Etiology, characteristics, and outcomes of community-onset necrotizing fasciitis in Korea: A multicenter study

Laparoscopic cholecystectomy in calculous cholecystitis: are antibiotics necessary?

Laparoscopic cholecystectomy in patients with cholecystitis is considered the best, appropriate and safe method of treatment for gallstone disease. However, the role of antibiotic administration before or after cholecystectomy to reduce infectious complications, particularly surgical site infections, or mortality is less clear. Many patients receive empiric antibiotics, but the feasibility of their use has not been proven. Some guidelines suggest the use of antibiotic prophylaxis for all cholecystectomies, although current evidence does not indicate any benefit to this practice in the absence of risk factors. This review examines the results of antibiotic use in laparoscopic cholecystectomy for chronic and acute calculous cholecystitis. Most studies argue against the need to use prophylactic antibiotics during elective surgery in low-risk patients. In cases of mild and moderate acute cholecystitis, the use of antibiotics to prevent postoperative infectious complications has no evidence of effectiveness, although these recommendations are also ambiguous. It is not recommended to use postoperative antibiotics after elective laparoscopic cholecystectomy, as well as for mild or moderate acute cholecystitis. However, additional studies with well-defined patient populations and comparable outcomes are needed to better assess the most appropriate timing and duration of antibiotic use in patients undergoing laparoscopic cholecystectomy. We used MedLine database on the PubMed platform and the Cochrane library to search for literature sources.

Incidence of Bacteriobilia and the Correlation with Antibioticoprophylaxis in Low-Risk Patients Submitted to Elective Videolaparoscopic Cholecystectomy: A Randomized Clinical Trial

Cholelithiasis has a major impact on global health and affects an average of 20% of the Western population. The main risk factors are females, age over 40 years, obesity and pregnancy. Most of the time it is asymptomatic, but when there are symptoms, they are generally nonspecific. Bile was considered sterile, but today it is known that it contains a complex bacterial flora, which causes biofilm in the gallbladder and gallstones. Among the main bacteria associated with cholelithiasis are Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, species of Enterococcus spp. and Acinetobacter spp. Antibiotic prophylaxis is used in an attempt to reduce postoperative infections, especially at the surgical site. However, some authors found no relationship between the use of antibiotic prophylaxis and a lower risk of surgical site infection. Thus, the aim of this double-blind randomized clinical trial was to compare the existence or not of bacteriobilia in patients at low anesthetic risk who underwent videolaparoscopic cholecystectomy, and its correlation with the use of prophylactic antibiotics. This study included 40 patients between 18 and 65 years old, diagnosed with cholelithiasis, symptomatic or not, with low anesthetic risk classified by the American Society of Anesthesiology in ASA I or ASA II, without complications or previous manipulation of the bile duct, who underwent elective video cholecystectomy, divided into two groups: Experimental Group A (n = 20), which received 2 g of Cephalotin (first-generation Cephalosporin, Keflin®, ABL antibiotics, Cosmópolis, Brazil) during anesthetic induction, and Control Group B (n = 20), where no antibiotics were administered until bile collection. After the procedure, a bile sample was collected and culture and antibiogram were performed. In the sample, 22 (55%) were classified as ASA I and 18 (45%) as ASA II. It was observed that 81.8% of the patients who had a positive culture did not use antibiotics, against 18.2% of those who used prophylaxis. When comparing patients regarding anesthetic risk, ASA I patients had a positive culture in 9.1% of cases, against 90.9% in patients classified as ASA II. It was concluded that patients with higher anesthetic risk (ASA II) have a higher chance of bacteriobilia and benefit from antibiotic prophylaxis when compared to patients with lower anesthetic risk (ASA I).

Rapid diagnostics for skin and soft tissue infections: the current landscape and future potential

PURPOSE OF REVIEW

Managing antimicrobial therapy in patients with complicated skin and soft tissue infections (SSTI) constitutes a growing challenge due to the wide spectrum of potential pathogens and resistance phenotypes. Today, microbiological documentation relies on cultural methods. This review summarizes the available evidence regarding the clinical input of rapid microbiological diagnostic tools (RMDT) and their impact on the management of antimicrobial therapy in SSTI.

RECENT FINDINGS

Accurate tools are already available for the early detection of methicillin-resistant Staphylococcus aureus (MRSA) in SSTI samples and may help avoiding or shortening empirical anti-MRSA coverage. Further research is necessary to develop and evaluate RMDT detecting group A streptococci (e.g., antigenic test) and Gram-negative pathogens (e.g., multiplex PCR assays), including through point-of-care utilization. Next-generation sequencing (NGS) methods could provide pivotal information for the stewardship of antimicrobial therapy, especially in case of polymicrobial or fungal SSTI and in the immunocompromised host; however, a shortening in the turnaround time and prospective data regarding their therapeutic input are needed to better appraise the clinical positioning of these promising approaches.

SUMMARY

The clinical input of RMDT in SSTI is currently limited due to the scarcity of available dedicated assays and the polymicrobial feature of certain cases. NGS appears as a relevant tool but requires further developments before its implementation in routine clinical practice.

Clinical Impact of Staphylococcus aureus Skin and Soft Tissue Infections

The pathogenic bacterium Staphylococcus aureus is the most common pathogen isolated in skin-and-soft-tissue infections (SSTIs) in the United States. Most S. aureus SSTIs are caused by the epidemic clone USA300 in the USA. These infections can be serious; in 2019, SSTIs with S. aureus were associated with an all-cause, age-standardized mortality rate of 0.5 globally. Clinical presentations of S. aureus SSTIs vary from superficial infections with local symptoms to monomicrobial necrotizing fasciitis, which can cause systemic manifestations and may lead to serious complications or death. In order to cause skin infections, S. aureus employs a host of virulence factors including cytolytic proteins, superantigenic factors, cell wall-anchored proteins, and molecules used for immune evasion. The immune response to S. aureus SSTIs involves initial responders such as keratinocytes and neutrophils, which are supported by dendritic cells and T-lymphocytes later during infection. Treatment for S. aureus SSTIs is usually oral therapy, with parenteral therapy reserved for severe presentations; it ranges from cephalosporins and penicillin agents such as oxacillin, which is generally used for methicillin-sensitive S. aureus (MSSA), to vancomycin for methicillin-resistant S. aureus (MRSA). Treatment challenges include adverse effects, risk for Clostridioides difficile infection, and potential for antibiotic resistance.

Case Report: Necrotizing fasciitis caused by Staphylococcus aureus positive for a new sequence variant of exfoliative toxin E

Objectives: Necrotizing fasciitis (NF) caused by S. aureus is a rare, aggressive and rapidly progressing superficial fascia infection with a high mortality rate. The aim of this study was to identify virulence-related genes from a complete genome sequence of a methicillin-susceptible S. aureus (MSSA) isolate recovered from a monomicrobial case of NF.

Materials and methods: The MSSA isolate UMCG579 was cultured from a pus collection from the subcutis of a patient with NF. The genome of isolate UMCG579 was sequenced using MinION (Oxford Nanopore) and MiSeq (illumina) platforms.

Results: The genome of the UMCG579 isolate was composed of a 2,741,379 bp chromosome and did not harbor any plasmids. Virulence factor profiling identified multiple pore-forming toxin genes in the UMCG579 chromosome, including the Panton-Valentine leukocidin (PVL) genes, and none of the superantigen genes. The UMCG579 isolate harbored a new sequence variant of the recently described ete gene encoding exfoliative toxin (type E). A search in the GenBank database revealed that the new sequence variant (ete2) was exclusively found among isolates (n = 115) belonging to MLST CC152. While the majority of S. aureus ete-positive isolates were recovered from animal sources, S. aureus ete2-positive isolates originated from human carriers and human infections. Comparative genome analysis revealed that the ete2 gene was located on a 8777 bp genomic island.

Conclusion: The combination of two heterogeneously distributed potent toxins, ETE2 and PVL, is likely to enhance the pathogenic ability of S. aureus isolates. Since anti-virulence therapies for the treatment of S. aureus infections continue to be explored, the understanding of specific pathogenetic mechanisms may have an important prophylactic and therapeutic value. Nevertheless, the exact contribution of ETE sequence variants to S. aureus virulence in NF infections must be determined.

Current management of necrotizing soft-tissue infections

PURPOSE OF REVIEW

The aim of the article is to present recent epidemiological, microbiological, and clinical data for the surgical, antimicrobial, and adjunctive management of necrotizing soft-tissue infections (NSTI).

RECENT FINDINGS

NSTI can be caused by a broad variety of organisms. Reports about NSTI caused by multidrug-resistant bacteria are increasing. Owing to the rareness of NSTI, general clinical awareness is low and prompt diagnosis is often delayed. New diagnostic instruments (scoring systems, MRI) have either a low accuracy or are time consuming and cannot guide clinicians reliable currently. The value of adjunctive measures (intravenous immunoglobulin, hyperbaric oxygen therapy) is uncertain as well. Morbidity and mortality in NSTI remain high, ranging from 20 up to over 30%.

SUMMARY

Early radical surgical debridement and empirical broad-spectrum antimicrobial treatment remain the cornerstones of therapy in NSTI. Further clinical research is necessary to shorten diagnostic pathways and to optimize surgical, antimicrobial, and adjunctive treatment.

Necrotizing Soft Tissue Infection: A Single-Center Retrospective Study of Treatment and Outcomes

Introduction

Necrotizing fasciitis is a severe inflammatory disease of the body's soft tissue characterized by spreading rapidly and high mortality. Rapid surgical intervention along with other supportive measures of treatment have a great impact on the outcome of treatment.

Material and methods

This study was conducted by a retrospective medical record review of all patients with a microbiologically and clinically confirmed diagnosis of necrotizing fasciitis who were admitted to the general surgery department at the General Hospital Novi Pazar, Serbia, during the period between 2017 and 2020. Demographic, clinical, laboratory, and microbiology data were analyzed.

Results

A total of 13 cases were identified, which represents 0.21% of the total number of patients treated at the surgical department during the period January 2017 to November 2020. The mean age of patients was 55 years, with a male/female ratio of 1:1.6. All of them had at least one comorbidity and more than half had three or more. Diabetes, cardiovascular diseases, and obesity were the most common comorbidities. The most common causes of infection were Klebsiella spp, Pseudomonas aeruginosa, S. pyogenes, and S. aureus. All patients received multiple surgical interventions (mean 2.3).

Conclusion

Treating necrotizing fasciitis requires a multidisciplinary approach. Early diagnosis and rapid clinical response allow for better disease outcomes. Getting to know more about necrotizing fasciitis will help doctors make better decisions when treating it.

Risk factors associated with necrotizing fasciitis of the lower limbs: A multicenter case-control study

OBJECTIVE

The aim of this case-control study was to identify risk factors associated with necrotizing fasciitis (NF) of the lower limbs.

PATIENTS AND METHODS

We conducted a prospective case-control study in hospital dermatology departments in 5 sub-Saharan African countries over a 2-year period (April 2017 to July 2019). The cases were patients with NF of the lower limbs and the controls were patients with leg erysipelas. Each case was matched with two controls for age (±5 years) and sex. We analyzed local and general factors.

RESULTS

During the study period, 159 cases (73 females, 86 males) were matched with 318 controls. The mean age was 48.5±15.8 years for cases and 46.5±16.2 years for controls (P=0.24). The main local signs of NF were cutaneous necrosis (83.7%), pain (75.5%) and induration (42.1%). Multivariate analysis showed the following to be independent risk factors associated with NF of the lower limbs: obesity (odds ratio [OR]=2.10; 95% confidence interval [CI]: 1.21-3.42), diabetes (OR=3.97; 95% CI: 1.95-6.13), nicotine addiction (OR=5.07; 95% CI: 2.20-11.70), use of non-steroidal anti-inflammatory drugs (NSAIDs) (OR=7.85; 95% CI 4.60-14.21) and voluntary cosmetic depigmentation (OR=2.29; 95% CI: 1.19-3.73).

CONCLUSION

Our study documents the role of NSAID use at the onset of symptoms as a risk factor for NF of the lower limbs. However, the originality of our study consists in the identification of voluntary cosmetic depigmentation as a risk factor for NF of the lower limbs in sub-Saharan Africa patients. Our results also identified typical overarching factors such as diabetes, obesity and nicotine addiction. Knowing these factors and taking them into account will enable optimization of management strategies for these conditions.

Klebsiella pneumoniae necrotizing fasciitis on the upper lip in a patient with uncontrolled diabetes

A 60-year-old woman with a history of diabetes mellitus and chronic renal failure was admitted to the hospital with severe pain in the upper lip, which began 4 days prior to admission, accompanied by a bullous lesion and suspected cellulitis in the upper lip. Immediately after admission, as the patient´s general condition worsened, tests revealed a non-ST elevated myocardial infarction, septic embolism of the lung, as well as septic shock. Her upper lip suddenly presented a gangrenous and necrotic change, which the tissue and blood culture confirmed to be a Klebsiella pneumoniae infection. After a quick response, the patient’s general condition improved. Subsequently, serial debridement was performed to effectively clear away the purulent discharge. While under general anesthesia, the process confirmed full-layer necrosis of the upper lip including the orbicularis oris muscle. Almost half of the entire upper lip sustained a full-layer skin and soft tissue defect, with scar contracture. Six months later, to correct the drooling and lip sealing following the defects, a scar release and an Abbe flap coverage were performed considering both functional and aesthetic aspects. The follow-up revealed a favorable corrective result of the upper lip drooling, and the patient was satisfied from a functional perspective.

Treatment of Necrotizing Soft Tissue Infections: Antibiotics

Necrotizing soft tissue infections (NSTIs) are severe, life-threatening infections, and early therapeutic intervention is essential. Prompt administration of potent antimicrobial agents is pivotal, but inadequate empirical therapy is unfortunately common. Optimization of the antibiotic treatment strategy in NSTIs requires consideration of local epidemiology of causative pathogens and antimicrobial resistance patterns, knowledge on common pathogenetic mechanisms in NSTIs, and adaptations to pharmacokinetic and pharmacodynamic physiological changes in critically ill patients. In the present article we address all these issues, as well as review and compare contemporary guidelines for antimicrobial treatment of NSTIs from around the world.

Common traps/pitfalls and emergency diagnosis in dermatopathology

Although all diagnoses in dermatopathology are important, three main groups may be highlighted. One group includes diagnoses that need to be communicated to the treating physician as soon as possible (this review includes infectious process while erythema multiforme and related diseases are discussed elsewhere in this series). A second group has diagnoses significant for their association with syndromes or internal malignancies. And a third group includes malignant lesions that can be confused histologically with benign ones or lesions that have an aggressive behavior unexpected for their apparently low-grade histology. This manuscript describes some of these important diseases and the method we use to reach the diagnosis, and as such it may be considered to be a "survival" guide for the dermatopathologist.