Jesús Feris-Iglesias

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.

Impact of Haemophilus influenzae type b conjugate vaccine on bacterial meningitis in the Dominican Republic

OBJECTIVES Widespread use of Haemophilus influenzae type b (Hib) vaccines has dramatically reduced the burden of Hib disease throughout the Americas. Few studies have evaluated the impact of Hib vaccination on non-culture-confirmed disease. This study analyzed trends in probable bacterial meningitis before and after the introduction of Hib vaccine in the Dominican Republic and estimated vaccine effectiveness against Hib meningitis. METHODS Meningitis cases among children < 5 years of age were identified from admission records of the main pediatric hospital in Santo Domingo during 1998-2004. Laboratory criteria were used to classify meningitis cases with probable bacterial etiology; confirmed cases had positive bacterial culture or antigen detection in cerebrospinal fluid. Cumulative incidence rates of confirmed and probable bacterial meningitis were calculated for children living in the National District. Confirmed cases of Hib meningitis were enrolled in a case-control study with age- and neighborhood-matched control children to calculate vaccine effectiveness. RESULTS Before vaccine introduction, annual rates of meningitis with probable bacterial etiology were 49 cases per 100 000 children < 5 years old; Hib accounted for 60% of confirmed bacterial cases. During 2002-2004, after vaccine introduction, annual rates of probable bacterial meningitis were 65% lower at 16 cases per 100 000, and Hib accounted for 26% of confirmed cases. Rates of Hib meningitis and probable bacterial meningitis with no determined etiology declined by 13 and 17 cases per 100 000, respectively. CONCLUSIONS Introduction of Hib vaccine substantially reduced the incidence of confirmed and probable bacterial meningitis in the Dominican Republic. The estimated impact of Hib vaccination was twice as great when non-culture-confirmed disease was included.

Disease Severity and Mortality Caused by Dengue in a Dominican Pediatric Population

Millions are infected with dengue yearly. We evaluated the epidemiological and clinical characteristics of pediatric patients infected with dengue in the Dominican Republic. The applicability of World Health Organization (WHO) warning signs for predicting severe dengue and mortality was also studied. This study was a cross-sectional retrospective review of patients with a clinical diagnosis of dengue. Univariate and multivariate analyses were performed to evaluate characteristics associated with severity and mortality. The study included 796 subjects: 288 subjects were classified as dengue, 290 subjects had alarm signs, and 207 subjects were classified as severe dengue. Common findings included thrombocytopenia (96%), abdominal pain (71%), and vomiting (59%). The most important factors associated with severe dengue were rash (P < 0.01), severe thrombocytopenia (P < 0.01), and anemia (P < 0.01). These signs and symptoms were also associated with mortality. This study validates the current WHO warning signs of severity. Rash and severe thrombocytopenia may be early warning signs and need additional study.

Empyema and bacteremic pneumococcal pneumonia in children under five years of age.

We compared bacteremic pneumococcal pneumonia (BPP) and pneumococcal empyema (PE), in terms of clinical, radiological, and laboratory findings, in under-fives. A cross-sectional nested cohort study, involving under-fives (102 with PE and 128 with BPP), was conducted at 12 centers in Argentina, Brazil, and the Dominican Republic. Among those with PE, mean age was higher; disease duration was longer; and tachypnea, dyspnea, and high leukocyte counts were more common. Among those with BPP, fever and lethargy were more common. It seems that children with PE can be distinguished from those with BPP on the basis of clinical and laboratory findings. Because both conditions are associated with high rates of morbidity and mortality, prompt diagnosis is crucial.

Aetiology of paediatric pneumonia with effusion in the Dominican Republic and the potential impact of pneumococcal conjugate vaccines

Pleural effusion is a serious complication of pneumonia, and Streptococcus pneumoniae is a leading cause. We describe the aetiology of pneumonia with effusion among children in the Dominican Republic before the introduction of the 13-valent pneumococcal conjugate vaccine (PCV) in 2013 and the performance characteristics of a rapid immunochromatographic test (ICT) for detecting S. pneumoniae in pleural fluid. From July 2009 to June 2011, we enrolled children <15 years old admitted with pneumonia and pleural effusion to Robert Reid Cabral Children’s Hospital, Dominican Republic. Pleural fluid was tested by culture, polymerase chain reaction (PCR) for bacterial (S. pyogenes, S. pneumoniae) and viral (respiratory syncytial virus and human rhinovirus) pathogens, and by ICT for S. pneumoniae. We calculated the performance of ICT and culture compared with PCR. Among 121 cases, the median age was 31 months (range 1 week to 14 years). Pleural fluid culture (n = 121) and PCR testing (n = 112) identified an aetiology in 85 (70.2%) cases, including 62 S. pneumoniae (51.2%) and 19 Staphylococcus aureus (15.7%). The viruses tested were not detected. The most prevalent pneumococcal serotypes were 14 (n = 20), 1 (n = 13), and 3 (n = 12). Serotype coverage of the 10- and 13-valent PCVs would be 70.5% and 95.1%, respectively. The sensitivity of point-of-care ICT was 100% (95% confidence interval [CI] 94.1%–100%), while specificity was 86.3% (95% CI 73.7%–94.3%). S. pneumoniae caused more than half of paediatric pneumonia with effusion cases; introduction of PCV in the Dominican Republic could reduce the burden by 36–49%. ICT is a practical, valid diagnostic tool for clinical care and surveillance in settings with limited laboratory capacity.

Prescripción de antimicrobianos antes y después de una intervención educativa en un país donde el proceso de re-certificación no es obligatorio

Background: The trend in increased antibiotic prescription practices has been associated with higher health care costs and antibiotic resistance. This study examined the adequate or inappropriate antibiotic prescribing practices of health professionals, who work in public and private health centers in the Dominican Republic (DR), before and after their participation in an educational intervention. Methods: Using self-administered questionnaires developed by the Alliance for the Prudential Use of Antibiotics (APUA), this quasi-experimental study evaluated the responses of physicians before (n=525) and after (n=364) their participation in an educational intervention, from August 2006 to February 2007 and March to August 2008, respectively. Statistical analyses included simple proportions, odds ratio and 95% confidence intervals (IC95%). Alpha was set at 0.05. Results: Post-intervention responses improved understanding significantly regarding specific situations for the prescription of cephalosporins, penicillins, macrolides, quinolones, vancomycin and aminoglycosides. Physicians were more likely to respond incorrectly at baseline than post-intervention for cephalosporins (OR=4.2; IC95%:2.9-6.1; p=0.00001), penicillins (OR=1.9; IC95%:1.2-2.9; p=0.006), quinolones (OR=4.0; IC95%:2.5-6.6; p=0.00001)), macrolides (OR: 4.9 IC95%:3.0-7.9; p= 0,00001 vancomycin (OR=2.2; IC95%: 1.2-4.1; p=0.009) and aminoglycosides (OR=2.1; IC95%:1.3-3.3; p=0.002). Conclusions: Educational interventions for health professionals can improve knowledge when designed to target specific topics, including appropriate antibiotic prescribing practices in health centers. These findings reflect the need to initiate a re-certification process for Dominican physicians, which may impact the quality of attention for the users of health services in the DR.