A Trial of Antibiotics for Smaller Skin Abscesses

Molecular analysis of an increase in trimethoprim/sulfamethoxazole-resistant MRSA reveals multiple introductions into a tertiary care hospital, Germany 2012-19

OBJECTIVES

Increasing spread of resistance could jeopardize the use of antifolates against MRSA infections.

METHODS

We compared the prevalence of phenotypic trimethoprim/sulfamethoxazole resistance in 20 534 clinical Staphylococcus aureus isolates (19 096 MSSA and 1438 MRSA) of non-redundant patients at Heidelberg University Hospital over 8 years and performed WGS on trimethoprim/sulfamethoxazole-resistant MRSA.

RESULTS

From 2012 to 2019, trimethoprim/sulfamethoxazole resistance in MSSA (674/19 096; 3.5%) ranged between 1.5% and 7.2% and in MRSA (135/1438; 9.4%) between 0.5% and 20.2%, reaching a peak in 2016 and 2018, respectively (Ptrend < 0.001). Trimethoprim/sulfamethoxazole resistance was more likely in outpatients than inpatients (P = 0.005), younger patients (P < 0.001), skin and soft tissue infections (SSTIs) (MRSA only, P = 0.05), submissions from pulmonology (MRSA only, P = 0.001), the upper respiratory tract (MSSA only, P < 0.001) and general surgery (MSSA only, P = 0.001). WGS of 76 trimethoprim/sulfamethoxazole-resistant MRSA revealed that 59% belonged to major pandemic CA-MRSA clones (ST22, ST8, ST398, ST772, ST30), 47% harboured Panton-Valentine leucocidin (PVL), 97% SCCmec IV/V, 71% dfrG and 28% dfrA. SNP-based phylogeny of trimethoprim/sulfamethoxazole-resistant MRSA core genomes favoured independent introduction over clonal expansion as the source, most prominently of dfrA+ trimethoprim/sulfamethoxazole-resistant ST22 MRSA from the Gaza Strip.

CONCLUSIONS

The presented results support that trimethoprim/sulfamethoxazole-resistant S. aureus, formerly associated with SSTI from outpatients and S. aureus in the (sub)tropics, is on the rise in the temperate zone, potentially due to migration. Closer monitoring of trimethoprim/sulfamethoxazole resistance in S. aureus is recommended to safeguard the effectiveness of antifolate compounds.

Therapeutic Effect of Topical Negative Pressure Therapy/Vacuum-Associated Closure Therapy on Cephalic Facial Skin Abscess

Objective: To evaluate the efficacy and safety of topical negative pressure therapy/vacuum-associated closure (TPN/VAC) in the treatment of cephalic facial skin abscess with infection. Methods: Forty-seven patients with cephalic facial skin abscesses were divided into two groups. The observation group was treated with negative pressure sealing drainage technique and primary wound suture. The control group was treated with abscess incision and drainage first; the second stage was wound suture after three to five days. The time and times of wound dressing, the pain score during wound dressing, the time of antibiotic use, and the recurrence rate were observed. Results: The wound healing time of the observation group was seven days, which was better than that of the control group for 10-12 days. The time of dressing change in the observation group was 14.9 ± 2.0 minutes (11-19 minutes), and the time of dressing change in the control group was 14.6 ± 2.6 minutes (10-20 minutes). There was no difference between the two groups (p > 0.05). The total number of dressing changes per patient in the observation group was three to five times, and the total number of dressing changes per patient in the observation group was five to eight times. There was a statistically significant difference between the two groups (p < 0.05). The pain score of the observation group was 3.2 ± 0.6 points (2-4 points), and the pain score of the control group was 5.1 ± 0.8 points (4-7 points). The difference between the two groups was statistically significant (p < 0.05). There was no recurrence in the observation group and two cases in the control group. Conclusion: Local negative pressure closed drainage technology can shorten the patient's healing course and reduce the duration of treatment, reduce the pain of dressing changes, improve prognosis, and have satisfactory therapeutic effect. It is a simple, effective, and safe technology, which is worthy of clinical application.

Increase in the prevalence of Panton-Valentine leukocidin and clonal shift in community-onset methicillin-resistant Staphylococcus aureus causing skin and soft-tissue infections in the Rhine-Neckar Region, Germany, 2012-2016

Methicillin-resistant Staphylococcus aureus (MRSA) remains a major challenge for patient care. Community-associated (CA)-MRSA often have a fitness and virulence advantage compared with their nosocomial counterparts. Increased mobility, travel activities and migration accelerate the intercontinental spread of virulent CA-MRSA strains. Outpatient clinics are the most important route of entry for CA-MRSA into hospitals. However, systematic data on CA-MRSA in Germany are limited. In this study, community-onset (CO)-MRSA skin and soft-tissue infection (SSTI) isolates in the Rhine-Neckar Region from 2012-2016 were characterised to gain an insight into their molecular epidemiology and to monitor potential introduction of virulent and dominant MRSA strains into our hospital. A total of 2475 patients with S. aureus SSTI were identified in the outpatient departments of our hospital, of which 94 (3.8%) were MRSA. In addition, 40.4% of the CO-MRSA harboured the virulence factor Panton-Valentine leukocidin (PVL). ST8-t008-MRSA-IVa/c (23.7%; 9/39) and ST80-t044-MRSA-IVc (15.8%; 6/38) were the predominant PVL-positive MRSA. Molecular typing and epidemiological data revealed that 42.6% (40/94) of strains could be traced back to a local origin and 44.7% (42/94) were endemic outside of Europe. Resistance to quinolones, clindamycin and macrolides was common, whilst resistance to trimethoprim/sulfamethoxazole, tetracycline, mupirocin, chlorhexidine and fusidic acid was low. No resistance to rifampicin, fosfomycin or linezolid was observed. This study provides insight into the clonal composition of CO-MRSA in the Rhine-Neckar Region. The increase of PVL-positive MRSA and the introduction of imported strains may affect the local MRSA landscape in the near future and should be monitored closely.

Import of community-associated, methicillin-resistant Staphylococcus aureus to Europe through skin and soft-tissue infection in intercontinental travellers, 2011-2016

OBJECTIVES

Recently, following import by travel and migration, epidemic community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has caused nosocomial outbreaks in Europe, sometimes with a fatal outcome. We describe clinico-epidemiological characteristics of CA-MRSA detected by the European Network for the Surveillance of imported S. aureus (www.staphtrav.eu) from May 2011 to November 2016.

METHODS

Sentinel surveillance at 13 travel clinics enrolling patients with travel-associated skin and soft-tissue infection (SSTI) and analysing lesion and nose swabs at one central laboratory.

RESULTS

A total of 564 independent case-patients with SSTI were enrolled and had 374 (67%) S. aureus-positive lesions, of which 14% (51/374) were MRSA. The majority of CA-MRSA isolates from SSTI were Panton-Valentine leucocidin (PVL) -positive (43/51, 84%). The risk of methicillin-resistance in imported S. aureus varied by travel region (p <0.001) and was highest in Latin America (16/57, 28%, 95% CI 17.0-41.5) and lowest in Sub-Saharan Africa (4/121, 3%, 95% CI 0.9-8.3). Major epidemic clones (USA300 / USA300 Latin-American Variant, Bengal Bay, South Pacific) accounted for more than one-third (19/51, 37%) of CA-MRSA imports. CA-MRSA SSTI in returnees was complicated (31/51 multiple lesions, 61%; 22/50 recurrences, 44%), led to health-care contact (22/51 surgical drainage, 43%; 7/50 hospitalization, 14%), was transmissible (13/47 reported similar SSTI in non-travelling contacts, 28%), and associated with S. aureus nasal colonization (28 of 51 CA-MRSA cases, 55%; 24 of 28 colonized with identical spa-type in nose and lesion, 85%).

CONCLUSIONS

Travel-associated CA-MRSA SSTI is a transmissible condition that leads to medical consultations and colonization of the infected host.