Group A Streptococcus pharyngitis in Children: New Perspectives on Rapid Diagnostic Testing and Antimicrobial Stewardship.

The most common cause of bacterial pharyngitis is Group A Streptococcus (GAS). Accurate diagnosis of GAS pharyngitis is crucial to identify children who would benefit from antibiotic treatment. Rapid diagnosis has the potential to reduce antibiotic overuse. Current national guidelines differ in their recommendations for GAS testing. While rapid antigen detection tests (RADTs) are widely used, their sensitivity is considered too low for stand-alone testing by several expert bodies. Newer molecular tests using nucleic acid amplification show higher accuracy and fast results, but their cost, complexity, and very high sensitivity may limit widespread adoption. This review provides up-to-date evidence regarding rapid diagnostic testing and antimicrobial stewardship in children with sore throat. We discuss discrepancies across GAS testing guidelines at the international level, patient selection for testing for GAS, rapid test accuracy, and the potential role of rapid GAS tests to promote antibiotic stewardship, with emphasis on emerging rapid molecular tests.

Analysis of Plasmablasts From Children With Kawasaki Disease Reveals Evidence of a Convergent Antibody Response to a Specific Protein Epitope.

BACKGROUND: Kawasaki disease (KD) is a febrile illness of young childhood that can result in coronary artery aneurysms and death. Coronavirus disease 2019 (COVID-19) mitigation strategies resulted in a marked decrease in KD cases worldwide, supporting a transmissible respiratory agent as the cause. We previously reported a peptide epitope recognized by monoclonal antibodies (MAbs) derived from clonally expanded peripheral blood plasmablasts from 3 of 11 KD children, suggesting a common disease trigger in a subset of patients with KD. METHODS: We performed amino acid substitution scans to develop modified peptides with improved recognition by KD MAbs. We prepared additional MAbs from KD peripheral blood plasmablasts and assessed MAb characteristics that were associated with binding to the modified peptides. RESULTS: We report a modified peptide epitope that is recognized by 20 MAbs from 11 of 12 KD patients. These MAbs predominantly use heavy chain VH3-74; two-thirds of VH3-74 plasmablasts from these patients recognize the epitope. The MAbs were nonidentical between patients but share a common complementarity-determining region 3 (CDR3) motif. CONCLUSIONS: These results demonstrate a convergent VH3-74 plasmablast response to a specific protein antigen in children with KD, supporting one predominant causative agent in the etiopathogenesis of the illness.

Monkeypox Emergence and the Eradication of Smallpox: An Historical Review.

BACKGROUND: Human monkeypox infection was first identified in 1970 in African. Small rodents were the natural reservoir of this orthopoxvirus, with humans and primates as incidental hosts. Smallpox vaccination induces cross protection against monkeypox. In Africa monkeypox overlapped with the Global Smallpox Eradication Program (GSEP) six decades ago. The 2022 human monkeypox epidemic prompted literature review re potential impact of monkeypox upon GSEP efforts. METHODS: Literature review from 1960 to present related to GSEP launched in 1969 with particular focus on monkeypox epidemiology during planning of GSEP in the 1960's through 1989 including surveillance years later. RESULTS: Establishing the lack of a non-human reservoir of smallpox was essential to assessing the GSEP because of the similarity of the two orthopoxviruses. It was found that a non-human smallpox reservoir was highly remote. Human monkeypox did not occur in smallpox-vaccinated humans and was limited to non-vaccinees. Surveillance in Democratic Republic of the Congo (DRC) until 1989 found monkeypox was very unlikely to persist in humans and unlikely to become a major public health problem. From 2005-2007, decades after cessation of smallpox vaccination, monkeypox surveillance in DRC revealed 20-fold higher incidence of human monkeypox correlated with much lower rates of prior smallpox vaccination. CONCLUSIONS: Human monkeypox rates in DRC were 20-fold higher decades after cessation of smallpox vaccination compared to when smallpox vaccination was still used. The resultant decreased cross-protection against monkeypox contributed to the 2022 multinational outbreak of human monkeypox.

Performance of a Molecular Test for Group A Streptococcus Pharyngitis.

We performed a prospective study to determine if the pretest probability of a positive loop-mediated isothermal amplification test is greater when there are more signs and symptoms of GAS pharyngitis. Patients were enrolled if a clinician obtained a GAS RADT. The McIsaac score was calculated. The prevalence of positive LAMP and RADT results increased as the McIsaac score increased. The calculated sensitivity of LAMP was superior to RADT.

Standardization of Epidemiological Surveillance of Group A Streptococcal Pharyngitis.

Pharyngitis, more commonly known as sore throat, is caused by viral and/or bacterial infections. Group A Streptococcus (Strep A) is the most common bacterial cause of pharyngitis. Strep A pharyngitis is an acute, self-limiting disease but if undertreated can lead to suppurative complications, nonsuppurative poststreptococcal immune-mediated diseases, and toxigenic presentations. We present a standardized surveillance protocol, including case definitions for pharyngitis and Strep A pharyngitis, as well as case classifications that can be used to differentiate between suspected, probable, and confirmed cases. We discuss the current tests used to detect Strep A among persons with pharyngitis, including throat culture and point-of-care tests. The type of surveillance methodology depends on the resources available and the objectives of surveillance. Active surveillance and laboratory confirmation is the preferred method for case detection. Participant eligibility, the surveillance population and additional considerations for surveillance of pharyngitis are addressed, including baseline sampling, community engagement, frequency of screening and season. Finally, we discuss the core elements of case report forms for pharyngitis and provide guidance for the recording of severity and pain associated with the course of an episode.

Chronic Granulomatous Disease: an Updated Experience, with Emphasis on Newly Recognized Features.

PURPOSE: Chronic granulomatous disease (CGD) is an uncommon, inborn error of immunity. We updated our large, single-center US experience with CGD and describe some newly recognized features. METHODS: We retrospectively reviewed 26 patients seen from November 2013 to December 2019. Serious infections required intravenous antibiotics or hospitalization. RESULTS: There were 21 males and 5 females. The most frequent infectious agents at presentation were aspergillus (4), serratia (4), burkholderia (2), Staphylococcus aureus (2), and klebsiella (2). The most common serious infections at presentation were pneumonia (6), lymphadenitis (6), and skin abscess (3). Our serious infection rate was 0.2 per patient-year from December 2013 through November 2019, down from 0.62 per patient-year from the previous study period (March 1985-November 2013). In the last 6 years, four patients were evaluated for human stem cell transplantation, two were successfully transplanted, and we had no deaths. Several patients had unusual infections or autoimmune manifestations of disease, such as pneumocystis pneumonia, basidiomycete/phellinus fungal pneumonia, and retinitis pigmentosa. We included one carrier female with unfavorable Lyonization in our cohort. CONCLUSION: We update of a large US single-center experience with CGD and describe some recently identified features of the illness.

Congenital and Perinatal Tuberculosis.

This review discusses the recent literature (2006-2020) about the epidemiology, clinical presentation, diagnosis, and management of infants with congenital or perinatal tuberculosis (TB). While the incidence of childhood TB is declining in the United States and worldwide, many case reports describe how clinical suspicion for neonatal TB is raised only if an ill-appearing neonate does not improve with broad-spectrum antibiotics. Furthermore, the delay in initiating appropriate anti-TB therapy often results in the need for significant cardiopulmonary support and/or an increase in mortality. This review summarizes important clinical indications in the maternal and newborn history, the evaluation of an infant with possible TB exposure, and step-by-step recommendations for the treatment and follow-up of infants with TB.

The Impact of Social Distancing for COVID-19 Upon Diagnosis of Kawasaki Disease.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mitigation policies have been associated with profound decreases in diagnoses of common childhood respiratory infections. A leading theory of etiology of Kawasaki disease (KD) is that it is triggered by presently unidentified ubiquitous respiratory agent. We document that mitigation policies instituted in mid-March 2020 were associated with strikingly fewer diagnoses of KD in April-December 2020 compared with the same period in the previous 8 years (P = .01), a >67% decline. This finding supports the hypothesis that KD is caused by a respiratory-transmitted agent.