Predictors of skin and soft tissue infections among sample of rural residents who inject drugs

Infectious Diseases Among People Experiencing Homelessness: A Systematic Review of the Literature in the United States and Canada, 2003-2022

Homelessness increases the risk of acquiring an infectious disease. We conducted a systematic review of the literature to identify quantitative data related to infectious diseases and homelessness. We searched Google Scholar, PubMed, and SCOPUS for quantitative literature published from January 2003 through December 2022 in English from the United States and Canada. We excluded literature on vaccine-preventable diseases and HIV because these diseases were recently reviewed. Of the 250 articles that met inclusion criteria, more than half were on hepatitis C virus or Mycobacterium tuberculosis. Other articles were on COVID-19, respiratory syncytial virus, Staphylococcus aureus, group A Streptococcus, mpox (formerly monkeypox), 5 sexually transmitted infections, and gastrointestinal or vectorborne pathogens. Most studies showed higher prevalence, incidence, or measures of risk for infectious diseases among people experiencing homelessness as compared with people who are housed or the general population. Although having increased published data that quantify the infectious disease risks of homelessness is encouraging, many pathogens that are known to affect people globally who are not housed have not been evaluated in the United States or Canada. Future studies should focus on additional pathogens and factors leading to a disproportionately high incidence and prevalence of infectious diseases among people experiencing homelessness.

Water, sanitation and hygiene insecurity predict abscess incidence among people who inject drugs in a binational US-Mexico metropolitan area: A longitudinal cohort study

INTRODUCTION

People who inject drugs (PWID) are at high risk of developing injection-related infections, including abscesses. Access to water, sanitation, and hygiene (WASH) are key human rights and services; yet these services have been underexplored as predictors of abscesses among PWID.

METHODS

Longitudinal analysis was employed among a cohort of PWID to determine if WASH insecurity (lack of access) was associated with abscess incidence in the Tijuana, Mexico and San Diego, United States metropolitan area during 24-months of follow-up survey data from 2020 to 2023. We calculated abscess prevalence at baseline and tracked the incidence of new abscesses among individuals without an abscess during the previous visit. Time dependent Cox regression modeling was employed with variance clustered by participant to characterize the relationship between WASH insecurity and abscess incidence.

RESULTS

At baseline, hand hygiene insecurity, bathing insecurity in the previous six months and open defecation in the last week, were reported by 60 %, 54 % and 38 % of participants, respectively; 21 % reported an abscess in the last six months. The incidence of abscesses was 24.4 (95 %CI: 21.1-27.6) per 100 person-years. After adjusting for covariates, the hazard of developing an abscess remained significantly elevated among individuals using non-improved (with risk of contamination) water sources (e.g., surface water) for preparing drugs (adjusted HR [adjHR]: 1.49 [95 %CI: 1.01-2.21], experiencing bathing insecurity (adjHR: 1.59 [95 %CI: 1.12-2.24]) and open defecation (adjHR: 1.65 [95 %CI: 1.16-2.35]).

CONCLUSIONS

PWID in the Tijuana-San Diego metropolitan area reported facing high rates of insecurity accessing WASH services. Abscess incidence was higher (four to nine times) than observed rate among PWID cohorts in other settings. Access to continuously available toilet facilities, bathing infrastructure, and safe water sources for preparing drugs for injection could prevent abscesses among PWID. Accessible WASH infrastructure should be ensured among PWID communities and promoted as a key component of harm reduction infrastructure.

The burden of skin and soft tissue, bone and joint infections in an Australian cohort of people who inject drugs

INTRODUCTION

There are currently limited data regarding the clinical and economic significance of skin and soft tissue infections (SSTI) and bone and joint infections in Australian people who inject drugs (PWID).

METHODS

Retrospective cohort study in adult PWID admitted to Monash Health, a large heath care network with six hospitals in Victoria, Australia. Inpatients were identified using administrative datasets and International Classification of Disease (ICD-10) coding for specific infection-related conditions. Cost analysis was based on mean ward, intensive care and hospital-in-the-home (HITH) lengths of stay. Spinal infections and endocarditis were excluded as part of previous studies.

RESULTS

A total of 185 PWID (61 female, 124 male, median age 37) meeting the study criteria were admitted to Monash Health between January 2010 and January 2021. Admitting diagnoses included 78 skin abscesses, 80 cellulitis, 17 septic arthritis, 4 osteomyelitis, 3 thrombophlebitis and 1 each of necrotising fasciitis, vasculitis and myositis. Pain (87.5%) and swelling (75.1%) were the most common presenting complaints. Opioids (67.4%) and methamphetamine (37.5%) were the most common primary drugs injected. Almost half (46.5%) of patients had concurrent active hepatitis C (HCV) infection on admission. Hepatitis B (HBV) and Human Immunodeficiency Virus (HIV) were uncommon. The most significant causative organism was methicillin-susceptible Staphylococcus aureus (24.9%). In 40.0% (74/185) no organism was identified. Patients required a median acute hospital stay of 5 days (2-51 days). There were 15 patients admitted to the intensive care unit (ICU) with median duration 2 days. PICC line insertion for antibiotics was required in 16.8% of patients, while 51.4% required surgical intervention. Median duration of both oral and IV antibiotic therapy was 11 days. Almost half (48.6%) of patients were enrolled in an opioid maintenance program on discharge. Average estimated expenditure was AUD $16, 528 per admission.

CONCLUSION

Skin and soft tissue and joint infections are a major cause of morbidity for PWID. Admission to hospital provides opportunistic involvement of addiction specialty services.

Endocarditis, drug use and biological sex: A statewide analysis comparing sex differences in drug use-associated infective endocarditis with other drug-related harms

OBJECTIVES

Hospitalizations for drug use-associated infective endocarditis (DUA-IE) have risen sharply across the United States over the past decade. The sex composition of DUA-IE remains less clear, and studies have indicated a possible shift to more females. We aimed to compare more recent statewide hospitalization rates for DUA-IE in females versus males and contextualize them among other drug-related harms in North Carolina (NC).

METHODS

This study was a retrospective analysis using public health datasets of all NC hospital discharges for infective endocarditis from 2016 to 2020. Drug use-related hospitalizations were identified using ICD-10-CM codes. Discharge rates by year and sex for DUA-IE and non-DUA-IE were calculated and compared to fatal overdoses and acute hepatitis C (HCV). Temporal, demographic, and pregnancy trends were also assessed.

RESULTS

Hospitalizations rates for DUA-IE were 9.7 per 100,000 over the five-year period, and 1.2 times higher among females than males. Females composed 57% of DUA-IE hospitalizations over the period. Conversely, fatal overdose, acute HCV, and non-DUA-IE hospitalization rates were higher among males. Age, county of residence, and pregnancy status did not explain the higher DUA-IE among females.

CONCLUSION

Females now comprise the majority of DUA-IE hospitalizations in NC, unlike other drug-related harms. No clear demographic or geographic associations were found, and further research is needed to explain this phenomenon. Preventing invasive infections among females who inject drugs should be prioritized.

A multicomponent holistic care pathway for people who use drugs in Tayside, Scotland

BACKGROUND

People Who Use Drugs (PWUD) are at high risk of non-fatal overdose and other drug-related harms. The United Kingdom drugs policy landscape makes it challenging to support those at risk. Tayside, in East Scotland, has a sizeable population at risk of drug-related harms. In 2021, the National Health Service implemented a care pathway for PWUD to provide multidimensional healthcare interventions. We aimed to quantify drug-related harms; assess wider health and well-being; and understand substance use trends and behaviours, among those engaged in the pathway.

METHODS

Existing community-embedded blood-borne virus pathways were adapted to provide multiple healthcare assessments over three visits. We undertook an observational cohort study to analyse uptake and outcomes for the initial cohort of PWUD engaged at appointment one.

RESULTS

From August 2021-September 2022, 150 PWUD engaged with the pathway. Median age was 39 (34-42) years, 108 (72%) were male, and 124 (83%) lived in deprived areas. Seventy (47%) had been disengaged from healthcare for over a year. Polysubstance use was reported by 124 (83%), 42 (28%) disclosed injecting daily, and 54 (36%) shared equipment. Fifty-four (36%) experienced recent non-fatal overdose, and there were six overdose fatalities (4.1 [1.5-9.0] per 100PY). The offer of take-home naloxone was accepted by 108 (72%). Fourteen (9%) were diagnosed with Hepatitis C and two (1%) with HIV. Renal, hepatological, and endocrine impairment were observed among 30 (20%), 23 (15%), and 11 (7%), people respectively. Ninety-six (65%) had high risk of clinical depression. Forty-eight (32%) declined Covid-19 vaccination.

CONCLUSION

The pathway engaged PWUD with high exposure to recent non-fatal overdose and other drug-related harms, alongside co-morbid health issues. Our results suggest multi-dimensional health assessments coupled with harm reduction in community settings, with appropriate linkage to care, are warranted for PWUD. Service commissioners should seek to integrate these assessments where possible.

Community-acquired skin and soft-tissue infections in people who inject drugs

PURPOSE OF REVIEW

The aim of this review is to discuss the latest evidence of the epidemiology, microbiology, risk factors, diagnosis and management of community-acquired skin and soft tissue infections (SSTIs) in people who inject drug (PWID).

RECENT FINDINGS

SSTIs are common complications in PWID and a major cause of morbidity and mortality. Infections can range from uncomplicated cellulitis, to abscesses, deep tissue necrosis and necrotizing fasciitis. They are predominantly caused by Gram-positive pathogens in particular Staphylococcus aureus and Streptococcus species; however, toxin-producing organisms such as Clostridium botulism or Clostridium tetani should be considered. The pathogenesis of SSTI in the setting of intravenous drug use (IDU) is different from non-IDU related SSTI, and management often requires surgical interventions in addition to adjunctive antibiotics. Harm reduction strategies and education about safe practices should be implemented to prevent morbidity and mortality as well as healthcare burden of SSTI in PWID.

SUMMARY

Prompt diagnosis and proper medical and surgical management of SSTI will improve outcomes in PWID.

Prevalence and factors associated with hospitalisation for bacterial skin infections among people who inject drugs: The ETHOS Engage Study

BACKGROUND

Injecting-related skin and soft tissue infections (SSTIs) are a preventable cause of inpatient hospitalisation among people who inject drugs (PWID). This study aimed to determine the prevalence of hospitalisation for SSTIs among PWID, and identify similarities and differences in factors associated with hospitalisation for SSTIs versus non-bacterial harms related to injecting drug use.

METHODS

We performed cross-sectional analyses of baseline data from an observational cohort study of PWID attending drug treatment clinics and needle and syringe programs in Australia. Logistic regression models were used to identify factors associated with self-reported hospitalisation for (1) SSTIs (abscess and/or cellulitis), and (2) non-bacterial harms related to injecting drug use (e.g., non-fatal overdose; hereafter referred to as non-bacterial harms), both together and separately.

RESULTS

1851 participants who injected drugs in the previous six months were enrolled (67% male; 85% injected in the past month; 42% receiving opioid agonist treatment [OAT]). In the previous year, 40% (n = 737) had been hospitalised for drug-related causes: 20% (n = 377) and 29% (n = 528) of participants were admitted to hospital for an SSTI and non-bacterial harm, respectively. Participants who were female (adjusted odds ratio [aOR]: 1.53, 95% CI: 1.19-1.97) or homeless (aOR: 1.59, 95% CI: 1.16-2.19) were more likely to be hospitalised for an SSTI, but not a non-bacterial harm. Both types of hospitalisation were more likely among people recently released from prison.

CONCLUSIONS

Hospitalisation for SSTIs is common among PWID. Community-based interventions to prevent SSTIs and subsequent hospitalisation among PWID will require targeting of at-risk groups, including women, people experiencing homelessness, and incarcerated people upon prison release.

Identifying predictors of varices grading in patients with cirrhosis using ensemble learning

Objectives

The present study was conducted to improve the performance of predictive methods by introducing the most important factors which have the highest effects on the prediction of esophageal varices (EV) grades among patients with cirrhosis.

Methods

In the present study, the ensemble learning methods, including Catboost and XGB classifier, were used to choose the most potent predictors of EV grades solely based on routine laboratory and clinical data, a dataset of 490 patients with cirrhosis gathered. To increase the validity of the results, a five-fold cross-validation method was applied. The model was conducted using python language, Anaconda open-source platform. TRIPOD checklist for prediction model development was completed.

Results

The Catboost model predicted all the targets correctly with 100% precision. However, the XGB classifier had the best performance for predicting grades 0 and 1, and totally the accuracy was 91.02%. The most significant variables, according to the best performing model, which was CatBoost, were child score, white blood cell (WBC), vitalism K (K), and international normalized ratio (INR).

Conclusions

Using machine learning models, especially ensemble learning models, can remarkably increase the prediction performance. The models allow practitioners to predict EV risk at any clinical visit and decrease unneeded esophagogastroduodenoscopy (EGD) and consequently reduce morbidity, mortality, and cost of the long-term follow-ups for patients with cirrhosis.