Skin and Soft Tissue Infection in People Living With Human Immunodeficiency Virus in a Large, Urban, Public Healthcare System in Houston, Texas, 2009-2014

Race, ethnicity, and risk for colonization and infection with key bacterial pathogens: a scoping review

Background

Racial and ethnic disparities in infectious disease burden have been reported in the USA and globally, most recently for COVID-19. It remains unclear whether such disparities also exist for priority bacterial pathogens that are increasingly antimicrobial-resistant. We conducted a scoping review to summarize published studies that report on colonization or community-acquired infection with pathogens among different races and ethnicities.

Methods

We conducted an electronic literature search of MEDLINE®, Daily, Global Health, Embase, Cochrane Central, and Web of Science from inception to January 2022 for eligible observational studies. Abstracts and full-text publications were screened in duplicate for studies that reported data for race or ethnicity for at least one of the pathogens of interest.

Results

Fifty-four observational studies in 59 publications met our inclusion criteria. Studies reported results for Staphylococcus aureus (n=56), Escherichia coli (n=8), Pseudomonas aeruginosa (n=2), Enterobacterales (n=1), Enterococcus faecium (n=1), and Klebsiella pneumoniae (n=1), and were conducted in the USA (n=42), Israel (n=5), New Zealand (n=4), Australia (n=2), and Brazil (n=1). USA studies most often examined Black and Hispanic minority groups and regularly reported a higher risk of these pathogens in Black persons and mixed results for Hispanic persons. Ethnic minority groups were often reported to be at a higher risk in other countries.

Conclusion

Sufficient evidence was identified to justify systematic reviews and meta-analyses evaluating the relationship between race, ethnicity, and community-acquired S. aureus and E. coli, although data were rare for other pathogens. We recommend that future studies clarify whether race and ethnicity data are self-reported, collect race and ethnicity data in conjunction with the social determinants of health, and make a concerted effort to include non-English speakers and Indigenous populations from the Americas, when possible.

Community-acquired Staphylococcus aureus skin and soft tissue infection risk assessment using hotspot analysis and risk maps: the case of California emergency departments

BACKGROUND

Community-acquired Staphylococcus aureus (CA-Sa) skin and soft tissue infections (SSTIs) are historically associated with densely populated urban areas experiencing high poverty rates, intravenous drug use, and homelessness. However, the epidemiology of CA-Sa SSTIs in the United States has been poorly understood since the plateau of the Community-acquired Methicillin-resistant Staphylococcus aureus epidemic in 2010. This study examines the spatial variation of CA-Sa SSTIs in a large, geographically heterogeneous population and identifies neighborhood characteristics associated with increased infection risk.

METHODS

Using a unique neighborhood boundary, California Medical Service Study Areas, a hotspot analysis, and estimates of neighborhood infection risk ratios were conducted for all CA-Sa SSTIs presented in non-Federal California emergency departments between 2016 and 2019. A Bayesian Poisson regression model evaluated the association between neighborhood-level infection risk and population structure, neighborhood poverty rates, and being a healthcare shortage area.

RESULTS

Emergency departments in more rural and mountainous parts of California experienced a higher burden of CA-Sa SSTIs between 2016 and 2019. Neighborhoods with high infection rates were more likely to have a high percentage of adults living below the federal poverty level and be a designated healthcare shortage area. Measures of population structure were not associated with infection risk in California neighborhoods.

CONCLUSIONS

Our results highlight a potential change in the epidemiology of CA-Sa SSTIs in California emergency departments. Future studies should investigate the CA-Sa burden in other geographies to identify whether this shift in epidemiology holds across other states and populations. Further, a more thorough evaluation of potential mechanisms for the clustering of infections seen across California neighborhoods is needed.

Current and Past Immunodeficiency Are Associated With Higher Hospitalization Rates Among Persons on Virologically Suppressive Antiretroviral Therapy for up to 11 Years

BACKGROUND

Persons with human immunodeficiency virus (PWH) with persistently low CD4 counts despite efficacious antiretroviral therapy could have higher hospitalization risk.

METHODS

In 6 US and Canadian clinical cohorts, PWH with virologic suppression for ≥1 year in 2005-2015 were followed until virologic failure, loss to follow-up, death, or study end. Stratified by early (years 2-5) and long-term (years 6-11) suppression and lowest presuppression CD4 count <200 and ≥200 cells/µL, Poisson regression models estimated hospitalization incidence rate ratios (aIRRs) comparing patients by time-updated CD4 count category, adjusted for cohort, age, gender, calendar year, suppression duration, and lowest presuppression CD4 count.

RESULTS

The 6997 included patients (19 980 person-years) were 81% cisgender men and 40% white. Among patients with lowest presuppression CD4 count <200 cells/μL (44%), patients with current CD4 count 200-350 vs >500 cells/μL had aIRRs of 1.44 during early suppression (95% confidence interval [CI], 1.01-2.06), and 1.67 (95% CI, 1.03-2.72) during long-term suppression. Among patients with lowest presuppression CD4 count ≥200 (56%), patients with current CD4 351-500 vs >500 cells/μL had an aIRR of 1.22 (95% CI, .93-1.60) during early suppression and 2.09 (95% CI, 1.18-3.70) during long-term suppression.

CONCLUSIONS

Virologically suppressed patients with lower CD4 counts experienced higher hospitalization rates and could potentially benefit from targeted clinical management strategies.

Approach to the Patient with a Skin and Soft Tissue Infection

The diagnosis of a skin and soft tissue infection (SSTI) requires careful attention to a patient's history, physical examination, and diagnostic test results. We review for many bacterial, viral, fungal, and parasitic pathogens that cause SSTIs the clues for reaching a diagnosis, including reported past medical history, hobbies and behaviors, travel, insect bites, exposure to other people and to animals, environmental exposures to water, soil, or sand, as well as the anatomic site of skin lesions, their morphology on examination, and their evolution over time. Laboratory and radiographic tests are discussed that may be used to confirm a specific diagnosis.