Suspected coexistence of perianal necrotizing sweet syndrome in chronic myelomonocytic leukemia:A case report

BACKGROUND Chronic myelomonocytic leukemia(CMML)complicated with Sweet syndrome(SS)is a rare hematological neoplasm.However,cases of concomitant development of perianal necrotizing SS(NSS)have not been reported.CASE SUMMARY We report a case of a 49-year-old male patient who underwent sequential procedures for hemorrhoids and perianal abscess.He developed postoperative incision infection and was referred to the department where the authors work.Initially,perianal necrotizing fasciitis secondary to incision infection after perianal abscess surgery was suspected.Despite receiving antibiotic therapy and undergoing surgical debridement,deeper necrotic areas formed in the patient’s perianal wounds,accompanied by persistent high fever.Blood and fungal cultures yielded negative results.The final diagnosis was corrected to be CMML with suspected concomitant perianal NSS.CONCLUSION CMML with perianal NSS is a rare condition,often misdiagnosed as perianal abscess or perianal necrotizing fasciitis.Conventional antibiotic therapy and surgical debridement are ineffective in managing this condition.

A case study illustrating the use of an integrated approach to treat secondary Anal Fistula Post I&D of Perianal Abscess

Background:Anal fistula is a long-term disease characterized by a tubular structure with one end opening in the anorectal canal and the other end opening on the surface of the perineum or perianal skin with chronic pus drainage.It is linked to Bhagandar in Ayurveda,and in Sushruta Samhita,Acharya has mentioned 5 forms of Bhagandar.The boil in the present case was Shukla,sthira i.e.hard and firm,with Picchila strava and Kandu resembling the features of Parisraavi bhagandar.Aim and objective:The current case was diagnosed as Parisravi bhagandar,which resembles trans-sphincteric or intersphincteric fistula in modern ano.In Ayurveda,the management of Parisraavi Bhagandar,Shastra,kshara,and Agnikarma is advised and the use of Ksharasutra,which contributes to complete cutting and healing of the track without reoccurrence,similarly Modern surgeon depends on surgery i.e radical excision of the track,ligation with Seton,and use of chemical irritants like urethane,silver nitrates,etc.A cutting seton(tight)gently slices the confined muscle to close the fistula with the least interruption to continence.This operation is especially advised when a one-stage fistulotomy poses a considerable risk of incontinence.Material and methods:The method performed here was Core Partial Fistulectomy followed by Ksharasutra application till complete healing of the wound.Discussion and conclusion:This case study provides the successful management of Parisraavi Bhagandara(high anal,trans-sphincteric fistula in ano)in 61-year-old male patient with an integrated surgical&Ayurvedic management approach.

Clinical Study on the Effectiveness of Xian Fang Huo Ming Yin for Treating Cutaneous Infections and Promoting Wound Healing in Patients with Perianal Abscess

Objective:To explore the effect of the Xian Fang Huo Ming Yin(XFHM)for treating cutaneous infections and promoting wound healing in patients with perianal abscesses.Methods:Sixty-one patients with perianal abscesses who were admitted to our hospital(Xinghua City People’s Hospital)from May 2022 to May 2023 were selected and randomly divided into two groups,a control group(30 cases)and a study group(31 cases).Both groups received surgical treatment.The control group received conventional treatment and warm water fumigation,sitz bath,and surgical dressing change after surgery,while the research group received XFHM based on the control group.XFHM was taken orally and replaced with warm water for fumigation and sitz bathing.Both groups received treatment for 4 weeks but discontinued sitz bathing after 2 weeks.Various clinical indicators between the two groups were compared.Results:The total clinical effective rate and wound recovery rate of the study group were higher than that of the control group.There were differences in the wound pain scores,surrounding tissue edema,and wound secretions at different time points.Both groups experienced wound pain.The scores of wound pain,surrounding tissue edema,and wound secretions of the study group were lower than those of the control group,7 and 14 days after surgery.The serum interleukin 6(IL-6),tumor necrosis factor-alpha(TNF-α)levels,and pH values of the study group were lower than those of the control group 10 days after surgery(P<0.05).Conclusion:The application of XFHM for treating cutaneous infections and promoting wound healing in patients with perianal abscesses improved the treatment outcome,alleviated clinical symptoms,and promoted healing.

Up-to-date meta-analysis of long-term evaluations of mesenchymal stem cell therapy for complex perianal fistula

BACKGROUND Local mesenchymal stem cell(MSC)therapy for complex perianal fistulas(PFs)has shown considerable promise.But,the long-term safety and efficacy of MSC therapy in complex PFs remain unknown.AIM To explore the long-term effectiveness and safety of local MSC therapy for complex PFs.METHODS Sources included the PubMed,EMBASE,and Cochrane Library databases.A standard meta-analysis was performed using RevMan 5.3.RESULTS After screening,6 studies met the inclusion criteria.MSC therapy was associated with an improved long-term healing rate(HR)compared with the control condition[odds ratio(OR)=2.13;95%confidence interval(95%CI):1.34 to 3.38;P=0.001].Compared with fibrin glue(FG)therapy alone,MSC plus FG therapy was associated with an improved long-term HR(OR=2.30;95%CI:1.21 to 4.36;P=0.01).When magnetic resonance imaging was used to evaluate fistula healing,MSC therapy was found to achieve a higher long-term HR than the control treatment(OR=2.79;95%CI:1.37 to 5.67;P=0.005).There were no significant differences in long-term safety(OR=0.77;95%CI:0.27 to 2.24;P=0.64).CONCLUSION Our study indicated that local MSC therapy promotes long-term and sustained healing of complex PFs and that this method is safe.

Multi-national observational study to assess quality of life and treatment preferences in patients with Crohn’s perianal fistulas

BACKGROUND Patients with Crohn’s disease(CD)are at risk of developing complications such as perianal fistulas.Patients with Crohn’s perianal fistulas(CPF)are affected by fecal incontinence(FI),bleeding,pain,swelling,and purulent perianal discharge,and METHODS This cross-sectional observational study was conducted in patients with CD aged 21-90 years via a web-enabled questionnaire in seven countries(April-August 2021).Patients were recruited into three cohorts:Cohort 1 included patients without perianal fistulas;cohort 2 included patients with perianal fistulas without fistula-related surgery;and cohort 3 included patients with perianal fistulas and fistula-related surgery.Validated patient-reported outcome measures were used to assess quality of life.Drivers of treatment preferences were measured using a discrete choice experiment(DCE).RESULTS In total,929 patients were recruited(cohort 1,n=620;cohort 2,n=174;cohort 3,n=135).Short Inflammatory Bowel Disease Questionnaire scores were worse for patients with CPF(cohorts 2 and 3)than for those with CD without CPF(cohort 1):Mean score 3.8 and 3.7 vs 4.1,respectively,(P<0.001).Similarly,mean Revised FI and FI Quality of Life scores were worse for patients with CPF than for those with CD without CPF.Quality of Life with Anal Fistula scores were similar in patients with CPF with or without CPF-related surgery(cohorts 2 and 3):Mean score 41 and 42,respectively.In the DCE,postoperative discomfort and fistula healing rate were the most important treatment attributes influencing treatment choice:Mean relative importance 35.7 and 24.7,respectively.CONCLUSION The burden of illness in CD is significantly higher for patients with CPF and patients rate lower postoperative discomfort and higher healing rates as the most desirable treatment attributes.

Malignant transformation of perianal tailgut cyst:A case report

BACKGROUND Tailgut cyst is a congenital enterogenous cyst that rarely undergoes malignant transformation.Its clinical manifestations mainly correlate to the mass effect caused by the development of cysts and the infections that originate from these.Furthermore,the complete resection of this cyst is curative.We report our diagnostic and treatment experience with one case of malignant transformation of a perianal tailgut cyst,which was initially misdiagnosed as perianal abscess.CASE SUMMARY A 72-year-old woman visited our institution with complaints of a refractory nonhealing lesion on the right hip,which repeatedly broke and suppurated for more than 70 years,and aggravated in 4 mo.The patient was given a diagnosis of refractory perianal abscess with repeated incision and drainage procedures.Computed tomography of the pelvic cavity revealed a giant perianal cyst.Subsequent biopsy revealed a tumor with moderate-to-severe glandular epithelial dysplasia,and suggested that this was derived from the developmental cysts in the posterior rectal space.After further clarifying the nature and extent of the tumor by magnetic resonance imaging,total cystic resection was performed.Postoperative histopathological examination confirmed the malignancy,dictating the investigators to add postoperative chemotherapy to the treatment regimen.CONCLUSION The malignant transformation of perianal tailgut cysts is very uncommon,and this should be differentiated from perianal abscess.Complete surgical removal is curative,and postoperative pathology may determine the necessity of additional postoperative chemotherapy or radiotherapy,which may be beneficial for preventing local recurrence and metastasis.

Indications and surgical options for small bowel, large bowel and perianal Crohn's disease

Despite advancements in medical therapy of Crohn's disease(CD), majority of patients with CD will eventually require surgical intervention, with at least a third of patients requiring multiple surgeries. It is important to understand the role and timing of surgery, with the goals of therapy to reduce the need for surgery without increasing the odds of emergency surgery and its associated morbidity, as well as to limit surgical recurrence and avoid intestinal failure. The profile of CD patients requiring surgical intervention has changed over the decades with improvements in medical therapy with immunomodulators and biological agents. The most common indication for surgery is obstruction from stricturing disease, followed by abscesses and fistulae. The risk of gastrointestinal bleeding in CD is high but the likelihood of needing surgery for bleeding is low. Most major gastrointestinal bleeding episodes resolve spontaneously, albeit the risk of re-bleeding is high. The risk of colorectal cancer associated with CD is low. While current surgical guidelines recommend a total proctocolectomy for colorectal cancer associated with CD, subtotal colectomy or segmental colectomy with endoscopic surveillance may be a reasonable option. Approximately 20%-40% of CD patients will need perianal surgery during their lifetime. This review assesses the practice parameters and guidelines in the surgical management of CD, with a focus on the indications for surgery in CD(and when not to operate), and a critical evaluation of the timing and surgical options available to improve outcomes and reduce recurrence rates.

Three-dimensional endoanal ultrasound for diagnosis of perianal fistulas: reliable and objective technique

AIM: To evaluate accuracy of three-dimensional endoanal ultrasound(3D-EAUS) as compared to 2D-EAUS and physical examination(PE) in diagnosis of perianal fistulas and correlate with intraoperative findings. METHODS: A prospective observational consecutive study was performed with patients included over a two years period. All patients were studied and operated on by the Colorectal Unit surgeons. The inclusion criteria were patients over 18, diagnosed with a criptoglandular perianal fistula. The PE, 2D-EAUS and 3D-EAUS was performed preoperatively by the same colorectal surgeon at the outpatient clinic prior to surgery and the fistula anatomy was defined and they were classified in intersphincteric, high or low transsphincteric, suprasphincteric and extrasphincteric. Special attention was paid to the presence of a secondary tract, the location of the internal opening(IO) and the site of external opening. The results of these different examinations were compared to the intraoperative findings. Data regarding location of the IO, primary tract, secondary tract, and the presence of abscesses or cavities wasanalysed.RESULTS: Seventy patients with a mean age of 47years(range 21-77), 51 male were included. Low transsphincteric fistulas were the most frequent type found(33, 47.1%) followed by high transsphincteric(24,34.3%) and intersphincteric fistulas(13, 18.6%). There are no significant differences between the number of IO diagnosed by the different techniques employed and surgery(P > 0.05) and, there is a good concordance between intraoperative findings and the 2D-EAUS(k= 0.67) and 3D-EAUS(k = 0.75) for the diagnosis of the primary tract. The ROC curves for the diagnosis of transsphincteric fistulas show that both ultrasound techniques are adequate for the diagnosis of low transsphincteric fistulas, 3D-EAUS is superior for the diagnosis of high transsphincteric fistulas and PE is weak for the diagnosis of both types.CONCLUSION: 3D-EAUS shows a higher accuracy than 2D-EAUS for assessing height of primary tract in transsphincteric fistulas. Both techniques show a good concordance with intraoperative finding for diagnosis of primary tracts.

Management of perianal fistulas in Crohn's disease:An upto-date review

Perianal disease is one of the most disabling manifestations of Crohn's disease.A multidisciplinary approach of gastroenterologist,colorectal surgeon and radiologist is necessary for its management.A correct diagnosis,based on endoscopy,magnetic resonance imaging,endoanal ultrasound and examination under anesthesia,is crucial for perianal fistula treatment.Available medical and surgical therapies are discussedin this review,including new local treatment modalities that are under investigation.

Burden and outcomes for complex perianal fistulas in Crohn's disease:Systematic review

AIM To systematically review the literature on epidemiology,disease burden, and treatment outcomes for Crohn's disease(CD) patients with complex perianal fistulas.METHODS PubMed, Embase, and Cochrane were searched for relevant articles(published 2000-November 2016) and congress abstracts(published 2011-November 2016).RESULTS Of 535 records reviewed, 62 relevant sources were identified(mostly small observational studies). The cumulative incidence of complex perianal fistulas in CD from two referral-centre studies was 12%-14%(follow-up time, 12 years in one study; not reported in the second study). Complex perianal fistulas result in greatly diminished quality of life; up to 59% of patients are at risk of faecal incontinence. Treatments include combinations of medical and surgical interventions and expanded allogeneic adipose-derived stem cells. High proportions of patients experience lack of or inadequate response to treatment(failure and relapse rates,respectively: medical, 12%-73% and 0%-41%; surgical:0%-100% and 11%.20%; combined medical/surgical:0%-80% and 0%-50%; stem cells: 29%-47% and not reported). Few studies(1 of infliximab; 3 of surgical interventions)have been conducted in treatment-refractory patients, a population with high unmet needs. Limited data exist on the clinical value of anti-tumour necrosis factor-α dose escalation in patients with complex perianal fistulas in CD.CONCLUSION Complex perianal fistulas in CD pose substantial clinical and humanistic burden. There is a need for effective treatments, especially for patients refractory to antitumour necrosis factor-α agents, as evidenced by high failure and relapse rates.

Retrospective analysis of perianal Paget's disease with underlying anorectal carcinoma

AIM:To analyze clinical and pathological characteristics of an aggressive subtype of perianal Paget's disease(PPD) and explore its rational treatment modalities.METHODS:PPD patients were retrospectively collected in the institutional colorectal database of the Fudan University Shanghai Cancer Center.Detailed patient histories of past medical condition,diagnosis,treatment,and pathological findings were reviewed.Surgical specimen from diagnosis and surgery were reviewed by two independent pathologists for confirmation of diagnoses.Follow up was accomplished by clinical interview by cellphone.RESULTS:In total,eight cases of PPD were analyzed.All patients had underlying anorectal adenocarcinoma,including seven with synchronous lesions and one with metachronous lesions.Moreover,all anorectal lesions had a mucin-producing component.The median age at diagnosis was 65(range 29-81 years),and the male/female ratio was 7:1.The Median follow-up time of all patients was 61.5 mo(range 10-204 mo).One patient treated with abdominoperineal resection(APR) died from lung metastases 10 mo after the APR operation.The other patients are still free of disease at the time of this analysis.CONCLUSION:PPD is a rare malignancy and is easily misdiagnosed.Underlying anorectal cancer was not unusual and was a significant prognostic factor.Rational treatment of both anorectal cancer and PPD lesion is essential for long-term survival.

Does capsule endoscopy have an added value in patients with perianal disease and a negative work up for Crohn's disease?

AIM:To investigate the role of capsule endoscopy in patients with persistent perianal disease and negative conventional work up for Crohn's disease(CD).METHODS:Patients with perianal disease(abscesses,fistulas,recurrent fissures) were evaluated for underlying CD.Patients who had a negative work up,defined as a negative colonoscopy with a normal ileoscopy or a normal small bowel series or a normal CT/MR enterography,underwent a Pillcam study of the small bowel after signing informed consent.Patients using nonsteroidal anti-inflammatory drugs or who had a history of inflammatory bowel disease or rheumatic disease were excluded.RESULTS:We recruited 26 patients aged 21-61 years(average 35.6 years),17 males and 9 females.One case could not be evaluated since the capsule did not leave the stomach.In 6 of 25(24%) patients with a negative standard work up for Crohn's disease,capsuleendoscopy(CE) findings were consistent with Crohn's disease of the small bowel.Family history of CD,white blood cell,hemoglobin,erythrocyte sedimentation rate or C-reactive protein did not predict a diagnosis of CD.Capsule endoscopy findings led to a change in treatment.CONCLUSION:In patients with perianal disease and a negative conventional work up to exclude CD,CE leads to incremental diagnostic yield of 24%.

Modern surgical strategies for perianal Crohn's disease

One of the most challenging phenotypes of Crohn’s disease is perianal fistulizing disease(PFCD).It occurs in up to 50%of the patients who also have symptoms in other parts of the gastrointestinal tract,and in 5%of the cases it occurs as the first manifestation.It is associated with severe symptoms,such as pain,fecal incontinence,and a significant reduction in quality of life.The presence of perianal disease in conjunction with Crohn’s disease portends a significantly worse disease course.These patients require close monitoring to identify those at risk of worsening disease,suboptimal biological drug levels,and signs of developing neoplasm.The last 2 decades have seen significant advancements in the management of PFCD.More recently,newer biologics,cell-based therapies,and novel surgical techniques have been introduced in the hope of improved outcomes.However,in refractory cases,many patients face the decision of having a stoma made and/or a proctectomy performed.In this review,we describe modern surgical management and the most recent advances in the management of complex PFCD,which will likely impact clinical practice.

Optimized timing of using infliximab in perianal fistulizing Crohn's disease

Infliximab(IFX),as a drug of first-line therapy,can alter the natural progression of Crohn’s disease(CD),promote mucosal healing and reduce complications,hospitalizations,and the incidence of surgery.Perianal fistulas are responsible for the refractoriness of CD and represent a more aggressive disease.IFX has been demonstrated as the most effective drug for the treatment of perianal fistulizing CD.Unfortunately,a significant proportion of patients only partially respond to IFX,and optimization of the therapeutic strategy may increase clinical remission.There is a significant association between serum drug concentrations and the rates of fistula healing.Higher IFX levels during induction are associated with a complete fistula response in these patients.Given the apparent relapse of perianal fistulizing CD,maintenance therapy with IFX over a longer period seems to be more beneficial.It appears that patients without deep remission are at an increased risk of relapse after stopping anti-tumor necrosis factor agents.Thus,only patients in prolonged clinical remission should be considered for withdrawal of IFX treatment when biomarker and endoscopic remission is demonstrated,especially when the hyperintense signals of fistulas on T2-weighed images have disappeared on magnetic resonance imaging.Fundamentally,the optimal timing of IFX use is highly individualized and should be determined by a multidisciplinary team.

Multidisciplinary and evidence-based management of fistulizing perianal Crohn's disease

Perianal symptoms are common in patients with Crohn's disease and cause considerable morbidity. The etiology of these symptoms include skin tags, ulcers, fissures, abscesses, fistulas or stenoses. Fistula is the most common perianal manifestation. Multiple treatment options exist although very few are evidence-based. The phases of treatment include: drainage of infection, assessment of Crohn's disease status and fistula tracts, medical therapy, and selective operative management. The impact of biological therapy on perianal Crohn's disease is uncertain given that outcomes are conflicting. Operative treatment to eradicate the fistula tract can be attempted once infection has resolved and Crohn's disease activity is controlled. The operative approach should be tailored according to the anatomy of the fistula tract. Definitive treatment is challenging with medical and operative treatment rarely leading to true healing with frequent complications and recurrence. Treatment success must be weighed against the risk of complications, specially anal sphincter injury. A full understanding of the etiology and all potential therapeutic options is critical for success. Multidisciplinary management of fistulizing perianal Crohn's disease is crucial toimprove outcomes.

Application of Three-Dimensional Magnetic Resonance Imaging in the Diagnosis of Perianal Abscess

Perianal abscess is a common disease in anorectal surgery. If the diagnosis is not clear and the cure is thoroughly cleared, the recurrence and spread of anal fistula will cause life-long pain. Objective: To investigate the application of 3.0T MRI 3D CUBE T2WI lipid suppression sequence in the diagnosis of perianal abscess. Methods: Thirty-six patients with perianal abscess confirmed by operation were examined with 2D T2WI and 3D CUBE T2WI lipid suppression sequences before operation. Two imaging techniques were evaluated to show the types of perianal abscess, the number of abscesses, the number of internal orifices of abscess, and the number of fistula branches with anal fistula in abscess. Results: Among 36 cases of perianal abscess, there were 5 cases of anal subcutaneous abscess, 12 cases of ischiorectal space abscess (8 cases complicated with anal fistula), 6 cases of posterior anal space abscess, 5 cases of anal sphincter abscess (3 cases complicated with anal fistula), 2 cases of high intermuscular abscess, 2 cases of rectal submucosal abscess, 3 cases of complex abscess (3 cases complicated with anal fistula), 1 case of misdiagnosis, 2D T2WI lipid suppression sequence and 3D CUBE T2WI suppression. The accuracy of lipid sequence abscess typing was 80.6% (29/36) and 88.9% (32/36), respectively, with no significant difference (P > 0.05). Thirty-six patients were surgically diagnosed as having 32 internal orifices, 68.8% (22/32) and 93.8% (30/32) of 2D T2WI and 3D CUBE T2WI lipid-suppressing sequences, respectively, with significant difference (P Conclusion: 3D CUBE T2WI lipid suppression sequence is superior to 2D T2WI lipid suppression sequence in the classification of perianal abscess, the number of internal orifices of abscess and the number of fistula branches of abscess complicated with anal fistula. It can also determine the number of internal orifices of abscess complicated with anal fistula, the number of fistula branches, the shape of primary and branch fistula and the relationship among pelvic floor muscle tissues. It can provide more accurate images for preoperative and intraoperative clinical surgery.

Perianal infectious dermatitis: An underdiagnosed, unremitting and stubborn condition

Perianal infectious dermatitis(PID) represents a super-ficial inflammation of the perianal skin, which is of bac-terial origin(classically, group A beta-hemolytic strepto-cocci). This narrative review aims to critically review and summarize the available scientific literature regarding pediatric PID, being the first of its kind, to the best of the author's knowledge. It also reports the first cases of Romanian children with PID. Multiple databases were subjected to systematic literature search(from 1966 to April 30, 2018) to identify studies and case reports of children with PID. As such, this review provides up-dated information about essential aspects of PID(epi-demiology, etiology, pathogenesis, as well as clinical features, required investigations and therapeutic options) and of diagnostic pitfalls. Although a well-defined entity, PID remains largely underdiagnosed. PID may mimic other common conditions with skin manifestations(like candidiasis, pinworms, eczema, irritant dermatitis, anal fissure, hemorrhoids, Crohn's disease, psoriasis, sebor-rheic dermatitis, zinc deficiency dermatosis and even sexual abuse), with consequent unnecessary, sometimes expensive and invasive investigations and futile therapies, which cause patients and families discomfort and distress. Since PID has an unremitting course, early recognition is imperative, as it allows for prompt and efficacious antibiotic therapy. However, PID represents a stubborn condition and, even if properly treated, its recurrence rate remains high. Further well-designed prospective randomized controlled trials, with adequate follow-up, are required in order to formulate the optimum personalized antibiotic therapy(oral alone or in association with topical medication), able to prevent recurrences. Awareness of this condition by healthcare professionals should improve patient outcomes.

Magnetic resonance imaging findings for differential diagnosis of perianal plexiform schwannoma: Case report and review of the literature

Plexiform schwannoma is an extremely rare variant of schwannoma, accounting for approximately 5% of cases. Due to the rarity and lack of typical symptoms, signs and radiological images, a definite diagnosis of plexiform schwannoma may not be made by clinicians prior to biopsy. In the present study, we report the first case(to our knowledge) of perianal plexiform schwannoma arising from the overlapped skin of the ischioanal fossa, and we propose an intratumorally nonenhanced circumferential capsule dividing the tumour into multiple homogeneously enhanced nodules as a magnetic resonance imaging feature to aid in the differential diagnosis of plexiform schwannoma from ancient schwannoma, cavernous haemangioma, liposarcoma and plexiform neurofibroma.

Higher infliximab and adalimumab trough levels are associated with fistula healing in patients with fistulising perianal Crohn’s disease

BACKGROUND Tumor necrosis factor-alpha inhibitors,including infliximab and adalimumab,are effective medical treatments for perianal fistulising Crohn’s disease(CD),but not all patients achieve fistula healing.AIM To determine the correlation between perianal fistula healing and closure with infliximab and adalimumab trough levels.METHODS In this multicentre retrospective study conducted across four tertiary inflammatory bowel disease centres in Australia,we identified CD patients with perianal fistulae on maintenance infliximab or adalimumab who had a trough level within twelve weeks of clinical assessment.Data collected included demographics,serum infliximab and adalimumab trough levels(mg/L)within 12 wk before or after their most recent clinical assessment and concomitant medical or surgical therapy.The primary outcome was fistula healing,defined as cessation in fistula drainage.The secondary outcome was fistula closure,defined as healing and closure of all external fistula openings.Differences between patients who did or did not achieve fistula healing were compared using the chi-square test,t test or Mann-Whitney U test.RESULTS One hundred and fourteen patients(66 infliximab,48 adalimumab)were included.Forty-eight(72.7%)patients on maintenance infliximab achieved fistula healing and 18(27.3%)achieved fistula closure.Thirty-seven(77%)patients on maintenance adalimumab achieved fistula healing and 17(35.4%)achieved fistula closure.Patients who achieved fistula healing had significantly higher infliximab and adalimumab trough levels than patients who did not[infliximab:6.4(3.8-9.5)vs 3.0(0.3-6.2)mg/L,P=0.003;adalimumab:9.2(6.5-12.0)vs 5.4(2.5-8.3)mg/L,P=0.004].For patients on infliximab,fistula healing was associated with lower rates of detectable anti-infliximab antibodies and younger age.For patients on adalimumab,fistula healing was associated with higher rates of combination therapy with an immunomodulator.Serum trough levels for patients with and without fistula closure were not significantly different for infliximab[6.9(4.3-10.2)vs 5.5(2.5-8.3)mg/L,P=0.105]or adalimumab[10.0(6.6-12.0)vs 7.8(4.2-10.0)mg/L,P=0.083].CONCLUSION Higher maintenance infliximab and adalimumab trough levels are associated with perianal fistula healing in CD.

Contrast-enhanced computed tomography findings of a huge perianal epidermoid cyst: A case report

BACKGROUND Epidermoid cysts can be found at any location in the human body.However,perianal epidermoid cysts are extremely rare and only a few cases have been reported.As far as we know,there is no special literature on the value of contrast-enhanced computed tomography(CT)for the diagnosis of perianal epidermoid cysts.CASE SUMMARY A 60-year-old male patient presented to the department of general surgery of PLA Strategic Support Force Characteristic Medical Center with the chief complaint of a mass in the perianal region gradually expanding for more than 30 years and perianal discomfort upon sitting for a preceding period of 2 mo.Physical examination revealed a painless mass in the left perianal region.Contrast-enhanced CT was used for preoperative diagnosis.The patient was treated by total mass excision under epidural anesthesia.Postoperative pathological examination revealed the presence of a perianal epidermoid cyst.The patient showed a satisfactory recovery during the 6-month follow-up period.CONCLUSION Contrast-enhanced CT may be a beneficial,useful,and convenient approach for assistance for preoperative diagnosis and surgical decision-making for patients with perianal epidermoid cysts.