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Background Following migration from Schistosoma and Strongyloides endemic to non-endemic regions, people remain at high risk for adverse sequelae from these chronic infections. HIV co-infected persons are particularly vulnerable to the serious and potentially fatal consequences of untreated helminth infection. While general screening guidelines exist for parasitic infection screening in immigrant populations, they remain silent on HIV positive populations. This study assessed the seroprevalence, epidemiology and laboratory characteristics of these two parasitic infections in a non-endemic setting in an immigrant/refugee HIV positive community. Methods Between February 2015 and 2018 individuals born outside of Canada receiving care at the centralized HIV clinic serving southern Alberta, Canada were screened by serology and direct stool analysis for schistosomiasis and strongyloidiasis. Canadian born persons with travel-based exposure risk factors were also screened. Epidemiologic and laboratory values were analyzed using bivariate logistic regression. We assessed the screening utility of serology, direct stool analysis, eosinophilia and hematuria. Results 253 HIV positive participants were screened. The prevalence of positive serology for Schistosoma and Strongyloides was 19.9 and 4.4%, respectively. Age between 40 and 50 years (OR 2.50, 95% CI 1.13–5.50), refugee status (3.55, 1.72–7.33), country of origin within Africa (6.15, 2.44–18.60), eosinophilia (3.56, 1.25–10.16) and CD4 count 3 (2.46, 1.02–5.92) were associated with positive Schistosoma serology. Eosinophilia (11.31, 2.03–58.94) was associated with positive Strongyloides serology. No Schistosoma or Strongyloides parasites were identified by direct stool microscopy. Eosinophilia had poor sensitivity for identification of positive serology. Hematuria was not associated with positive Schistosoma serology. Conclusion Positive Schistosoma and Strongyloides serology was common in this migrant HIV positive population receiving HIV care in Southern Alberta. This supports the value of routine parasitic screening as part of standard HIV care in non-endemic areas. Given the high morbidity and mortality in this relatively immunosuppressed population, especially for Strongyloides infection, screening should include both serologic and direct parasitological tests. Eosinophilia and hematuria should not be used for Schistosoma and Strongyloides serologic screening in HIV positive migrants in non-endemic settings.

Background Lack of a gold standard for identifying bacterial and viral etiologies of pneumonia has limited evaluation of C-reactive protein (CRP) for identifying bacterial pneumonia. We evaluated the sensitivity and specificity of CRP for identifying bacterial vs respiratory syncytial virus (RSV) pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) multicenter case-control study. Methods We measured serum CRP levels in cases with World Health Organization–defined severe or very severe pneumonia and a subset of community controls. We evaluated the sensitivity and specificity of elevated CRP for “confirmed” bacterial pneumonia (positive blood culture or positive lung aspirate or pleural fluid culture or polymerase chain reaction [PCR]) compared to “RSV pneumonia” (nasopharyngeal/oropharyngeal or induced sputum PCR-positive without confirmed/suspected bacterial pneumonia). Receiver operating characteristic (ROC) curves were constructed to assess the performance of elevated CRP in distinguishing these cases. Results Among 601 human immunodeficiency virus (HIV)–negative tested controls, 3% had CRP ≥40 mg/L. Among 119 HIV-negative cases with confirmed bacterial pneumonia, 77% had CRP ≥40 mg/L compared with 17% of 556 RSV pneumonia cases. The ROC analysis produced an area under the curve of 0.87, indicating very good discrimination; a cut-point of 37.1 mg/L best discriminated confirmed bacterial pneumonia (sensitivity 77%) from RSV pneumonia (specificity 82%). CRP ≥100 mg/L substantially improved specificity over CRP ≥40 mg/L, though at a loss to sensitivity. Conclusions Elevated CRP was positively associated with confirmed bacterial pneumonia and negatively associated with RSV pneumonia in PERCH. CRP may be useful for distinguishing bacterial from RSV-associated pneumonia, although its role in discriminating against other respiratory viral-associated pneumonia needs further study.

Background.Sputum microscopy and culture are commonly used for diagnosing the cause of pneumonia in adults but are rarely performed in children due to difficulties in obtaining specimens. Induced sputum is occasionally used to investigate lower respiratory infections in children but has not been widely used in pneumonia etiology studies. Methods.We evaluated the diagnostic utility of induced sputum microscopy and culture in patients enrolled in the Pneumonia Etiology Research for Child Health (PERCH) study, a large study of community-acquired pneumonia in children aged 1–59 months. Comparisons were made between induced sputum samples from hospitalized children with radiographically confirmed pneumonia and children categorized as nonpneumonia (due to the absence of prespecified clinical and laboratory signs and absence of infiltrate on chest radiograph). Results.One induced sputum sample was available for analysis from 3772 (89.1%) of 4232 suspected pneumonia cases enrolled in PERCH. Of these, sputum from 2608 (69.1%) met the quality criterion of Conclusions.The findings of this study do not support the culture of induced sputum specimens as a diagnostic tool for pneumonia in young children as part of routine clinical practice.

Background Antibiotic exposure and specimen volume are known to affect pathogen detection by culture. Here we assess their effects on bacterial pathogen detection by both culture and polymerase chain reaction (PCR) in children. Methods PERCH (Pneumonia Etiology Research for Child Health) is a case-control study of pneumonia in children aged 1–59 months investigating pathogens in blood, nasopharyngeal/oropharyngeal (NP/OP) swabs, and induced sputum by culture and PCR. Antibiotic exposure was ascertained by serum bioassay, and for cases, by a record of antibiotic treatment prior to specimen collection. Inoculated blood culture bottles were weighed to estimate volume. Results Antibiotic exposure ranged by specimen type from 43.5% to 81.7% in 4223 cases and was detected in 2.3% of 4863 controls. Antibiotics were associated with a 45% reduction in blood culture yield and approximately 20% reduction in yield from induced sputum culture. Reduction in yield of Streptococcus pneumoniae from NP culture was approximately 30% in cases and approximately 32% in controls. Several bacteria had significant but marginal reductions (by 5%–7%) in detection by PCR in NP/ OP swabs from both cases and controls, with the exception of S. pneumoniae in exposed controls, which was detected 25% less frequently compared to nonexposed controls. Bacterial detection in induced sputum by PCR decreased 7% for exposed compared to nonexposed cases. For every additional 1 mL of blood culture specimen collected, microbial yield increased 0.51% (95% confidence interval, 0.47%–0.54%), from 2% when volume was ≤1 mL to approximately 6% for ≥3 mL. Conclusions Antibiotic exposure and blood culture volume affect detection of bacterial pathogens in children with pneumonia and should be accounted for in studies of etiology and in clinical management.

The Glasgow Coma Scale (GCS) only assesses orientation after traumatic brain injury (TBI). ‘Post-traumatic amnesia’ (PTA) comprises orientation, anterograde amnesia (AA) and retrograde amnesia (RA). However, RA is often disregarded in formalized PTA assessment. Drugs can potentially confound PTA assessment: e.g. midazolam can cause AA. However, potential drug confounders are also often disregarded in formalized PTA testing. One study of medium-stay elective-surgery orthopaedic patients (without TBI) demonstrated AA in 80% taking opiates after general anesthesia. However, RA was not assessed. Opiates/opioids are frequently administered after TBI. We compared AA and RA in short-stay orthopaedic surgery in-patients (without TBI) taking post-operative opioids after opiate/opioid/benzodiazepine-free spinal anesthesia. In a prospective cohort, the Westmead PTA Scale (WPTAS) was used to assess AA (WPTAS < 12), whilst RA was assessed using the Galveston Orientation and Amnesia Test RA item. Results were obtained in n = 25 (60 ± 14 yrs, M:F 17:8). Surgery was uncomplicated: all were discharged by Day-4. All were taking regular oxycodone as a new post-operative prescription. Only one co-administered non-opioid was potentially confounding (temezepam, n = 4). Of 25, 14 (56%) demonstrated AA: five (20%) were simultaneously disorientated. Mean WPTAS was 11.08 ± 1.22. RA occurred in 0%. Conclusions: AA and disorientation, but not RA, were associated with in-patients (without TBI) taking opioids. Caution should therefore be applied in assessing AA/orientation in TBI in-patients taking opioids. By contrast, retrograde memory was robust and more reliable: even in older patients with iatrogenic AA and disorientation. RA assessment should therefore be integral to assessing TBI severity in all formalized PTA and GCS testing.