Serotypes of Streptococcus pneumoniae in Children Aged <5 Years Hospitalized With or Without Pneumonia in Developing and Emerging Countries: A Descriptive, Multicenter Study.

BACKGROUND: Improving knowledge regarding Streptococcus pneumoniae distribution in pneumonia cases is important to better target preventive and curative measures. The objective was to describe S. pneumoniae serotypes in children with or without pneumonia. METHODS: It was a case-control study carried out in 8 developing and emerging countries between 2010 and 2014. Cases were children aged <5 years admitted to the hospital for pneumonia. Controls were children admitted for surgery or routine outpatient care. RESULTS: In nasopharyngeal samples, S. pneumoniae were detected in 68.2% of the cases and 47.5% of the controls (P < .001). Nasopharyngeal carriage was associated with a higher risk of being a case in 6/8 study sites (adjusted odds ratio ranged from 0.71 [95% confidence interval [CI], .39-1.29; P = .26] in India [Pune/Vadu] to 11.86 [95% CI, 5.77-24.41; P < .001] in Mongolia). The 13-valent pneumococcal conjugate vaccine (PCV13) serotypes were more frequently detected in cases with nasopharyngeal carriage (67.1%) than in controls with nasopharyngeal carriage (54.6%), P < .001. Streptococcus pneumoniae was detected in blood by polymerase chain reaction in 8.3% of the cases. Of 34 cases with an S. pneumoniae serotype detected in blood, 27 (79%) had the same serotype in the nasopharyngeal sample. CONCLUSIONS: The results confirm the assumption that the isolate carrying or causing disease in an individual is of the same serotype. Most serotypes independently associated with nasopharyngeal carriage or pneumonia are covered by PCV13, suggesting that increased PCV coverage would reduce the burden of S. pneumoniae-related pneumonia.

External quality assessment (EQA) and alternative assessment procedures (AAPs) in molecular diagnostics: findings of an international survey.

Objectives: Quality management for clinical laboratories requires the establishment of internal procedures including standard operating procedures (SOPs), internal quality control (QC), validation of test results and quality assessment. External quality assessment (EQA) and alternativeassessment procedures (AAPs) are part of the quality hierarchy required for diagnostic testing. The International Organization for Standardization (ISO) document with requirements for conformance ISO 15189 and the Clinical and Laboratory Standards Institute document (CLSI) QMS24 require participation in EQA schemes and AAPs where applicable. The purpose of this study was to perform a global survey of EQA and AAPs for key procedures in molecular diagnostic laboratories. Methods: The Committee for Molecular Diagnostics of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC C-MD) conducted a survey of international molecular laboratories that covered specific topics of molecular diagnostic services as well as methods for EQA and AAPs. The survey addressed the following aspects: (1) usage of laboratory-developed test (LDT), (2) participation in EQA schemes and (3) performance of AAPs. Results: A total of 93 responses from laboratories located in Asia, Europe, the Middle East, North America and South America were received. The majority of the participating laboratories (65.9%) use LDTs and 81.3% stated that it is mandatory for them to participate in EQA programs, while 22% of the laboratories reported not performing AAPs. Thirty-one percent of the laboratories use EQAs for fewer than 50.0% of their reported parameters/analytes. Conclusions: While the majority of laboratories perform EQA and AAPs to improve their quality in molecular diagnostics, the amount of AAPs as quality procedures differs within the laboratories. Further surveys are necessary to clarify the existing needs in additional EQAs and standardized AAPs. The survey will also guide future efforts of the IFCC C-MD for identifying quality practices in need to improve harmonization and standardization within molecular diagnostics.

Exploring the "Latin American Mediterranean" family and the RDRio lineage in Mycobacterium tuberculosis isolates from Paraguay, Argentina and Venezuela.

BACKGROUND: The Latin American & Mediterranean (LAM) spoligotype family is one of the most successful genotype of Mycobacterium tuberculosis worldwide and particularly prevalent in South-America. Within this family, a sublineage named Region of Difference Rio (RDRio) was reported initially in Brazil and is characterized by a genomic deletion of about 26.3 kb. This lineage seems to show a specific adaptation to the Euro-Latin American population. In this context, we sought to evaluate the LAM family and the presence of the RDRio genotype in samples from three Latin American countries including Paraguay, Venezuela and Argentina. To detect LAM strains reliably we applied a typing scheme using spoligotyping, 12 loci MIRU-VNTR, the Ag85C103 SNP and the regions of difference RDRio and RD174. IS6110-RFLP results were also used when available. RESULTS: Genotyping of 413 M. tuberculosis isolates from three Latin-American countries detected LAM (46%) and the ill-defined T clade (16%) as the most frequent families. The highest clustering rate was detected in the sample population from the city of Caracas in Venezuela. We observed considerable differences in the presence of the RDRio lineage, with high frequency in Caracas-Venezuela (55%) and low frequency in Buenos Aires-Argentina (11%) and Paraguay (10%). The molecular markers (RD174, Ag85C103, MIRU02-MIRU40 signature) of the RDRio lineage were essentially confirmed. For the LAM family, the most polymorphic loci were MIRU40, MIRU31, MIRU10, MIRU26, MIRU16 and the least polymorphic MIRU24, MIRU20, MIRU04, MIRU23. CONCLUSIONS: Our results suggest a differential adaptation of LAM-sublineages in neighboring populations and that RDRio strains spread regionally with different rates of distribution. The Ag85C SNP and RDs (RD174, RDRio) tested in this study can in fact facilitate molecular epidemiological studies of LAM strains in endemic settings and low-income countries.

Toward harmonization of clinical molecular diagnostic reports: findings of an international survey.

BACKGROUND: The International Organization for Standardization (ISO) 15189 standard provides recommendations for the postexamination reporting phase to enhance quality in clinical laboratories. The purpose of this study was to encourage a broad discussion on current reporting practices for molecular diagnostic tests by conducting a global survey of such practices. METHODS: The International Federation of Clinical Chemistry and Laboratory Medicine's Committee for Molecular Diagnostics (IFCC C-MD) surveyed laboratories on selected ISO 15189 recommendations and topics. The survey addressed the following aspects: (1) laboratory demographics, (2) report format, (3) result reporting/layout, (4) comments in report and (5) interpretation and clinical decision-making information. Additionally, participants indicated categories needing standardization. RESULTS: Sixteen responses from laboratories located in Asia, Europe, the Middle East, North America and South America were received. Several categories yielded 100% agreement between laboratories, whereas other categories had less than or equal to 50% concordance. Participants scored "nomenclature" and "description of methodologies" as the two most frequently cited aspects needing standardization. CONCLUSIONS: The postexamination phase requires extensive and consistent communication between the laboratory, the healthcare provider and the end user. Surveyed laboratories were most likely to follow explicit ISO 15189 recommendations vs. recommendations when the term(s) "where appropriate or where applicable" was used. Interpretation and reporting of critical values varied among participants. Although the outcome of this study may not fully represent the practices of all molecular testing laboratories in countries around the world, the survey identified and specified several recommendations that are requirements for harmonized reporting in molecular diagnostics.

Microorganisms Associated With Pneumonia in Children <5 Years of Age in Developing and Emerging Countries: The GABRIEL Pneumonia Multicenter, Prospective, Case-Control Study.

Background: Pneumonia, the leading infectious cause of child mortality globally, mainly afflicts developing countries. This prospective observational study aimed to assess the microorganisms associated with pneumonia in children aged <5 years in developing and emerging countries. Methods: A multicenter, case-control study by the GABRIEL (Global Approach to Biological Research, Infectious diseases and Epidemics in Low-income countries) network was conducted between 2010 and 2014 in Cambodia, China, Haiti, India (2 sites), Madagascar, Mali, Mongolia, and Paraguay. Cases were hospitalized children with radiologically confirmed pneumonia; controls were children from the same setting without any features suggestive of pneumonia. Nasopharyngeal swabs were collected from all subjects; 19 viruses and 5 bacteria were identified by reverse-transcription polymerase chain reaction. Associations between microorganisms and pneumonia were quantified by calculating the adjusted population attributable fraction (aPAF) after multivariate logistic regression analysis adjusted for sex, age, time period, other pathogens, and site. Results: Overall, 888 cases and 870 controls were analyzed; ≥1 microorganism was detected in respiratory samples in 93.0% of cases and 74.4% of controls (P < .001). Streptococcus pneumoniae, Mycoplasma pneumoniae, human metapneumovirus, rhinovirus, respiratory syncytial virus (RSV), parainfluenza virus 1, 3, and 4, and influenza virus A and B were independently associated with pneumonia; aPAF was 42.2% (95% confidence interval [CI], 35.5%-48.2%) for S. pneumoniae, 18.2% (95% CI, 17.4%-19.0%) for RSV, and 11.2% (95% CI, 7.5%-14.7%) for rhinovirus. Conclusions: Streptococcus pneumoniae, RSV, and rhinovirus may be the major microorganisms associated with pneumonia infections in children <5 years of age from developing and emerging countries. Increasing S. pneumoniae vaccination coverage may substantially reduce the burden of pneumonia among children in developing countries.

Computational analysis of a species D human adenovirus provides evidence of a novel virus.

A human adenovirus (HAdV) species D, was isolated from a hospitalised child with severe lower respiratory infection. It was initially detected in the nasopharyngeal aspirate of the child followed by conventional PCR amplification of the hexon, penton base, and fibre genes. Sanger DNA sequencing and phylogenetic analyses showed characteristics of a recombinant genome not described before. Next Generation Sequencing analysis was performed to reconstruct its complete DNA genome after viral isolation in adenocarcinoma human cell line (A549). A complete genomic sequence of 35.2 kb in length, with a G+C content of 57 % was obtained, related to HAdV-D29 (96 % identity). Imputed serology analysis demonstrated its novel type with a nucleotide sequence identity of 95.3 % (hexon loop 1) and 96 % (hexon loop 2) to HAdV-D9. The penton base gene showed a novel sequence, distantly related to HAdV-D44. The E3 and E4 regions evolved significantly from their ancestors. The fibre gene was almost identical to the knob region of HAdV-D15 but showed an unrelated shaft sequence. In conclusion the genomics of this novel HAdV, designated the HAdV-D83 [P83H9F15] prototype and bearing a new penton base gene, supports the importance of viral evolution to understand modified tissue tropism, enhanced transmission, or altered virulence.

Chagas disease: national survey of seroprevalence in children under five years of age conducted in 2008.

BACKGROUND: Since the early 1990s, programs to control Chagas disease in South America have focused on eradicating domiciliary Triatoma infestans, the main vector. Seroprevalence studies of the chagasic infection are included as part of the vector control programs; they are essential to assess the impact of vector control measures and to monitor the prevention of vector transmission. OBJECTIVE: To assess the interruption of domiciliary vector transmission of Chagas disease by T. infestans in Paraguay by evaluating the current state of transmission in rural areas. METHODS: A survey of seroprevalence of Chagas disease was carried out in a representative sample group of Paraguayans aged one to five years living in rural areas of Paraguay in 2008. Blood samples collected on filter paper from 12,776 children were tested using an enzyme-linked immunosorbent assay. Children whose serology was positive or undetermined (n = 41) were recalled to donate a whole blood sample for retesting. Their homes were inspected for current triatomine infestation. Blood samples from their respective mothers were also collected and tested to check possible transmission of the disease by a congenital route. FINDINGS: A seroprevalence rate of 0.24% for Trypanosoma cruzi infection was detected in children under five years of age among the country's rural population. Our findings indicate that T. cruzi was transmitted to these children vertically. The total number of infected children, aged one to five years living in these departments, was estimated at 1,691 cases with an annual incidence of congenital transmission of 338 cases per year. MAIN CONCLUSION: We determined the impact of vector control in the transmission of T. cruzi, following uninterrupted vector control measures employed since 1999 in contiguous T. infestans-endemic areas of Paraguay, and this allowed us to estimate the degree of risk of congenital transmission in the country.

A SNP in the ABCC11 gene is the determinant of human earwax type.

Human earwax consists of wet and dry types. Dry earwax is frequent in East Asians, whereas wet earwax is common in other populations. Here we show that a SNP, 538G --> A (rs17822931), in the ABCC11 gene is responsible for determination of earwax type. The AA genotype corresponds to dry earwax, and GA and GG to wet type. A 27-bp deletion in ABCC11 exon 29 was also found in a few individuals of Asian ancestry. A functional assay demonstrated that cells with allele A show a lower excretory activity for cGMP than those with allele G. The allele A frequency shows a north-south and east-west downward geographical gradient; worldwide, it is highest in Chinese and Koreans, and a common dry-type haplotype is retained among various ethnic populations. These suggest that the allele A arose in northeast Asia and thereafter spread through the world. The 538G --> A SNP is the first example of DNA polymorphism determining a visible genetic trait.

Multicenter case-control study protocol of pneumonia etiology in children: Global Approach to Biological Research, Infectious diseases and Epidemics in Low-income countries (GABRIEL network).

BACKGROUND: Data on the etiologies of pneumonia among children are inadequate, especially in developing countries. The principal objective is to undertake a multicenter incident case-control study of <5-year-old children hospitalized with pneumonia in developing and emerging countries, aiming to identify the causative agents involved in pneumonia while assessing individual and microbial factors associated with the risk of severe pneumonia. METHODS/DESIGN: A multicenter case-control study, based on the GABRIEL network, is ongoing. Ten study sites are located in 9 countries over 3 continents: Brazil, Cambodia, China, Haiti, India, Madagascar, Mali, Mongolia, and Paraguay. At least 1,000 incident cases and 1,000 controls will be enrolled and matched for age and date. Cases are hospitalized children <5 years with radiologically confirmed pneumonia, and the controls are children without any features suggestive of pneumonia. Respiratory specimens are collected from all enrolled subjects to identify 19 viruses and 5 bacteria. Whole blood from pneumonia cases is being tested for 3 major bacteria. S. pneumoniae-positive specimens are serotyped. Urine samples from cases only are tested for detection of antimicrobial activity. The association between procalcitonin, C-reactive protein and pathogens is being evaluated. A discovery platform will enable pathogen identification in undiagnosed samples. DISCUSSION: This multicenter study will provide descriptive results for better understanding of pathogens responsible for pneumonia among children in developing countries. The identification of determinants related to microorganisms associated with pneumonia and its severity should facilitate treatment and prevention.

C1q and HBHA-specific IL-13 levels as surrogate plasma biomarkers for monitoring tuberculosis treatment efficacy: a cross-sectional cohort study in Paraguay.

Introduction: New diagnostic tools are needed to rapidly assess the efficacy of pulmonary tuberculosis (PTB) treatment. The aim of this study was to evaluate several immune biomarkers in an observational and cross-sectional cohort study conducted in Paraguay. Methods: Thirty-two patients with clinically and microbiologically confirmed PTB were evaluated before starting treatment (T0), after 2 months of treatment (T1) and at the end of treatment (T2). At each timepoint plasma levels of IFN-y, 17 pro- and anti-inflammatory cytokines/chemokines and complement factors C1q, C3 and C4 were assessed in unstimulated and Mtb-specific stimulated whole blood samples using QuantiFERON-TB gold plus and recombinant Mycobacterium smegmatis heparin binding hemagglutinin (rmsHBHA) as stimulation antigen. Complete blood counts and liver enzyme assays were also evaluated and correlated with biomarker levels in plasma. Results: In unstimulated plasma, C1q (P<0.001), C4 (P<0.001), hemoglobin (P<0.001), lymphocyte proportion (P<0.001) and absolute white blood cell count (P=0.01) were significantly higher in PTB patients at baseline than in cured patients. C1q and C4 levels were found to be related to Mycobacterium tuberculosis load in sputum. Finally, a combinatorial analysis identified a plasma host signature comprising the detection of C1q and IL-13 levels in response to rmsHBHA as a tool differentiating PTB patients from cured TB profiles, with an AUC of 0.92 (sensitivity 94% and specificity 79%). Conclusion: This observational study provides new insights on host immune responses throughout anti-TB treatment and emphasizes the role of host C1q and HBHA-specific IL-13 response as surrogate plasma biomarkers for monitoring TB treatment efficacy.

Phylogeny-based classification of human rhinoviruses detected in hospitalized children with acute lower respiratory infection in Paraguay, 2010-2011.

Human rhinovirus (HRV), a single-stranded, positive-sense RNA virus, is associated with mild upper respiratory tract infections in children. The aim of this study was to carry out a molecular characterization and phylogeny-based classification of the circulating genotypes of HRV in hospitalized children with clinical manifestations of acute lower respiratory infection in Paraguay. Nasopharyngeal aspirates were collected from 101 children under 5 years of age, hospitalized with symptoms of acute lower respiratory infection, between May 2010 and December 2011, at the largest public pediatric hospital in the Central Department of Paraguay. Detection was performed by a real-time polymerase chain reaction, followed by conventional amplification of the VP4/VP2 genomic region, sequencing, and phylogenetic analysis. Rhinovirus was detected in 33.7% of the samples. Amplification of 18 samples showed the presence of all three species (HRV-A, -B, and -C). Different genotypes were found for each species: 11 for HRV-A (-9, -12, -22, -30, -36, -43, -59, -61, -68, -88, and -89), one for HRV-B (-4), and four for HRV-C (-C2, -C3, -C6, and -C9). In South America, information about HRV diversity is scarce. This is the first report on HRV genotype diversity in South America.

In-hospital mortality risk stratification in children aged under 5 years with pneumonia with or without pulse oximetry: A secondary analysis of the Pneumonia REsearch Partnership to Assess WHO REcommendations (PREPARE) dataset.

OBJECTIVES: We determined the pulse oximetry benefit in pediatric pneumonia mortality risk stratification and chest-indrawing pneumonia in-hospital mortality risk factors. METHODS: We report the characteristics and in-hospital pneumonia-related mortality of children aged 2-59 months who were included in the Pneumonia Research Partnership to Assess WHO Recommendations dataset. We developed multivariable logistic regression models of chest-indrawing pneumonia to identify mortality risk factors. RESULTS: Among 285,839 children, 164,244 (57.5%) from hospital-based studies were included. Pneumonia case fatality risk (CFR) without pulse oximetry measurement was higher than with measurement (5.8%, 95% confidence interval [CI] 5.6-5.9% vs 2.1%, 95% CI 1.9-2.4%). One in five children with chest-indrawing pneumonia was hypoxemic (19.7%, 95% CI 19.0-20.4%), and the hypoxemic CFR was 10.3% (95% CI 9.1-11.5%). Other mortality risk factors were younger age (either 2-5 months [adjusted odds ratio (aOR) 9.94, 95% CI 6.67-14.84] or 6-11 months [aOR 2.67, 95% CI 1.71-4.16]), moderate malnutrition (aOR 2.41, 95% CI 1.87-3.09), and female sex (aOR 1.82, 95% CI 1.43-2.32). CONCLUSION: Children with a pulse oximetry measurement had a lower CFR. Many children hospitalized with chest-indrawing pneumonia were hypoxemic and one in 10 died. Young age and moderate malnutrition were risk factors for in-hospital chest-indrawing pneumonia-related mortality. Pulse oximetry should be integrated in pneumonia hospital care for children under 5 years.

Nasopharyngeal Viral and Bacterial Co-Detection among Children from Low- and Middle-Income Countries with and without Pneumonia.

The role of microbial coinfection in the pathogenesis of pneumonia in children is not well known. The aim of this work was to describe the prevalence of microorganism co-detection in nasopharyngeal samples (NPS) of pneumonia cases and control subjects and to study the potential association between nasopharyngeal microorganism co-detection and pneumonia. A case-control study was carried out from 2010 to 2014 in nine study sites located in low- or middle-income countries. The data from 888 children under 5 years of age with pneumonia (cases) and 870 children under 5 without pneumonia (controls) were analyzed. Nasopharyngeal samples were collected; reverse transcription polymerase chain reaction (RT-PCR) enabled the detection of five bacteria and 19 viruses. Multiple, mixed-effects logistic regression modeling was undertaken to evaluate the association between microorganism co-detection and pneumonia. A single Streptococcus pneumoniae colonization was observed in 15.2% of the controls and 10.1% of the cases (P = 0.001), whereas S. pneumoniae and a single virus co-detection was observed in 33.3% of the cases and in 14.6% of the controls (P < 0.001). Co-detections with rhinovirus, respiratory syncytial virus, parainfluenza virus, human metapneumovirus, and influenza virus were more frequent in the cases compared with the controls (P < 0.001) and were significantly associated with pneumonia in multiple regression analysis. The proportion of single virus detection without bacterial co-detection was not different between cases and controls (13.6% versus 11.3%, P = 0.13). This study suggests that coinfection of S. pneumoniae and certain viruses may play a role in the pathophysiology of pneumonia in children.

Derivation and validation of a novel risk assessment tool to identify children aged 2-59 months at risk of hospitalised pneumonia-related mortality in 20 countries.

INTRODUCTION: Existing risk assessment tools to identify children at risk of hospitalised pneumonia-related mortality have shown suboptimal discriminatory value during external validation. Our objective was to derive and validate a novel risk assessment tool to identify children aged 2-59 months at risk of hospitalised pneumonia-related mortality across various settings. METHODS: We used primary, baseline, patient-level data from 11 studies, including children evaluated for pneumonia in 20 low-income and middle-income countries. Patients with complete data were included in a logistic regression model to assess the association of candidate variables with the outcome hospitalised pneumonia-related mortality. Adjusted log coefficients were calculated for each candidate variable and assigned weighted points to derive the Pneumonia Research Partnership to Assess WHO Recommendations (PREPARE) risk assessment tool. We used bootstrapped selection with 200 repetitions to internally validate the PREPARE risk assessment tool. RESULTS: A total of 27 388 children were included in the analysis (mean age 14.0 months, pneumonia-related case fatality ratio 3.1%). The PREPARE risk assessment tool included patient age, sex, weight-for-age z-score, body temperature, respiratory rate, unconsciousness or decreased level of consciousness, convulsions, cyanosis and hypoxaemia at baseline. The PREPARE risk assessment tool had good discriminatory value when internally validated (area under the curve 0.83, 95% CI 0.81 to 0.84). CONCLUSIONS: The PREPARE risk assessment tool had good discriminatory ability for identifying children at risk of hospitalised pneumonia-related mortality in a large, geographically diverse dataset. After external validation, this tool may be implemented in various settings to identify children at risk of hospitalised pneumonia-related mortality.

[Endocervical swabbing in women with COVID-19 symptoms from departments of Paraguay]. / Hisopado endocervical en mujeres con síntomas de COVID-19 provenientes de departamentos del Paraguay.

BACKGROUND: COVID-19 is an eminently respiratory transmissible infection of respiratory initiation, the existence of other sources of contagion is discussed. The ACE2 viral receptor has also been detected in the uterus and vagina; Hence, the involvement of the SARS-CoV-2 virus on the genitourinary system and its possible repercussions on pregnancy has been raised. AIM: To determine the presence of SARS-CoV-2 in endocervical samples of women with COVID-19 in the departments of Paraguay. METHODS: Designed as a prospective observational of transverse cohort. Two hundred women were recruited from August 2020 to February 2021, with no more than 48/72 hours of a previous positive nasopharyngeal swab result for SARS-CoV-2 by reverse transcriptase-polymerase chain reaction (rt-RT-PCR) and who agreed to participate in the study. A clinical epidemiological questionnaire was completed. The samples were taken in health services of the MSPYBS (Public Ministry of Health and Social Welfare), homes and shelters in the different departments of Paraguay. Each patient underwent a swab (dacron swabs) or endocervical cytobrush for the detection of SARS-CoV-2 by rt-RT-PCR. RESULTS: Women recruited had a mean age of 46.5 years (95% CI 31,562.5). They reported contagion with SARS-CoV-2: 75.5% in the community, 13.5% at home, 8.5% in the place of work and 1.5% abroad. The clinical manifestations were: 30% flu syndrome, 22.5% fever, 20% cough, 15.5% anosmia, 15.5% digestive disorders, among other symptoms. The swabs or endocervical cytobrush samples subjected to rt-RT-PCR for the detection of SARS-CoV-2 were negative in the 200 study women. DISCUSSION: It should be noted that the vaginal samples were taken within 24-72 hours after obtaining a positive result for SARS-CoV-2 in the nasopharyngeal swab and that 62.5% of the women were hospitalized in respiratory modules. The reason for the negativity of the exams and their significance are discussed. Conclusión: No SARS Cov-2 infection was detected in the endocervical region of 200 women with clinical manifestations of COVID 19 and evaluated within 48/72 hours of a positive nasopharyngeal result for SARS Cov-2. The results in the study population agree with the findings of other studies reported in the literature.

External validation of the RISC, RISC-Malawi, and PERCH clinical prediction rules to identify risk of death in children hospitalized with pneumonia.

BACKGROUND: Existing scores to identify children at risk of hospitalized pneumonia-related mortality lack broad external validation. Our objective was to externally validate three such risk scores. METHODS: We applied the Respiratory Index of Severity in Children (RISC) for HIV-negative children, the RISC-Malawi, and the Pneumonia Etiology Research for Child Health (PERCH) scores to hospitalized children in the Pneumonia REsearch Partnerships to Assess WHO REcommendations (PREPARE) data set. The PREPARE data set includes pooled data from 41 studies on pediatric pneumonia from across the world. We calculated test characteristics and the area under the curve (AUC) for each of these clinical prediction rules. RESULTS: The RISC score for HIV-negative children was applied to 3574 children 0-24 months and demonstrated poor discriminatory ability (AUC = 0.66, 95% confidence interval (CI) = 0.58-0.73) in the identification of children at risk of hospitalized pneumonia-related mortality. The RISC-Malawi score had fair discriminatory value (AUC = 0.75, 95% CI = 0.74-0.77) among 17 864 children 2-59 months. The PERCH score was applied to 732 children 1-59 months and also demonstrated poor discriminatory value (AUC = 0.55, 95% CI = 0.37-0.73). CONCLUSIONS: In a large external application of the RISC, RISC-Malawi, and PERCH scores, a substantial number of children were misclassified for their risk of hospitalized pneumonia-related mortality. Although pneumonia risk scores have performed well among the cohorts in which they were derived, their performance diminished when externally applied. A generalizable risk assessment tool with higher sensitivity and specificity to identify children at risk of hospitalized pneumonia-related mortality may be needed. Such a generalizable risk assessment tool would need context-specific validation prior to implementation in that setting.

Predominance of rotavirus G2P[4] and emergence of G12P[9] strains in Asunción, Paraguay, 2006-2007.

Rotavirus is the most common cause of severe diarrhea in children worldwide. Monitoring the diversity of rotavirus strains is of great importance for current and future vaccination programs. To determine the diversity of rotavirus circulating in Asuncion, Paraguay, between 2006 and 2007, we carried out a molecular characterization of rotaviruses detected in children <5 years old and adults (>18 years old). We found that the most common circulating strain was G2P[4] (69/143), followed by G9P[8] (37/143). The temporal distribution of strains showed that, in children, G2P[4] was predominant in 2006, and that G2P[4] and G9P[8] were co-predominant in 2007, whereas in adults, G2P[4] was predominant in both years. Additionally, one G9P[6] and three G12P[9] strains were found in adult samples, making this the first report of these strains circulating in Paraguay. Sequence analysis of the G12P[9] strains suggests across-border migration of this strain within the southern cone of America.

Association of baseline white blood cell counts with tuberculosis treatment outcome: a prospective multicentered cohort study.

OBJECTIVES: Tuberculosis (TB) is the leading infectious cause of death in the world. Cheaper and more accessible TB treatment monitoring methods are needed. Here, we evaluated white blood cell (WBC) absolute counts, lymphocyte, and monocyte proportions during TB treatment, and characterized their association with treatment failure. METHODS: This multicentered prospective cohort study was based in Bangladesh, Georgia, Lebanon, Madagascar, and Paraguay. Adult, non-immunocompromised patients with culture-confirmed pulmonary TB were included and followed up after two months of treatment and at the end of therapy. Blood counts were compared to treatment outcome using descriptive statistics, logistic regression, and Receiver Operating Characteristic (ROC) analyses. RESULTS: Between December 2017 and August 2020, 198 participants were enrolled, and 152 completed treatment, including 28 (18.5%) drug-resistant patients. The rate of cure at the end of treatment was 90.8% (138/152). WBC absolute counts decreased, and lymphocyte proportions increased throughout treatment. In multivariate analyses, baseline high WBC counts and low lymphocyte proportions were associated with positive sputum culture results at the end of treatment (WBC > 11,450 cells/mm3: p = 0.048; lymphocytes <16.0%: p = 0.039; WBC > 11,450 cells/mm3 and lymphocytes <16.0%: p = 0.024). CONCLUSION: High WBC counts and low lymphocyte proportions at baseline are significantly associated with the risk of TB treatment failure.

Relevance of QuantiFERON-TB Gold Plus and Heparin-Binding Hemagglutinin Interferon-γ Release Assays for Monitoring of Pulmonary Tuberculosis Clearance: A Multicentered Study.

Background: Tuberculosis (TB) is a leading infectious cause of death. To improve treatment efficacy, quicker monitoring methods are needed. The objective of this study was to monitor the response to a heparin-binding hemagglutinin (HBHA) interferon-γ (IFN-γ) release assay (IGRA) and QuantiFERON-TB Gold Plus (QFT-P) and to analyze plasma IFN-γ levels according to sputum culture conversion and immune cell counts during treatment. Methods: This multicentered cohort study was based in Bangladesh, Georgia, Lebanon, Madagascar, and Paraguay. Adult, non-immunocompromised patients with culture-confirmed pulmonary TB were included. Patients were followed up at baseline (T0), after two months of treatment (T1), and at the end of therapy (T2). Clinical data and blood samples were collected at each timepoint. Whole blood samples were stimulated with QFT-P antigens or recombinant methylated Mycobacterium tuberculosis HBHA (produced in Mycobacterium smegmatis; rmsHBHA). Plasma IFN-γ levels were then assessed by ELISA. Findings: Between December 2017 and September 2020, 132 participants completed treatment, including 28 (21.2%) drug-resistant patients. rmsHBHA IFN-γ increased significantly throughout treatment (0.086 IU/ml at T0 vs. 1.03 IU/ml at T2, p < 0.001) while QFT-P IFN-γ remained constant (TB1: 0.53 IU/ml at T0 vs. 0.63 IU/ml at T2, p = 0.13). Patients with low lymphocyte percentages (<14%) or high neutrophil percentages (>79%) at baseline had significantly lower IFN-γ responses to QFT-P and rmsHBHA at T0 and T1. In a small group of slow converters (patients with positive cultures at T1; n = 16), we observed a consistent clinical pattern at baseline (high neutrophil percentages, low lymphocyte percentages and BMI, low TB1, TB2, and MIT IFN-γ responses) and low rmsHBHA IFN-γ at T1 and T2. However, the accuracy of the QFT-P and rmsHBHA IGRAs compared to culture throughout treatment was low (40 and 65% respectively). Combining both tests improved their sensitivity and accuracy (70-80%) but not their specificity (<30%). Conclusion: We showed that QFT-P and rmsHBHA IFN-γ responses were associated with rates of sputum culture conversion. Our results support a growing body of evidence suggesting that rmsHBHA IFN-γ discriminates between the different stages of TB, from active disease to controlled infection. However, further work is needed to confirm the specificity of QFT-P and rmsHBHA IGRAs for treatment monitoring.

IL-17A, a possible biomarker for the evaluation of treatment response in Trypanosoma cruzi infected children: A 12-months follow-up study in Bolivia.

BACKGROUND: The National Program for Chagas disease was implemented in Bolivia in 2006, and it greatly decreased the number of infections through vector control. Subsequently, a treatment regimen of benznidazole (BNZ) was started in seropositive school-age children living in certified vector control areas. METHODS AND FINDINGS: We conducted a 12-month follow-up study and seven blood samples were taken during and after the treatment. Serology, conventional diagnostic PCR (cPCR) and quantitative Real-time PCR (qPCR) were performed. Plasma Th1/Th2/Th17 cytokines levels were also determined. Approximately 73 of 103 seropositive children complied with BNZ, with three interruptions due to side effects. To evaluate each individual's treatment efficacy, the cPCR and qPCR values during the final 6 months of the follow-up period were observed. Among 57 children who completed follow-up, 6 individuals (11%) showed both cPCR(+) and qPCR(+) (non reactive), 24 (42%) cPCR(-) but qPCR(+) (ambiguous) and 27 (47%) cPCR(-) and qPCR(-) (reactive). Within 14 Th1/Th2/Th17 cytokines, IL-17A showed significantly higher levels in seropositive children before the treatment compared to age-matched seronegative children and significantly decreased to the normal level one-year after. Moreover, throughout the follow-up study, IL-17A levels were positively co-related to parasite counts detected by qPCR. At the 12 months' time point, IL-17A levels of non-reactive subjects were significantly higher than either those of reactive or ambiguous subjects suggesting that IL-17A might be useful to determine the reactivity to BNZ treatment. CONCLUSIONS: Plasma levels of IL-17A might be a bio-marker for detecting persistent infection of T. cruzi and its chronic inflammation.