[Reasons to recommend vaccination against dengue in Easter Island: Immunization Advisory Committee of Sociedad Chilena de Infectología]

Dengue was first diagnosed on Easter Island on year 2002 and thereafter recurrent outbreaks have occurred involving different serotypes of dengue virus. Its vector, Aedes aegypti has not been eliminated despite the small size of the island. Conditions at the local hospital preclude adequate management of severe and hemorrhagic cases due to the absence of a Critical Care Unit as well as no availability of platelets, or plasma units for transfusion. Besides, transfer, of severely affected patients to continental Chile is cumbersome, slow and expensive. In this scenario, it is advisable to implement selective vaccination of Easter Island habitants with an available quadrivalent attenuated dengue vaccine with the aim to reduce hemorrhagic and severe dengue cases. This strategy should not replace permanent efforts to control waste disposal sites, water sources, maintain vector surveillance and increase education of the population.

[Statement of the Advisory Immunization Committee of the Chilean Society of Infectious Diseases on the emergence of serotype 19A pneumococcal infection and the use of pneumococcal conjugated vaccine in Chilean children]

Inclusion of the 10-valent pneumococcal conjugated vaccine (PCV10) in the Chilean infant vaccination Program in 2011 was followed by a reduction of hospital admissions and pneumonia-related deaths in this age group. However, a progressive increase of serotype 19A pneumococcal isolates (not included in PCV10) has been observed. According to the analysis of pneumococcal strains performed by the national reference laboratory of the Institute of Public Health as part of a national surveillance on invasive pneumococcal infections, the relative proportion of serotype 19A isolates increased from <5% before 2010 to 12-23% in years 2014-2015. Serotype 19A represented 4-8% of the isolates in the pre-vaccine era among children less than 2 years, increasing to 25% during 2014. This increase has been documented in two-thirds of the national territory. Aimong children <5 years of age, 25% of 19A serotype isolates from non-meningeal infections were penicillin resistant wheras from meningeal infections near 100% were penicillin resistant. Genetic analysis indicates that 48% of these 19A strains belong to clonal complex 320, recognized for its pandemic potential and high antimicrobial resistance. Among children, most invasive infections secondary to serotype 19A have occurred in patients fully vaccinated with PCV10. These epidemiological changes indicate an increase in invasive pneumococcal infections by serotype 19A in Chile and the need to control this problem by changing the current PCV10 for the PCV13 vaccine containing serotype 19A.

[Geographic distribution of Kawasaki disease throughout Chile]

BACKGROUND

Incidence of Kawasaki disease (KD) in Chile is rising, however the distribution of cases throughout Chile is unknown.

OBJECTIVE

To describe the epidemiology of KD in Chile between years 2001 and 2011, and study the geographic distribution of KD cases throughout the country.

METHODS

We reviewed national hospital discharge databases for KD cases (ICD10 code M30.3) in children < 18 years. KD admission rates per 100,000 children < 5 years were calculated for every commune, health district and region, as a proxy of KD incidence.

RESULTS

1,404 KD cases were registered with a national KD incidence rate of 8.7. KD incidence rate increased significantly from 5.9 in 2001-2003 to 10.4 in 2009-2011 (p < 0.001). Regions IX (Araucanía), Metropolitan and VI (O'Higgins) had the highest KD incidence (12.4, 11.1 and 10.5 respectively), and regions III (Atacama), II (Antofagasta) and XII (Magallanes), had the lowest incidence (0.8, 3.9 and 4, respectively). The Eastern Metropolitan Health District, the population with the highest socioeconomic status in Chile, had the highest KD incidence rate (19.8) and concentrated 23.9% of the country's hospital discharges for KD.

CONCLUSION

KD incidence in Chile is heterogeneous, with concentration of caseloads in the central regions and especially in the Eastern Metropolitan Health District. Geographic variations of KD in Chile could be associated with real differences in incidence or with disparities in diagnostic opportunity, and access to specialists and tertiary healthcare centers.

[Clinical features of Eosinophilic Colitis in infants with persistent rectal bleeding]

The most common presentation of cow's milk protein allergy (CMP) in infants is known as eosinophilic colitis (EC). The aim of this study is to evaluate EC characteristics in infants evaluated with colonoscopy due to the presence of rectorrhagia.

PATIENTS AND METHODS

A retrospective case-control study. Left-sided colonoscopy records of infants with persistent rectal bleeding, conducted between January 2006 and March 2011, were reviewed. The cases corresponded to infants with rectal biopsy compatible with EC and controls with negative biopsy. Telephone questionnaires to parents were conducted, evaluating personal and family history.

RESULTS

Complete records were obtained in 61 (79%) of the 77 procedures. 33 (54%) of them were males. Examination average age was 6.3 ± 5.9 months. 25 (41%) patients had EC on their histology. Between cases and controls, no significant difference in gestational age, birth weight and gender, only regarding age at the time of rectal bleeding, were observed. There was also no difference in personal history regarding obstructive bronchitis, allergic rhinitis, family history of asthma, allergic rhinitis or other food allergies. Those who received artificial feeding did not presented greater risk of EC. The most common symptoms in the cases did not differ significantly from the controls.

CONCLUSIONS

The prevalence of EC in the children studied was 40.9%. Our results show that there are groups of patients with persistent rectal bleeding in which there is no personal or family history that helps diagnosing EC. An endoscopic study could be considered in these patients to establish a correct diagnosis of this condition, avoid unnecessary diets and not to delay the detection of other diseases.

[High rates of overweight and obesity in Chilean children with Down syndrome]

BACKGROUND

Overweight and obesity in Down syndrome (DS) is a common problem. Chile has a high prevalence of DS.

AIM

To determine overweight and obesity rates in students with DS and evaluate the concordance of three different growth charts.

MATERIAL AND METHODS

Seventy nine students with DS aged between 6 and 18 years (56% males), from three different schools, were included. Weight and height were measured and their body mass index (BMI) was calculated. The nutritional diagnosis was made according to BMI. Myrelid SDM/2002, National Center for Health Statistics (NCHS)/2000, World Health Organization (WHO)/2007 charts for people with DS were used.

RESULTS

Thirty percent of participants had hypothyroidism, 22.8% congenital heart disease and 5% asthma. Overweight and obesity rates according to SDM/2002, NCHS/2000 and WHO/2007 were 43, 57 and 66% respectively. The concordance between WHO/2007 and NCHS/2000 was almost perfect, but not with SDM/2002.

CONCLUSIONS

A high rate of overweight and obesity was found in this group of children with DS, independent of the charts used or their comorbidities.

Infection in Health Personnel with High and Low Levels of Exposure in a Hospital Setting during the H1N1 2009 Influenza A Pandemic

A novel H1N1 influenza A virus caused the first pandemic of the 21^st century in 2009. Hospitals had an increased demand of health consultations, that made it difficult to estimate the incidence of infection in hospital personnel due to asymptomatic presentations and the under notification of cases. To estimate and compare the rate of exposure of high versus low risk health personnel to 2009 pandemic H1N1 (H1N1pdm2009) influenza A virus in a University Hospital in Chile, we performed a comparative and prospective study. Serum samples were obtained from 117 individuals that worked in the emergency room (ER) and the operating room (OR) during the peak of the pandemic. Antibody titers were determined by the hemagglutination inhibition (HI) assay. Of the samples analyzed, 65% were workers at the ER and 35% at the OR. Of the total number of the subjects tested, 29.1% were seropositive. One out of 3 (36.8%) workers at the ER had positive HI titers, meanwhile only 1 out of 7 (14.6%) workers from the OR was seropositive to the virus. The possibility of being infected in the ER as compared to the OR was 3.4 times greater (OR 3.4; CI 95%, 1.27–9.1), and the individuals of the ER had almost twice as much antibody titers against H1N1pdm2009 than the personnel in the OR, suggesting the potential of more than one exposure to the virus. Of the 34 seropositive subjects, 12 (35.3%) did not develop influenza like illness, including 2 non-clinical personnel involved in direct contact with patients at the ER. Considering the estimated population attack rate in Chile of 13%, both groups presented a higher exposure and seropositive rate than the general population, with ER personnel showing greater risk of infection and a significantly higher level of antibodies. This data provide a strong rationale to design improved control measures aimed at all the hospital personnel, including those coming into contact with the patients prior to triage, to prevent the propagation and transmission of respiratory viruses, particularly during a pandemic outbreak.

One Health in Practice: A Pilot Project for Integrated Care of Zoonotic Infections in Immunocompromised Children and Their Pets in Chile

Although pets provide physiological and psychological benefits to their owners, they are a potential source of zoonotic infections, especially for vulnerable individuals such as immunocompromised patients. During 1 year, we therefore performed a pilot project, which included 32 immunocompromised Chilean children and their family pets (35 dogs and 9 cats) with the aim of detecting, treating and preventing zoonotic infections. Children were examined by Infectious Diseases paediatricians and demographical and clinical information related to zoonotic infections were recorded. Pets were examined and sampled by veterinarians, who also administered missing routine vaccines and anti-parasitics. During family visits, all members were informed and educated about zoonoses and a satisfaction survey was performed. Visits also included vector control and indoor residual spraying with pyrethroids. Children were re-examined and re-tested according to the findings of their pets, and all detected zoonotic infections were treated both in children and pets. Physical examination revealed abnormalities in 18 dogs (51.4%) and three cats (33.3%). Twenty-eight (63.6%) of the pets were diagnosed with a zoonotic pathogen, and seven (15.9%) with a facultative pathogen. Most zoonotic agents were isolated from the pet's external ear and intestine. Bacteria with the highest pathogenic potential were Campylobacter jejuni and Brucella canis. In two children and their respective pets, the same zoonotic diseases were diagnosed (toxocariasis and giardiasis). Arthropods serving as potential vectors of zoonotic infections were found in 49% of dogs and 44% of cats. The pilot project was positively evaluated by the participating families. Our pilot project confirmed that pets are reservoir for various zoonotic agents in Chile and that the implementation of an integrated multidisciplinary programme was a valuable tool to prevent, diagnose and treat such zoonotic infections in vulnerable patients such as immunocompromised children.

[Clinic and epidemiologic description of Clostridium difficile infection in a pediatric population]

BACKGROUND

Clostridium difficile (CUj-associated disease (CDAD) and the role of the hypervirulent strain NAP1 have not been well characterized in Pediatrics.

AIMS

To describe clinical features of CDAD, and to estimate NAP1 frequency and association with disease severity in Pediatrics.

METHODS

Descriptive, transversal surveillance of diarrheal episodes in Chilean children, hospitalized between February 2012 and December 2013, positive for CD by molecular diagnosis.

RESULTS

A total of 66 episodes of diarrhea with identification of CD occurred thougout the study period in children between 1 month and 19 years of age of which 39% were younger than one year old. CD acquisition was predominantly nosocomial and the most common risk factors were: presence of comorbidities (98.6%), use of antibiotics (93.9%), proton pump inhibitors (84.8%), invasive mechanic ventilation (54.5%), feeding tube (48.5%) and immunosuppression (40.9%). Clinical course was mostly mild, but 12 cases presented an unfavorable course, of which 3/26 occurred in children less than one year. Only one case was positive for NAP1 and had a mild course.

CONCLUSION

Diarrhea with identification of CD was present throughout all pediatric ages, including children less than one year old. Analytical and longitudinal studies are required to better characterize the pathogenic role of CD in this age group. CDAD occurred mostly in patients with risk factors, and the clinical course was predominantly mild.

Vitamin D levels and vitamin D receptor gene polymorphisms in asthmatic children: a case-control study

BACKGROUND

Vitamin D deficiency and single nucleotide polymorphisms (SNP) in the gene encoding vitamin D receptor (VDR) have been associated with asthma.

OBJECTIVE

To compare 25-hydroxyvitamin D (25OHD) levels and the frequency of 3 SNPs in the VDR gene between asthmatic and healthy children.

METHODS

In persistent asthmatic and healthy control children, the 25OHD levels were measured using radioimmunoassay and SNPs (FokI, ApaI, and TaqI) were analyzed by a PCR-RFLP assay. Relevant medical history was collected.

RESULTS

About 75 asthmatic (median age: 9.1 years) and 227 healthy children (10.3 years) were studied. In the whole population, the proportion of sufficient, insufficient, and deficient levels of 25OHD were 14.9%, 44%, and 41.1%, respectively. 25OHD sufficiency status was similar in asthmatic and healthy children (p = 0.57). However, the proportion of 25OHD sufficient levels among asthmatics according to the Global Initiative for Asthma treatment steps 2, 3, and 4 was significantly different (8.6%, 16.6%, and 43.7%, respectively, p = 0.046). All patients on step 4 of the treatment (16/16) were heterozygous for the C allele (FokI VDR SNP). There was a lower presence of the C allele among asthmatics in step 2 (30/33), step 3 (16/24), and controls (45/50), p = 0.007, but this significance did not persist after logistic regression. No significant differences in ApaI and TaqI were found.

CONCLUSIONS

We found a possible association of vitamin D sufficiency status and FokI C allele with higher requirement of therapy to reach asthma control, suggesting that it may be involved in treatment response. Variations in VDR might also play a role in the 25OHD levels.

[Higher risk for health care associated infections in hospitalized children with special health needs]

BACKGROUND

Nosocomial infections (NIs) represent an important public health issue, being associated with high morbidity, mortality and costs.

OBJECTIVES

To identify risk factors of NIs in a cohort of hospitalized pediatric patients, with emphasis in children with special health care needs (CSHCN).

PATIENTS AND METHODS

We studied patients hospitalized in Sótero del Río Pediatric Hospital at Santiago-Chile, between September and December, 2009. Relative Risk (RR) was calculated between CSHCN-3 (children attended by three or more health care professionals) versus non CSHCN-3, and between children with medical complexity (CMC) versus non CMC, using log-binomial models.

RESULTS

920 patients were included. Prevalence of NIs was 12.7%. The most frequent diagnoses were gastrointestinal and respiratory viral infections. Both crude and adjusted by confounders (age and sex), CSHCN-3 and CMC presented significantly higher risk of NIs compared to patients without these conditions (RR 2.91 and RR 2.16, respectively).

CONCLUSION

CSHCN-3 and CMC represent independent conditions associated to a 2-3 fold risk of NIs.

[Odds ratio: theoretical and practical issues]

Odds Ratio (OR) is an effect measure frequently used to communicate results of health research. Mathematically, OR is the quotient between two odds, being odds an alternative way to express possibility of occurrence of an outcome or presence of an exposition. From a methodological perspective, OR can be calculated from prospective, retrospective and cross-sectional designs, and under certain conditions it can replace the Relative Risk. Based on a series of questions and examples, this article explains theoretical and methodological grounds underlying the concept of OR, in order to facilitate its interpretation for clinicians and researchers.

Metabolic syndrome and its components are strongly associated with an inflammatory state and insulin resistance in the pediatric population

INTRODUCTION

Endothelial inflammation and insulin resistance (IR) begin in childhood and constitute the pathophysiological basis of Metabolic Syndrome (MS). The increase levels in plasma of inflammatory markers such as high sensitive PCR (hsPCR), plasminogen activator inhibitor 1 (PAI-1) and tests suggestive of IR such as Insulin (Ins) and alanine aminotransferase (ALT) have been associated with MS in adults, but have not been studied in children.

OBJECTIVES

Correlate the presence of MS and its components with the inflammatory and IR markers seen in the pediatric population.

METHODS

Cross-sectional study of 337 children (10,9±9,7 years) whose levels of hsPCR, PAI-1, Ins and ALT were determined, along with their association with MS and its individual components.

RESULTS

37 children had MS (10,4%). The frequency of MS components was: abdominal obesity 38,5%, hypertension (HTN) 21,3%, hypertriglyceridemia 17,8%, HDL 21,3% and hyperglycemia 1,4%. hsPCR, PAI-1, ALT and Ins were higher in the presence of MS and increased progressively when components were came together.

CONCLUSIONS

The pediatric population segment with MS had a higher concentration of hsPCR, PAI-1, Ins and ALT.These levels increase proportionally MS components add up, suggesting that even before diagnosis criteria are fulfilled there is a inflammatory state.

[Concordance of nasal swabs and nasopharyngeal swabs in the detection of respiratory viruses by direct immunofluorescence]

BACKGROUND

The most used test for the diagnosis of viral respiratory infection is the detection of viral antigens by direct immunofluorescence (DFA), in samples taken by nasopharyngeal swab (NPS) or aspirate (NPA). It would be desirable to have a less uncomfortable technique to obtain a sample from the patient, but of equal performance.

AIM

To evaluate the diagnostic agreement between nasal swab (NS) and nasopharyngeal swab (NPS) in the detection of respiratory viruses by DFA and compare the degree of discomfort of both techniques in pediatric patients.

METHODOLOGY

Cross-sectional study in children who consulted to a pediatric emergency service with respiratory symptoms. Two samples (NPS and NS) per child were collected. The concordance between the two was determined by Kappa (K) coefficient and the degree of discomfort by a visual pain scale.

RESULTS

We obtained 112 samples from 56 children, one by each technique. 82.1% were concordant, K = 0.61 (CI 95%, 0.39-0.83) for the detection of any virus, and K = 0.69 (CI 95%, 0.46-0.92) and K = 0.76 (CI 95%, 0.51-1) for syncytial respiratory virus and influenza A detection, respectively. The degree of discomfort was significantly lower for the NS.

CONCLUSION

There is considerable agreement in the detection of respiratory viruses by DFA between samples obtained by NS and NPS, but not enough to recommend a change in the sampling method in this population.

[Nosocomial infections after cardiac surgery in infants and children with congenital heart disease]

INTRODUCTION

Nosocomial infections generate high morbidity and mortality in children undergoing cardiac surgery.

OBJECTIVE

To determine risk factors for nosocomial infections in children after congenital heart surgery.

METHODS

A retrospective case-control study, in patients younger than 15 years undergoing surgery for congenital heart disease from January 2007 to December 2011 admitted to the Pediatric Critical Patient Unit (UPC-P) in a university hospital. For cases, the information was analyzed from the first episode of infection.

RESULTS

39 patients who develop infections and 39 controls who did not develop infection were enrolled. The median age of cases was 2 months. We identified a number of factors associated with the occurrence of infections, highlighting in univariate analysis: age, weight, univentricular heart physiology, complexity of the surgical procedure according to RACHS-1 and cardiopulmonary bypass (CPB) time ≥ 200 minutes. Multivariate analysis identified CPB time ≥ 200 minutes as the major risk factor, with an OR of 11.57 (CI: 1.04 to 128.5).

CONCLUSION

CPB time ≥ 200 minutes was the mayor risk factor associated with the development of nosocomial infections.

A new way to find evidence quickly and efficiently

Evidence coming from scientific research helps us make better decisions in relation with the care we provide to our patients. Some evidence is more reliable than other is, and systematic reviews are considered the best available evidence for answering questions that compare two or more alternatives of care, as long as they are well conducted and up-to-date. There has lately been a fast growth of the amount of available systematic reviews, so users need to choose between several possible options. Epistemonikos database is a highly efficient search resource, since it groups the larger number of systematic reviews worldwide, and allows accessing the body of evidence for a specific question in a simple and intuitive way. Additionally, it offers tools that enable the choice among different systematic reviews and for keeping the evidence for a question updated with minimal effort.

Higher latitude and lower solar radiation influence on anaphylaxis in Chilean children

BACKGROUND

Recent studies suggest an association between higher latitude, a proxy of vitamin D (VD) status, and allergic diseases. Chile provides an ideal setting to study this association due to its latitude span and high rates of VD deficiency in southern regions. The aim of this study is to explore the associations of latitude and solar radiation with anaphylaxis admission rates.

METHODS

We reviewed anaphylaxis admissions in Chile's hospital discharge database between 2001 and 2010 and investigated associations with latitude and solar radiation.

RESULTS

2316 anaphylaxis admissions were registered. Median age of patients was 41 yr; 53% were female. National anaphylaxis admission rate was 1.41 per 100,000 persons per year. We observed a strong north-south increasing gradient of anaphylaxis admissions (β 0.04, p = 0.01), with increasing rates south of latitude 34°S. A significant association was also observed between solar radiation and anaphylaxis admissions (β -0.11, p = 0.009). Latitude was associated with food-induced (β 0.05, p = 0.02), but not drug-induced (β -0.002, p = 0.27), anaphylaxis. The association between latitude and food-induced anaphylaxis was significant in children (β 0.01, p = 0.006), but not adults (β 0.003, p = 0.16). Anaphylaxis admissions were not associated with regional sociodemographic factors like poverty, rurality, educational level, ethnicity, or physician density.

CONCLUSIONS

Anaphylaxis admission rates in Chile are highest at higher latitudes and lower solar radiation, used as proxies of VD status. The associations appear driven by food-induced anaphylaxis. Our data support a possible role of VD deficiency as an etiological factor in the high anaphylaxis admission rates found in southern Chile.

High sodium intake is associated with increased glucocorticoid production, insulin resistance and metabolic syndrome

OBJECTIVE

High sodium (HS) diet is associated with hypertension (HT) and insulin resistance (IR). We evaluated whether HS diet was associated with a dysregulation of cortisol production and metabolic syndrome (MetS).

PATIENTS AND MEASUREMENTS

We recruited 370 adults (18-85 years, BMI 29·3 ± 4·4 kg/m(2) , 70% women, 72% HT, 61% MetS). HS diet (urinary sodium >150 mEq/day) was observed in 70% of subjects. We measured plasma hormones, lipid profile, urinary free cortisol (UFC) and cortisol tetrahydrometabolites (THM).

RESULTS

Urinary sodium was correlated with UFC (r = +0·45, P < 0·001), cortisol THM (r = +0·41, P < 0·001) and inversely with adiponectin, HDL and aldosterone, after adjusting by age, gender and BMI. Subjects with high, compared with adequate sodium intake (50-149 mEq/day) had higher UFC (P < 0·001), THM (P < 0·001), HOMA-IR (P = 0·04), HT (81% vs 50%, P < 0·001), MetS (69% vs 41%, P < 0·001) and lower adiponectin (P = 0·003). A multivariate predictive model adjusted by confounders showed a high discriminative capacity for MetS (ROC curve 0·878) using four clinical variables: HS intake [OR = 5·6 (CI 2·3-15·3)], HOMA-IR [OR 1·7 (1·3-2·2)] cortisol THM [OR 1·2 (1·1-1·4)] and adiponectin [OR = 0·9 (0·8-0·9)], the latter had a protective effect.

CONCLUSIONS

High sodium diet was associated with increased urinary cortisol and its metabolites. Also, HS diet was associated with HT, insulin resistance, dyslipidaemia and hypoadiponectinaemia, even when adjusting by confounding variables. Further, we observed that high salt intake, IR and higher cortisol metabolites, alone or combined in a clinical simple model, accurately predicted MetS status, suggesting an additive mechanism in obesity-related metabolic disorders.