Community-Acquired Skin and Soft Tissue Infections: Epidemiology and Management in Patients Presenting to the Emergency Department of a Tertiary Care Hospital

Background: Skin and soft tissue infections are one of the most common diseases presenting to the emergency department (ED). There is no study available on the management of Community-Acquired Skin and Soft Tissue Infections (CA-SSTIs) in our population recently. This study aims to describe the frequency and distribution of CA-SSTIs as well as their medical and surgical management among patients presenting to our ED. Methods: We conducted a descriptive cross-sectional study on patients presenting with CA-SSTIs to the ED of a tertiary care hospital in Peshawar, Pakistan. The primary objective was to estimate the frequency of common CA-SSTIs presenting to the ED and to assess the management of these infections in terms of diagnostic workup and treatment modalities used. The secondary objectives were to study the association of different baseline variables, diagnostic modalities, treatment modalities, and improvement with the surgical procedure performance for these infections. Descriptive statistics were obtained for quantitative variables like age. Frequencies and percentages were derived for categorical variables. The chi-square test was used to compare different CA-SSTIs in terms of categorical variables like diagnostic and treatment modalities. We divided the data into two groups based on the surgical procedure. A chi-square analysis was conducted to compare these two groups in terms of categorical variables. Results: Out of the 241 patients, 51.9% were males and the mean age was 34.2 years. The most common CA-SSTIs were abscesses, infected ulcers, and cellulitis. Antibiotics were prescribed to 84.2% of patients. Amoxicillin + Clavulanate was the most frequently prescribed antibiotic. Out of the total, 128 (53.11%) patients received some type of surgical intervention. Surgical procedures were significantly associated with diabetes mellitus, heart disease, limitation of mobility, or recent antibiotic use. There was a significantly higher rate of prescription of any antibiotic and anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) agents in the surgical procedure group. This group also saw a higher rate of oral antibiotics prescription, hospitalization, wound culture, and complete blood count. Conclusion: This study shows a higher frequency of purulent infections in our ED. Antibiotics were prescribed more frequently for all infections. Surgical procedures like incision and drainage were much lower even in purulent infections. Furthermore, beta-lactam antibiotics like Amoxicillin-Clavulanate were commonly prescribed. Linezolid was the only systemic anti-MRSA agent prescribed. We suggest physicians should prescribe antibiotics appropriate to the local antibiograms and the latest guidelines.


Introduction
Skin and soft tissue infections (SSTIs) are one of the most common diseases presented to the emergency department (ED) [1]. As of 2014, there were an estimated 29.7 SSTI-related emergency room visits per 1000 population in the ED of the United States [2].
Normally, many microorganisms colonize the skin without causing any harm. With any imbalance in the structural or functional protection of the skin, the pathogenic organisms spread in the layers of the skin, overgrow, and elicit acute or chronic inflammation [1]. This process is called infection. Some skin infections may result from a hematogenous spread of pathogens from a distant infection [1]. Most SSTIs are caused by streptococci and Staphylococcus aureus [3]. 1 1 1 1 1 1 The United States food and drug authority classified SSTIs as uncomplicated and complicated infections [4,5]. Uncomplicated SSTIs include simple abscesses, cellulitis, impetigo, and furuncles. Complicated SSTIs include severe infections like necrotizing infections, infected burn wounds, infected open ulcers, and deep abscesses requiring major surgical intervention. It also includes infections in diabetic patients and immunocompromised patients [4].
Most simple SSTIs self-resolve. Large, complicated, and/or painful SSTIs require medical attention. Depending upon the severity, infections may need antibiotics and/or a surgical procedure like syringe aspiration, incision and drainage (I/D), debridement and drainage (D/D), or even amputation [6]. In an outpatient department and infectious disease setting, the focus is to provide specific antibiotics tailored to the sensitivity results. However, in the emergency room, physicians are mainly concerned with empiric therapy [7].
Based on the suspected source of infection, the SSTIs can be divided into two groups: Community-acquired: infections in non-hospitalized patients; and healthcare-associated: when an infection is acquired during or soon after hospitalization [8]. The healthcare-associated infections are considered a major complication, so they are frequently studied everywhere.
Community-acquired skin and soft tissue infections (CA-SSTIs) are relatively less studied. There is no study available on the management of CA-SSTIs in our population. The main objective of our study was to describe the frequency and distribution of CA-SSTIs, as well as medical and surgical treatments employed for these infections in our ED. This can then be used for further study to improve our practices under the current guidelines.

Materials And Methods
We conducted a descriptive cross-sectional study on patients presenting with CA-SSTIs to the ED of a tertiary care hospital in Peshawar, Pakistan. After approval from the hospital ethics and research board, we collected data in the ED from 1 September 2022 to 31 October 2022.
Through a consecutive sampling technique, we included all the patients, of any age or gender, that presented with an active SSTI. We excluded the patients who did not consent to data collection, who visited for a follow-up of a past infection, and/or who, by definition, had a healthcare-associated infection. Any infection that presents 48 hours after hospital admission, within three days after discharge, or within 30 days of surgery, was called a healthcare-associated infection [9].
After informed verbal consent, we collected the required data on a pre-designed proforma (Appendices). This included the patient's biodata, baseline variables, comorbid conditions, diagnostic tests, and the treatment modalities used. A telephonic follow-up was conducted regarding the disease status after one and two weeks of the visit.

Data analysis
We collected data from 264 patients based on an anticipated frequency of 3.18% SSTIs in the ED and a 95% level of confidence [2]. Twenty-three patients were excluded due to deficient or incorrect information. The final analysis was carried out on 241 patients in Statistical Product and Service Solutions (SPSS) (IBM SPSS Statistics for Windows, Version 25.0, Armonk, NY).
Descriptive statistics were obtained for quantitative variables like age. Frequencies and percentages were derived for categorical variables including gender, age groups, clinical diagnosis, diagnostic tests, and treatment modalities used. The chi-square test was used to compare different SSTIs in terms of categorical variables like diagnostic modalities. A p-value of less than 0.05 was considered a statistically significant association.
We further divided the data into two groups based on the surgical procedure done: the surgical procedure group (those who underwent any surgical procedure including syringe aspiration, I/D, D/D, or amputation for a CA-SSTI), and the non-surgical procedure group. A chi-square analysis was conducted to compare these two groups in terms of categorical variables. A p-value of less the 0.05 was considered a statistically significant association.

ED: emergency department
Out of the total, 128 (53.11%) patients received some type of surgical intervention while 113 (46.8%) did not receive surgical intervention. Surgical procedures were significantly more common in patients with diabetes mellitus, heart disease, limitation of mobility, or recent antibiotic use. However, there was no significant difference between the two groups for other variables ( Table 3).

Variables
Overall (  All the associations were drawn using a two-sided chi-square test and the values are shown in percentages of the total procedures done or not done. a: p-value < 0.05 indicate significant association and are written in italic. b: CKD: chronic kidney disease c: CLD: chronic liver disease NOTE: The percentages may not add up to 100 due to rounding off. With respect to management, there was a significantly higher rate of prescription of any antibiotic and antimethicillin-resistant Staphylococcus aureus (anti-MRSA) antibiotics in the surgical procedure group. We also saw a higher rate of oral antibiotics prescription, hospitalization, wound culture, and complete blood count (CBC) in this group ( Table 4).
Although follow-up was included as a secondary objective of our study, only 129 patients responded to follow-up communication (53.3%). Using a univariate chi-square analysis on these 129 cases showed no statistically significant difference in improvement between the surgical and non-surgical groups (   Finally, we compared different CA-SSTIs in terms of the proportions of different diagnostic and treatment modalities using a univariate chi-square. We found a statistically significant association of the different SSTIs with wound culture (p<0.001), CBC (p<0.001), blood culture (p=0.014), and hospitalization (p<0.001).
There was no significant difference in the antibiotic prescription and surgical procedure for different CA-SSTIs ( Table 5).  a: p-value less than 0.05 is considered statistically significant and is written in italics b: CBC: Complete blood count

Discussion
SSTIs are common presentations in ED [10]. Mistry et al. reported that 51% of the SSTI patients treated in the ED were males and 49% were females [6]. In addition, 57% of their patients belonged to the 18-49 years age group. Our study showed 59% male patients versus 41% females. Most of our patients were in the 21-30 years age group (26.6%). The most common CA-SSTIs were abscesses, infected ulcers, and cellulitis.
Around half (53.1%) of our patients received some sort of surgical procedure and 84% received an antibiotic. The surgical procedure was strongly associated with diabetes, heart disease, limitation of mobility, and recent antibiotic use as these factors are associated with severe purulent infections.
Among the purulent infections, a surgical procedure was performed in 50.6% of abscesses, 80% of carbuncles, 33% of furuncles, 69% of infected cysts, and 80% of necrotizing fasciitis patients. The rate of antibiotic prescription was much higher in all these infections. Mistry et al. reported I/D in 27% of patients presenting with an SSTI to the ED with an antibiotic prescription rate of 85% overall. Like other hospitals, the instinctive practice of antibiotics prescription more than I/D exists in our setting as well.
Diagnosis of these infections is mostly clinical [1]. Guidelines suggest that CBC and wound culture should be ordered for all complicated SSTIs, and for those with sepsis should be ordered for blood culture as well [11]. These tests can be avoided in uncomplicated infections [1]. In our study, wound culture was ordered in 14% of patients, more commonly in the surgical procedure group (22.7%). CBC was also strongly associated with surgical procedures (p<0.001). Mistry et al. reported similar results with wound culture in 16% of patients, more common in those receiving an I/D. However, this study reported a higher rate of CBC and blood culture in the non-surgical group. Kamath et al. reported wound culture in all the patients (100%) undergoing I/D for an SSTI [11].
any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.