Unspoken Truths: Mental Health Among Academic Surgeons

OBJECTIVE

To characterize the current state of mental health within the surgical workforce in the United States.

BACKGROUND

Mental illness and suicide is a growing concern in the medical community; however, the current state is largely unknown.

METHODS

Cross-sectional survey of the academic surgery community assessing mental health, medical error, and suicidal ideation. The odds of suicidal ideation adjusting for sex, prior mental health diagnosis, and validated scales screening for depression, anxiety, post-traumatic stress disorder (PTSD), and alcohol use disorder were assessed.

RESULTS

Of 622 participating medical students, trainees, and surgeons (estimated response rate=11.4%-14.0%), 26.1% (141/539) reported a previous mental health diagnosis. In all, 15.9% (83/523) of respondents screened positive for current depression, 18.4% (98/533) for anxiety, 11.0% (56/510) for alcohol use disorder, and 17.3% (36/208) for PTSD. Medical error was associated with depression (30.7% vs. 13.3%, P <0.001), anxiety (31.6% vs. 16.2%, P =0.001), PTSD (12.8% vs. 5.6%, P =0.018), and hazardous alcohol consumption (18.7% vs. 9.7%, P =0.022). Overall, 13.2% (73/551) of respondents reported suicidal ideation in the past year and 9.6% (51/533) in the past 2 weeks. On adjusted analysis, a previous history of a mental health disorder (aOR: 1.97, 95% CI: 1.04-3.65, P =0.033) and screening positive for depression (aOR: 4.30, 95% CI: 2.21-8.29, P <0.001) or PTSD (aOR: 3.93, 95% CI: 1.61-9.44, P =0.002) were associated with increased odds of suicidal ideation over the past 12 months.

CONCLUSIONS

Nearly 1 in 7 respondents reported suicidal ideation in the past year. Mental illness and suicidal ideation are significant problems among the surgical workforce in the United States.

Association of clinicopathologic and molecular factors with the occurrence of positive margins in breast cancer

PURPOSE

To explore the association of clinicopathologic and molecular factors with the occurrence of positive margins after first surgery in breast cancer.

METHODS

The clinical and RNA-Seq data for 951 (75 positive and 876 negative margins) primary breast cancer patients from The Cancer Genome Atlas (TCGA) were used. The role of each clinicopathologic factor for margin prediction and also their impact on survival were evaluated using logistic regression, Fisher's exact test, and Cox proportional hazards regression models. In addition, differential expression analysis on a matched dataset (71 positive and 71 negative margins) was performed using Deseq2 and LASSO regression.

RESULTS

Association studies showed that higher stage, larger tumor size (T), positive lymph nodes (N), and presence of distant metastasis (M) significantly contributed (p ≤ 0.05) to positive surgical margins. In case of surgery, lumpectomy was significantly associated with positive margin compared to mastectomy. Moreover, PAM50 Luminal A subtype had higher chance of positive margin resection compared to Basal-like subtype. Survival models demonstrated that positive margin status along with higher stage, higher TNM, and negative hormone receptor status was significant for disease progression. We also found that margin status might be a surrogate of tumor stage. In addition, 29 genes that could be potential positive margin predictors and 8 pathways were identified from molecular data analysis.

CONCLUSION

The occurrence of positive margins after surgery was associated with various clinical factors, similar to the findings reported in earlier studies. In addition, we found that the PAM50 intrinsic subtype Luminal A has more chance of obtaining positive margins compared to Basal type. As the first effort to pursue molecular understanding of the margin status, a gene panel of 29 genes including 17 protein-coding genes was also identified for potential prediction of the margin status which needs to be validated using a larger sample set.

Barriers to Academic Surgery in the US Armed Forces: A Study of the AAS Military Committee

INTRODUCTION

The purpose of this study is to explore current perceptions within the military surgery community to stratify key obstacles to pursuing a career in academic surgery and identify opportunities for mitigation.

METHODS

After receiving institutional review board approval, an anonymous electronic survey was distributed to military surgeons across all branches. Survey response data were collected and analyzed using chi-square test.

RESULTS

The response rate was approximately 22%. Of those who responded to the survey, most are interested in an academic career (61.5%); however, 64% believe this to be much more difficult as a military surgeon than as a civilian surgeon. The top three perceived obstacles include administrative obstacles (76.4%), operational commitments (65.8%), and lack of funding for academic pursuits (62.7%). Most respondents indicated that they have never received formal education regarding how to apply for research funding (84.5%) and most do not have a research mentor (60.9%). Additionally, 42.9% state that obstacles to an academic career in surgery impact their decision to leave the military. Younger surgeons were more likely to leave the military upon completion of their service commitment (67.9% versus 46.4% aged 20-39 y, P = 0.02).

CONCLUSIONS

We characterized the perceived challenges to academic surgery within the military. These barriers between academic surgery and military service risk medical force attrition, particularly in future generations of surgeons. Dedicated faculty billets (positions) with limited operational demands as well as associated mentorship and research funding may enhance the retention and productivity of military surgeons.

Trauma and Critical Care Military-Civilian Publications Increased After the COVID-19 Pandemic: A Literature Review

INTRODUCTION

There continues to be a growing demand for military-civilian partnerships (MCPs) in research collaborations developing medical trauma care in domestic and international affairs. The objective of this comprehensive review is to investigate the difference in the quantity of MCP trauma and critical care publications before and after the COVID-19 pandemic.

METHODS

A systematic literature review was performed for the calendar years 2018 and 2021 utilizing MEDLINE, Cochrane, and EMBASE databases. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we performed a three-tiered review of 603 English language articles to identify trauma-related military and/or civilian partners and describe the changes in geographical relationships.

RESULTS

A total of 96 (2018) and 119 (2021) articles met screening criteria for trauma and critical care studies and were used for final data extraction. Ultimately, 59 (2018) and 71 (2021) papers met the inclusion criteria of identifying trauma/critical care MCPs and identified both military and civilian partners. There was also an increase from 10 (2018) to 17 (2021) publications that mentioned advocacy for MCP. Using the author affiliations, four regional MCP types were recorded: of 2018 articles, locoregional (3.4%), US-national (47.5%), single international country (42.4%), and between multiple countries (6.8%); of 2021 articles, locoregional (15.5%), US-national (38%), single international country (29.6%), and between multiple countries (16.9%). There has been an increase in the number of locoregional and multinational MCPs and an overall increase in the number of collaborative trauma publications and MCP advocacy papers. A national geographical heat map was developed to illustrate the changes from 2018 to 2021.

CONCLUSIONS

There has been an increase in the number of recorded trauma and critical care MCP publications post-pandemic. The growth in the number of manuscripts in more regions post-pandemic suggests an increase in the recognition of collaborations that contribute not only to conflict readiness but also advancements in trauma and surgical care.

Impact of the progressive uptake of pneumococcal conjugate vaccines on the epidemiology and antimicrobial resistance of invasive pneumococcal disease in Gipuzkoa, northern Spain, 1998-2022

Objectives

To analyze the impact of pneumococcal conjugate vaccines (PCVs) on the incidence of invasive pneumococcal diseases (IPDs) and pneumococcal antibiotic resistance in Gipuzkoa, northern Spain for a 25 years period.

Methods

All cases of IPD confirmed by culture between 1998 and 2022 in a population of around 427,416 people were included. Pneumococci were serotyped and antimicrobial susceptibility was assessed by the EUCAST guidelines.

Results

Overall, 1,516 S. pneumoniae isolates were collected. Annual IPD incidence rates (per 100,000 people) declined from 19.9 in 1998-2001 to 11.5 in 2017-19 (42.2% reduction), especially in vaccinated children (from 46.7 to 24.9) and non-vaccinated older adult individuals (from 48.0 to 23.6). After PCV13 introduction, the decrease in the incidence of infections caused by PCV13 serotypes was balanced by the increase in the incidence of non-PCV13 serotypes. In the pandemic year of 2020, IPD incidence was the lowest: 2.81. The annual incidence rates of penicillin-resistant isolates also decreased, from 4.91 in 1998-2001 to 1.49 in 2017-19 and 0.70 in 2020. Since 2017, serotypes 14, 19A, and 11A have been the most common penicillin-resistant types. The incidence of erythromycin-resistant strains declined, from 3.65 to 1.73 and 0.70 in the same years.

Conclusion

PCV use was associated with declines in the incidence of IPD and the spread of non-vaccine serotypes, that balanced the beneficial effect off PCV13, some of them showing high rates of antibiotic resistance.

Impact of COVID on surgical case volume at military treatment facilities with surgical residencies

INTRODUCTION

The Military Health System (MHS) is tasked with the dual mission of providing medical care to beneficiaries while ensuring medical readiness. MHS provides care through a combination of military treatment facilities (MTF) ("direct care"; DC) & off-base civilian facilities ("purchased care"; PC). Given recent concerns regarding low surgical volume at MTFs, we sought to evaluate COVID's impact on elective and non-elective case volume at MTFs with surgical residencies.

METHODS

Retrospective review of 2017-2021 M2 database was performed on Tricare beneficiaries who underwent bariatric surgery or major colorectal surgery in the DC or PC market at, or, surrounding MTFs with surgical residencies. Procedures were identified using ICD-10 procedure codes and Medicare severity-diagnosis related groups. A detailed analysis was then performed on changes in case volume in the DC and PC markets.

RESULTS

5,698 bariatric and 5,517 major colorectal procedures were performed during the study period. There was an 84% vs 20% quarterly decrease in elective bariatric surgeries completed in the DC and PC markets from Q1 to Q2 2020. Pre to post-COVID (Q1 2017 - Q1 2020 vs Q3 2020 - Q4 2021) there was a decrease in the percentage of bariatric surgeries completed in the DC market (74.1% vs 55.0%, p = 0.001). Meanwhile, major colorectal surgery quarterly case volume remained unchanged in the DC (137 vs 125, p = 0.18) and PC (146 v 137, p = 0.13) markets, pre- and post-COVID.

DISCUSSION

Bariatric surgical case volume at MTFs disproportionately decreased during COVID when compared to the PC market and major colorectal cases. Bariatric case volume has rebounded in PC markets surpassing pre-COVID levels while DC case volume remains depressed. Further attention is warranted regarding decreased elective surgical case volume at MTFs.

Pressure-Enabled Drug Delivery (PEDD) of a class C TLR9 agonist in combination with checkpoint inhibitor therapy in a murine pancreatic cancer model

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Background: Systemic immunotherapy has had limited clinical benefit in pancreatic ductal adenocarcinoma (PDAC). This is thought to be due to its desmoplastic immunosuppressive tumor microenvironment in addition to high intratumoral pressures that limit drug delivery. Recent pre-clinical cancer models and early-phase clinical trials have demonstrated the efficacy of toll-like receptor 9 agonists (TLR9a), including the synthetic CpG oligonucleotide SD101, to stimulate innate and adaptive immune cells and eliminate suppressive myeloid cells. We hypothesized that Pressure Enabled Drug Delivery (PEDD) via Pancreatic Retrograde Venous Infusion (PRVI) of a TLR9a would improve responsiveness to systemic anti-programmed death receptor-1 (PD-1) checkpoint inhibitor therapy in a murine orthotopic PDAC model. Methods: Murine PDAC (KPC4580P) tumors were implanted into the pancreatic tails of C57BL/6J mice and treated 8 days after implantation. Mice were assigned to PRVI saline (pSAL, n=9), systemic anti-PD1 100 mcg/mouse on Day 0, 2 and 4 (sAPD1, n = 6), 30mcg PRVI TLR9a (pTLR9a, n=9), 30mcg systemic TLR9a (sTLR9a, n=7) on Day 0, and combination 30mcg PRVI TLR9a on Day 0 and systemic anti-PD1 100 mcg/mouse on Day 0, 2 and 4 (COMBO, n =9). Fluorescently-labeled TLR9a (radiant efficiency [RE]) was measured on day 1. Blood and tumors were collected at necropsy 12 days after infusion. Results: All mice survived to necropsy. Site of tumor fluorescence measurements revealed higher intensity fluorescence in pTLR9a compared to sTLR9a (7.5x10^5 vs. 2.4x10^5 RE, p= 0.048). Significantly lower MDSCs in the COMBO vs. pSAL are shown. Tumor weights were significantly lower in the COMBO group compared to pSAL (400 vs. 964 mg, p=0.003), and were also lower, although not significantly, than in the pTLR9a (400 vs. 518mg, p=0.50), and sAPD1 (400 vs. 645 mg, p = 0.70) groups. Conclusions: PEDD of TLR9a by PRVI with systemic anti-PD-1 demonstrated improved PDAC tumor control. These results support study of this combination therapy in PDAC patients and expansion of ongoing PEDD clinical trials. [Table: see text]

The 2020 Pandemics: Lessons Learned in Academic Surgery and Beyond

2020 was a significant year because of the occurrence of two simultaneous public health crises: the coronavirus pandemic and the public health crisis of racism brought into the spotlight by the murder of George Floyd. The coronavirus pandemic has affected all aspects of health care, particularly the delivery of surgical care, surgical education, and academic productivity. The concomitant public health crisis of racism and health inequality during the viral pandemic highlighted opportunities for action to address gaps in surgical care and the delivery of public health services. At the 2021 Academic Surgical Congress Hot Topics session on flexibility and leadership, we also explored how our military surgeon colleagues can provide guidance in leadership during times of crisis. The following is a summary of the issues discussed during the session and reflections on the important lessons learned in academic surgery over the past year.

Epidemiology and Clinical Features of Listeriosis in Gipuzkoa, Spain, 2010-2020

Background

Listeriosis continues to be one of the most important notifiable foodborne diseases. Nonetheless, in Spain, there are few data on the molecular epidemiology of Listeria monocytogenes infections in recent years.

Aim

To describe clinical features and the molecular epidemiology of human listeriosis over an 11-year period (2010–2020) in Gipuzkoa, Northern Spain.

Methods

A total of 111 isolates, all but one from invasive disease, were studied. Serotyping (agglutination and multiplex polymerase chain reaction [PCR]) and multilocus sequence typing were performed for all isolates. Antibiotic susceptibility was assessed by the broth microdilution method.

Results

The average annual incidence of listeriosis in non-pregnancy-associated cases was 1.55 per 100,000 population, with a 1-month mortality rate of 22.2%. In pregnant women, the average incidence was 0.45 cases per 1,000 pregnancies. Twenty-four sequence types were identified, serotype 4b ST1 (24.3%) being the most frequent followed by 1/2b ST87 (18.9%), which caused two long outbreaks in 2013–2014. A significant association was observed between ST219 and meningitis (p < 0.001). All isolates were susceptible to ampicillin as well as other antibiotics used in listeriosis treatment.

Conclusion

Despite current control measures, listeriosis continues to be an important cause of mortality in the elderly, preterm birth, and miscarriages in pregnant women. Improvements in the control and diagnosis of listeriosis are needed to reduce the impact of this infection on vulnerable populations.

Oxaliplatin-induced peripheral neuropathy can be minimized by pressurized regional intravascular delivery in an orthotopic murine pancreatic cancer model

PURPOSE

There is a great need to reduce the toxicity of chemotherapy used in the management of pancreatic ductal adenocarcinoma (PDAC). Here we explore if regional pressurized delivery of oxaliplatin can minimize peripheral neuropathy in mice.

METHODS

We used an orthotopic PDAC mouse model and delivered a single dose of oxaliplatin through the portal vein using a pressure-enabled system (pancreatic retrograde venous infusion, PRVI). We analyzed the effects of PRVI on tumor burden and peripheral neuropathy using histopathological and functional assays.

RESULTS

Tumor weights in mice treated with 2 mg/kg oxaliplatin using PRVI were significantly lower than in mice treated with the same dose systemically. This resulted in reduced peripheral neuropathy signatures in PRVI mice compared to the 20 mg/kg systemic dose required to achieve similar tumor control.

CONCLUSION

Regional delivery of highly cytotoxic agents using PRVI can reduce the therapeutic dose of these drugs, thereby lowering toxic side effects.

Outcomes with durvalumab after chemoradiotherapy in stage IIIA-N2 non-small-cell lung cancer: an exploratory analysis from the PACIFIC trial

Background

The phase III PACIFIC trial (NCT02125461) established consolidation durvalumab as standard of care for patients with unresectable, stage III non-small-cell lung cancer (NSCLC) and no disease progression following chemoradiotherapy (CRT). In some cases, patients with stage IIIA-N2 NSCLC are considered operable, but the relative benefit of surgery is unclear. We report a post hoc, exploratory analysis of clinical outcomes in the PACIFIC trial, in patients with or without stage IIIA-N2 NSCLC.

Materials and methods

Patients with unresectable, stage III NSCLC and no disease progression after ≥2 cycles of platinum-based, concurrent CRT were randomized 2 : 1 to receive durvalumab (10 mg/kg intravenously; once every 2 weeks for up to 12 months) or placebo, 1-42 days after CRT. The primary endpoints were progression-free survival (PFS; assessed by blinded independent central review according to RECIST version 1.1) and overall survival (OS). Treatment effects within subgroups were estimated by hazard ratios (HRs) from unstratified Cox proportional hazards models.

Results

Of 713 randomized patients, 287 (40%) had stage IIIA-N2 disease. Baseline characteristics were similar between patients with and without stage IIIA-N2 NSCLC. With a median follow-up of 14.5 months (range: 0.2-29.9 months), PFS was improved with durvalumab versus placebo in both patients with [HR = 0.46; 95% confidence interval (CI), 0.33-0.65] and without (HR = 0.62; 95% CI 0.48-0.80) stage IIIA-N2 disease. Similarly, with a median follow-up of 25.2 months (range: 0.2-43.1 months), OS was improved with durvalumab versus placebo in patients with (HR = 0.56; 95% CI 0.39-0.79) or without (HR = 0.78; 95% CI 0.57-1.06) stage IIIA-N2 disease. Durvalumab had a manageable safety profile irrespective of stage IIIA-N2 status.

Conclusions

Consistent with the intent-to-treat population, treatment benefits with durvalumab were confirmed in patients with stage IIIA-N2, unresectable NSCLC. Prospective studies are needed to determine the optimal treatment approach for patients who are deemed operable.

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The PACIFIC trial established durvalumab after CRT as standard of care for unresectable, stage III NSCLC.

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The optimum multimodal treatment strategy for patients with potentially resectable, stage IIIA-N2 NSCLC is unknown.

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Survival benefit with durvalumab was observed in patients with stage IIIA-N2, unresectable NSCLC in this post hoc analysis.

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Durvalumab after CRT also exhibited a manageable safety profile in this subpopulation from PACIFIC.

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Studies of surgical vs. non-surgical strategies are needed to establish the best approach for potentially operable patients.

Diagnostic accuracy of adenosine deaminase for pleural tuberculosis in a low prevalence setting: A machine learning approach within a 7-year prospective multi-center study

OBJECTIVE

To analyze the performance of adenosine deaminase in pleural fluid combined with other parameters routinely measured in clinical practice and assisted by machine learning algorithms for the diagnosis of pleural tuberculosis in a low prevalence setting, and secondly, to identify effusions that are non-tuberculous and most likely malignant.

PATIENTS AND METHODS

We prospectively analyzed 230 consecutive patients diagnosed with lymphocytic exudative pleural effusion from March 2013 to June 2020. Diagnosis according to the composite reference standard was achieved in all cases. Pre-test probability of pleural tuberculosis was 3.8% throughout the study period. Parameters included were: levels of adenosine deaminase, pH, glucose, proteins, and lactate dehydrogenase, red and white cell counts and lymphocyte percentage in pleural fluid, as well as age. We tested six different machine learning-based classifiers to categorize the patients. Two different classifications were performed: a) tuberculous/non-tuberculous and b) tuberculous/malignant/other.

RESULTS

Out of a total of 230 patients with pleural effusion included in the study, 124 were diagnosed with malignant effusion and 44 with pleural tuberculosis, while 62 were given other diagnoses. In the tuberculous/non-tuberculous classification, and taking into account the validation predictions, the support vector machine yielded the best result: an AUC of 0.98, accuracy of 97%, sensitivity of 91%, and specificity of 98%, whilst in the tuberculous/malignant/other classification, this type of classifier yielded an overall accuracy of 80%. With this three-class classifier, the same sensitivity and specificity was achieved in the tuberculous/other classification, but it also allowed the correct classification of 90% of malignant cases.

CONCLUSION

The level of adenosine deaminase in pleural fluid together with cell count, other routine biochemical parameters and age, combined with a machine-learning approach, is suitable for the diagnosis of pleural tuberculosis in a low prevalence scenario. Secondly, non-tuberculous effusions that are suspected to be malignant may also be identified with adequate accuracy.

Using the Flipped Classroom Model in Surgical Education: Efficacy and Trainee Perception

OBJECTIVE

To describe the feasibility, efficacy, and learner perception of the flipped classroom model for teaching conferences within surgical training programs.

DESIGN

For the flipped classroom conferences, video lectures were prepared by a faculty member, and sent to all attendees at least 2 days prior to lecture. The conference time was then spent going over cases and questions, rather than traditional lecture. We conducted a qualitative survey to assess learner's perceptions and pre-lecture quizzes to assess trainee preparedness.

SETTING

The comparison of pre-conference quizzes between flipped classroom and traditional models was carried out at Brooke Army Medical Center (BAMC) in San Antonio, TX, a tertiary care facility with a general surgery residency program. The survey was conducted at BAMC and within the Complex General Surgical Oncology fellowship program at University of Texas MD Anderson Cancer Center, where a flipped classroom model was similarly employed.

PARTICIPANTS

Surgical residents BAMC participated in pre-lecture quizzes. BAMC residents and MD Anderson fellows were invited to complete the online survey.

RESULTS

Lecture videos did not increase mean preparation time (1.53 vs. 1.46 hours without vs. with video, p = 0.858), but did increase mean quiz scores from 67% to 80% (p = 0.031) with 32/35 learners utilizing videos. Videos increased the proportion of learners who self-reported preparing at all from 42% to 95% (p = 0.28), and preparing for at least one hour for conference from 23% to 49% (p = 0.014). Of survey respondents, 90% said videos were very helpful, 90% would use them weekly if available, and 90% prefer this format to traditional lecture.

CONCLUSIONS

Utilization of a flipped classroom method was well received and preferred by surgical trainees, and it increased performance on pre-conference quizzes without increasing preparation time. Although creation of video lectures is work-intensive for lecturers, these results suggest it is more effective for learner preparation. These results could be generalizable to surgical residents nationwide as technology utilization increases in surgical education.

Haemophilus influenzae Type a Sequence Type 23, Northern Spain

Two consecutive cases of Haemophilus influenzae type a sequence type 23 invasive infection in 2 children attending the same daycare in 2019 triggered epidemiologic surveillance of H. influenzae infections in northern Spain. Despite the invasiveness potential of this virus strain, we detected no additional cases for 2013–2020.

SEOM clinical guidelines for the treatment of malignant pleural mesothelioma (2020)

Mesothelioma is a rare and aggressive tumour with dismal prognosis arising in the pleura and associated with asbestos exposure. Its incidence is on the rise worldwide. In selected patients with early-stage MPM, a maximal surgical cytoreduction in combination with additional antitumour treatment may be considered in selected patients assessed by a multidisciplinary tumor board. In patients with unresectable or advanced MPM, chemotherapy with platinum plus pemetrexed is the standard of care. Currently, no standard salvage therapy has been approved yet, but second-line chemotherapy with vinorelbine or gemcitabine is commonly used. Novel therapeutic approaches based on dual immunotherapy or chemotherapy plus immunotherapy demonstrated promising survival benefit and will probably be incorporated in the future.

Second-line nivolumab in relapsed small-cell lung cancer: CheckMate 331☆

BACKGROUND

Patients with relapsed small-cell lung cancer (SCLC) have few treatment options and dismal survival. Phase I/II data show activity of nivolumab in previously treated SCLC.

PATIENTS AND METHODS

CheckMate 331 is a randomized, open-label, phase III trial of nivolumab versus standard chemotherapy in relapsed SCLC. Patients with relapse after first-line, platinum-based chemotherapy were randomized 1 : 1 to nivolumab 240 mg every 2 weeks or chemotherapy (topotecan or amrubicin) until progression or unacceptable toxicity. Primary endpoint was overall survival (OS).

RESULTS

Overall, 284 patients were randomized to nivolumab and 285 to chemotherapy. Minimum follow-up was 15.8 months. No significant improvement in OS was seen with nivolumab versus chemotherapy [median OS, 7.5 versus 8.4 months; hazard ratio (HR), 0.86; 95% confidence interval (CI), 0.72-1.04; P = 0.11]. A survival benefit with nivolumab was suggested in patients with baseline lactate dehydrogenase ≤ upper limit of normal and in those without baseline liver metastases. OS (nivolumab versus chemotherapy) was similar in patients with programmed death-ligand 1 combined positive score ≥1% versus <1%. Median progression-free survival was 1.4 versus 3.8 months (HR, 1.41; 95% CI, 1.18-1.69). Objective response rate was 13.7% versus 16.5% (odds ratio, 0.80; 95% CI, 0.50-1.27); median duration of response was 8.3 versus 4.5 months. Rates of grade 3 or 4 treatment-related adverse events were 13.8% versus 73.2%.

CONCLUSION

Nivolumab did not improve survival versus chemotherapy in relapsed SCLC. No new safety signals were seen. In exploratory analyses, select baseline characteristics were associated with improved OS for nivolumab.

Measurement of Portal Vein Blood Circulating Tumor Cells is Safe and May Correlate With Outcomes in Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

This study investigated the safety and feasibility of intraoperative portal vein blood (PVB) collection at the time of pancreatic ductal adenocarcinoma (PDAC) resection. Relationships of circulating tumor cells (CTCs) in PVB and peripheral blood (PB) with overall survival (OS) and recurrence-free survival were studied.

METHODS

Patients undergoing PDAC resection were offered enrollment in a prospective liquid biopsy protocol. The patients had PB drawn before incision and PVB drawn before tumor mobilization, then again immediately after resection. Using standard CellSearch protocols, CTCs were identified and compared with OS.

RESULTS

Of the 34 patients enrolled in this study, 23 (68%) underwent pancreaticoduodenectomy, 8 (23%) underwent distal pancreatectomy, and 3 (9%) underwent total pancreatectomy. Peripheral blood was available for 22 (65%) and PVB for 31 (91%) of the patients. No bleeding or thrombotic complications occurred with the PVB draws. The CTC counts per 7.5 mL of PVB collected before and after resection were highly correlated (R² = 0.89). The study found CTCs in 11 (50%) of 22 PB samples and 22 (71%) of 31 PVB samples. The OS rate at 18 months was 92% for the patients with < 3 CTCs, 71% for the patients with ≥ 3 CTCs per 7.5 mL of PB (p = 0.30), 100% for the patients without PVB CTCs, and 70% for the patients with PVB CTCs (p < 0.01).

CONCLUSIONS

Collection of PVB during PDAC resection is safe. In this pilot study, PVB CTC counts but not PB CTC counts were significantly correlated with OS. This opens the door for future studies on selective omission of adjuvant chemotherapy for patients treated preoperatively and tailored surveillance intensity for patients without PVB CTCs at PDAC resection.

Genomic Virulence Features of Two Novel Species Nocardia barduliensis sp. nov. and Nocardia gipuzkoensis sp. nov., Isolated from Patients with Chronic Pulmonary Diseases

Strains 335427^T and 234509^T, isolated from two 76-year-old patients with chronic pulmonary diseases, were the subject of polyphasic taxonomic studies and comparative genomic analyses for virulence factors. The 16 rRNA gene sequence similarity between strains 335427^T and 234509^T and their closest phylogenetic neighbors Nocardia asiatica NBRC 100129^T and Nocardia abscessus NBRC 100374^T were 99.5% and 100%, respectively. Digital DNA-DNA hybridization values between the aforementioned studied strains were well below the 70% threshold for assigning prokaryotic strains to a novel species. Strains 335427^T and 234509^T have genome sizes of 8.49 Mpb and 8.07 Mpb, respectively, with G + C content of 68.5%. Isolate 335427^T has C_16:0, C_18:1 ω₉c, C_18:0 and C_18:0 10 methyl as major fatty acids (>15%) and mycolic acids formed of 52-54 carbon atoms. However, only C_18:1 ω₉c was detected for isolate 234509^T, which had mycolic acids with 44-56 carbon. Based on phenotypic and genetic data, strains 335427^T (DSM 109819^T = CECT 9924^T) and 234509^T (DSM 111366^T = CECT 30129^T) merit recognition as novel species, which are named Nocardia barduliensis sp. nov. and Nocardia gipuzkoensis sp. nov., respectively. All the strains studied had homologous VF-associated genes to those described in M. tuberculosis, including experimentally verified virulence genes in humans related to tuberculosis. The narGHIJ (nitrate reduction pathway) and gvpAFGOJLMK (gas vesicles) genetic maps of strains 335427^T, 234509^T, NBRC 100129^T and NBRC 100374^T showed the same syntenic block and raise the question of whether their functions are interlinked during the infection of the human host. However, further research is required to decipher the role of the gas vesicle in the pathogenicity mechanism of Nocardia spp.

Abstract 2221: Combining irreversible electroporation with TLR7 and CD40 agonists confers systemic anti-tumor immunity in a murine pancreatic cancer model

Introduction: Pancreatic Cancer (PC) has a highly immunosuppressive microenvironment with a low mutational burden and has so far been resistant to immunotherapy. Irreversible electroporation (IRE) is a non-thermal method of inducing tumor cell death, without damage to adjacent blood vessels, that is being used clinically for selected patients with locally advanced PC. Despite local control rates greater than 90%, most IRE patients develop distant recurrence, emphasizing the need for better methods to treat micrometastatic disease. Using an immunocompetent mouse model of PC, we have previously shown that IRE induces complete regression in 25-33% of subcutaneous tumors, and complete responders are protected from a tumor rechallenge. However, IRE alone did not produce significant therapeutic immunity (abscopal effects) against concomitant distant tumors. We hypothesized that combination of IRE with innate immune stimulators would also enhance the adaptive immune response.

Methods: We used a cell line generated from a genetically engineered (KPC) mouse establish bilateral flank tumors. The “primary” tumor was treated with IRE alone or in combination with local delivery of a toll-like receptor 7 (TLR7) agonist (1V270) and CD40 agonistic antibody (CD40Ab). 15 parameter procartaplex (Thermo) was used for cytokine analysis and RNA-Seq was performed using an Illumina MiSeq 1000 platform with total RNA from excised tumor all on day 7 post procedure.

Results: We observed complete regression in 8/10 tumors treated with the combination (Combo) of IRE, 1V270 and CD40Ab compared to 3/10 in IRE alone. However, the combo was much more effective than IRE alone at inducing regression of the untreated secondary flank tumor, including complete regression of 7/10 untreated tumors. CD40Ab alone had minimal effect on local or secondary tumor growth. Analysis of systemic cytokines using multiplex analysis showed 112 fold increase in IFNy levels in plasma with the Combo compared to untreated mice (P&lt;0.001) and a 39 fold increase compared to IRE alone (P&lt;0.001). Other factors of Th1 response such as IP-10 and IL12-P70 were also significantly (P&lt;0.001) higher in the Combo group compared to IRE alone along with TNFa (elevated 3.2 fold vs IRE). RNA-Seq of the whole tumor followed by gene set enrichment analysis showed significant elevation in Type II interferon, (P&lt;0.0001), IL2 (P&lt;0.0001), and apoptosis (P=0.0001) pathways in the Combo group. Both IRE alone and the Combo group complete responders were protected from tumor growth after immediate rechallenge (14 days) and delayed rechallenge (180 days). However, flow cytometric analysis of the splenocytes revealed that the combo group had more CD44+CD62L+CD8+ central memory T-cells (16%) in contrast to IRE alone (11%).

Conclusion: These data suggest that local delivery of CD40Ab and TLR7 agonists augment the systemic immune effects of IRE and have the potential to improve the overall survival of patients undergoing IRE for locally advanced PC by reducing distant recurrence.

Citation Format: Jayanth Surya Narayanan Shankara Narayanan, Diego Vicente, Partha Ray, Thomas Whisenant, Rebekah White. Combining irreversible electroporation with TLR7 and CD40 agonists confers systemic anti-tumor immunity in a murine pancreatic cancer model [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2221.

Outcomes with durvalumab by tumour PD-L1 expression in unresectable, stage III non-small-cell lung cancer in the PACIFIC trial

BACKGROUND

In the PACIFIC trial, durvalumab significantly improved progression-free and overall survival (PFS/OS) versus placebo, with manageable safety, in unresectable, stage III non-small-cell lung cancer (NSCLC) patients without progression after chemoradiotherapy (CRT). We report exploratory analyses of outcomes by tumour cell (TC) programmed death-ligand 1 (PD-L1) expression.

PATIENTS AND METHODS

Patients were randomly assigned (2:1) to intravenous durvalumab 10 mg/kg every 2 weeks or placebo ≤12 months, stratified by age, sex, and smoking history, but not PD-L1 status. Where available, pre-CRT samples were tested for PD-L1 expression (immunohistochemistry) and scored at pre-specified (25%) and post hoc (1%) TC cut-offs. Treatment-effect hazard ratios (HRs) were estimated from unstratified Cox proportional hazards models (Kaplan-Meier-estimated medians).

RESULTS

In total, 713 patients were randomly assigned, 709 of whom received at least 1 dose of study treatment durvalumab (n = 473) or placebo (n = 236). Some 451 (63%) were PD-L1-assessable: 35%, 65%, 67%, 33%, and 32% had TC ≥25%, <25%, ≥1%, <1%, and 1%-24%, respectively. As of 31 January 2019, median follow-up was 33.3 months. Durvalumab improved PFS versus placebo (primary-analysis data cut-off, 13 February 2017) across all subgroups [HR, 95% confidence interval (CI); medians]: TC ≥25% (0.41, 0.26-0.65; 17.8 versus 3.7 months), <25% (0.59, 0.43-0.82; 16.9 versus 6.9 months), ≥1% (0.46, 0.33-0.64; 17.8 versus 5.6 months), <1% (0.73, 0.48-1.11; 10.7 versus 5.6 months), 1%-24% [0.49, 0.30-0.80; not reached (NR) versus 9.0 months], and unknown (0.59, 0.42-0.83; 14.0 versus 6.4 months). Durvalumab improved OS across most subgroups (31 January 2019 data cut-off; HR, 95% CI; medians): TC ≥ 25% (0.50, 0.30-0.83; NR versus 21.1 months), <25% (0.89, 0.63-1.25; 39.7 versus 37.4 months), ≥1% (0.59, 0.41-0.83; NR versus 29.6 months), 1%-24% (0.67, 0.41-1.10; 43.3 versus 30.5 months), and unknown (0.60, 0.43-0.84; 44.2 versus 23.5 months), but not <1% (1.14, 0.71-1.84; 33.1 versus 45.6 months). Safety was similar across subgroups.

CONCLUSIONS

PFS benefit with durvalumab was observed across all subgroups, and OS benefit across all but TC <1%, for which limitations and wide HR CI preclude robust conclusions.

Comparison of gemcitabine delivery and tumor response in a pressurized pancreatic retrograde venous infusion versus systemic infusion in an orthotopic murine model

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Background: Pancreatic ductal adenocarcinoma (PDAC) is associated with limited response to systemic therapy (ST). Elevated tumor interstitial fluid pressures (IFP) inhibit penetration of ST. Regional Pressure Enabled Drug Delivery has recently demonstrated improved response for liver tumors in a clinical trial. However, this delivery method has not been evaluated in PDAC. We compared gemcitabine (Gem) by systemic delivery vs. a novel pressurized Pancreatic Retrograde Venous Infusion (PRVI) method in an orthotopic PDAC mouse model. Methods: PDAC murine cell line (KPC4580P) tumors were transplanted onto the pancreatic tail of C57BL/6J mice. Groups of 15 mice were randomly assigned to PRVI Gem, PRVI saline (Control), or intraperitoneal Gem (Systemic) groups. Five mice from the PRVI and Systemic groups were randomly selected after one hour post infusion to evaluate Gem tumor concentrations by liquid chromatography - tandem mass spectrometry (ng/mg), and the remainder of mice were euthanized after 7 days to evaluate treatment response. Results: Tumor concentrations of Gem were significantly higher following PRVI compared to Systemic (128 vs. 19, p < 0.01) at one hour after treatment. Seven days after treatment, PRVI Gem mice demonstrated lower mean tumor volume (mm3) than Systemic Gem and Control mice (274 vs. 857 vs. 629, p < 0.01), respectively. Histologic evaluation of tumors demonstrated decreased cellularity in the PRVI Gem mice compared to Systemic and Control mice (35 vs. 78 vs. 71%, p = 0.01), respectively. No differences were seen in Ki67% or immune cell infiltrate between groups. Conclusions: PRVI delivery resulted in increased PDAC Gem concentrations and improved treatment responses with decreased tumor burden and cellularity. These findings suggest that pressurized regional chemotherapy infusion overcomes the elevated PDAC IFP and justifies additional translational pre-clinical studies with other chemotherapeutics (including immunomodulating antibodies) with different physicochemical properties.

Multiplex profiling of peritoneal metastases from gastric adenocarcinoma identified novel targets and molecular subtypes that predict treatment response

OBJECTIVE

Peritoneal carcinomatosis (PC) occurs frequently in patients with gastric adenocarcinoma (GAC) and confers a poor prognosis. Multiplex profiling of primary GACs has been insightful but the underpinnings of PC's development/progression remain largely unknown. We characterised exome/transcriptome/immune landscapes of PC cells from patients with GAC aiming to identify novel therapeutic targets.

DESIGN

We performed whole-exome sequencing (WES) and whole transcriptome sequencing (RNA-seq) on 44 PC specimens (43 patients with PC) including an integrative analysis of WES, RNA-seq, immune profile, clinical and pathological phenotypes to dissect the molecular pathogenesis, identifying actionable targets and/or biomarkers and comparison with TCGA primary GACs.

RESULTS

We identified distinct alterations in PC versus primary GACs, such as more frequent CDH1 and TAF1 mutations, 6q loss and chr19 gain. Alterations associated with aggressive PC phenotypes emerged with increased mutations in TP53, CDH1, TAF1 and KMT2C, higher level of 'clock-like' mutational signature, increase in whole-genome doublings, chromosomal instability (particularly, copy number losses), reprogrammed microenvironment, enriched cell cycle pathways, MYC activation and impaired immune response. Integrated analysis identified two main molecular subtypes: 'mesenchymal-like' and 'epithelial-like' with discriminating response to chemotherapy (31% vs 71%). Patients with the less responsive 'mesenchymal-like' subtype had high expression of immune checkpoint T-Cell Immunoglobulin And Mucin Domain-Containing Protein 3 (TIM-3), its ligand galectin-9, V-domain Ig suppressor of T cell activation (VISTA) and transforming growth factor-β as potential therapeutic immune targets.

CONCLUSIONS

We have uncovered the unique mutational landscape, copy number alteration and gene expression profile of PC cells and defined PC molecular subtypes, which correlated with PC therapy resistance/response. Novel targets and immune checkpoint proteins have been identified with a potential to be translated into clinics.

Fatal Case of Nosocomial Legionella pneumophila Pneumonia, Spain, 2018

A nosocomial case of Legionella pneumophila pneumonia likely caused by a serogroup 3 strain was detected by a urinary antigen test in Spain in 2018. Although Legionella bacteria could not be isolated from respiratory samples, molecular methods implicated the sink faucet of the patient's room as the probable infection source.

Irreversible Electroporation Combined with Checkpoint Blockade and TLR7 Stimulation Induces Antitumor Immunity in a Murine Pancreatic Cancer Model

Irreversible electroporation (IRE) is a nonthermal ablation technique that is used clinically in selected patients with locally advanced pancreatic cancer, but most patients develop recurrent distant metastatic disease. We hypothesize that IRE can induce an in situ vaccination effect by releasing tumor neoantigens in an inflammatory context. Using an immunocompetent mouse model, we demonstrated that IRE alone produced complete regression of subcutaneous tumors in approximately 20% to 30% of mice. IRE was not effective in immunodeficient mice. Mice with complete response to IRE demonstrated prophylactic immunity and remained tumor free when rechallenged with secondary tumors on the contralateral flank. CD8⁺ T cells from IRE-responsive mice were reactive against peptides representing model-inherent alloantigens and conferred protection against tumor challenge when adoptively transferred into immunocompromised, tumor-naïve mice. Combining IRE with intratumoral Toll-like receptor-7 (TLR7) agonist (1V270) and systemic anti-programmed death-1 receptor (PD)-1 checkpoint blockade resulted in improved treatment responses. This combination also resulted in elimination of untreated concomitant distant tumors (abscopal effects), an effect not seen with IRE alone. These results suggest that the systemic antitumor immune response triggered by IRE can be enhanced by stimulating the innate immune system with a TLR7 agonist and the adaptive immune system with anti-PD-1 checkpoint blockade simultaneously. Combinatorial approaches such as this may help overcome the immunosuppressive pancreatic cancer microenvironment.

Human metapneumovirus as cause of severe community-acquired pneumonia in adults: insights from a ten-year molecular and epidemiological analysis

Background

Information on the clinical, epidemiological and molecular characterization of human metapneumovirus in critically ill adult patients with severe community-acquired pneumonia (CAP) and the role of biomarkers identifying bacterial coinfection is scarce.

Methods

This is a retrospective epidemiological study of adult patients with hMPV severe CAP admitted to ICU during a ten-year period with admission PSI score ≥ 3.

Results

The 92.8% of the 28 patients with severe CAP due to human metapneumovirus were detected during the first half of the year. Median age was 62 years and 60.7% were male. The genotyping of isolated human metapneumovirus showed group B predominance (60.7%). All patients had acute respiratory failure. Median APACHE II and SOFA score were 13 and 6.55, respectively. The 25% were coinfected with Streptococcus pneumoniae. 60.7% of the patients had shock at admission and 50% underwent mechanical ventilation. Seven patients developed ARDS, three of them younger than 60 years and without comorbidities. Mortality in ICU was 14.3%. Among survivors, ICU and hospital stay were 6.5 and 14 days, respectively. Plasma levels of procalcitonin were higher in patients with bacterial coinfection (18.2 vs 0.54; p < 0.05). The levels of C-reactive protein, however, were similar.

Conclusion

Human metapneumovirus was associated with severe CAP requiring ICU admission among elderly patients or patients with comorbidities, but also in healthy young subjects. These patients often underwent mechanical ventilation with elevated health resource consumption. While one out of four patients showed pneumococcal coinfection, plasma procalcitonin helped to implement antimicrobial stewardship.

Electronic supplementary material

The online version of this article (10.1186/s13613-019-0559-y) contains supplementary material, which is available to authorized users.

Low antimicrobial resistance rates of Mycobacterium tuberculosis complex between 2000 and 2015 in Gipuzkoa, northern Spain

OBJECTIVE

Although the incidence of tuberculosis (TB) has declined, TB drug resistance remains a major problem. The TB rate in Gipuzkoa (northern Spain) is higher than the European average. The objective of this study was to determine the antimicrobial susceptibility of 1855 Mycobacterium tuberculosis complex isolates (94.5% of confirmed cases between 2000 and 2015).

METHODS

Susceptibility testing was performed using the agar proportion method and a commercial broth system (MGIT 960). In isoniazid- or rifampicin-resistant strains, we studied genetic determinants of drug resistance and genotype (MIRU-VNTR).

RESULTS

The annual mean incidence of TB was 24.5 cases per 100,000 population on average, and tended to decrease. The multidrug-resistant TB rate was 0.5% (9/1855), and no extensively drug-resistant TB strains were detected. Rates of resistance to isoniazid and rifampicin were 3.9% (range, 3.4-4.3%) and 0.6% (range, 0.4-1.4%), respectively. TB resistance was more common among foreign-born individuals and those who had received previous TB treatment. Genotyping of 102 resistant strains showed predominance of the Euro-American lineage, although 4/9 multidrug-resistant strains had Eastern lineages (2 East African-Indian, and 2 East Asian [Beijing]).

CONCLUSIONS

In Gipuzkoa, with a moderate incidence of TB, resistance was very low, mostly being detected among individuals who were born abroad or who had a history of TB treatment.

Utility of MALDI-TOF MS as a new tool for Streptococcus pneumoniae serotyping

Nowadays, more than 95 different Streptococcus pneumoniae serotypes are known, being less than one third responsible for the majority of severe pneumococcal infections. After the introduction of conjugate vaccines, a change in the epidemiology of the serotypes causing invasive pneumococcal disease has been observed making the surveillance of circulating serotypes especially relevant. Some recent studies have used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) technology to identify the most frequent pneumococcal serotypes that cause invasive disease. The objectives of this study were to evaluate the efficacy of previously described discriminatory peaks determined by MALDI-TOF MS for the identification of serotypes 6B, 19F, 19A and 35B using reference and clinical isolates and to try to identify other discriminatory peaks for serotypes 11A, 19F and 19A using transformed pneumococcal strains. Most of the proposed peaks defined in the literature for the identification of serotypes 6B, 19F, 19A, 35B were not found in the spectra of the 10 reference isolates nor in those of the 60 clinical isolates tested corresponding to these four serotypes. The analysis and comparison of the mass spectra of genetically modified pneumococci (transformed strains) did not allow the establishment of new discriminatory peaks for serotypes 11A, 19F, and 19A. MALDI-TOF MS in the usual range of 2,000 to 20,000 m/z did not prove to be a valid technique for direct S. pneumoniae serotyping.

Impact of epidural analgesia on the systemic biomarker response after hepatic resection

Background

Perioperative inflammation is associated with poor oncologic outcomes. Regional analgesia has been shown mitigate some of these inflammatory changes and be associated with better oncologic outcomes in patients with hepatic malignancies. The mechanism for this effect, however, remains unclear. The authors sought to compare systemic biomarker concentrations in a comprehensive and oncologically relevant panel in the perioperative setting between patients undergoing thoracic epidural analgesia (TEA) and intra-venous patient- controlled analgesia (IV-PCA) for resection of hepatic metastatic disease.

Results

Clinicopathologic variables and baseline biomarkers were similar between TEA (n = 46) and IV-PCA (n = 16) groups. Of the biomarkers which were significantly changed from baseline, there was a lower fold change from baseline in the TEA patients compared to IV-PCA including IL-6 (13.5vs19.1), MCP-1 (1.9vs3.0), IL-8 (2.4vs3.0), and Pentraxin-3 (10.8vs15.6). Overall decreased systemic concentrations of TGFb signaling were noted in TEA patients on POD1 TGFb3 (243.2 vs. 86.0, p = 0.005), POD3 TGFb1 (6558.0 vs. 2063.3, p = 0.004), POD3 TGFb2 (468.3 vs. 368.9, p = 0.036), POD3 TGFb3 (132.2 vs. 77.8, p = 0.028), and POD5 TGFb3 (306.5 vs. 92.2, p = 0.032). POD1 IL-12p70 concentrations were significantly higher in TEA patients (8.3 vs. 1.6, p = 0.024).

Conclusion

Epidural analgesia damped the postoperative inflammatory response and systemic immunosuppressive signaling, as well as promoted Th1 systemic signaling early in the post-operative period after hepatic resection for metastatic disease. These differences elaborate on known mechanisms for improved oncologic outcomes with regional anesthesia, and may be considered for biomarker monitoring of effective regional anesthesia in oncologic surgery.

Materials and Methods

Patient data, including clinicopathologic variables were collected for this study from the database of a randomized controlled trial comparing perioperative outcomes in patients undergoing hepatic resection with TEA vs. IV-PCA. Patients undergoing resection for metastatic disease were selected for this study. Plasma concentrations (pg/mL) of well-studied biomarkers (IL-1b/2/4/5/6/7/8/10/12p70/13/17, MCP-1 IFNγ, TNFα, MIP-1b, GM-CSF, G-CSF, VEGF, Resistin, TGFb1, TGFb2, and TGFb3), as well as novel perioperative markers (CXCL12, CXCL10, Omentin-1, sLeptin R, Vaspin, Pentraxin-3, Galactin-3, FGF-23, PON-1, FGF-21) were measured preoperatively, and on postoperative day (POD)1, POD3, and POD5 using multiplex bead assays. Clinicopathologic variables and perioperative variations in these biomarkers were compared between TEA vs IV-PCA groups.

Primary Cutaneous Nocardia brasiliensis in a Spanish Child

BACKGROUND

We report a case of a primary cutaneous nocardiosis by autochthonous Nocardia brasiliensis in a Spanish immunocompetent 9-year-old boy.

METHODS

N. brasiliensis caused cellulitis showing the patient recovery after drainage and treatment with trimethoprim-sulfamethoxazole. Nocardia grew in pure culture and its identification was confirmed by sequencing (16S rRNA) and by MALDI-TOF MS (Bruker, Daltonics, Germany).

CONCLUSIONS

In Spain although N. brasiliensis cutaneous infections in children are very infrequent should not be ruled out when an insect bite, stuck with a pine needle or an animal scratch has existed and the wound evolution is torpid.