Fernando Ferrero

Penicillin resistant pneumococcus and risk of treatment failure in pneumonia

Objective: To determine whether the presence of in vitro penicillin-resistant Streptococcus pneumoniae increases the risk of clinical failure in children hospitalised with severe pneumonia and treated with penicillin/ampicillin. Design: Multicentre, prospective, observational study. Setting: 12 tertiary-care centres in three countries in Latin America. Patients: 240 children aged 3–59 months, hospitalised with severe pneumonia and known in vitro susceptibility of S pneumoniae. Intervention: Patients were treated with intravenous penicillin/ampicillin after collection of blood and, when possible, pleural fluid for culture. The minimal inhibitory concentration (MIC) test was used to determine penicillin susceptibility of the pneumococcal strains isolated. Children were continuously monitored until discharge. Main outcome measures: The primary outcome was treatment failure (using clinical criteria). Results: Overall treatment failure was 21%. After allowing for different potential confounders, there was no evidence of association between treatment failure and in vitro resistance of S pneumoniae to penicillin according to the Clinical Laboratory Standards Institute (CLSI)/National Committee for Clinical Laboratory Standards (NCCLS) interpretative standards (adjRR = 1.03; 95%CI: 0.49–1.90 for resistant S pneumoniae). Conclusions: Intravenous penicillin/ampicillin remains the drug of choice for treating penicillin-resistant pneumococcal pneumonia in areas where the MIC does not exceed 2 μg/ml.

Diagnosis and treatment of tuberculosis in children: an updated review of an old problem

OBJECTIVE Tuberculosis is still one of the most severe chronic diseases, especially in the worlds poorest regions. Developing countries still have to face serious problems related to this endemic disease, in spite of the control programs they have implemented. The present study aims at updating the diagnosis and treatment of tuberculosis in three South American countries: Brazil, Chile and Argentina. SOURCES Medline and Lilacs databases, official guidelines and consensuses of the three countries involved. SUMMARY OF THE FINDINGS Brazil, Chile and Argentina have guidelines based on the World Health Organization documents and on international consensuses. The standardization is similar between these countries, allowing the unification of language and favoring control measures. Within the Brazilian context, the new guidelines on the treatment of tuberculosis set out by the Ministry of Health are presented. CONCLUSIONS Since each country had to make adaptations in an attempt to solve the epidemiological differences between them, the treatments against tuberculosis still present some discrepancies, such as the use of three or four drugs in some cases.

Mortality due to Respiratory Syncytial Virus. Burden and Risk Factors.

Rationale: Respiratory syncytial virus (RSV) is the most frequent cause of hospitalization and an important cause of death in infants in the developing world. The relative contribution of social, biologic, and clinical risk factors to RSV mortality in low‐income regions is unclear. Objectives: To determine the burden and risk factors for mortality due to RSV in a low‐income population of 84,840 infants. Methods: This was a prospective, population‐based, cross‐sectional, multicenter study conducted between 2011 and 2013. Hospitalizations and deaths due to severe lower respiratory tract illness (LRTI) were recorded during the RSV season. All‐cause hospital deaths and community deaths were monitored. Risk factors for respiratory failure (RF) and mortality due to RSV were assessed using a hierarchical, logistic regression model. Measurements and Main Results: A total of 2,588 (65.5%) infants with severe LRTI were infected with RSV. A total of 157 infants (148 postneonatal) experienced RF or died with RSV. RSV LRTI accounted for 57% fatal LRTI tested for the virus. A diagnosis of sepsis (odds ratio [OR], 17.03; 95% confidence interval [CI], 13.14‐21.16 for RF) (OR, 119.39; 95% CI, 50.98‐273.34 for death) and pneumothorax (OR, 17.15; 95% CI, 13.07‐21.01 for RF) (OR, 65.49; 95% CI, 28.90‐139.17 for death) were the main determinants of poor outcomes. Conclusions: RSV was the most frequent cause of mortality in low‐income postneonatal infants. RF and death due to RSV LRTI, almost exclusively associated with prematurity and cardiopulmonary diseases in industrialized countries, primarily affect term infants in a developing world environment. Poor outcomes at hospitals are frequent and associated with the cooccurrence of bacterial sepsis and clinically significant pneumothoraxes.

Radiographic findings among children hospitalized with severe community‐acquired pneumonia

Community‐acquired pneumonia (CAP) is a leading cause of childhood death. There are few published reports of radiographic findings among children with severe CAP.

Depletion of Circulating Regulatory T Cells during Severe Respiratory Syncytial Virus Infection in Young Children

Fil: Raiden, Silvina Claudia. Gobierno de la Ciudad de Buenos Aires. Hospital General de Ninos Pedro Elizalde (ex Casa Cuna); Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clinicas General San Martin; Argentina

Validación de una regla de predicción clínica para diferenciar meningitis bacteriana de meningitis aséptica

INTRODUCTION Despite most meningitis are not bacterial, antibiotics are usually administered on admission because bacterial meningitis is difficult to be rule-out. Distinguishing bacterial from aseptic meningitis on admission could avoid inappropriate antibiotic use and hospitalization. We aimed to validate a clinical prediction rule to distinguish bacterial from aseptic meningitis in children, on arriving to the emergency room. METHODS This prospective study included patients aged < 19 years with meningitis. Cerebrospinal fluid (CSF) and peripheral blood neutrophil count were obtained from all patients. The BMS (Bacterial Meningitis Score) described by Nigrovic (Pediatrics 2002; 110: 712), was calculated: positive CSF Gram stain= 2 points, CSF absolute neutrophil count > or = 1000 cells/mm(3), CSF protein > or = 80 mg/dl, peripheral blood absolute neutrophil count > or = 10.000/mm(3), seizure = 1 point each. Sensitivity (S), specificity (E), positive and negative predictive values (PPV and NPV), positive and negative likelihood ratios (PLR and NLR) of the BMS to predict bacterial meningitis were calculated. RESULTS Seventy patients with meningitis were included (14 bacterial meningitis). When BMS was calculated, 25 patients showed a BMS= 0 points, 11 BMS= 1 point, and 34 BMS > or = 2 points. A BMS = 0 showed S: 100%, E: 44%, VPP: 31%, VPN: 100%, RVP: 1,81 RVN: 0. A BMS > or = 2 predicted bacterial meningitis with S: 100%, E: 64%, VPP: 41%, VPN: 100%, PLR: 2.8, NLR:0. CONCLUSIONS Using BMS was simple, and allowed identifying children with very low risk of bacterial meningitis. It could be a useful tool to assist clinical decision making.

Clinical Prediction Rules and Pediatric Infectious Diseases

Clinical prediction rules (CPR) are tools including appropriately weighted clinical aspects (history, physical examination and/or complementary tests) showing the odds for a specific diagnosis or prognosis. Their development includes a complex and strict process to achieve the scientific strength which supports use in clinical settings. Although CPR may be developed for almost any clinical situation, they are particularly useful in complex decision making, high-risk situations and for health cost reduction. Most CPR in pediatrics are devoted to infectious diseases, but only a few of them are used in daily practice. Reluctance in using them may be related to the most pediatricians expectation of 100% sensitivity, when only a few CPR have sensitivity >90%. It is important to take into account that even a less-than-perfect CPR may be more sensitive than the physicians clinical judgment alone.

Evaluación de la producción científica en la residencia de pediatría

INTRODUCTION Despite the impact that training in research could have in postgraduate programs, certain specific knowledge of the trainees may increase their scientific production. We described the scientific production of a pediatric residency, and evaluated its association with specific knowledges and activities. METHODS We developed a cross-sectional study, by self-administered survey to pediatric residents. The number of participations in research projects was registered, as well as certain specific knowledges and activities (informatics, English language, research methodology, university teaching positions). This association was assessed by logistic regression. RESULTS We interviewed 122 pediatric residents (first year: 22.1%, second year: 23.1%, third year: 19.1%, fourth year: 24.6%, chiefs residents: 9%, instructors: 3.3%). A total of 311 participations in research were registered (there could be more than 1 author in them). From them, 105 were presented at scientific meetings and 16 were published. Length of service and having a university teaching position were independent predictors for presentation (OR= 6.3 and 2.8, respectively) and publication (OR= 4.2 and 6.5, respectively). CONCLUSION Scientific production reached presentation at meetings in 33% of participations and publication, in 5%. Having a university teaching position was significantly associated with scientific production.

Validación de una herramienta de predicción clínica simple para la evaluación de la gravedad en niños con síndrome bronquial obstructivo

INTRODUCTION Acute lower respiratory infection in children usually causes Bronchial Obstructive Syndrome, which could include hipoxemia. Although pulse oximetry (SaO2) is the gold standard to evaluate hipoxemia, it is usually estimated from a clinical score not yet validated. We aimed to validate the respiratory distress score used in Argentina and to compare its performance with the one used in Chile. METHODS We included 200 children aged under 2 years, with Bronchial Obstructive Syndrome. On admission SaO2 and, Argentinean and Chilean scores components (respiratory rate, heart rate, wheezing, chest indrawing, cyanosis) were assessed. We evaluated the score components ability to predict hipoxemia (SaO2 < or = 95 and SaO2 < or = 91) by logistic regression. Correlation between Argentinean score and SaO2 was estimated. The best threshold of both scores to predict hipoxemia was calculated by ROC curve. Sensitivity, specificity, predictive values and likelihood ratios of both scores to predict hipoxemia were calculated. RESULTS Chest indrawing was an independent predictor of hipoxemia (SaO2 < or = 95 and SaO2 < or = 91) (OR: 3.1 IC95%:1.6-5.9 and OR: 13.8 IC95%:1.8-105.4, respectively). The Argentinean score showed acceptable correlation with SaO2 (Spearman: -0,492; p< 0,0001). On SaO2 < or = 91 the Argentinean score showed the best diagnostic performance (auc= 0.904). An Argentinean score > or = 5 was the best threshold to predict hipoxemia (Sensitivity= 100%, specificity= 54.3%). The Chilean score was also evaluated, showing a performance slightly worst than the Argentinean. CONCLUSION An Argentinean score > or = 5 points was sensitive enough to predict hipoxemia (SaO2 < or = 91). This score only allowed identifying children who does not benefit from supplementary oxygen.

Evaluación de dos métodos estandarizados de interpretación de radiografías de tórax en niños con neumonía

OBJECTIVE To evaluate the accuracy of World Health Organization (WHO) method of interpreting chest radiographs on identifying young children with bacterial pneumonia, and to compare its accuracy with other method. METHODS Chest radiographs from children aged under 5 years old hospitalized for pneumonia, with microbiological evidence of bacterial or viral infection, were evaluated by 3 observers blinded to other data (pediatrician [P], pulmonologist [N], radiologist [R]) according to WHO and Khamapirad scores. A WHO score=1 and a Khamapirad score >2 were selected as the thresholds suggesting bacterial pneumonia. The relationship between radiographic scores and etiology was evaluated using chi square. Sensitivity (Se), specificity (Sp), positive (PPV) and negative (NPV) predictive values for predicting bacterial pneumonia were calculated. Interobserver agreement (P vs. N vs. R) was calculated (kappa). RESULTS 108 chest radiographs were evaluated (87 viral, 21 bacterial). WHO score= 1 was associated with bacterial pneumonia (p <0.001; OR= 6.4; CI 95%= 1.629.7), achieving a Se= 85%, Sp= 51%, PPV= 30%, NPV= 93%. Khamapirad score >2, evaluated by P, was also associated with bacterial pneumonia (p <0.0008; OR= 6.31; CI 95%= 1.8-24.4), achieving a Se= 80%, Sp= 59%, PPV= 32% NPV= 92%. Interobserver agreement was slightly better using WHO score (P vs. N= 0.82, P vs. R= 0.69, N vs. R= 0.85) than Khamapirad score (P vs. N= 0.48, P vs. R= 0.69, N vs. R= 0.82). CONCLUSIONS Both methods showed similar accuracy in order to identify bacterial pneumonia. WHO score is simpler than Khamapirad score and showed a better interobserver agreement.