Fournier's gangrene with Streptococcus Anginosus in the setting of hidrandenitis suppurativa perineal abscess: A case report.

INTRODUCTION: Fournier's gangrene is a rare but life-threatening form of necrotizing soft tissue infection involving the perineal, genital, or perianal region, commonly caused by a mix of aerobic and anaerobic organisms. Initially discovered in dental abscesses, Streptococcus anginosus have been increasingly reported in pyogenic and systemic infections with abscess formation. We present a rare case of perineal abscess that developed into Fournier's gangrene in which the causative pathogen isolated was S. anginosus. PRESENTATION OF CASE: A 58-year-old male with uncontrolled type 2 diabetes, hypertension and hidradenitis suppurativa of the groin, presented with worsening testicular pain. He was found to have a necrotizing soft tissue infection of the perineum, consistent with Fournier's gangrene. He was successfully treated with multiple surgical debridement and broad-spectrum intravenous antibiotics. He was transitioned to oral antibiotics before transferring to a tertiary care facility for reconstruction. DISCUSSION: The setting of uncontrolled diabetes and hidradenitis suppurativa may be the likely etiology for this peculiar case of Fournier's gangrene secondary to S. anginosus. Compromised tissue integrity and impaired local immune defenses from these etiologies predisposes to the development of Fournier's gangrene. Historically, these abscesses typically resolve after intravenous antibiotics and incision and drainage. However, the abscess in this case did not resolve but rather progressed to Fournier's gangrene. Perineal abscesses that grow S. anginosus should raise a high index of suspicion for worse outcomes. CONCLUSION: In conclusion, we recommend a multidisciplinary approach and rapid diagnosis for the management of S. anginosus in the setting of a perineal abscess, with early aggressive surgical debridement and broad-spectrum antibiotics.

Competency in Robotic Surgery: Standard Setting for Robotic Suturing Using Objective Assessment and Expert Evaluation.

OBJECTIVE: Surgical skill assessment tools such as the End-to-End Assessment of Suturing Expertise (EASE) can differentiate a surgeon's experience level. In this simulation-based study, we define a competency benchmark for intraoperative robotic suturing using EASE as a validated measure of performance. DESIGN: Participants conducted a dry-lab vesicourethral anastomosis (VUA) exercise. Videos were each independently scored by 2 trained, blinded reviewers using EASE. Inter-rater reliability was measured with prevalence-adjusted bias-adjusted Kappa (PABAK) using 2 example videos. All videos were reviewed by an expert surgeon, who determined if the suturing skills exhibited were at a competency level expected for residency graduation (pass or fail). The Contrasting Group (CG) method was then used to set a pass/fail score at the intercept of the pass and fail cohorts' EASE score distributions. SETTING: Keck School of Medicine, University of Southern California. PARTICIPANTS: Twenty-six participants: 8 medical students, 8 junior residents (PGY 1-2), 7 senior residents (PGY 3-5) and 3 attending urologists. RESULTS: After 1 round of consensus-building, average PABAK across EASE subskills was 0.90 (Range 0.67-1.0). The CG method produced a competency benchmark EASE score of >35/39, with a pass rate of 10/26 (38%); 27% were deemed competent by expert evaluation. False positives and negatives were defined as medical students who passed and attendings who failed the assessment, respectively. This pass/fail score produced no false positives or negatives, and fewer JR than SR were considered competent by both the expert and CG benchmark. CONCLUSIONS: Using an absolute standard setting method, competency scores were set to identify trainees who could competently execute a standardized dry-lab robotic suturing exercise. This standard can be used for high stakes decisions regarding a trainee's technical readiness for independent practice. Future work includes validation of this standard in the clinical environment through correlation with clinical outcomes.

A Multi-institution Study on the Association of Virtual Reality Skills with Continence Recovery after Robot-assisted Radical Prostatectomy.

BACKGROUND: Virtual reality (VR) simulators are increasingly being used for surgical skills training. It is unclear what skills are best improved via VR, translate to live surgical skills, and influence patient outcomes. OBJECTIVE: To assess surgeons in VR and live surgery using a suturing assessment tool and evaluate the association between technical skills and a clinical outcome. DESIGN, SETTING, AND PARTICIPANTS: This prospective five-center study enrolled participants who completed VR suturing exercises and provided live surgical video. Graders provided skill assessments using the validated End-To-End Assessment of Suturing Expertise (EASE) suturing evaluation tool. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: A hierarchical Poisson model was used to compare skill scores among cohorts and evaluate the association of scores with clinical outcomes. Spearman's method was used to assess correlation between VR and live skills. RESULTS AND LIMITATIONS: Ten novices, ten surgeons with intermediate expertise (median 64 cases, interquartile range [IQR] 6-80), and 26 expert surgeons (median 850 cases, IQR 375-3000) participated in this study. Intermediate and expert surgeons were significantly more likely to have ideal scores in comparison to novices for the subskills needle hold angle, wrist rotation, and wrist rotation needle withdrawal (p < 0.01). For both intermediate and expert surgeons, there was positive correlation between VR and live skills for needle hold angle (p < 0.05). For expert surgeons, there was a positive association between ideal scores for VR needle hold angle and driving smoothness subskills and 3-mo continence recovery (p < 0.05). Limitations include the size of the intermediate surgeon sample and clinical data limited to expert surgeons. CONCLUSIONS: EASE can be used in VR to identify skills to improve for trainee surgeons. Technical skills that influence postoperative outcomes may be assessable in VR. PATIENT SUMMARY: This study provides insights into surgical skills that translate from virtual simulation to live surgery and that have an impact on urinary continence after robot-assisted removal of the prostate. We also highlight the usefulness of virtual reality in surgical education.

Defining the optimal time to appendectomy: A step toward precision surgery.

BACKGROUND: We aimed to investigate the association between time from admission to appendectomy on perioperative outcomes in order to determine optimal time-to-surgery windows. METHODS: We performed a retrospective review of all the appendectomies performed between July 2018 to May 2020. We first compared the perioperative outcomes using preselected time-to-surgery cut-offs, then determined optimal safe windows for surgery, and finally identified subgroups of patients who may require early intervention. RESULTS: Six hundred twenty-one appendectomies were performed in the time period. The patients with a time-to-surgery of ≥12 hours had a significantly longer length of stay (median 2 days [interquartile range 1-3] vs 3 days [interquartile range 2-4], mean difference = 0.74 [95% confidence interval 0.32-1.17, P = .0006]) and higher 30-day readmission risk (odds ratio 2.58, 95% confidence interval 1.12-5.96, P = .0266) versus those with a time-to-surgery of <12 hours. These differences persisted when the time-to-surgery was dichotomized by <24 or ≥24 hours. A time-to-surgery beyond 25 hours was associated with a 3.34-fold increased odds of open conversion (P = .040), longer operation time (mean difference 15.8 mins, 95% confidence interval 3.4-28.3, P = .013) and longer postoperative length of stay (mean difference 10.3 hours, 95% confidence interval 3.4-20.2, P = .042) versus a time-to-surgery of <25 hours. The patients with time-to-surgery beyond 11 hours had a 1.35-fold increased odds of 30-day readmission (95% confidence interval 1.02-5.43, P = .046) compared with those who underwent appendectomy before 11 hours. Older patients, patients with American Society of Anesthesiologist score II to III, and individuals with long duration of preadmission symptoms had higher risk of prolonged operation time, open conversion, increased length of stay, and postoperative morbidity with increasing time-to-surgery. CONCLUSION: This study identified the safe windows for appendectomy to be 11 to 25 hours from admission for most perioperative outcomes. However, certain patient subgroups may be less tolerant of surgical delays.

Measuring health-related social deprivation in small areas: development of an index and examination of its association with cancer mortality.

BACKGROUND: The small-area deprivation indices are varied across countries due to different social context and data availability. Due to lack of chronic disease-related social deprivation index (SDI) in Hong Kong, China, this study aimed to develop a new SDI and examine its association with cancer mortality. METHODS: A total of 14 socio-economic variables of 154 large Tertiary Planning Unit groups (LTPUGs) in Hong Kong were obtained from 2016 population by-census. LTPUG-specific all-cause and chronic condition-related mortality and chronic condition inpatient episodes were calculated as health outcomes. Association of socio-economic variables with health outcomes was estimated for variable selection. Candidates for SDI were constructed with selected socio-economic variables and tested for criterion validity using health outcomes. Ecological association between the selected SDI and cancer mortality were examined using zero-inflated negative binomial regression. RESULTS: A chronic disease-related SDI constructed by six area-level socio-economic variables was selected based on its criterion validity with health outcomes in Hong Kong. It was found that social deprivation was associated with higher cancer mortality during 2011-2016 (most deprived areas: incidence relative risk [IRR] = 1.40, 95% confidence interval [CI]: 1.27-1.55; second most deprived areas: IRR = 1.34, 95%CI: 1.21-1.48; least deprived areas as reference), and the cancer mortality gap became larger in more recent years. Excess cancer death related to social deprivation was found to have increased through 2011-2016. CONCLUSIONS: Our newly developed SDI is a valid and routinely available measurement of social deprivation in small areas and is useful in resource allocation and policy-making for public health purpose in communities. There is a potential large improvement in cancer mortality by offering relevant policies and interventions to reduce health-related deprivation. Further studies can be done to design strategies to reduce the expanding health inequalities between more and less deprived areas.

Reduced dimethyl sulfoxide concentrations successfully cryopreserve human hematopoietic stem cells with multi-lineage long-term engraftment ability in mice.

BACKGROUND AIMS: The cryopreservation of hematopoietic stem cells (HSCs) in dimethyl sulfoxide (DMSO) is used widely, but DMSO toxicity in transplant patients and the effects of DMSO on the normal function of cryopreserved cells are concerns. To address these issues, in vitro and clinical studies have explored using reduced concentrations of DMSO for cryopreservation. However, the effect of reducing DMSO concentration on the efficient cryopreservation of HSCs has not been directly measured. METHODS: Cryopreservation of human bone marrow using 10%, 7.5% and 5% DMSO concentrations was examined. Cell counting, flow cytometry and colony assays were used to analyze different cell populations. The recovery of stem cells was enumerated using extreme limiting dilution analysis of long-term multi-lineage engraftment in immunodeficient mice. Four different methods of analyzing human engraftment were compared to ascertain stem cell engraftment: (i) engraftment of CD33+ myeloid, CD19+ B-lymphoid, CD235a+ erythroid and CD34+ progenitors; (ii) engraftment of the same four populations plus CD41+CD42b+ platelets; (iii) engraftment of CD34++CD133+ cells; and (iv) engraftment of CD34++CD38- cells. RESULTS: Hematopoietic colony-forming, CD34++/+, CD34++CD133+ and CD34++CD38- cells were as well preserved with 5% DMSO as they were with the higher concentrations tested. The estimates of stem cell frequencies made in the xenogeneic transplant model did not show any significant detrimental effect of using lower concentrations of DMSO. Comparison of the different methods of gauging stem cell engraftment in mice led to different estimates of stem cell numbers, but overall, all measures found that reduced concentrations of DMSO supported the cryopreservation of HSCs. CONCLUSION: Cryopreservation of HSCs in DMSO concentrations as low as 5% is effective.

A bioinspired and chemically defined alternative to dimethyl sulfoxide for the cryopreservation of human hematopoietic stem cells.

The cryopreservation of hematopoietic cells using dimethyl sulfoxide (DMSO) and serum is a common procedure used in transplantation. However, DMSO has clinical and biological side effects due to its toxicity, and serum introduces variation and safety risks. Inspired by natural antifreeze proteins, a novel class of ice-interactive cryoprotectants was developed. The corresponding DMSO-, protein-, and serum-free cryopreservation media candidates were screened through a series of biological assays using human cell lines, peripheral blood cells, and bone marrow cells. XT-Thrive-A and XT-Thrive-B were identified as lead candidates to rival cryopreservation with 10% DMSO in serum based on post-thaw cell survival and short-term proliferation assays. The effectiveness of the novel cryopreservation media in freezing hematopoietic stem cells from human whole bone marrow was assessed by extreme limiting dilution analysis in immunodeficient mice. Stem cell frequencies were measured 12 weeks after transplant based on bone marrow engraftment of erythroid, myeloid, B-lymphoid, and CD34+ progenitors measured by flow cytometry. The recovered numbers of cryopreserved stem cells were similar among XT-Thrive A, XT-Thrive B, and DMSO with serum groups. These findings show that cryoprotectants developed through biomimicry of natural antifreeze proteins offers a substitute for DMSO-based media for the cryopreservation of hematopoietic stem cells.

Validation of the modified Ranson versus Glasgow score for pancreatitis in a Singaporean population.

BACKGROUND: The characteristics of patients with acute pancreatitis in multi-ethnic Singapore differ from that of the populations used in formulating the modified Ranson and Glasgow scores. The use of these scoring systems has not previously been validated in the Singaporean setting. This study aims to validate and compare the prognostic use of the modified Ranson and Glasgow scores, and to determine the superiority of one score over the other in predicting the outcome for acute pancreatitis in the Singaporean population. METHODS: This is a 3-year retrospective study of patients diagnosed with acute pancreatitis at our centre. Patients with chronic pancreatitis, acute on chronic pancreatitis, iatrogenic pancreatitis, pancreatic cancer as well as those with incomplete Ranson or Glasgow scores were excluded from the study. Case notes and computer records were reviewed for local complications of pancreatitis and organ failure. Receiver operator characteristic (ROC) curves of the Ranson and Glasgow scores were plotted for the prediction of severity and mortality. RESULTS: Between January 2010 and December 2012, 230 cases were diagnosed with acute pancreatitis. A majority of the patients had mild pancreatitis (n = 194, 84.3%), and the overall 30-day mortality rate was 3.5% (n = 8). ROC of the Ranson and Glasgow scoring systems for mortality showed an area under curve (AUC) of 0.854 (P = 0.001) and 0.776 (P = 0.008), respectively. For severity, the AUC for the modified Ranson and Glasgow score was calculated to be 0.694 and 0.668, respectively. CONCLUSIONS: The ROC curves of Ranson and Glasgow scores for mortality are comparable with that published in earlier studies. In a Singaporean population, the Ranson score is more accurate in the prediction of mortality. However, both scoring systems are poor predictors for severity of acute pancreatitis.