1
|
Yang J, Li L, Su W, Zhang S, Xu H, Wang M, Shen W. Microbiomic signatures of anal fistula and putative sources of microbes. Front Cell Infect Microbiol 2024; 14:1332490. [PMID: 38312743 PMCID: PMC10834682 DOI: 10.3389/fcimb.2024.1332490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/02/2024] [Indexed: 02/06/2024] Open
Abstract
Anal fistula is a common perianal disease that typically develops from an abscess caused by in-flammation in the area. It has long been believed that intestinal microbes play a significant role in its development, considering its close relation to the intestinal environment. This work attempts to identify the microbiomic signatures of anal fistula, and putative sources of microbes by analyzing microbiomes of 7 anal fistula-associated sites in 12 patients. This study found that microbes in anal fistulas may originate from the skin surface in addition to the intestinal tract. This finding was further validated by NMDS analysis, which also indicated that the microbial communities in the inner and outer openings of the fistula were more similar to their surrounding environments. Using MaAslin2, the characteristics of the microbiome were examined, demonstrating a higher similarity between the abundant bacteria in the anal fistula samples and those found on the skin surface. Moreover, pin-to-pair analysis conducted on all subjects consistently showed a higher abundance of skin-sourced bacteria in anal fistulas. This study identifies the microbiomic signatures of anal fistula, and provides novel insights into the origin of microorganisms in anal fistulas.
Collapse
Affiliation(s)
- Jun Yang
- Department of Anorectal Surgery, Qilu Hospital of Shandong University (Qingdao), Qingdao, Shandong, China
| | - Ling Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Wenya Su
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Shuqin Zhang
- Department of Anorectal Surgery, Yinan Hospital of Traditional Chinese Medicine, Linyi, Shandong, China
| | - Hai Xu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Mingyu Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Wenlong Shen
- Department of Anorectal Surgery, Qilu Hospital of Shandong University (Qingdao), Qingdao, Shandong, China
| |
Collapse
|
2
|
Anandabaskaran S, Hanna L, Iqbal N, Constable L, Tozer P, Hart A. Where Are We and Where to Next?-The Future of Perianal Crohn's Disease Management. J Clin Med 2023; 12:6379. [PMID: 37835022 PMCID: PMC10573672 DOI: 10.3390/jcm12196379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
Perianal fistulizing Crohn's Disease (pCD) affects about 25% of patients with Crohn's Disease (CD). It remains a difficult entity to manage with a therapeutic ceiling of treatment success despite improving medical and surgical management. The refractory nature of the disease calls for an imminent need to better understand its immunopathogenesis and classification to better streamline our treatment options. In this article, we overview the current state of pCD management and discuss where the future of its management may lie.
Collapse
Affiliation(s)
- Sulak Anandabaskaran
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, UK
- Robin Phillip’s Fistula Research Unit, St Mark’s Hospital and Academic Institute, London HA1 3UJ, UK
- Faculty of Medicine, St Vincent’s Clinical School, University of New South Wales, 390 Victoria Street, Darlinghurst, NSW 2010, Australia
| | - Luke Hanna
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, UK
- Robin Phillip’s Fistula Research Unit, St Mark’s Hospital and Academic Institute, London HA1 3UJ, UK
| | - Nusrat Iqbal
- Robin Phillip’s Fistula Research Unit, St Mark’s Hospital and Academic Institute, London HA1 3UJ, UK
- Department of Surgery and Cancer, South Kensington Campus, Imperial College London, London SW7 2BX, UK
| | - Laura Constable
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, UK
| | - Phil Tozer
- Robin Phillip’s Fistula Research Unit, St Mark’s Hospital and Academic Institute, London HA1 3UJ, UK
- Department of Surgery and Cancer, South Kensington Campus, Imperial College London, London SW7 2BX, UK
| | - Ailsa Hart
- Robin Phillip’s Fistula Research Unit, St Mark’s Hospital and Academic Institute, London HA1 3UJ, UK
- Department of Surgery and Cancer, South Kensington Campus, Imperial College London, London SW7 2BX, UK
| |
Collapse
|
3
|
Singh A, Midha V, Kochhar GS, Shen B, Sood A. Management of Perianal Fistulizing Crohn's Disease. Inflamm Bowel Dis 2023:izad195. [PMID: 37672347 DOI: 10.1093/ibd/izad195] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Indexed: 09/08/2023]
Abstract
Perianal fistulizing Crohn's disease (CD) represents a severe phenotype of CD that is associated with significant morbidity and reduction in quality of life. Perianal fistulizing CD is caused by a complex interplay of genetic predisposition, immune dysregulation, gut dysbiosis, and various unknown physiological and mechanical factors. A multidisciplinary approach is hence required for optimal management . A detailed anatomical description and classification of perianal fistula, including comprehensive clinical, endoscopic, and radiological diagnostic workup, is an important prerequisite to treatment. For simple perianal fistulas, use of antibiotics and immunomodulators, with or without fistulotomy, are appropriate measures. The medical management of complex perianal fistula, on the other hand, requires adequate control of infection before initiation of therapy with immunomodulators. In active complex perianal fistula, anti-tumor necrosis factors remain the most accepted therapy, with concomitant use of antibiotics or immunomodulators enhancing the efficacy. For patients refractory to anti-tumor necrosis factors, treatment with anti-integrins, anti-interleukins, and small molecules is being evaluated. Mesenchymal stem cells, hyperbaric oxygen therapy, and exclusive enteral nutrition have also been investigated as adjunct therapies. Despite the expansion of the medical armamentarium, a large proportion of the patients require surgical interventions. In this review, we provide an up-to-date overview of the pathophysiology, clinical presentation, diagnosis, and medical management of perianal fistulizing CD. A brief overview of the surgical management of perianal fistulizing CD is also provided.
Collapse
Affiliation(s)
- Arshdeep Singh
- Department of Gastroenterology, Dayanand Medical College, Ludhiana, India
| | - Vandana Midha
- Department of Internal Medicine, Dayanand Medical College, Ludhiana, India
| | - Gursimran Singh Kochhar
- Division of Gastroenterology, Hepatology and Nutrition, Allegheny Health Network, Pittsburgh, PA, USA
| | - Bo Shen
- Center for Interventional Inflammatory Bowel Disease, NewYork-Presbyterian Hospital, Columbia University Irving Medical Center, New York, NY, USA
| | - Ajit Sood
- Department of Gastroenterology, Dayanand Medical College, Ludhiana, India
| |
Collapse
|
4
|
Autologous adipose-derived stromal vascular fraction and platelet concentrates for the treatment of complex perianal fistulas. Tech Coloproctol 2023; 27:135-143. [PMID: 36063257 PMCID: PMC9839808 DOI: 10.1007/s10151-022-02675-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 07/27/2022] [Indexed: 01/18/2023]
Abstract
BACKGROUND Complex perianal fistulas are a major challenge for modern surgery since 10-35% of patients have functional problems after treatment. Sphincter-saving techniques have a wide range of efficacy (10-80%). We hypothesised that autologous adipose-derived stromal vascular fraction in combination with platelet rich plasma is a new therapeutic strategy with enhanced cure and function preservation rates. METHODS Adult patients with complex cryptoglandular perianal fistulas were treated with injection of autologous adipose-derived stromal vascular fraction in combination with platelet rich plasma around and inside the fistulous tract between May 2018 and April 2019 at the General and Emergency Surgery Operative Unit of the University Hospital "P. Giaccone" of Palermo. Fistulas were confirmed by magnetic resonance imaging. Patients completed the Short Form-36 score on quality of life and the Wexner and Vaizey scores on faecal incontinence, and they were functionally studied using a three-dimensional anorectal manometry. The clinical and functional follow-up was performed at 1 year and 2 years after surgery. RESULTS Nine patients (4 males, 5 females; median age 42 years [19-63 years]) with high trans-sphincteric or horseshoe fistulas were treated. The average number of previous surgeries per patient was 4.8. At 1 year follow-up, 77.7% of patients were cured, while at 2 years there was 1case of relapse. The variation in Short Form-36 score in cured patients was not significant (p = 0.0936). No statistically significant differences were found in continence scores. CONCLUSIONS The proposed treatment is a treatment option that preserves sphincter integrity and function, potentially avoiding postoperative incontinence and the need of repeated treatments.
Collapse
|
5
|
Litta F, Papait A, Lucchetti D, Farigu S, Parello A, Tenore CR, Campennì P, Silini AR, Giustiniani MC, Parolini O, Sgambato A, Ratto C. The pathogenesis of cryptoglandular anal fistula: New insight into the immunological profile. Colorectal Dis 2022; 24:1567-1575. [PMID: 35916639 PMCID: PMC10087133 DOI: 10.1111/codi.16290] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 07/08/2022] [Accepted: 07/27/2022] [Indexed: 01/07/2023]
Abstract
AIM The aetiology of cryptoglandular anal fistula (AF) is poorly understood. Evidence suggests that persistence and/or recurrence of the disease is more related to inflammatory than infectious factors. The aim of this study was to investigate the immune profile of cryptoglandular AF and to perform a histopathological characterization. METHOD Fistulectomy was performed in all patients; healthy ischioanal fat from the same patients was used as a control. Samples were evaluated by the Luminex xMAP system for the detection of 27 analytes. AF tissues were analysed using immunofluorescence. Staining was performed using primary antibodies to identify M1 inflammatory and M2 anti-inflammatory macrophages. Selective staining of total T lymphocytes and different T lymphocyte subsets was performed. RESULTS Twenty patients with AF underwent a fistulectomy. Specific cytokine pathways differentiated AF from healthy tissue: pro-inflammatory cytokines interleukin (IL)-1β, IL-4, IL-8 and IL-17 and the anti-inflammatory cytokine IL-10 were overexpressed in AF compared with controls. Chemokines involved in macrophage recruitment (CCL2, CCL3, CCL4) were higher in AF than in healthy fatty tissue. Moreover, we showed that Tc17 cells characterize AF patients, thus confirming the enzyme-linked immunosorbent assay data. Furthermore, elevated infiltration of CD68+ myeloid cells and a reduction of the M1/M2 ratio characterize AF patients. CONCLUSION A combination of inflammatory cytokines, chemokines and growth factors reside in the wound microenvironment of AF patients. For the first time an important prevalence of Tc17 cells and a reduction in the M1/M2 ratio was observed, thus suggesting new insights into the immunological characterization of AF patients.
Collapse
Affiliation(s)
- Francesco Litta
- Proctology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Andrea Papait
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario 'Agostino Gemelli' IRCCS, Rome, Italy
| | - Donatella Lucchetti
- Dipartimento Universitario di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Serafina Farigu
- Centro di Ricerca E. Menni, Fondazione Poliambulanza, Brescia, Italy
| | - Angelo Parello
- Proctology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Claudio Ricciardi Tenore
- Dipartimento Universitario di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Paola Campennì
- Proctology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | | | | | - Ornella Parolini
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario 'Agostino Gemelli' IRCCS, Rome, Italy
| | - Alessandro Sgambato
- Dipartimento Universitario di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Carlo Ratto
- Proctology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| |
Collapse
|
6
|
Pathogenesis of Fistulating Crohn's Disease: A Review. Cell Mol Gastroenterol Hepatol 2022; 15:1-11. [PMID: 36184031 PMCID: PMC9667304 DOI: 10.1016/j.jcmgh.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/20/2022] [Accepted: 09/20/2022] [Indexed: 12/10/2022]
Abstract
Sustained, transmural inflammation of the bowel wall may result in the development of a fistula in Crohn's disease (CD). Fistula formation is a recognized complication and cause of morbidity, occurring in 40% of patients with CD. Despite advanced treatment, one-third of patients experience recurrent fistulae. Development of targeting treatment for fistulae will be dependent on a more in depth understanding of its pathogenesis. Presently, pathogenesis of CD-associated fistulae remains poorly defined, in part due to the lack of accepted in vitro tissue models recapitulating the pathogenic cellular lesions linked to fistulae and limited in vivo models. This review provides a synthesis of the existing knowledge of the histopathological, immune, cellular, genetic, and microbial contributions to the pathogenesis of CD-associated fistulae including the widely accredited contribution of epithelial-to-mesenchymal transition, upregulation of matrix metalloproteinases, and overexpression of invasive molecules, resulting in tissue remodeling and subsequent fistula formation. We conclude by exploring how we might utilize advancing technologies to verify and broaden our current understanding while exploring novel causal pathways to provide further inroads to future therapeutic targets.
Collapse
|
7
|
Chin Koon Siw K, Engel J, Visva S, Mallick R, Hart A, de Buck van Overstraeten A, McCurdy JD. Strategies to Distinguish Perianal Fistulas Related to Crohn's Disease From Cryptoglandular Disease: Systematic Review With Meta-Analysis. Inflamm Bowel Dis 2022; 28:1363-1374. [PMID: 34792583 DOI: 10.1093/ibd/izab286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Indexed: 12/09/2022]
Abstract
BACKGROUND Management of perianal fistulas differs based on fistula type. We aimed to assess the ability of diagnostic strategies to differentiate between Crohn's disease (CD) and cryptoglandular disease (CGD) in patients with perianal fistulas. METHODS We performed a diagnostic accuracy systematic review and meta-analysis. A systematic search of electronic databases was performed from inception through February 2021 for studies assessing a diagnostic test's ability to distinguish fistula types. We calculated weighted summary estimates with 95% confidence intervals for sensitivity and specificity by bivariate analysis, using fixed effects models when data were available from 2 or more studies. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess study quality. RESULTS Twenty-one studies were identified and included clinical symptoms (2 studies; n=154), magnetic resonance imaging (MRI) characteristics (3 studies; n=296), ultrasound characteristics (7 studies; n=1003), video capsule endoscopy (2 studies; n=44), fecal calprotectin (1 study; n=56), and various biomarkers (8 studies; n=440). MRI and ultrasound characteristics had the most robust data. Rectal inflammation, multiple-branched fistula tracts, and abscesses on pelvic MRI and the Crohn's ultrasound fistula sign, fistula debris, and bifurcated fistulas on pelvic ultrasonography had high specificity (range, 80%-95% vs 89%-96%) but poor sensitivity (range, 17%-37% vs 31%-63%), respectively. Fourteen of 21 studies had risk of bias on at least 1 of the Quality Assessment of Diagnostic Accuracy Studies domains. CONCLUSIONS Limited high-quality evidence suggest that imaging characteristics may help discriminate CD from CGD in patients with perianal fistulas. Larger, prospective studies are needed to confirm these findings and to evaluate if combining multiple diagnostic tests can improve diagnostic sensitivity.
Collapse
Affiliation(s)
- Kevin Chin Koon Siw
- Division of Gastroenterology and Hepatology, University of Ottawa, Ottawa, ON, Canada
| | - Jake Engel
- Faculty of Medicine, University of Ottawa, ON, Canada
| | | | | | - Ailsa Hart
- Division of Gastroenterology, St Mark's Hospital, London, United Kingdomand the
| | | | - Jeffrey D McCurdy
- Division of Gastroenterology and Hepatology, University of Ottawa, Ottawa, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada
| |
Collapse
|
8
|
Breton J, Tanes C, Tu V, Albenberg L, Rowley S, Devas N, Hwang R, Kachelries K, Wu GD, Baldassano RN, Bittinger K, Mattei P. A Microbial Signature for Paediatric Perianal Crohn's Disease. J Crohns Colitis 2022; 16:1281-1292. [PMID: 35211723 DOI: 10.1093/ecco-jcc/jjac032] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/09/2021] [Accepted: 02/23/2022] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIMS Perianal fistulising disease can affect up to 25% of patients with Crohn's disease [CD] and lead to significant morbidity. Although the role of the gut microbiota in inflammatory bowel disease [IBD] has been increasingly recognised, its role in fistula development has scarcely been studied. Here, we aimed to define the microbial signature associated with perianal fistulising CD in children. METHODS A prospective observational study including children age 6-18 years with a diagnosis of perianal fistulising CD was conducted. Stool samples and rectal and perianal fistula swabs were collected. Stool samples and rectal swabs from children with CD without perianal disease and healthy children were included as comparison. Whole shotgun metagenomic sequencing was performed. RESULTS A total of 31 children [mean age 15.5 ± 3.5 years] with perianal CD were prospectively enrolled. The fistula-associated microbiome showed an increase in alpha diversity and alteration in the abundance of several taxa compared with the rectal- and faecal-associated microbiome with key taxa belonging to the Proteobacteria phylum. Genes conferring resistance to the clinically used antibiotic regimen ciprofloxacin and metronidazole were found in the three sample types. In comparison with children without the perianal phenotype [N = 36] and healthy controls [N = 41], the mucosally-associated microbiome of children with perianal CD harboured a reduced butyrogenic potential. Linear discriminant analysis identified key taxa distinguishing the rectal mucosally-associated microbiome of children with perianal CD from children without this phenotype. CONCLUSIONS The microbial community within CD-related anorectal fistula is compositionally and functionally unique. Taken together, these findings emphasise the need to better understand the ecosystem of the fistula milieu to guide development of novel microbiome-based strategies in this CD phenotype.
Collapse
Affiliation(s)
- Jessica Breton
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ceylan Tanes
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Vincent Tu
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Lindsey Albenberg
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sarah Rowley
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Nina Devas
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Rosa Hwang
- Division of General Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kelly Kachelries
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Gary D Wu
- Division of Gastroenterology and Hepatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert N Baldassano
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kyle Bittinger
- Division of Gastroenterology, Hepatology, and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Peter Mattei
- Division of General Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| |
Collapse
|
9
|
Ratto C, Parolini O, Marra AA, Orticelli V, Parello A, Campennì P, De Simone V, Trojan D, Litta F. Human Amniotic Membrane for the Treatment of Cryptoglandular Anal Fistulas. J Clin Med 2022; 11:jcm11051350. [PMID: 35268442 PMCID: PMC8911009 DOI: 10.3390/jcm11051350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 02/25/2022] [Accepted: 02/27/2022] [Indexed: 12/19/2022] Open
Abstract
Background: Implantation of the amniotic membrane and their derivatives can have a beneficial effect on tissue repair and regeneration. We report for the first time the implant of an amniotic membrane in a patient affected by cryptoglandular anal fistula. Methods: A patch of human amniotic membrane was implanted in a female patient affected by an anterior transphincteric fistula. Following an accurate curettage of the anal fistula, the cryopreserved amniotic membrane was thawed and then washed in the operating room; one side of the membrane was transfixed with a resorbable suture thus creating an implantable fusiform patch. The membrane was subsequently implanted into the fistula tract from the external to the internal opening. The inner and outer parts of the membrane were then sutured to the internal and external fistula openings. Results: No intraoperative or postoperative complications occurred. The patient was discharged one day after the procedure after an uneventful hospitalization. At the 1-week, 1- and 3-month follow-up visits no pain (VAS 0) was referred by the patient and no inflammation was evident at the level of the previous external fistula opening. Conclusions: The implant of human amniotic membrane in a patient affected by cryptoglandular anal fistula was safely and easily performed. Moreover, future studies to assess the efficacy in the long-term follow-up are needed.
Collapse
Affiliation(s)
- Carlo Ratto
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
- Department of Medicine and Translational Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Correspondence: ; Tel.: +39-3356886968
| | - Ornella Parolini
- Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (O.P.); (V.O.)
- Department of Life Science and Public Health, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Angelo Alessandro Marra
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
| | - Valentina Orticelli
- Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (O.P.); (V.O.)
| | - Angelo Parello
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
| | - Paola Campennì
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
| | - Veronica De Simone
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
| | - Diletta Trojan
- Tissue Bank, Fondazione Banca Dei Tessuti Di Treviso Onlus, 31100 Treviso, Italy;
| | - Francesco Litta
- Proctology Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; (A.A.M.); (A.P.); (P.C.); (V.D.S.); (F.L.)
| |
Collapse
|
10
|
Adegbola SO, Sarafian M, Sahnan K, Ding NS, Faiz OD, Warusavitarne J, Phillips RKS, Tozer PJ, Holmes E, Hart AL. Differences in amino acid and lipid metabolism distinguish Crohn's from idiopathic/cryptoglandular perianal fistulas by tissue metabonomic profiling and may offer clues to underlying pathogenesis. Eur J Gastroenterol Hepatol 2021; 33:1469-1479. [PMID: 33337668 DOI: 10.1097/meg.0000000000001976] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Few studies have investigated perianal fistula etiopathogenesis, and although the cryptoglandular theory is widely accepted in idiopathic cases, in Crohn's disease, it is thought to involve the interplay between microbiological, immunological and genetic factors. A pilot study was conducted to assess for metabolic variations in Crohn's perianal fistula tissue that might differ from that of idiopathic (cryptoglandular) perianal fistula tissue as a comparator. The goal was to identify any potential biomarkers of disease, which may improve the understanding of pathogenesis. AIMS AND METHODS Fistula tract biopsies were obtained from 30 patients with idiopathic perianal fistula and 20 patients with Crohn's anal fistula. Two different assays were used in an ultra-high-performance liquid chromatography system coupled with a mass spectrometric detector to achieve broad metabolome coverage. Univariate and multivariate statistical data analyses were used to identify differentiating metabolic features corresponding to the perianal fistula phenotype (i.e. Crohn's disease vs. idiopathic). RESULTS Significant orthogonal partial least squares discriminant analysis predictive models (validated with cross-validated-analysis of variance P value <0.05) differentiated metabolites from tissue samples from Crohn's vs. idiopathic anal fistula patients using both metabolic profiling platforms. A total of 41 metabolites were identified, suggesting alterations in pathways, including amino acid, carnitine and lipid metabolism. CONCLUSION Metabonomics may reveal biomarkers of Crohn's perianal fistula. Further work in larger numbers is required to validate the findings of these studies as well as cross-correlation with microbiome work to better understand the impact of host-gut/environment interactions in the pathophysiology of Crohn's and idiopathic perianal fistulas and identify novel therapeutic targets.
Collapse
Affiliation(s)
- Samuel O Adegbola
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Magali Sarafian
- Computational Systems Division, Imperial College London, South Kensington Campus, London, UK
| | - Kapil Sahnan
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Nik S Ding
- Department of Gastroenterology, St Vincent's Hospital, Melbourne, Australia
| | - Omar D Faiz
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Janindra Warusavitarne
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Robin K S Phillips
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Phil J Tozer
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| | - Elaine Holmes
- Computational Systems Division, Imperial College London, South Kensington Campus, London, UK
| | - Ailsa L Hart
- Robin Phillips Fistula Research Unit, St Mark's Hospital and Academic Institute, Harrow, Middlesex
- Department of Surgery and Cancer
| |
Collapse
|
11
|
Treatments for the amelioration of persistent factors in complex anal fistula. Biotechnol Lett 2021; 44:23-31. [PMID: 34799826 DOI: 10.1007/s10529-021-03207-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 11/12/2021] [Indexed: 10/19/2022]
Abstract
Anal fistulae are abnormal hollow connections between the wall of the anal canal and the perianal skin around the anus that have remained a burden on the medical sector for centuries. The complexity of this disease is attributed to a number of factors such as the degree of associated sphincter muscle, concomitant illnesses, existence of multiple fistulous tracts and the number of previous interventions. Persistence of a complex anal fistula can cause a decline in patient's physical quality of life as well as impact on the psychological status of patients who often suffer from anxiety and depression. Surgical intervention remains the gold standard for treatment, however; the risk of incontinence and high recurrence potential has led to interest into developing alternative treatment approaches such as the use of biologics, bioactives and biomaterials. One potential reason for these varied outcomes could be the multifactorial interplay between genetic, immune-related, environmental, and microbial persistence factors on tissue regeneration. Recent observations have proposed that adverse inflammatory mediators may contribute more than microbial factors. The moderate to high success rates of biotechnological advances (mesenchymal stem cells and biomaterial scaffolds) show promise as therapies for the amelioration of adverse persistent factors while facilitating a means to closing the fistula tract. The purpose of this review is to outline recent advances in biologics and combination therapies to treat persistent factors associated with complex anal fistula.
Collapse
|
12
|
Jaiswal P, Sharma S, Pratap A, Ansari M, Shukla VK, Basu S, Banerjee T. Significant presence of biofilm-producing gut-derived bacteria in anal fistula of chronic duration. Int Wound J 2021; 18:519-524. [PMID: 33544431 PMCID: PMC8273591 DOI: 10.1111/iwj.13551] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/11/2021] [Indexed: 12/19/2022] Open
Abstract
Fistula-in-ano though not a life-threatening condition, yet its symptoms often significantly impact patients' social, intimate, and work lives. There is an established role of bacterial microflora in acute infections. However, we proposed that biofilm-forming organisms might be present in the microflora of anal fistula of prolonged duration. This aspect has rarely been studied earlier. Therefore, the study describes the microbiology of anal fistula and the biofilm-forming capacity of the isolated organisms. A total of 30 patients were included in the study as per the criteria. Anal fistula tissue sample, tissue fluid, and blood samples were collected from each individual. The collected specimens were detected for the presence of aerobic and anaerobic microflora through standard microbiological method and polymerase chain reaction. Furthermore, the role of biofilm formation by microtitre plate assay and serum matrix metalloproteinases-9 was also studied. The result showed significant predominance of gut-derived microflora with high-to-moderate biofilm-producing ability in anal fistulas of prolonged duration. The study emphasises the presence of biofilm-forming bacteria in chronic, non-healing fistula.
Collapse
Affiliation(s)
- Prakhar Jaiswal
- Department of General Surgery, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| | - Swati Sharma
- Department of Microbiology, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| | - Arvind Pratap
- Department of General Surgery, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| | - Mumtaz Ansari
- Department of General Surgery, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| | - Vijay K Shukla
- Department of General Surgery, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| | - Somprakas Basu
- Department of General SurgeryAll India Institute of Medical SciencesRishikeshUttarakhandIndia
| | - Tuhina Banerjee
- Department of Microbiology, Institute of Medical SciencesBanaras Hindu UniversityVaranasiUttar PradeshIndia
| |
Collapse
|
13
|
Włodarczyk M, Włodarczyk J, Sobolewska-Włodarczyk A, Trzciński R, Dziki Ł, Fichna J. Current concepts in the pathogenesis of cryptoglandular perianal fistula. J Int Med Res 2021; 49:300060520986669. [PMID: 33595349 PMCID: PMC7894698 DOI: 10.1177/0300060520986669] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cryptoglandular perianal fistula is a common benign anorectal disorder that is managed mainly with surgery. A fistula is typically defined as a pathological communication between two epithelialized surfaces. More specifically, perianal fistula manifests as an abnormal tract between the anorectal canal and the perianal skin. Perianal fistulas are often characterized by significantly decreased patient quality of life. The cryptoglandular theory of perianal fistulas suggests their development from the proctodeal glands, which originate from the intersphincteric plane and perforate the internal sphincter with their ducts. Involvement of proctodeal glands in the inflammatory process could play a primary role in the formation of cryptoglandular perianal fistula. The objective of this narrative review was to investigate the current knowledge of the pathogenesis of cryptoglandular perianal fistula with the specific aims of characterizing the potential role of proinflammatory factors responsible for the development of chronic inflammation. Further studies are crucial to improve the therapeutic management of cryptoglandular perianal fistulas.
Collapse
Affiliation(s)
- Marcin Włodarczyk
- Department of General and Colorectal Surgery, Medical University of Lodz, Lodz, Poland.,Department of Biochemistry, Medical University of Lodz, Lodz, Poland
| | - Jakub Włodarczyk
- Department of General and Colorectal Surgery, Medical University of Lodz, Lodz, Poland.,Department of Biochemistry, Medical University of Lodz, Lodz, Poland
| | - Aleksandra Sobolewska-Włodarczyk
- Department of Biochemistry, Medical University of Lodz, Lodz, Poland.,Department of Gastroenterology, Medical University of Lodz, Lodz, Poland
| | - Radzisław Trzciński
- Department of General and Colorectal Surgery, Medical University of Lodz, Lodz, Poland
| | - Łukasz Dziki
- Department of General and Colorectal Surgery, Medical University of Lodz, Lodz, Poland
| | - Jakub Fichna
- Department of Biochemistry, Medical University of Lodz, Lodz, Poland
| |
Collapse
|
14
|
Brar MS, Remzi F, Warusavitarne J, Datta I. Does antibiotic therapy prevent fistula in-ano after incision and drainage of simple perianal abscess? Can J Surg 2020; 63:E362-E364. [PMID: 32813483 DOI: 10.1503/cjs.017119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Mantaj S Brar
- From the Department of Surgery, St. Paul's Hospital, Vancouver, BC (Raval, Morris); and the Department of Surgery, University of Rochester Medical Center, Rochester, New York (Temple)
| | - Feza Remzi
- From the Department of Surgery, St. Paul's Hospital, Vancouver, BC (Raval, Morris); and the Department of Surgery, University of Rochester Medical Center, Rochester, New York (Temple)
| | - Janindra Warusavitarne
- From the Department of Surgery, St. Paul's Hospital, Vancouver, BC (Raval, Morris); and the Department of Surgery, University of Rochester Medical Center, Rochester, New York (Temple)
| | - Indraneel Datta
- From the Department of Surgery, St. Paul's Hospital, Vancouver, BC (Raval, Morris); and the Department of Surgery, University of Rochester Medical Center, Rochester, New York (Temple)
| | | |
Collapse
|
15
|
Cui C, Lu Y, Yue Y, Wu S, Wang S, Yu M, Sun Z. Camel milk regulates T‐cell proliferation to alleviate dextran sodium sulphate‐induced colitis in mice. Int J Food Sci Technol 2020. [DOI: 10.1111/ijfs.14434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Changwan Cui
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Yiping Lu
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Yuanyi Yue
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Si Wu
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Shuang Wang
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Miao Yu
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| | - Zhengrong Sun
- Department of BioBank Sheng Jing Hospital of China Medical University No. 36 Sanhao Street Shenyang 110001 China
| |
Collapse
|
16
|
Jørgensen AHR, Thomsen SF, Karmisholt KE, Ring HC. Clinical, microbiological, immunological and imaging characteristics of tunnels and fistulas in hidradenitis suppurativa and Crohn's disease. Exp Dermatol 2019; 29:118-123. [PMID: 31519056 DOI: 10.1111/exd.14036] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/19/2019] [Accepted: 09/09/2019] [Indexed: 12/20/2022]
Abstract
Hidradenitis suppurativa (HS) tunnels and Crohn's disease (CD) fistulas are a challenge to treat. Although pathogenic similarities have been described between HS and CD, recent studies indicate that clinical, microbiological, immunological and imaging characteristics differ between these diseases. This review highlights the differences between HS tunnels and CD fistulas. Next-generation sequencing studies demonstrate a microbiome in HS tunnels dominated by Porphyromonas spp., Prevotella spp. whereas no specific bacteria have been associated with cutaneous CD. Immunologically, TNF has been found upregulated in HS tunnels along with various interleukins (IL-8, IL-16, IL-1α and IL-1β). In CD fistulas, Th1, Th17, IL-17, IFN-ɤ, TNF and IL-23 are increased. US imaging is an important tool in HS. US of HS tunnels depict hypoechoic band-like structure across skin layers in the dermis and/or hypodermis connected to the base of a widened hair follicle. In CD, MR imaging of simple perianal fistulas illustrates a linear, non-branching inflammatory tract relating to an internal opening in the anus or low rectum and an external opening to the skin surface. An increased awareness of the immediate potential differences between HS tunnels and CD fistulas may optimize treatment regimens of these intractable skin manifestations.
Collapse
Affiliation(s)
| | - Simon Francis Thomsen
- Department of Dermato-Venereology & Wound Healing Centre, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Hans Christian Ring
- Department of Dermato-Venereology & Wound Healing Centre, Bispebjerg Hospital, Copenhagen, Denmark
| |
Collapse
|
17
|
Bislenghi G, Wolthuis A, Van Assche G, Vermeire S, Ferrante M, D'Hoore A. Cx601 (darvadstrocel) for the treatment of perianal fistulizing Crohn's disease. Expert Opin Biol Ther 2019; 19:607-616. [PMID: 31121104 DOI: 10.1080/14712598.2019.1623876] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Introduction: Given the well-documented difficulty to treat perianal fistulizing Crohn's disease (pCD), with 40% of patients experiencing recurrence even after reiterative surgery and advanced medical therapy, research in this field has focused on the role of mesenchymal stem cells (MSC). Areas covered: The aim of this article is to furnish an overview of the pathogenetic mechanisms, clinical applications and evidences for the use of MSC for pCD with particular focus on adipose-derived allogenic MSC including darvadstrocel. Expert Opinion: The effect of MSC on fistula healing is probably mediated by their anti-inflammatory properties more than by their ability to engraft and trans-differentiate in the healthy tissue. A holistic treatment of pCD, addressing different pathophysiological factors, may represent the key for an improvement in the healing rate. In this setting, MSC might play a role as 'augmentation' therapy in combination with more conventional treatments. Whether MSC have benefit in non-complex fistula in biological naïve patients, in complex fistula with many tracts and/or in rectovaginal fistulas, are unexplored fields that need further investigation. A central registry of pCD patients undergoing treatment with MSC should be created in order to elucidate the efficacy, safety and costs of stem cells treatment on long term follow up.
Collapse
Affiliation(s)
- G Bislenghi
- a Department of Abdominal Surgery , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| | - A Wolthuis
- a Department of Abdominal Surgery , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| | - G Van Assche
- b Department of Gastroenterology and Hepatology , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| | - S Vermeire
- b Department of Gastroenterology and Hepatology , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| | - M Ferrante
- b Department of Gastroenterology and Hepatology , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| | - A D'Hoore
- a Department of Abdominal Surgery , University Hospitals Leuven, KU Leuven , Leuven , Belgium
| |
Collapse
|
18
|
Haac BE, Palmateer NC, Seaton ME, VanYPeren R, Fraser CM, Bafford AC. A Distinct Gut Microbiota Exists Within Crohn's Disease-Related Perianal Fistulae. J Surg Res 2019; 242:118-128. [PMID: 31075656 DOI: 10.1016/j.jss.2019.04.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/27/2019] [Accepted: 04/09/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND Gut bacteria are strongly suspected to play a key role in the pathogenesis of Crohn's disease (CD). Studies have demonstrated alterations in the gut microbiota in this patient population. The purpose of this study was to characterize the gut microbiota of fistulizing perianal CD. MATERIALS AND METHODS Stool and fistula samples were obtained from patients undergoing surgery for CD-related anorectal fistulae. Microbial compositions of matched stool and fistula samples were characterized using 16S rRNA gene profiling. The effect of sample type, patient gender, disease classification (Montreal A/B), disease activity (Harvey Bradshaw Index), antibiotic use, and presence of active proctitis on microbial composition was assessed. RESULTS Samples were obtained from 18 patients. Bacteroides was the most abundant genera across all samples collected, followed by Streptococcus and Bifidobacterium. Bifidobacterium was present at significantly higher levels in fecal samples than fistula samples, whereas Achromobacter and Corynebacterium were present at significantly higher levels in fistula samples. Antibiotic, but not thiopurine or antitumor necrosis factor medication, exposure affected the gut microbial composition. Patient gender, disease classification, disease activity, and presence of active proctitis did not alter stool or fistula microbiota. CONCLUSIONS Our data show that the gut microbiota within CD-related anorectal fistulae is distinct from that in stool samples obtained from the same patients. We also observe a dysbiosis in patients treated with antibiotics compared with those not treated with antibiotics.
Collapse
Affiliation(s)
- Bryce E Haac
- Department of Surgery, University of Maryland, Baltimore, Maryland
| | | | - Max E Seaton
- Department of Surgery, University of Maryland, Baltimore, Maryland
| | - Ryan VanYPeren
- Institute for Genome Sciences, University of Maryland, Baltimore, Maryland
| | - Claire M Fraser
- Institute for Genome Sciences, University of Maryland, Baltimore, Maryland
| | - Andrea C Bafford
- Department of Surgery, University of Maryland, Baltimore, Maryland.
| |
Collapse
|
19
|
Ring HC, Sigsgaard V, Thorsen J, Fuursted K, Fabricius S, Saunte DM, Jemec GB. The microbiome of tunnels in hidradenitis suppurativa patients. J Eur Acad Dermatol Venereol 2019; 33:1775-1780. [PMID: 30908704 DOI: 10.1111/jdv.15597] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/06/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease defined by recurrent nodules, tunnels and scarring involving the intertriginous regions. Recent next-generation sequencing (NGS) studies suggest genera such as Prevotella spp., Peptoniphilus spp. and Porphyromonas spp. are associated with chronic and early HS lesions. However, a systematic investigation of the bacterial microbiome in HS tunnels remains unexplored using NGS. OBJECTIVE We aimed to investigate the bacterial composition of the luminal white gelatinous material found in HS tunnels using NGS. METHODS An exploratory study of patients with diagnosis of HS (n = 32) with tunnels. The tunnels were present either in the groin (n = 17) or in the axilla (n = 15). During deroofing of the tunnels, a sterile E-swab was taken of the luminal gelatinous material. The samples were investigated using NGS targeting 16S ribosomal RNA. RESULTS The skin microbiome was characterized in 32 HS patients. Overall, five microbiome types were identified: Porphyromonas spp. (type I), Corynebacterium spp., (type II), Staphylococcus spp. (type III), Prevotella spp. (type IV) and Acinetobacter spp (type V). Porphyromonas spp. (type I) and Prevotella spp. (IV) were the most frequent genera found the tunnels. CONCLUSION This study points to a potential association between the presence of certain anaerobic bacteria (Porphyromonas spp., Prevotella spp.) and HS tunnels. It may be speculated that these two genera are associated with the pathogenesis in HS either as drivers or as biomarkers.
Collapse
Affiliation(s)
- H C Ring
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark.,Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark
| | - V Sigsgaard
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark.,Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark
| | - J Thorsen
- COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - K Fuursted
- Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | - S Fabricius
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark.,Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark
| | - D M Saunte
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark.,Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark
| | - G B Jemec
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark.,Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
20
|
Affiliation(s)
- Martijn Pieter Gosselink
- Department of Colorectal Surgery, Westmead Hospital, The University of Sydney Westmead Clinical School, Sydney, NSW, Australia.,Centre for Virus Research, Westmead Institute for Medical Research, Westmead, NSW, Australia.,University of Sydney, Sydney, NSW, Australia
| | - Andrew N Harman
- Centre for Virus Research, Westmead Institute for Medical Research, Westmead, NSW, Australia.,University of Sydney, Sydney, NSW, Australia.,The School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Grahame Ctercteko
- Department of Colorectal Surgery, Westmead Hospital, The University of Sydney Westmead Clinical School, Sydney, NSW, Australia
| |
Collapse
|
21
|
|
22
|
Efficacy of Medical Therapies for Fistulizing Crohn's Disease: Systematic Review and Meta-analysis. Clin Gastroenterol Hepatol 2018; 16:1879-1892. [PMID: 29374617 DOI: 10.1016/j.cgh.2018.01.030] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/24/2017] [Accepted: 01/05/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Fistulas are debilitating complications of Crohn's disease (CD) that affect up to 50% of patients. We conducted a systematic review and meta-analysis of randomized controlled trials to assess the efficacy of treatments for fistulizing CD. METHODS We searched publication databases from inception through December 13, 2016 for trials comparing the efficacy of a therapeutic agent (single or combination) with placebo or another active therapy in adult patients with any form of fistulizing CD. The Cochrane risk of bias tool was used to assess the methodological quality of trials; the overall quality of evidence was evaluated using GRADE. Primary outcomes included induction and maintenance of fistula response and remission. Pooled risk ratios (RRs) and 95% CIs were calculated for each outcome. RESULTS We analyzed data from 27 trials; most studies (21/27) focused on patients with perianal fistulizing CD. We found moderate-quality evidence to support the efficacy of tumor necrosis factor (TNF) antagonists (RR, 2.01; 95% CI, 1.36-2.97), particularly infliximab, ustekinumab (RR, 1.77; 95% CI, 0.93-3.37), and mesenchymal stem cell therapy (RR, 1.31; 95% CI, 0.98-1.73) for induction of fistula remission. We found low-quality evidence for the efficacy of vedolizumab and immunosuppressives. There was also low-quality evidence to support the efficacy of combination therapy with TNF antagonists and antibiotics vs a TNF antagonist alone. CONCLUSION In a systematic review and meta-analysis of 27 controlled trials, we found TNF antagonists to be effective for induction and maintenance of perianal fistula response and remission. There are few data on the effects on internal fistulae. Further studies are needed, particularly for ustekinumab, vedolizumab, and stem cell therapies, in patients with fistulizing CD.
Collapse
|
23
|
Tozer PJ, Lung P, Lobo AJ, Sebastian S, Brown SR, Hart AL, Fearnhead N. Review article: pathogenesis of Crohn's perianal fistula-understanding factors impacting on success and failure of treatment strategies. Aliment Pharmacol Ther 2018; 48:260-269. [PMID: 29920706 DOI: 10.1111/apt.14814] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 01/22/2018] [Accepted: 04/30/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND Evidence from groups who have studied fistula aetiology and extrapolation from interventional studies supports a multifactorial hypothesis of Crohn's perianal fistula, with several pathophysiological elements that may contribute to fistula formation, persistence and resistance to treatment. AIM An evidence synthesis of current understanding of pathophysiological factors underlying Crohn's perianal fistula is presented, exploring the fundamental reasons why some treatments succeed and others fail, as a means of focussing clinical knowledge on improving treatment of Crohn's perianal fistula. METHODS Evidence to support this review was gathered via the Pubmed database. Studies discussing pathophysiological factors underpinning perianal fistula, particularly in Crohn's disease, were reviewed and cross-referenced for additional reports. RESULTS Pathophysiological factors that impact on success or failure of interventions for Crohn's perianal fistulae include the high-pressure zone, obliterating the dead space, disconnecting the track from the anus, removing epithelialisation, eradicating sepsis and by-products of bacterial colonisation, correcting abnormalities in wound repair and removing the pro-inflammatory environment which allows fistula persistence. Most current interventions for Crohn's perianal fistulae tend to focus on a single, or at best two, aspects of the pathophysiology of Crohn's anal fistulae; as a result, failure to heal fully is common. CONCLUSIONS For an intervention or combination of interventions to succeed, multiple factors must be addressed. We hypothesise that correct, timely and complete attention to all of these factors in a multimodal approach represents a new direction that may enable the creation of an effective treatment algorithm for Crohn's anal fistula.
Collapse
Affiliation(s)
- P J Tozer
- St Mark's Hospital and Imperial College London, London, UK
| | - P Lung
- St Mark's Hospital and Imperial College London, London, UK
| | - A J Lobo
- Academic Unit of Gastroenterology, University of Sheffield, Sheffield, UK
| | - S Sebastian
- IBD Unit, Hull and East Yorkshire Hospitals NHS Trust, Hull, UK
| | - S R Brown
- Sheffield Teaching Hospitals, Sheffield, UK
| | - A L Hart
- St Mark's Hospital and Imperial College London, London, UK
| | - N Fearnhead
- Addenbrookes Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
24
|
Williams G, Williams A, Tozer P, Phillips R, Ahmad A, Jayne D, Maxwell-Armstrong C. The treatment of anal fistula: second ACPGBI Position Statement - 2018. Colorectal Dis 2018; 20 Suppl 3:5-31. [PMID: 30178915 DOI: 10.1111/codi.14054] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 02/16/2018] [Indexed: 02/08/2023]
Abstract
It is over 10 years since the first ACPGBI Position Statement on the management of anal fistula was published in 2007. This second edition is the result of scrutiny of the literature published during this time; it updates the original Position Statement and reviews the published evidence surrounding treatments for anal fistula that have been developed since the original publication.
Collapse
Affiliation(s)
- G Williams
- Royal Wolverhampton NHS Trust, Wolverhampton, UK
| | - A Williams
- Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - P Tozer
- St Mark's Hospital, Harrow, London, UK
| | | | - A Ahmad
- Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - D Jayne
- University of Leeds, Leeds, UK
| | - C Maxwell-Armstrong
- National Institute for Health Research Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| |
Collapse
|
25
|
Sugrue J, Nordenstam J, Abcarian H, Bartholomew A, Schwartz JL, Mellgren A, Tozer PJ. Pathogenesis and persistence of cryptoglandular anal fistula: a systematic review. Tech Coloproctol 2017. [PMID: 28620877 DOI: 10.1007/s10151-017-1645-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Anal fistulas continue to be a problem for patients and surgeons alike despite scientific advances. While patient and anatomical characteristics are important to surgeons who are evaluating patients with anal fistulas, their development and persistence likely involves a multifaceted interaction of histological, microbiological, and molecular factors. Histological studies have shown that anal fistulas are variably epithelialized and are surrounded by dense collagen tissue with pockets of inflammatory cells. Yet, it remains unknown if or how histological differences impact fistula healing. The presence of a perianal abscess that contains gut flora commonly leads to the development of anal fistula. This implies a microbiological component, but bacteria are infrequently found in chronic fistulas. Recent work has shown an increased expression of proinflammatory cytokines and epithelial to mesenchymal cell transition in both cryptoglandular and Crohn's perianal fistulas. This suggests that molecular mechanisms may also play a role in both fistula development and persistence. The aim of this study was to examine the histological, microbiological, molecular, and host factors that contribute to the development and persistence of anal fistulas.
Collapse
Affiliation(s)
- Jeremy Sugrue
- Division of Colon and Rectal Surgery, University of Illinois at Chicago, 840 S Wood St, Suite 376-CSN, Chicago, IL, 60612, USA.
| | - Johan Nordenstam
- Division of Colon and Rectal Surgery, University of Illinois at Chicago, 840 S Wood St, Suite 376-CSN, Chicago, IL, 60612, USA
| | - Herand Abcarian
- Division of Colon and Rectal Surgery, University of Illinois at Chicago, 840 S Wood St, Suite 376-CSN, Chicago, IL, 60612, USA
| | - Amelia Bartholomew
- Department of Surgery, University of Illinois at Chicago, Chicago, IL, USA
| | - Joel L Schwartz
- Department of Oral Medicine and Diagnostic Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Anders Mellgren
- Division of Colon and Rectal Surgery, University of Illinois at Chicago, 840 S Wood St, Suite 376-CSN, Chicago, IL, 60612, USA
| | - Philip J Tozer
- St. Mark's Hospital, London, UK.,Imperial College London, London, UK
| |
Collapse
|
26
|
Ommer A, Herold A, Berg E, Farke S, Fürst A, Hetzer F, Köhler A, Post S, Ruppert R, Sailer M, Schiedeck T, Schwandner O, Strittmatter B, Lenhard BH, Bader W, Krege S, Krammer H, Stange E. S3-Leitlinie: Kryptoglanduläre Analfisteln. COLOPROCTOLOGY 2016. [DOI: 10.1007/s00053-016-0110-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
27
|
Ratto C, Litta F, Lucchetti D, Parello A, Boninsegna A, Arena V, Donisi L, Calapà F, Sgambato A. Immunopathological characterization of cryptoglandular anal fistula: a pilot study investigating its pathogenesis. Colorectal Dis 2016; 18:O436-O444. [PMID: 27649390 DOI: 10.1111/codi.13527] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 09/05/2016] [Indexed: 12/19/2022]
Abstract
AIM The pathogenesis of cryptoglandular anal fistula (AF) is still under debate. Tissue inflammation could play a primary role. The pathological process of epithelial mesenchymal transition (EMT) might be involved but has never been investigated. METHOD In a prospective pilot study, 12 patients with an AF had a fistulectomy. The excised track was divided into proximal (intrasphincteric) and distal (extrasphincteric) parts which were subjected to standard histopathological examination. The cytokines IL-8 and IL-1beta were analysed as markers of inflammation, while EMT was evaluated by expression of TGF-beta, Vimentin, Zeb-1, Snail and E-cadherin. The mRNA and protein expression of these molecules was investigated by real-time PCR (RT-PCR), Western blot analysis and immunohistochemistry and was compared with that of the normal adjacent tissue. RESULTS Chronic inflammation and granulation tissue and a stratified epithelium were evident on standard histopathological examination. The cytokine IL-8 was more expressed in the proximal than the distal part of the track (fold increase 4.34 vs 3.60), while the reverse was found for IL-1beta (fold increase 1.33 vs 2.01); both were more intensely expressed compared with the normal anal mucosa. EMT was demonstrated, in both proximal and distal parts of the track, with an increase of TGF-beta, Vimentin, Zeb-1 and Snail and a mean decrease of E-cadherin. Western blot analysis and immunohistochemistry confirmed the protein expression. CONCLUSION The study suggests that chronic inflammation is present in cryptoglandular fistulas. The inflammatory pattern might be different in the proximal than in the distal part of the fistula track. The cytokines IL-1beta and IL-8 could play a possible role in fistula formation. The study demonstrates for the first time the potential importance of EMT in the pathogenesis of cryptoglandular AF.
Collapse
Affiliation(s)
- C Ratto
- Proctology Unit, Department of Surgical Sciences, Catholic University of Rome, Rome, Italy
| | - F Litta
- Proctology Unit, Department of Surgical Sciences, Catholic University of Rome, Rome, Italy
| | - D Lucchetti
- Institute of General Pathology, Catholic University of Rome, Rome, Italy
| | - A Parello
- Proctology Unit, Department of Surgical Sciences, Catholic University of Rome, Rome, Italy
| | - A Boninsegna
- Institute of General Pathology, Catholic University of Rome, Rome, Italy
| | - V Arena
- Department of Pathology, Catholic University of Rome, Rome, Italy
| | - L Donisi
- Proctology Unit, Department of Surgical Sciences, Catholic University of Rome, Rome, Italy
| | - F Calapà
- Institute of General Pathology, Catholic University of Rome, Rome, Italy
| | - A Sgambato
- Institute of General Pathology, Catholic University of Rome, Rome, Italy
| |
Collapse
|
28
|
|
29
|
van Onkelen RS, Gosselink MP, van Meurs M, Melief MJ, Schouten WR, Laman JD. Pro-inflammatory cytokines in cryptoglandular anal fistulas. Tech Coloproctol 2016; 20:619-25. [PMID: 27402195 PMCID: PMC5003909 DOI: 10.1007/s10151-016-1494-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/26/2016] [Indexed: 11/30/2022]
Abstract
Background Sphincter-preserving procedures for the treatment of transsphincteric fistulas fail in at least one out of every three patients. It has been suggested that failure is due to ongoing disease in the remaining fistula tract. Cytokines play an important role in inflammation. At present, biologicals targeting cytokines are available. Therefore, detection and identification of cytokines in anal fistulas might have implications for future treatment modalities. The objective of the present study was to assess local production of a selected panel of cytokines in anal fistulas, including pro-inflammatory interleukin (IL)-1β and tumor necrosis factor α (TNF-α). Methods Fistula tract tissue was obtained from 27 patients with a transsphincteric fistula of cryptoglandular origin who underwent flap repair, ligation of the intersphincteric fistula tract or a combination of both procedures. Patients with a rectovaginal fistula or a fistula due to Crohn’s disease were excluded. Frozen tissue samples were sectioned and stained using advanced immuno-enzyme staining methods for detection of selected cytokines, IL-1β, IL-8, IL-10, IL-12p40, IL-17A, IL-18, IL-36 and TNF-α. The presence and frequencies of cytokine-producing cells in samples were quantitated. Results The key finding was abundant expression of IL-1β in 93 % of the anal fistulas. Frequencies of IL-1β-producing cells were highest (>50 positive stained cells) in 7 % of the anal fistulas. Also, cytokines IL-8, IL-12p40 and TNF-α were present in respectively 70, 33 and 30 % of the anal fistulas. Conclusions IL-1β is expressed in the large majority of cryptoglandular anal fistulas, as well as several other pro-inflammatory cytokines.
Collapse
Affiliation(s)
- R S van Onkelen
- Department of Surgery, Erasmus Medical Center Rotterdam, University Medical Center, Room H 181's Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands. .,Department of Immunology, Erasmus MC, University Medical Center, MS Center ErasMS, Rotterdam, The Netherlands.
| | - M P Gosselink
- Department of Surgery, Maasstad Hospital, Rotterdam, The Netherlands
| | - M van Meurs
- Department of Immunology, Erasmus MC, University Medical Center, MS Center ErasMS, Rotterdam, The Netherlands
| | - M J Melief
- Department of Immunology, Erasmus MC, University Medical Center, MS Center ErasMS, Rotterdam, The Netherlands
| | - W R Schouten
- Department of Surgery, Erasmus Medical Center Rotterdam, University Medical Center, Room H 181's Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands
| | - J D Laman
- Department of Immunology, Erasmus MC, University Medical Center, MS Center ErasMS, Rotterdam, The Netherlands.,Department of Neuroscience, University Medical Center, University of Groningen, Groningen, The Netherlands
| |
Collapse
|
30
|
Hoffman AM, Dow SW. Concise Review: Stem Cell Trials Using Companion Animal Disease Models. Stem Cells 2016; 34:1709-29. [PMID: 27066769 DOI: 10.1002/stem.2377] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 03/26/2016] [Indexed: 12/13/2022]
Abstract
Studies to evaluate the therapeutic potential of stem cells in humans would benefit from more realistic animal models. In veterinary medicine, companion animals naturally develop many diseases that resemble human conditions, therefore, representing a novel source of preclinical models. To understand how companion animal disease models are being studied for this purpose, we reviewed the literature between 2008 and 2015 for reports on stem cell therapies in dogs and cats, excluding laboratory animals, induced disease models, cancer, and case reports. Disease models included osteoarthritis, intervertebral disc degeneration, dilated cardiomyopathy, inflammatory bowel diseases, Crohn's fistulas, meningoencephalomyelitis (multiple sclerosis-like), keratoconjunctivitis sicca (Sjogren's syndrome-like), atopic dermatitis, and chronic (end-stage) kidney disease. Stem cells evaluated in these studies included mesenchymal stem-stromal cells (MSC, 17/19 trials), olfactory ensheathing cells (OEC, 1 trial), or neural lineage cells derived from bone marrow MSC (1 trial), and 16/19 studies were performed in dogs. The MSC studies (13/17) used adipose tissue-derived MSC from either allogeneic (8/13) or autologous (5/13) sources. The majority of studies were open label, uncontrolled studies. Endpoints and protocols were feasible, and the stem cell therapies were reportedly safe and elicited beneficial patient responses in all but two of the trials. In conclusion, companion animals with naturally occurring diseases analogous to human conditions can be recruited into clinical trials and provide realistic insight into feasibility, safety, and biologic activity of novel stem cell therapies. However, improvements in the rigor of manufacturing, study design, and regulatory compliance will be needed to better utilize these models. Stem Cells 2016;34:1709-1729.
Collapse
Affiliation(s)
- Andrew M Hoffman
- Regenerative Medicine Laboratory, Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, Grafton, Massachusetts, USA
| | - Steven W Dow
- Center for Immune and Regenerative Medicine, Department of Clinical Sciences, Colorado State University, Fort Collins, Colorado, USA
| |
Collapse
|
31
|
Affiliation(s)
- Martijn Pieter Gosselink
- Department of Colorectal Surgery, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
| | | | - W R Schouten
- Department of Colorectal Surgery, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| |
Collapse
|
32
|
Tozer P, Borowski DW, Gupta A, Yassin N, Phillips R, Hart A. Managing perianal Crohn's fistula in the anti-TNFα era. Tech Coloproctol 2015; 19:673-8. [PMID: 26264168 DOI: 10.1007/s10151-015-1332-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 06/22/2015] [Indexed: 12/18/2022]
Abstract
Perianal fistulas in Crohn's disease are common and difficult to treat. Their aetiology is poorly understood. Assessment is clinical, endoscopic and radiological, and management is undertaken by a multidisciplinary team of gastroenterologists, surgeons and radiologists. Surgical drainage of the fistula tract system with the placement of loose setons precedes combined therapy with immunosuppressant and anti-TNFα agents in most patients. Proctitis should be rigorously eliminated where possible. Definitive surgical repair is sometimes possible and diversion or proctectomy are occasionally required. Combined medical and surgical management represents a promising avenue for the future.
Collapse
Affiliation(s)
- P Tozer
- Fistula Research Unit, St Mark's Hospital, Imperial College London, London, UK.
| | - D W Borowski
- University Hospital North Tees, Stockton on Tees, Cleveland, UK
| | - A Gupta
- Fistula Research Unit, St Mark's Hospital, Imperial College London, London, UK
| | - N Yassin
- Fistula Research Unit, St Mark's Hospital, Imperial College London, London, UK
| | - R Phillips
- Fistula Research Unit, St Mark's Hospital, Imperial College London, London, UK
| | - A Hart
- Fistula Research Unit, St Mark's Hospital, Imperial College London, London, UK
| |
Collapse
|
33
|
van Onkelen RS, Gosselink MP, Laman JD, Schouten WR. Inflammation in anal fistula. Colorectal Dis 2015; 17:643-4. [PMID: 25951235 DOI: 10.1111/codi.12991] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 04/22/2015] [Indexed: 02/08/2023]
Affiliation(s)
- R S van Onkelen
- Department of Surgery, Erasmus MC, University Medical Center, Rotterdam, The Netherlands. .,Department of Immunology, Erasmus MC, University Medical Center and MS Center ErasMS, Rotterdam, The Netherlands.
| | - M P Gosselink
- Department of Surgery, Maasstad Hospital, Rotterdam, The Netherlands
| | - J D Laman
- Department of Immunology, Erasmus MC, University Medical Center and MS Center ErasMS, Rotterdam, The Netherlands.,Department of Neuroscience and Medical Physiology, University of Groningen, University Medical Center, Groningen, The Netherlands
| | - W R Schouten
- Department of Surgery, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| |
Collapse
|