Community-acquired methicillin-resistant Staphylococcus aureus in surgically treated hand infections

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.

Repeat Irrigation and Debridement of Upper Extremity Infections: Do Repeat Cultures Change Antibiotic Treatment Regimens?

BACKGROUND

Organism identification and their antibiotic sensitivity profile are critical for the successful treatment of upper extremity infections. Although many infections resolve with antibiotics alone, some require 1 or more surgical procedures in which culture data are obtained. The purpose of this study was to determine whether repeat cultures taken at subsequent irrigation and debridement of upper extremity infections changed antibiotic treatment.

METHODS

A retrospective review was performed using International Classification of Diseases, Ninth Revision codes to identify all adult patients with an upper extremity infection treated with 2 irrigation and debridement procedures with 2 separate culture data sets over a period of 5 years. Culture organisms and antibiotic sensitivity profiles were compared from each procedure, and changes in antibiotic treatment based on repeat culture information were identified.

RESULTS

In all, 183 patients who underwent 2 irrigation and debridement procedures with repeat culture data were identified. Organisms identified with repeat culture were the same or there was no growth in 153 patients and were different in 30 patients. The antibiotic treatment did not require a change in 170 (92.9%) of 183 patients. Of the 30 patients with different repeat cultures, antibiotic treatment changed in only 13 patients (43.3%). Patients who had a change in antibiotic treatment were more likely to have hepatitis C (P = .005).

CONCLUSIONS

Repeat culture data changed antibiotic treatment in only 7.1% of patients from our cohort. Patients with hepatitis C were more likely to require a change in antibiotic management after obtaining repeat cultures.

Epidemiologic and clinical characteristics of infective endocarditis: a single-center retrospective study in the Bronx, New York

OBJECTIVE

There is paucity of data on the epidemiological, microbiological, and clinical characteristics of patients admitted with infective endocarditis (IE) in the Bronx, New York.

PATIENT AND METHODS

We conducted a retrospective study at Jacobi Medical Center, a tertiary care hospital in the Bronx. All adult patients who were hospitalized with a primary diagnosis of new-onset IE between January 1st, 2010 and September 30th, 2020 were included. The primary outcome was in-hospital mortality. A logistic regression model was used to identify baseline variables associated with in-hospital mortality.

RESULTS

182 patients were included in this analysis (female sex: 38.5%, median age: 54 years). 46 patients (25.3%) reported intravenous drug use. 153 patients (84.1%) had positive blood cultures. Staphylococcus aureus (S. aureus) was the most common isolated pathogen (45.1% of monomicrobial IE). Nearly half of the cases secondary to S. aureus were methicillin resistant Staphylococcus aureus (MRSA) (34/69). 164 patients (90.1%) were diagnosed with native valve IE. The mitral valve was involved in 32.4% of patients followed by the aortic valve (19.8%). The in-hospital mortality was 18.1%. The mortality was higher in the cohort 2010-2015 compared to the cohort 2016-2020 (22.1% vs 14.6%). Increasing age, MRSA IE, and active malignancy were the only variables found to have significant association with in-hospital death.

CONCLUSION

S. aureus was the most common causative agent and MRSA accounted for about half of the S. aureus IE cases. The incidence of IE in patients with intravenous drug use increased over time, while the median age decreased. The in-hospital death rate was higher in 2010-2015 compared to 2016-2020.

Surgical Care of Patients Experiencing Homelessness: A Scoping Review Using a Phases of Care Conceptual Framework

Homelessness is a growing concern across the world, particularly as individuals experiencing homelessness age and face an increasing burden of chronic health conditions. Although substantial research has focused on the medical and psychiatric care of patients experiencing homelessness, literature about the surgical care of these patients is sparse. Our objective was to review the literature to identify areas of concern unique to patients experiencing homelessness with surgical disease. A scoping review was conducted using a comprehensive database for studies from 1990 to September 1, 2020. Studies that included patients who were unhoused and discussed surgical care were included. The inclusion criteria were designed to identify evidence that directly affected surgical care, systems management, and policy making. Findings were organized within a Phases of Surgical Care framework: preoperative care, intraoperative care, postoperative care, and global use. Our search strategy yielded 553 unique studies, of which 23 met inclusion criteria. Most studies were performed at public and/or safety-net hospitals or via administrative datasets, and surgical specialties that were represented included orthopedic, cardiac, plastic surgery trauma, and vascular surgery. Using the Surgical Phases of Care framework, we identified studies that described the impact of housing status in pre- and postoperative phases as well as global use. There was limited identification of barriers to surgical and anesthetic best practices in the intraoperative phase. More than half of studies (52.2%) lacked a clear definition of homelessness. Thus, there is a marked gap in the surgical literature regarding the impact of housing status on optimal surgical care, with the largest area for improvement in the intraoperative phase of surgical and anesthetic decision making. Consistent use of clear definitions of homelessness is lacking. To promote improved care, a standardized approach to recording housing status is needed, and studies must explore vulnerabilities in surgical care unique to this population.

A Nationwide Epidemiological Analysis of Finger Infections Presenting to Emergency Departments in the United States From 2012 to 2016

Background: There is a paucity of literature exploring the epidemiology of finger infections presenting to emergency departments (EDs) on a national scale. The purpose of this study was to determine the national incidence of and risk factors for finger infections. Methods: Finger infections presenting to EDs between 2012 and 2016 were identified in the National Electronic Injury Surveillance System database. Finger infections were characterized by mechanism and type, with subanalyses for sex, race, and age. Results: Over this 5-year period, finger infections accounted for 80 519 visits to EDs in the United States. The annual incidence increased significantly from 4.4 per 100 000 person-years in 2012 to 6.2 in 2016. The 3 most common causes of finger infections were nail manicuring tools, knives, and doors. The most common diagnosis was finger cellulitis (46.3%). Significantly more men developed finger infections than women (relative risk of 1.4). The highest overall incidence was observed in 40- to 59-year-old men (7.8 per 100 000 person-years). Tenosynovitis resulted in the largest proportion of admissions (25%). Conclusions: We have demonstrated a rising incidence of finger infections presenting to EDs, with 40- to 59-year-old patients most at risk. The most common mechanism was the use of nail manicuring tools, such as nail clippers. Patient education may decrease finger infection incidence from these activities, and early detection of finger infections may be crucial to minimizing hospital admissions and invasive treatments.

Optimizing Treatment of Hand Infections: Is MRSA Coverage Always Necessary?

Multiple publications have highlighted the prevalence of methicillin resistant Staphylococcus aureus (MRSA) as a cause of hand infections. We hypothesized that these publications have shifted the empiric treatment of hand infections. The aim of this study was to identify the current standard of care, the most common causative bacteria, and factors leading to extended length of stay for hand infection patients at a suburban hospital to improve treatment and establish an optimized care protocol.

Methods

Retrospective cohort analysis was conducted to identify all patients admitted for hand infections over an 8-year period. A comprehensive chart review of each patient's hospital course was completed.

Results

A total of 70 patients were included. Maximum white blood cell count ≥ 12 was associated with a significantly longer hospital length of stay (9.1 days versus 5.4 days) compared to WBC values < 12 (P < 0.05). Also, 11 out of 23 (47.8%) underwent two or more incision and drainages (I&D's), compared with patients with maximum WBC < 12. Vancomycin use as an empiric antibiotic was widespread (68 patients, 97.1%), despite only 14 (20%) having MRSA positive cultures. Univariate analysis identified a significant increased likelihood for increased length of stay (P < 0.05) and rise in creatinine (P < 0.05) in patients with an initial vancomycin trough level > 20.

Conclusions

This analysis of hand infection treatment in a suburban hospital demonstrates the incidence of MRSA hand infections may not be universally high across institutions. Each hospital should review its own data to optimize hand infection treatment and its associated costs.

Differences in the Predictive value of Elixhauser Comorbidity Index and the Charlson Comorbidity indices in patients with hand infections

PURPOSE

Hand infections are a common source of potentially debilitating morbidity, particularly in patients with comorbid disease. We hypothesize that there is a difference in predictive value between two commonly used comorbidity indices for the prognosis of hand infections, which may have clinical implications in the management of these conditions.

METHODS

The Nationwide Inpatient Sample 2001-2013 database was queried for hand infections using International Classification of Diseases, Ninth Revision codes. The Elixhauser (ECI) and Charlson (CCI) comorbidity scores were calculated based on validated sets of ICD-9 codes. Primary outcomes included mortality, prolonged length of stay (LOS, defined as >95 percentile), discharge destination, and postoperative complications. Indices were compared using receiver operating characteristic (ROC) curves and the areas under the curve (AUC). If confidence intervals overlapped, significance was determined using the DeLong method for correlated ROC curves. This is a validated, non-parametric comparison used for the calculation of the difference between two AUCs.

RESULTS

A weighted total of 1,511,057 patients were included in this study. The majority were Caucasian (57.1%) males (61.4%). Complication rates included 0.9% mortality, 5.3% prolonged length of stay, 25.3% discharges to non-home destinations, and 5.3% post-operative complications. The ECI and CCI each demonstrated good predictive value for mortality, but poor predictive value for non-routine discharge, prolonged LOS, and post-operative complications. There was a significantly increased likelihood of each complication with increasing comorbidity score for both indices, with the greatest odds ratio in the ECI ≥4 cohort.

CONCLUSIONS

The CCI was superior in predicting mortality while the ECI was superior in predicting non-routine discharge, prolonged length of stay, and postoperative complications, but these indices may not be clinically relevant. While both represent good predictive models, a score specifically designed for patients with hand infections may have superior prognostic value.

LEVEL OF EVIDENCE

Level IV.

Antibiotic Management and Antibiotic Resistance in Hand Infections

The rates of methicillin-resistant infections in the hand and upper extremity approach 50% in many facilities. In addition, multidrug resistance is beginning to include clindamycin. This article discusses the history, prevalence, and treatment of both community-acquired and health care-associated methicillin-resistant Staphylococcus aureus in regard to hand infections.

Hand Infections: Epidemiology and Public Health Burden

Upper extremity infections are common. Most infections can be effectively treated with minor surgical procedures and/or oral antibiotics; however, inappropriate or delayed care can result in significant, long-term morbidity. The basic principles of treating hand infections were described more than a century ago and most remain relevant today. Immunosuppressant medications, chronic health conditions such as diabetes and human immunodeficiency virus, and public health problems like intravenous drug use, have changed the landscape of hand infections and provide new challenges in treatment.

Characterizing Hand Infections in an Underserved Population: The Role of Diabetic Status in Antibiotic Choice and Infection Location

Introduction Patients with diabetes mellitus (DM) in underserved communities are at greater risk for hand infections. We aimed to describe the features of hand infections presenting to an urban hospital via laboratories, microbiology, and antibiotic choice with respect to diabetic status. Materials and Methods Patients presenting with any hand infection were reviewed and stratified by DM status and infection location. Labs, culture results, antibiotic regimens, and significant predictors of laboratories or infection location were analyzed. Results Fifty-three patients were included: DM ( n = 24), no-DM ( n = 24), and unknown status ( n = 5). Culture rates were comparable between all groups. Mean erythrocyte sedimentation rate (ESR) was significantly higher in DM (76.19 vs. 51.33); mean white blood cell count (WBC) and C-reactive protein (CRP) were comparable. Diabetics had higher odds of increased ESR (odds ratio [OR] = 1.03). Diabetics received vancomycin/piperacillin/tazobactam (VAN/PTZ) significantly more often (52% vs. 8%). Providers treated DM with VAN/PTZ or any VAN-containing regimen more often than with any other regimen. Proximal infections had significantly higher mean CRP (136.9 vs. 50.5) and WBC (5.19 vs. 3.9) and higher CRP (OR = 1.02). Conclusion This study highlights the need for systematic criteria to better risk- stratify patients for appropriate antibiotic treatment. It may not be appropriate to treat both groups differently, as overly aggressive antibiotic selection may contribute to drug-resistance development.

Evolving Threat of Community Acquired Methicillin Resistant Staphylococcus aureus Upper Extremity Infections in the South Pacific: 2011-2015

Background: Community Acquired Methicillin Resistant Staphylococcus aureus (CA-MRSA) rates have been increasing worldwide and contribute to a growing "global health security threat" as reported by the WHO. Our group previously reported an overall rate of 7% in CA-MRSA upper extremity infections between 2004-2009 at the Auckland Regional Hand Unit. This fell below the Center for Disease Control (CDC) recommendation for empiric antimicrobial cover once local rates exceed 10-15%. We examined prevalence and characteristics of CA-MRSA upper extremity infections in our region over a subsequent 5-year period. Methods: One thousand two hundred and fifty-two patients with upper extremity infections requiring operative management between 2011 and 2015 inclusive were included in this study. Associated clinical characteristics were recorded including ethnicity, cultured organisms, antibiotic sensitivities, infection rate, and treatment practice. Results: One hundred and fifty (12%) of patients had culture positive CA-MRSA upper extremity infections. There was an increasing annual trend. Of note, rates of CA-MRSA in the Maori and Pacific Island ethnic subpopulations exceeded 15% in 2014 and 2015. Susceptibilities, associated factors and patient demographics are reported. Conclusions: Our unit enjoys significantly lower rates of CA-MRSA upper extremity infections than has been reported internationally. However, trends are increasing relative to our prior 6-year report, and the threshold for empiric treatment has been met within the Maori and Pacific Island ethnic subpopulations. This evolving threat is also highlighted by increasing cases of multi-drug resistant CA-MRSA. Evolving regional guidelines for empiric coverage of CA-MRSA among high-risk ethnic subpopulations identified by this study are underway.

MRSA Incidence and Antibiotic Trends in Urban Hand Infections: A 10-Year Longitudinal Study

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is the most reported pathogen in hand infections at urban medical centers throughout the country. Antibiotic sensitivity trends are not well known. The purposes of this study were to examine and determine the drug resistance trends for MRSA infections of the hand and to provide recommendations for empiric antibiotic treatment based on sensitivity profiles. Methods: A 10-year longitudinal, retrospective chart review was performed on all culture-positive hand infections encountered at a single urban medical center from 2005 to 2014. The proportions of all organisms were calculated for each year and collectively. MRSA infections were additionally subanalyzed for antibiotic sensitivity. Results: A total of 815 culture-positive hand infections were identified. Overall, MRSA grew on culture in 46% of cases. A trend toward decreasing annual MRSA incidence was noted over the 10-year study period. There was a steady increase in polymicrobial infections during the same time. Resistance to clindamycin increased steadily during the 10-year study, starting at 4% in 2008 but growing to 31% by 2014. Similarly, levofloxacin resistance consistently increased throughout the study, reaching its peak at 56% in 2014. Conclusions: The annual incidence of MRSA in hand infections has declined overall but remains the most common pathogen. There has been an alternative increase in the number of polymicrobial infections. MRSA resistance to clindamycin and levofloxacin consistently increased during the study period. Empiric antibiotic therapy for hand infections should not only avoid penicillin and other beta-lactams but should also consider avoiding clindamycin and levofloxacin for empiric treatment.

MDCT of hand and wrist infections: emphasis on compartmental anatomy

Hand and wrist infections can present with a spectrum of manifestations ranging from cellulitis to deep-space collections. The various infectious processes can be categorised as superficial or deep infections based on their respective locations relative to the tendons. Superficial hand infections are located superficial to the tendons and are comprised of cellulitis, lymphangitis, paronychia, pulp-space infections, herpetic whitlow, and include volar as well as dorsal subcutaneous abscesses. Deep hand infections are located deep to the tendon sheaths and include synovial space infections, such as infectious tenosynovitis, deep fascial space infections, septic arthritis, necrotising fasciitis, and osteomyelitis. Knowledge of hand and wrist compartmental anatomy is essential for the accurate diagnosis and management of hand infections. Although early and superficial infections of the hand may respond to non-surgical management, most hand infections are surgical emergencies. Multidetector computed tomography (MDCT), with its muliplanar reformation (MPR) and three-dimensional (3D) capabilities, is a powerful tool in the emergency setting for the evaluation of acute hand and wrist pathology. The clinical and imaging features of hand and wrist infections as evident on MDCT will be reviewed with emphasis on contiguous and closed synovial and deep fascial spaces. Knowledge of hand compartmental anatomy enables accurate characterisation of the infectious process and localise the extent of disease in the acute setting.

Methicillin-resistant Staphylococcus aureus infection in the hand

BACKGROUND

Methicillin-resistant Staphylococcus aureus has become an increasingly common cause of skin and soft-issue infections. The purpose of this study was to review and summarize the most recent literature on methicillin-resistant S. aureus infections of the hand.

METHODS

The English-language literature related to methicillin-resistant S. aureus infections of the hand was reviewed, and information related to the history, epidemiology, clinical presentation, and treatment of methicillin-resistant S. aureus infections of the hand was summarized.

RESULTS

Community-acquired methicillin-resistant S. aureus hand infections have increased rapidly in prevalence over the past two decades. The prevalence varies markedly around the world, but in the United States, community-acquired methicillin-resistant S. aureus now causes the majority of purulent hand infections.

CONCLUSIONS

Purulent hand infections should be treated with surgical drainage. When antibiotics are indicated, empiric coverage for community-acquired methicillin-resistant S. aureus should be provided if local prevalence rates exceed 10 to 15 percent.

Hand infections: a retrospective analysis

Purpose. Hand infections are common, usually resulting from an untreated injury. In this retrospective study, we report on hand infection cases needing surgical drainage in order to assess patient demographics, causation of infection, clinical course, and clinical management. Methods. Medical records of patients presenting with hand infections, excluding post-surgical infections, treated with incision and debridement over a one-year period were reviewed. Patient demographics; past medical history; infection site(s) and causation; intervals between onset of infection, hospital admission, surgical intervention and days of hospitalization; gram stains and cultures; choice of antibiotics; complications; and outcomes were reviewed. Results. Most infections were caused by laceration and the most common site of infection was the palm or dorsum of the hand. Mean length of hospitalization was 6 days. Methicillin-resistant Staphylococcus aureus, beta-hemolytic Streptococcus and methicillin-susceptible Staphylococcus aureus were the most commonly cultured microorganisms. Cephalosporins, clindamycin, amoxicillin/clavulanate, penicillin, vancomycin, and trimethoprim/sulfamethoxazole were major antibiotic choices. Amputations and contracture were the primary complications. Conclusions. Surgery along with medical management were key to treatment and most soft tissue infections resolved without further complications. With prompt and appropriate care, most hand infection patients can achieve full resolution of their infection.

Epidemiology of adult acute hand infections at an urban medical center

PURPOSE

To define the current epidemiology of adult acute hand infections in an urban setting, with the aim of helping to improve empiric treatment, as hand infections represent a major source of morbidity and can result in stiffness and, possibly, amputation.

METHODS

We performed an electronic medical record search to identify all patients admitted to our urban academic medical center with diagnoses related to open wounds and infections in the hand and fingers over a 6-year period (2005-2010). We recorded demographic data, location of infection, medical comorbidities, and culture data.

RESULTS

Of the 2,287 patients admitted with diagnoses related to open wounds and infections in the hand and fingers, 1,507 incision and drainage procedures were performed, which resulted in 458 patients (30%) with culture-positive infections. Wound cultures identified 39 different species of bacteria. Most of these were methicillin-resistant Staphylococcus aureus, which compromised 53% of positive cultures, followed by methicillin-sensitive S aureus in 23% of positive cultures. The cultures were polymicrobial in 19%. History of intravenous drug use or diabetes mellitus was a strong predictor of polymicrobial infection.

CONCLUSIONS

Methicillin-resistant Staphylococcus aureus was the most common bacteria cultured from these infections. Empiric antibiotic coverage should routinely cover methicillin-resistant S aureus. We noted a higher incidence of polymicrobial infections than previously reported, particularly with intravenous drug use, diabetes, and human bites. Volar hand infections had the highest percentage of positive cultures, whereas paronychia had the lowest percentage.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Evolving incidence of MRSA in urban hand infections

Methicillin-resistant Staphylococcus aureus (MRSA) is the most commonly cultured bacteria in hand infections. Understanding the most common bacteria involved in hand infections allows appropriate and efficient administration of antibiotics. Delay in treatment may lead to increased morbidity, including stiffness, contracture, and amputation. The purposes of this study are to determine whether the incidence of MRSA in culture-positive hand infections continues to increase and whether MRSA is a risk factor for increased length of stay. Electronic medical records were queried to identify patients admitted to a large, academic urban medical center with the diagnosis of a hand infection between January 1, 2005, and December 31, 2009. Methicillin-resistant S aureus accounted for 220 of the positive cultures over the 5-year study period. Polymicrobial infection represented 81 positive cultures, and MRSA was only present in 10 of these cases. Patients with MRSA were found to have a mean length of hospital stay of 4.1 days compared with 4.5 days in non-MRSA infections. Understanding the most common bacteria involved in hand infections allows appropriate and efficient administration of antibiotics. Methicillin-resistant S aureus is the most commonly cultured bacteria in the hand. However, polymicrobial infections have become increasingly more common. Although incidences of polymicrobial infections increased over the study period in this series, clinical judgment should be exercised before initiating broad-spectrum antibiotic coverage.

Community-acquired methicillin-resistant Staphylococcus aureus hand infections in the pediatric population

PURPOSE

Recent studies have reported rates of methicillin-resistant Staphylococcus aureus (MRSA) hand infections in patients without risk factors ranging from 26% to 73%. The purpose of our study was to review a large series of pediatric hand infections to determine the rate of MRSA and identify potential risk factors.

METHODS

A retrospective review was performed on patients younger than 15 who were seen for hand infections (2001-2010). Patients were categorized according to medical problems, need for operation, abscess location, and mechanism of injury. Potential MRSA risk factors were assessed using a multivariate-regression model.

RESULTS

During the 10-year period, 415 patients were seen for hand infections. A total of 146 patients met the inclusion criteria: patients younger than 15 years of age who presented to the plastic surgery service requiring consultation for hand infections. The overall prevalence of MRSA-positive cultures was found to be 30%. The prevalence of MRSA was 29% in healthy patients and 0% in immunocompromised patients. The prevalence of MRSA increased in a linear fashion from patients without documentation of incision and drainage procedures to patients adequately treated with bedside incision and drainage to patients who required surgical drainage. There was a trend toward a higher prevalence of MRSA in deep space abscesses compared to other abscesses. Patients with a history of trauma and previous MRSA infections had a higher rate of MRSA than other patients.

CONCLUSIONS

Traditionally, MRSA has been associated with hospitalization, intravenous drug use, recent antibiotic use, and compromised immunity. In our study, more severe, deep-space abscesses requiring surgical drainage and patients with a history of previous MRSA infections were found to have a higher prevalence of MRSA. The immunocompromised patients had no cases of MRSA and had higher incidences of less virulent bacterial infections. This suggests that acquisition of community-acquired MRSA skin and soft tissue infections in children and adolescents might not be associated with the traditional risk factors.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.