureus, 529 (73%) fueron por SAMR-ac. La tasa de incidencia de infecciones por SAMR-ac varió de 12,2/10 000 egresos hospitalarios de 2004 a 145/10 000 del 2014: 75% (391) fueron infecciones de piel y partes blandas; 8% (43), os teo articular es; 6% (30), pleuropulmonares; 5% (24), sepsis. Se observó un aumento en el número de infecciones invasivas en el 2º período sin significancia estadística (OR= 0,895; IC: 0,52-1,53). La resistencia a gentamicina, clindamicina y eritromicina se mantuvo estable en ambos períodos. Conclusión: Las infecciones por SAMR-ac fueron cada vez más frecuentes, principalmente, las de piel y partes blandas. Se observó un aumento en el número de infecciones invasivas sin significancia estadística. La resistencia antibiótica se mantuvo estable.

Introduction: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are a common reason for consultation in pediatrics. Most of them present as skin and soft tissue infections; however, invasive infections have increased during the last decade. Objectives: The main objective was to describe the clinical-epidemiological characteristics of CA-MRSA infections. The secondary objective was to compare prevalence, clinical presentation and antibiotic susceptibility with a pre-study period (1/2004-12/2007). Material and methods: This is a descriptive, prospective, cross-sectional study. Inclusion criteria: children who have been diagnosed with CA-MRSA infection and admitted to Hospital de Niños de Rosario between January 2008 and December 2014. Exclusion criteria: recent hospitalization, previous antibiotic treatment or surgery, comorbidities or immune compromise. Results: Out of 728 cases of children with Staphylococcus aureus infections, 529 (73%) were due to CA-MRSA. The incidence rate of CA-MRSA infections varied from 12.2/10 000 hospital discharges in 2004 to 145/10 000 in 2014: 75% (391) were skin and soft tissue infections; 8% (43) were osteoarticular infections; 6% (30), pleuropulmonary infections; 5% (24), sepsis. There was an increase in the number of invasive infections in the second period, with no statistical significance (OR= 0.895; CI: 0.52-1.53). Gentamicin, clindamycin and erythromycin resistance remained stable throughout both periods. Conclusion: CA-MRSA infections were increasingly more frequent, mainly skin and soft tissue infections. An increase was observed in the number of invasive infections, with no statistical significance. Antibiotic resistance remained stable.

Infecciones por Staphylococcus aureus meticilino resistente adquirido en la comunidad: hospitalización y riesgo de letalidad en 10 centros pediátricos de Argentina / Community-acquired methicillin-resistant Staphylococcus aureus infections: hospitalization and case fatality risk in 10 pediatric facilities in Argentina

Introducción. Las infecciones por Staphylococcus aureusmeticilino resistente adquirido en la comunidad (SAMR-C) son prevalentes en Argentina y el mundo; pueden tener evolución grave. Objetivos: Estimar tasa de hospitalización y factores de riesgo de letalidad de la infección por SAMR-C. Métodos. Estudio analítico transversal. Se incluyeron todos los pacientes < 15 años con infección por Staphylococcus aureusadquirido en la comunidad (SA-C) hospitalizados en 10 centros pediátricos, entre enero/2012-diciembre/2014. Resultados. Del total de 1141 pacientes con infección por SA-C, 904 (79,2%) fueron SAMR-C. La tasa de hospitalización de casos de SAMR-C (por 10 000 egresos) en < 5 años fue 27,6 en 2012, 35,2 en 2013 y 42,7 en 2014 (p= 0,0002). El grupo de 2-4 años fue el más afectado: 32,2, 49,4 y 54,4, respectivamente (p= 0,0057). Las presentaciones clínicas fueron infección de piel y partes blandas (IPPB): 66,2%; neumonía:11,5%; sepsis/bacteriemia: 8,5%; osteomielitis: 5,5%; artritis: 5,2%; absceso de psoas: 1,0%; pericarditis/endocarditis: 0,8%; meningitis: 0,6%; otras: 0,7%. La resistencia antibiótica fue, para eritromicina, 11,1%; clindamicina, 11,0%; gentamicina, 8,4%; trimetoprima-sulfametoxazol: 0,6%. Todas las cepas fueron sensibles a vancomicina. La letalidad fue 2,2% y los factores de riesgo asociados fueron --#91;OR (IC 95%)--#93; edad > 8 años (2,78; 1,05-7,37), neumonía (6,37; 2,37-17,09), meningitis (19,53; 2,40-127,87) y sepsis/bacteriemia (39,65; 11,94-145,55). Conclusiones. La tasa de infección por SAMR-C fue alta; la tasa de hospitalización aumentó en 2013-14; el grupo de 2-4 años fue el más afectado. Presentaron mayor riesgo de letalidad los > 8 años y las clínicas de neumonía, meningitis y sepsis.

Introduction. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are prevalent both in Argentina and worldwide, and they may have a severe clinical course. Objectives: To estimate the hospitalization rate and case fatality risk factors of CA-MRSA infection. Methods. Cross-sectional, analytical study. All patients < 15 years old with community-acquired Staphylococcus aureus (CA-SA) infections admitted to 10 pediatric facilities between January 2012 and December 2014 were included. Results. Out of 1141 patients with CA-SA, 904 (79.2%) had CA-MRSA. The rate of hospitalization of CA-MRSA cases (per 10 000 discharges) among patients < 5 years old was 27.6 in 2012, 35.2 in 2013, and 42.7 in 2014 (p = 0.0002). The 2-4-year-old group was the most affected one: 32.2, 49.4, and 54.4, respectively (p = 0.0057). The clinical presentations included skin and soft tissue infections: 66.2%, pneumonia: 11.5%, sepsis/bacteremia: 8.5%, osteomyelitis: 5.5%, arthritis: 5.2%, psoas abscess: 1.0%, pericarditis/endocarditis: 0.8%, meningitis: 0.6%, and other: 0.7%. In terms of antibiotic resistance, 11.1% had resistance to erythromycin; 8.4%, to gentamicin; and 0.6%, to trimethoprim-sulfamethoxazole. All strains were susceptible to vancomycin. The case fatality rate was 2.2% and associated risk factors were (odds ratio --#91;95% confidence interval--#93;) age > 8 years (2.78, 1.05-7.37), pneumonia (6.37, 2.3717.09), meningitis (19.53, 2.40-127.87), and sepsis/bacteremia (39.65, 11.94-145.55). Conclusions. The rate of CA-MRSA infection was high; the rate of hospitalization increased in the 2013-2014 period; the 2-4-year-old group was the most affected one. A higher case fatality risk was observed among patients > 8 years old and those with the clinical presentations of pneumonia, meningitis, and sepsis.

[Study of respiratory influenza A H1N1 Virus (pH1N1) in hospitalized children in the pandemic year. Experience in 34 centers in Argentina]. / Estudio de las enfermedades respiratorias por virus Influenza A H1N1 (pH1N1) en niños internados durante el año de la pandemia. Experiencia de 34 centros en la Argentina.

INTRODUCTION: In Argentina, pandemic influenza pH1N1 caused nearly 10,000 confirmed cases with high impact in pediatrics. OBJECTIVES: To describe clinical and epidemiological characteristics and analyse the risk factor of lethality in children hospitalized with infection pH1N1 confirmed by PCR. POPULATION AND METHODS: We identifed all suspected cases (according to Ministry of health) in 34 centers and we included all the confirmed cases of 0-18 years from 1/4/09 to 31/8/09 in a retrospective cohort study. The viral diagnosis was confirmed by RT-PCR method. Data are expressed in percentages, average, median, standard deviation, and range (IQR) as appropriate; and as a measure of association, relative risk (RR), with 95% confidence interval (95%CI). Multiple logistic regression was conducted to determine the independent risk predictors. RESULTS: Total number of suspected cases were: 2367; PCR was performed to 47.8% (n: 1131) being positive for pH1N1 65.5% (n: 741/1131); 57.2% males; 61.5% <24 months, median age: 14 months (IQR 6-46 months); 45.1% with underlying disease; more frequent clinical pictures were: pneumonia (39,7%) and bronchiolitis 25.8%; Case-fatality rate: 5.9% (44/741). Mortality risk factors were [RR (95%CI)]: neurological disease [5.00 (2.84-8.81)], genetic disease [3.67 (1.58-8.52)], malnutrition [3,07 (1.46-6.48)] and prematurity [2.28 (1.14-4.56)]. Independent mortality predictor: neurological disease [3.84 (1.81-8.14)]. No significant association between age, chronic respiratory disease, immunosuppression and viral co-infection with lethality was observed. CONCLUSIONS: Almost half of children with pH1N1 infection had underlying disease; the neurological condition was a separate CFR predictor.