Evan J. Anderson

Community-Acquired Pneumonia Requiring Hospitalization among U.S. Adults

BACKGROUND Community-acquired pneumonia is a leading infectious cause of hospitalization and death among U.S. adults. Incidence estimates of pneumonia confirmed radiographically and with the use of current laboratory diagnostic tests are needed. METHODS We conducted active population-based surveillance for community-acquired pneumonia requiring hospitalization among adults 18 years of age or older in five hospitals in Chicago and Nashville. Patients with recent hospitalization or severe immunosuppression were excluded. Blood, urine, and respiratory specimens were systematically collected for culture, serologic testing, antigen detection, and molecular diagnostic testing. Study radiologists independently reviewed chest radiographs. We calculated population-based incidence rates of community-acquired pneumonia requiring hospitalization according to age and pathogen. RESULTS From January 2010 through June 2012, we enrolled 2488 of 3634 eligible adults (68%). Among 2320 adults with radiographic evidence of pneumonia (93%), the median age of the patients was 57 years (interquartile range, 46 to 71); 498 patients (21%) required intensive care, and 52 (2%) died. Among 2259 patients who had radiographic evidence of pneumonia and specimens available for both bacterial and viral testing, a pathogen was detected in 853 (38%): one or more viruses in 530 (23%), bacteria in 247 (11%), bacterial and viral pathogens in 59 (3%), and a fungal or mycobacterial pathogen in 17 (1%). The most common pathogens were human rhinovirus (in 9% of patients), influenza virus (in 6%), and Streptococcus pneumoniae (in 5%). The annual incidence of pneumonia was 24.8 cases (95% confidence interval, 23.5 to 26.1) per 10,000 adults, with the highest rates among adults 65 to 79 years of age (63.0 cases per 10,000 adults) and those 80 years of age or older (164.3 cases per 10,000 adults). For each pathogen, the incidence increased with age. CONCLUSIONS The incidence of community-acquired pneumonia requiring hospitalization was highest among the oldest adults. Despite current diagnostic tests, no pathogen was detected in the majority of patients. Respiratory viruses were detected more frequently than bacteria. (Funded by the Influenza Division of the National Center for Immunizations and Respiratory Diseases.).

Rotavirus vaccines: viral shedding and risk of transmission

Rotavirus causes gastroenteritis in almost all children by 5 years of age. Immunity to rotavirus is incomplete, with potential for recurrent infections occurring throughout life. Live rotavirus vaccines have been developed for the protection of children from severe wildtype rotavirus infections. Transmission of vaccine virus strains from vaccinated children to unvaccinated contacts harbours the potential for herd immunity, but also the risk of vaccine-derived disease in immunocompromised contacts. A review of rotavirus vaccine prelicensure studies shows that viral shedding and transmission were higher with the old tetravalent rhesus rotavirus vaccine than with the current human attenuated monovalent rotavirus vaccine and the pentavalent bovine-human reassortant vaccine. Immunocompromised contacts should be advised to avoid contact with stool from the immunised child if possible, particularly after the first vaccine dose for at least 14 days. Since the risk of vaccine transmission and subsequent vaccine-derived disease with the current vaccines is much less than the risk of wildtype rotavirus disease in immunocompromised contacts, vaccination should be encouraged.

High-risk adenovirus-infected pediatric allogeneic hematopoietic progenitor cell transplant recipients and preemptive cidofovir therapy.

Abstract:  ADV has emerged as an important pathogen in children undergoing allogeneic HPCT. A prospective study of the epidemiology of ADV infection and preemptive therapy of high risk ADV infections in children undergoing HPCT was undertaken. Cultures of throat, urine, and stool for viral pathogens and plasma for ADV PCR were obtained prior to transplantation, weekly for the first 100 days, and then monthly for one yr. Children developing high‐risk ADV infections were treated preemptively with cidofovir 1 mg/kg/day given three times weekly for three wk. A case‐controlled study was performed to identify risk factors for high‐risk ADV infections. Seven (18%) of the 38 subjects developed high‐risk ADV infections usually within 100 days of HPCT and were preemptively treated with i.v. cidofovir at a dose of 1 mg/kg/dose three times weekly for nine doses. High‐risk ADV infections resolved in all seven patients without renal toxicity. CMV viremia occurred in two of seven patients during or shortly after therapy with cidofovir. A case–control study did not identify any risk factors that achieved statistical significance. Treatment with a modified dosing regimen of cidofovir was well‐tolerated and high‐risk ADV infections resolved in all patients.

Impact of Rotavirus Vaccination on Hospital-Acquired Rotavirus Gastroenteritis in Children

OBJECTIVE: Data show that after the implementation of routine rotavirus vaccination for infants in the United States, community-acquired (CA) rotavirus cases declined substantially in the 2007–2008 season. The impact of community-based rotavirus vaccination on the substantial burden of hospital-acquired (HA) rotavirus has not been documented. PATIENTS AND METHODS: We assessed CA and HA rotavirus, respiratory syncytial virus, and influenza infections at Childrens Memorial Hospital for 5 winter seasons (defined as occurring from September through May) from 2003 to 2008. We also report rotavirus data from the 2008–2009 season. RESULTS: A similar dramatic decline (>60% compared with the median of previous seasons) occurred in the rates of cases of both CA (P < .0001) rotavirus hospitalizations and HA (P < .01) rotavirus infections in the 2007–2008 season compared with previous seasons, whereas the rates of CA and HA influenza and respiratory syncytial virus, respectively, remained stable. Improvements in hand-hygiene compliance did not correlate with a reduction in the transmission rate of rotavirus in the hospital. Both CA and HA rotavirus rates remained much lower in the 2008–2009 than in the 2003–2007 seasons. CONCLUSIONS: Community-based rotavirus vaccination is associated with a substantial reduction in the number of children who are admitted with rotavirus. These data also indicate that routine community-based rotavirus infant vaccination protects hospitalized children from acquiring rotavirus. Vaccination efforts should be encouraged as a strategy to affect the substantial burden of HA rotavirus.

Prevention and treatment of viral diarrhea in pediatrics

Diarrhea is the second largest cause of mortality worldwide in children from the perinatal period to the age of 5 years. Rotavirus has been the most commonly identified viral cause of diarrhea in children. Norovirus is now recognized as the second most common viral pathogen. Adenovirus, astrovirus and sapovirus are the other major viral causes of pediatric gastroenteritis. Strategies for prevention include basic hygiene, optimization of nutrition and, ultimately, vaccination. Two new vaccines have recently been licensed for the prevention of rotavirus, the monovalent human rotavirus vaccine (Rotarix™) and the pentavalent bovine–human reassortant vaccine (RotaTeq®). These vaccines have already dramatically decreased the morbidity associated with rotavirus in countries where they are widely used. Efforts to develop a norovirus vaccine face substantial hurdles. Treatment of the viral pathogens is primarily limited to symptomatic measures.

Identification of Adenoviruses in Specimens from High-Risk Pediatric Stem Cell Transplant Recipients and Controls

ABSTRACT Adenovirus infection is an important cause of morbidity and mortality in stem cell transplant recipients. We report species and type-specific analysis from a prospective study of high-risk adenovirus infections following hematopoietic progenitor cell transplantation prior to, during, and after treatment with cidofovir, as well as species analysis of contemporaneously collected samples from control patients. Nine different adenovirus types representing all six recognized species were identified, and mixed infections were commonly found in this group of patients.

A multicenter retrospective study of childhood brucellosis in Chicago, Illinois from 1986 to 2008.

OBJECTIVES To determine risk factors in children for the acquisition of Brucella, clinical presentation, treatment, and disease outcomes. METHODS A retrospective multicenter chart review was undertaken of children identified with brucellosis from 1986 to 2008 at three tertiary care centers in Chicago, Illinois, USA. The charts were reviewed for data regarding risk factors for acquisition, clinical presentation, and outcomes. RESULTS Twenty-one charts were available for review. The median age was 6.5 years (range 2-14 years); 62% were female. Ethnic background was 67% Hispanic and 24% Arabic. Risk factors included travel to an endemic area (86%), particularly Mexico, and consumption of unpasteurized milk products (76%). Common findings included fever (95%), bacteremia (86%), elevated liver transaminases (80%), constitutional symptoms (76%), splenomegaly (60%), and hepatomegaly (55%). Relapse occurred in three of six subjects started on single drug treatment, but in only one of 15 subjects who started on two or more drugs (p=0.053). No relapses occurred in children whose initial therapy included rifampin or those administered three-drug regimens. CONCLUSIONS Brucella is an infrequent pathogen but should be considered in children with compatible epidemiologic and clinical characteristics. Blood cultures should be obtained, and initial therapy with two or more drugs may decrease the risk of relapse.

Multicenter clinical performance evaluation of BD Veritor™ System for Rapid Detection of Respiratory Syncytial Virus

BACKGROUND BD Veritor™ System for Rapid Detection of Respiratory Syncytial Virus (RSV) is a new-generation lateral flow immunochromatographic assay for objective detection of RSV in respiratory specimens from children. OBJECTIVE To evaluate the performance of BD Veritor™ System for Rapid Detection of RSV in respiratory specimens collected from pediatric patients. STUDY DESIGN A prospective, multicenter clinical trial was undertaken at five study sites representing geographically diverse regions of the U.S. to assess the performance of the BD Veritor™ System for Rapid Detection of RSV in comparison to R-mix shell vial culture and ProFlu+ reverse transcription-PCR assay (Gen-Probe/Prodesse). RESULTS 440 nasopharyngeal washes/aspirates (NPW/A) and 706 nasopharyngeal swab (NPS) specimens from U.S. subjects<20 years of age were collected and tested using the BD Veritor™ System and compared with shell vial culture and real-time RT-PCR results. Analysis of the data indicates the overall sensitivity and specificity for BD Veritor™ System for all sample types combined was 90% and 97.0% versus shell vial culture and 75.5% and 98.7% versus RT-PCR respectively. CONCLUSION Overall, the BD Veritor™ System for the Rapid Detection of RSV performed well when compared to both viral cell culture and RT-PCR in children.

Echocardiography in pediatric infective endocarditis.

Transesophageal echocardiography is more sensitive than transthoracic echocardiography (TTE) in detecting endocarditis in adults; however, pediatric data are limited. Retrospectively, 39 subjects with endocarditis were divided into adult-sized (≥60 kg) and pediatric-sized (<60 kg). TTE was 97% sensitive in pediatric-sized subjects but 70% in adult-sized subjects (P < 0.05). TTE is usually sufficient for detection of endocarditis in children <60 kg.

Blastomycosis in Children: A Study of 14 Cases

We retrospectively reviewed 14 children with active blastomycosis. Pulmonary disease occurred in 86% of the cohort and extrapulmonary dissemination was noted in 46%. Urine blastomycosis or histoplasmosis antigens were positive in all tested patients. Acute kidney injury was common in patients who were treated with amphotericin. Mortality tended to be associated with a delay in diagnosis.