[Surgical site infection and perioperative antibiotics in dermatosurgery]. / Postoperative Infektionen und perioperative Antibiose in der Dermatochirurgie.

BACKGROUND: Postoperative wound infections represent the most common complication in dermatosurgery. Given the low incidence and heterogeneous data, no standards for perioperative antibiotic prophylaxis (PAP) have been established in clinical practice. OBJECTIVES: To summarize the current evidence on risk factors for postoperative wound infection in dermatosurgery and the new recommendations on PAP. MATERIALS AND METHODS: Relevant study data and current recommendations were summarized descriptively. RESULTS: Current evidence suggests that the following factors are associated with an increased risk of wound infection after dermatosurgical procedures: surgery to the lower extremity or the ear, postoperative hemorrhage, defect closure by flap or skin graft, large wound defect, immunosuppression, and male sex. Probably not affecting the risk of infection are diabetes, obesity, age, smoking, use of a blood thinner, multiple surgeries, or wound healing by second intention. Not all risk factors affect the risk of infection equally. They must be weighted differently and only in combination do they increase the risk of wound infection in a clinically relevant way. According to a current position paper of the German Society for Dermatosurgery, the indication for PAP should be made individually and only if multiple factors are present. Furthermore, patients with increased risk for bacterial endocarditis or hematogenic endoprosthesis infection should receive PAP prior to septic skin surgery. CONCLUSION: In dermatologic surgery, PAP should be restricted to patients at high risk for wound infection. Further indications are the prevention of bacterial endocarditis and hematogenic endoprosthesis infection in high-risk individuals prior to septic surgery.

Serum levels of serum amyloid A, interleukin-6 and C-reactive protein correlate with severity of hidradenitis suppurativa.

BACKGROUND: Validated biomarkers enabling an objective, dynamic assessment of hidradenitis suppurativa (HS) disease severity do not exist. The aim of our study was to determine the serum concentration of four potential biomarkers with respect to HS disease severity. METHODS: We recruited 50 patients with hidradenitis suppurativa. After obtaining informed consent, patients were requested to fill out multiple questionnaires. Severity of HS was determined based on Hurley and Sartorius scores by an experienced dermatologist. Blood sampling included Serum Amyloid A (SAA), Interleukin-6 (IL-6), C-reactive protein (CRP) and S100 protein (S100) in a certified laboratory. RESULTS: Moderate and statistically significant correlations of SAA, IL-6 and CRP with the clinical scores Hurley and Sartorius were observed. The respective Spearman's correlation coefficients (r) were: Hurley 0.38, 0.46, 0.35 and Sartorius 0.51, 0.48, 0.48. No relevant changes were detected when comparing S100 to both Hurley (r=0.06) and Sartorius (r=0.09). CONCLUSIONS: Our data suggest that an association between SAA, IL-6, CRP and HS disease severity could exist. Further research is needed to define their potential as biomarkers for quantifying and monitoring disease activity and response to treatment.

Perioperative antibiotic prophylaxis in skin surgery - Position paper of the Antibiotic Stewardship working group of the German Society for Dermatologic Surgery (DGDC), Part 2: Special indications and situations.

In addition to prevention of surgical site infections after skin surgery, perioperative antibiotic prophylaxis (PAP) aims to prevent the occurrence of other postoperative infectious complications, especially bacterial endocarditis and hematogenous joint prosthesis infections. This article discusses specific indications for the use of PAP. For example, patients who have undergone any type of heart valve replacement, including transcatheter valve replacement or use of prosthetic material to correct the heart valve, or patients who have experienced bacterial endocarditis, require PAP during skin surgery on mucosal membranes or ulcerated tumors. The use of PAP in special situations such as secondary wound healing, septic dermatosurgery or ulcer surgery is also presented and discussed in detail in this paper based on the current scientific literature. This paper represents the second part of the position paper of the Antibiotic Stewardship Working Group of the German Society for Dermatologic Surgery (DGDC) and summarizes evidence-based recommendations for the administration of PAP during skin surgery for special indications and situations. This is particularly important because, as detailed in Part 1 of this position paper, PAP can and usually should be avoided in skin surgery.

Surgical site infection in skin surgery-An observational study.

BACKGROUND: Surgical site infection (SSI) has a significant impact on patients' morbidity and aesthetic results. OBJECTIVE: To identify risk factors for SSI in dermatologic surgery. PATIENTS AND METHODS: This prospective, single-centre, observational study was performed between August 2020 and May 2021. Patients that presented for dermatologic surgery were included and monitored for the occurrence of SSI. For statistical analysis, we used a mixed effects logistic regression model. RESULTS: Overall, 767 patients with 1272 surgical wounds were included in the analysis. The incidence of SSI was 6.1%. Significant risk factors for wound infection were defect size over 10cm2 (OR 3.64, 95% confidence interval [CI] 1.80-7.35), surgery of cutaneous malignancy (OR 2.96, CI 1.41-6.24), postoperative bleeding (OR 4.63, CI 1.58-13.53), delayed defect closure by local skin flap (OR 2.67, CI 1.13-6.34) and localisation of surgery to the ear (OR 7.75, CI 2.07-28.99). Wound localisation in the lower extremities showed a trend towards significance (OR 3.16, CI 0.90-11.09). Patient-related factors, such as gender, age, diabetes, or immunosuppression, did not show a statistically significant association with postoperative infection. CONCLUSION: Large defects, surgery of cutaneous malignancy, postoperative bleeding, and delayed flap closure increase the risk for SSI. High-risk locations are the ears and lower extremities.

Antibiotic Prophylaxis of Surgical Site Infections in Cutaneous Surgery: A Prospective Observational Study.

The use of perioperative antibiotic prophylaxis in cutaneous surgery is controversial due to unclear efficacy and, thus, potentially unnecessary side-effects. This prospective observational study analysed the efficacy of oral perioperative antibiotic prophylaxis in preventing surgical site infections. Adult patients undergoing cutaneous surgery between August 2020 and May 2021 at Ludwig-Maximilian University Hospital Munich, Germany, without prior signs of infection were eligible. Propensity score weighting was used for covariate adjustment to account for non-randomized treatment assignment. Of 758 included patients, 23 received perioperative antibiotic prophylaxis (3.0%). In this group, a surgical site infection occurred in 1 of 45 lesions (2.2%) compared with 76 of 1,189 lesions (6.5%) in the group without perioperative antibiotic prophylaxis (735 patients, 97.0%). With covariate adjustment, the odds ratio for the occurrence of a surgical site infection in patients receiving perioperative antibiotic prophylaxis was 0.114 (95% confidence interval 0.073-0.182; p <0.001) on a per lesion level. The number of lesions needed to treat to prevent 1 surgical site infection was 17.6 (95% confidence interval 16.8-19.2). This prospective observational study shows a reduction in the incidence of surgical site infection in cutaneous surgery performed with perioperative antibiotic prophylaxis. The large size difference between the 2 study groups limits the study.

Procedure-Related Risk Factors for Surgical Site Infection in Dermatologic Surgery.

BACKGROUND: Identifying risk factors is essential for preventing surgical site infections (SSIs) in dermatologic surgery. OBJECTIVE: To analyze whether specific procedure-related factors are associated with SSI. METHODS: This systematic review of the literature included MEDLINE, EMBASE, CENTRAL, and trial registers. The Newcastle-Ottawa Scale was used for risk bias assessment. If suitable, the authors calculated risk factors and performed meta-analysis using random effects models. Otherwise, data were summarized narratively. RESULTS: Fifteen observational studies assessing 25,928 surgical procedures were included. Seven showed good, 2 fair, and 6 poor study quality. Local flaps (risk ratio [RR] 3.26, 95% confidence intervall [CI] 1.92-5.53) and skin grafting (RR 2.95, 95% CI 1.37-6.34) were associated with higher SSI rates. Simple wound closure had a significantly lower infection risk (RR 0.34, 95% CI 0.25-0.46). Second intention healing showed no association with SSI (RR 1.82, 95% CI 0.40-8.35). Delayed wound closure may not affect the SSI rate. The risk for infection may increase with the degree of preoperative contamination. There is limited evidence whether excisions >20 mm or surgical drains are linked to SSI. CONCLUSION: Local flaps, skin grafting, and severely contaminated surgical sites have a higher risk for SSI. Second intention healing and probably delayed wound closure are not associated with postoperative wound infection.

Ex vivo confocal laser scanning microscopy: A diagnostic technique for easy real-time evaluation of benign and malignant skin tumours.

Ex vivo confocal laser scanning microscopy (ex vivo CLSM) is a novel diagnostic tool for a quick bedside evaluation of freshly excised tissue, comparable to histology. We aimed to assess the sensitivity and specificity of ex vivo CLSM in detecting malignant features, to validate its reliability in identifying various skin tumours based on a combination of confocal features and to evaluate the digital staining mode (DS). One-hundred twenty freshly excised skin samples from 91 patients were evaluated. Each lesion was screened for the presence of 23 predefined confocal criteria with ex vivo CLSM, followed by a histopathological examination. The diagnostic agreement between ex vivo CLSM and histology was 89.2%. The diagnostic accuracy of ex vivo CLSM in detecting malignancy reached a sensitivity of 98% and a specificity of 76%. Ex vivo CLSM enabled a rapid identification of the most common skin tumours, the tumour dignity and cytological features. The DS demonstrated a close resemblance to conventional histopathology.

Patient-dependent risk factors for wound infection after skin surgery: A systematic review and meta-analysis.

Postoperative wound infection in dermatologic surgery causes impaired wound healing, poor cosmetic outcome and increased morbidity. Patients with a high-risk profile may benefit from perioperative antibiotic prophylaxis. The objective of this systematic review was to identify risk factors for surgical site infection after dermatologic surgery. In this article, we report findings on patient-dependent risk factors. The literature search included MEDLINE, EMBASE, CENTRAL and trial registers. We performed meta-analysis, if studies reported sufficient data to calculate risk ratios with 95% confidence intervals. Study quality was assessed according to the Newcastle-Ottawa-Scale. Seventeen observational studies that analysed 31213 surgical wounds were eligible for inclusion. Fourteen studies qualified for meta-analysis. Nine studies showed good, three fair and five poor methodological quality. The reported incidence of surgical site infection ranged from 0.96% to 8.70%. Meta-analysis yielded that male gender and immunosuppression were significantly associated with higher infection rates. There was a tendency towards a higher infection risk for patients with diabetes, without statistical significance. Meta-analysis did not show different infection rates after excision of squamous cell carcinoma or basal cell carcinoma, but studies were substantially heterogenous. There was no significant association between risk for wound infection and smoking, age over 60 years, oral anti-aggregation or anti-coagulation or excision of malignant melanoma. In conclusion, the risk for surgical site infection in dermatologic surgery is low. Infection rates were increased significantly in male as well as immunosuppressed patients and non-significantly in diabetics.

Are Specific Body Sites Prone for Wound Infection After Skin Surgery? A Systematic Review and Meta-Analysis.

INTRODUCTION: Identifying risk factors for wound infection may guide clinical practice for optimal use of perioperative antibiotic prophylaxis in dermatologic surgery. OBJECTIVE: To summarize the current evidence whether specific body sites have higher risks for surgical site infections (SSI). METHODS: The systematic literature search included MEDLINE, Embase, CENTRAL, and trial registers. Only observational studies qualified for inclusion and meta-analysis. We assessed the risk of bias according to the Newcastle-Ottawa Scale. RESULTS: Eighteen studies with 33,086 surgical wounds were eligible. Eight studies were of good, 4 of fair, and 6 of poor quality. The mean infection rate was 4.08%. Meta-analysis showed that the lips had significantly higher infection rates. The lower extremity and ears had or tended toward a higher risk for infection, but studies were clinically heterogeneous. A large prospective trial found that surgical wounds on the hands were at higher risk for infection. The trunk showed the lowest infection rate. The risk for SSI in other body locations was not different or remained uncertain because of substantial heterogeneity among studies. CONCLUSION: Lips, lower extremities, and probably ears and hands may have a higher risk for wound infection after skin surgery. The trunk showed the lowest infection rate.

Detection of relevant extracardiac findings on coronary computed tomography angiography vs. invasive coronary angiography.

OBJECTIVES: To compare the detection of relevant extracardiac findings (ECFs) on coronary computed tomography angiography (CTA) and invasive coronary angiography (ICA) and evaluate the potential clinical benefit of their detection. METHODS: This is the prespecified subanalysis of ECFs in patients presenting with a clinical indication for ICA based on atypical angina and suspected coronary artery disease (CAD) included in the prospective single-center randomized controlled Coronary Artery Disease Management (CAD-Man) study. ECFs requiring immediate therapy and/or further workup including additional imaging were defined as clinically relevant. We evaluated the scope of ECFs in 329 patients and analyzed the potential clinical benefit of their detection. RESULTS: ECFs were detected in 107 of 329 patients (32.5%; CTA: 101/167, 60.5%; ICA: 6/162, 3.7%; p < .001). Fifty-nine patients had clinically relevant ECFs (17.9%; CTA: 55/167, 32.9%; ICA: 4/162, 2.5%; p < .001). In the CTA group, ECFs potentially explained atypical chest pain in 13 of 101 patients with ECFs (12.9%). After initiation of therapy, chest pain improved in 4 (4.0%) and resolved in 7 patients (6.9%). Follow-up imaging was recommended in 33 (10.0%; CTA: 30/167, 18.0%; ICA: 3/162, 1.9%) and additional clinic consultation in 26 patients (7.9%; CTA: 25/167, 15.0%; ICA: 1/162, 0.6%). Malignancy was newly diagnosed in one patient (0.3%; CTA: 1/167, 0.6%; ICA: 0). CONCLUSIONS: In this randomized study, CTA but not ICA detected clinically relevant ECFs that may point to possible other causes of chest pain in patients without CAD. Thus, CTA might preclude the need for ICA in those patients. TRIAL REGISTRATION: NCT Unique ID: 00844220 KEY POINTS: • CTA detects ten times more clinically relevant ECFs than ICA. • Actionable clinically relevant ECFs affect patient management and therapy and may thus improve chest pain. • Detection of ECFs explaining chest pain on CTA might preclude the need for performing ICA.

Machine Learning Based Prediction of Squamous Cell Carcinoma in Ex Vivo Confocal Laser Scanning Microscopy.

Image classification with convolutional neural networks (CNN) offers an unprecedented opportunity to medical imaging. Regulatory agencies in the USA and Europe have already cleared numerous deep learning/machine learning based medical devices and algorithms. While the field of radiology is on the forefront of artificial intelligence (AI) revolution, conventional pathology, which commonly relies on examination of tissue samples on a glass slide, is falling behind in leveraging this technology. On the other hand, ex vivo confocal laser scanning microscopy (ex vivo CLSM), owing to its digital workflow features, has a high potential to benefit from integrating AI tools into the assessment and decision-making process. Aim of this work was to explore a preliminary application of CNN in digitally stained ex vivo CLSM images of cutaneous squamous cell carcinoma (cSCC) for automated detection of tumor tissue. Thirty-four freshly excised tissue samples were prospectively collected and examined immediately after resection. After the histologically confirmed ex vivo CLSM diagnosis, the tumor tissue was annotated for segmentation by experts, in order to train the MobileNet CNN. The model was then trained and evaluated using cross validation. The overall sensitivity and specificity of the deep neural network for detecting cSCC and tumor free areas on ex vivo CLSM slides compared to expert evaluation were 0.76 and 0.91, respectively. The area under the ROC curve was equal to 0.90 and the area under the precision-recall curve was 0.85. The results demonstrate a high potential of deep learning models to detect cSCC regions on digitally stained ex vivo CLSM slides and to distinguish them from tumor-free skin.

Ex-vivo fluorescence confocal microscopy with digital staining for characterizing basal cell carcinoma on frozen sections: A comparison with histology.

Ex-vivo fluorescence confocal microscopy (FCM) has been used on fresh tissue, but there is little experience on frozen sections. We evaluated the applicability of FCM on frozen sections of basal cell carcinomas (BCCs), stained with acridine orange and digitally colored to simulate hematoxylin and eosin (H&E) dyes. We compared our diagnostic accuracy in detecting and subtyping BCCs with FCM to our gold standard (H&E stained frozen sections used in 3D horizontal micrographic surgery). Fourty-six primary BCCs were analyzed for free margins as well as histological subtype with all FCM modes and conventional H&E staining. Adnexa, artifacts and diagnostic confidence were evaluated. Free margins were identified with a sensitivity and specificity of 92% and 91%. Concordance for tumor subtype was 88%. FCM may be used on both fresh tissue and frozen samples, although with reduced performance and different artifacts. The device is useful for the intraoperative diagnosis, subtyping and margin-mapping of BCCs.

Coronary Artery Disease: Analysis of Diagnostic Performance of CT Perfusion and MR Perfusion Imaging in Comparison with Quantitative Coronary Angiography and SPECT-Multicenter Prospective Trial.

Purpose To compare the diagnostic performance of stress myocardial computed tomography (CT) perfusion with that of stress myocardial magnetic resonance (MR) perfusion imaging in the detection of coronary artery disease (CAD). Materials and Methods All patients gave written informed consent prior to inclusion in this institutional review board-approved study. This two-center substudy of the prospective Combined Noninvasive Coronary Angiography and Myocardial Perfusion Imaging Using 320-Detector Row Computed Tomography (CORE320) multicenter trial included 92 patients (mean age, 63.1 years ± 8.1 [standard deviation]; 73% male). All patients underwent perfusion CT and perfusion MR imaging with either adenosine or regadenoson stress. The predefined reference standards were combined quantitative coronary angiography (QCA) and single-photon emission CT (SPECT) or QCA alone. Results from coronary CT angiography were not included, and diagnostic performance was evaluated with the Mantel-Haenszel test stratified by disease status. Results The prevalence of CAD was 39% (36 of 92) according to QCA and SPECT and 64% (59 of 92) according to QCA alone. When compared with QCA and SPECT, per-patient diagnostic accuracy of perfusion CT and perfusion MR imaging was 63% (58 of 92) and 75% (69 of 92), respectively (P = .11); sensitivity was 92% (33 of 36) and 83% (30 of 36), respectively (P = .45); and specificity was 45% (25 of 56) and 70% (39 of 56), respectively (P < .01). When compared with QCA alone, diagnostic accuracy of CT perfusion and MR perfusion imaging was 82% (75 of 92) and 74% (68 of 92), respectively (P = .27); sensitivity was 90% (53 of 59) and 69% (41 of 59), respectively (P < .01); and specificity was 67% (22 of 33) and 82% (27 of 33), respectively (P = .27). Conclusion This multicenter study shows that the diagnostic performance of perfusion CT is similar to that of perfusion MR imaging in the detection of CAD. © RSNA, 2017 Online supplemental material is available for this article.