Endoscopic and surgical resection of T1a/T1b esophageal neoplasms: A systematic review

AIM: To investigate potential therapeutic recommendations for endoscopic and surgical resection of T1a/ T1b esophageal neoplasms. METHODS: A thorough search of electronic databases MEDLINE, Embase, Pubmed and Cochrane Library, from 1997 up to January 2011 was performed. An analysis was carried out, pooling the effects of outcomes of 4241 patients enrolled in 80 retrospective studies. For comparisons across studies, each reporting on only one endoscopic method, we used a random effects meta-regression of the log-odds of the outcome of treatment in each study. "Neural networks" as a data mining technique was employed in order to establish a prediction model of lymph node status in superficial submucosal esophageal carcinoma. Another data mining technique, the "feature selection and root cause analysis", was used to identify the most impor-tant predictors of local recurrence and metachronous cancer development in endoscopically resected patients, and lymph node positivity in squamous carcinoma (SCC) and adenocarcinoma (ADC) separately in surgically resected patients. RESULTS: Endoscopically resected patients: Low grade dysplasia was observed in 4% of patients, high grade dysplasia in 14.6%, carcinoma in situ in 19%, mucosal cancer in 54%, and submucosal cancer in 16% of patients. There were no significant differences between endoscopic mucosal resection and endoscopic submucosal dissection (ESD) for the following parameters: complications, patients submitted to surgery, positive margins, lymph node positivity, local recurrence and metachronous cancer. With regard to piecemeal resection, ESD performed better since the number of cases was significantly less [coefficient: -7.709438, 95%CI: (-11.03803, -4.380844), P < 0.001]; hence local recurrence rates were significantly lower [coefficient: -4.033528, 95%CI: (-6.151498, -1.915559),P < 0.01]. A higher rate of esophageal stenosis was observed following ESD [coefficient: 7.322266, 95%CI: (3.810146, 10.83439), P < 0.001]. A significantly greater number of SCC pa     

Endoscopic tools for the diagnosis and evaluation of celiac disease

Celiac disease(CD)is an autoimmune disease of the small bowel induced by ingestion of wheat,rye and barley.Current guidelines indicate histological analysis on at least four duodenal biopsies as the only way to diagnose CD.These indications are based on the conception of the inability of standard endoscopy to make diagnosis of CD and/or to drive biopsy sampling.Over the last years,technology development of endoscopic devices has greatly ameliorated the accuracy of macroscopic evaluation of duodenal villous pattern,increasing the diagnostic power of endoscopy of CD.The aim of this paper is to review the new endoscopic tools and procedures proved to be useful in the diagnosis of CD,such as chromoendoscopy,Fujinon Intelligent Chromo Endoscopy,Narrow Band Imaging,Optical Coherence Tomography,Water-Immersion Technique,confocal laser endomicroscopy,high-resolution magnification endoscopy,capsule endoscopy and I-Scan technology.     

肠道微生态影响动脉粥样硬化发生发展的机制

动脉粥样硬化(AS)不仅是一种炎症性疾病,而且属于一种代谢性疾病。肠道微生态的改变可对AS的发生发展产生双面影响。一方面,肠道菌群紊乱可以通过影响机体的胆碱代谢、氧化应激、炎症反应等机制直接促进AS产生发展,此外,可通过导致AS危险因素肥胖、高脂血症、糖尿病等的产生这些间接机制促AS的进展。另一方面,益生菌及益生元的增加则可有效地降低肠道微生物内毒素产生、增强肠道屏障、减轻机体质量、缓解炎症反应、改善胰岛素抵抗,进而在AS的进展方面发挥重要作用。因此,合理调控机体肠道微生态环境成为AS防治的新型重要手段。     

Neoadjuvant radiotherapy for rectal cancer management

Thirty per cent of all colorectal tumours develop in the rectum.The location of the rectum within the bony pelvis and its proximity to vital structures presents significant therapeutic challenges when considering neoadjuvant options and surgical interventions.Most patients with early rectal cancer can be adequately managed by surgery alone.However,a significant proportion of patients with rectal cancer present with locally advanced disease and will potentially benefit from down staging prior to surgery.Neoadjuvant therapy involves a variety of options including radiotherapy,chemotherapy used alone or in combination.Neoadjuvant radiotherapy in rectal cancer has been shown to be effective in reducing tumour burden in advance of curative surgery.The gold standard surgical rectal cancer management aims to achieve surgical removal of the tumour and all draining lymph nodes,within an intact mesorectal package,in order to minimise local recurrence.It is critically important that all rectal cancer cases are discussed at a multidisciplinary meeting represented by all relevant specialties.Pre-operative staging including CT thorax,abdomen,pelvis to assess for distal disease and magnetic resonance imaging to assess local involvement is essential.Staging radiology and MDT discussion are integral in identifying patients who require neoadjuvant radiotherapy.While Neoadjuvant radiotherapy is potentially beneficial it may also result in morbidity and thus should be reserved for those patients who are at a high risk of local failure,which includes patients with nodal involvement,extramural venous invasion and threatened circumferential margin.The aim of this review is to discuss the role of neoadjuvant radiotherapy in the management of rectal cancer.     

Quality of life after laparoscopic vs open sphincter-preserving resection for rectal cancer

AIM: To compare quality of life (QoL) outcomes in Chinese patients after curative laparoscopic vs open surgery for rectal cancer. METHODS: Eligible Chinese patients with rectal cancer undergoing curative laparoscopic or open sphincterpreserving resection between July 2006 and July 2008 were enrolled in this prospective study. The QoL outcomes were assessed longitudinally using the validated Chinese versions of the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQCR38 questionnaires before surgery and at 4, 8, and 12 mo after surgery. The QoL scores at the different time points were compared between the laparoscopic and open groups. A higher score on a functional scale indicated better functioning, whereas a higher score on a symptom scale indicated a higher degree of symptoms.RESULTS: Seventy-four patients (49 laparoscopic and 25 open) were enrolled. The two groups of patients were comparable in terms of sociodemographic data, types of surgery, tumor staging, and baseline mean QoL scores. There was no significant decrease from baseline in global QoL for the laparoscopic group at different time points, whereas the global QoL was worse compared to baseline beginning at 4 mo but returned to baseline by 12 mo for the open group (P = 0.019, Friedman test). Compared to the open group, the laparoscopic group had significantly better physical (89.9±1.4 vs 79.2±3.7, P = 0.016), role (85.0±3.4 vs 63.3±6.9, P = 0.005), and cognitive (73.5±3.4 vs 50.7±6.2, P = 0.002) functioning at 8 mo, fewer micturition problems at 4-8 mo (4 mo: 32.3±4.7 vs 54.7±7.1, P = 0.011; 8 mo: 22.8±4.0 vs 40.7±6.9, P = 0.020), and fewer male sexual problems from 8 mo onward (20.0±8.5 vs 76.7±14.5, P = 0.013). At 12 mo after surgery, no significant differences were observed in any functional or symptom scale between the two groups, with the exception of male sexual problems, which remained worse in the open group (29.2±11.3 vs 80.0±9.7, P = 0.026). CONCLUSION: Laparoscopic sphincter-preserving resection for rec     

Endoscopic Kyoto classification of Helicobacter pylori infection and gastric cancer risk diagnosis

Recent advances in endoscopic technology allow detailed observation of the gastric mucosa.Today,endoscopy is used in the diagnosis of gastritis to determine the presence/absence of Helicobacter pylori(H.pylori)infection and evaluate gastric cancer risk.In 2013,the Japan Gastroenterological Endoscopy Society advocated the Kyoto classification,a new grading system for endoscopic gastritis.The Kyoto classification organized endoscopic findings related to H.pylori infection.The Kyoto classification score is the sum of scores for five endoscopic findings(atrophy,intestinal metaplasia,enlarged folds,nodularity,and diffuse redness with or without regular arrangement of collecting venules)and ranges from 0 to 8.Atrophy,intestinal metaplasia,enlarged folds,and nodularity contribute to gastric cancer risk.Diffuse redness and regular arrangement of collecting venules are related to H.pylori infection status.In subjects without a history of H.pylori eradication,the infection rates in those with Kyoto scores of 0,1,and≥2 were 1.5%,45%,and 82%,respectively.A Kyoto classification score of 0 indicates no H.pylori infection.A Kyoto classification score of 2 or more indicates H.pylori infection.Kyoto classification scores of patients with and without gastric cancer were 4.8 and 3.8,respectively.A Kyoto classification score of 4 or more might indicate gastric cancer risk.     

Totally laparoscopic left hepatectomy using the Torsional Ultrasonic Scalpel

Minimal invasive techniques have allowed for major surgical advances.We report our initial experience of performing total laparoscopic left hepatectomy(segmentsⅡ-Ⅳ)with the Lotus(laparoscopic operation by torsional ultrasound)Ultrasonic Scalpel.The perioperative and postoperative courses of the young female patient were uneventful and she is in a good general condition without complaints 18 mo after surgery.To the best of our knowledge,this is the first total laparoscopic hemihepatectomy to be performed in Greece,as well as the first laparoscopic liver resection using Lotus shears.     

Contribution of pancreatic enzyme replacement therapy to survival and quality of life in patients with pancreatic exocrine insufficiency

The objective of this study was to analyze the current evidence for the use of pancreatic enzyme replacement therapy (PERT) in affecting survival and quality of life in patients with pancreatic exocrine insufficiency (PEI). Systematic searches of the literature were performed using the PubMed database. Articles were selected for inclusion if they reported findings from trials assessing the effects of PERT on quality of life, survival, malabsorption, growth parameters (such as height, body weight and body mass index), or gastrointestinal symptoms (such as abdominal pain, stool consistency and flatulence). PERT improved PEI-related malabsorption and weight maintenance in patients with cystic fibrosis, chronic pancreatitis, pancreatic cancer, and post-surgical states. In patients with chronic pancreatitis, PERT improved PEI-related symptoms and quality of life measures. Several small retrospective studies have also suggested that PERT may have a positive impact on survival, but long-term studies assessing this effect were not identified. PERT is effective for treating malnutrition and supporting weight maintenance, and it is associated with improved quality of life and possibly with enhanced survival in patients with PEI. However, there is evidence that not all patients with PEI receive adequate PERT. Future work should aim to assess the long-term effects of PERT on the survival of patients with PEI.     

PNPLA3 I148M polymorphism and progressive liver disease

The 148 Isoleucine to Methionine protein variant(I148M)of patatin-like phospholipase domain-containing 3(PNPLA3),a protein is expressed in the liver and is involved in lipid metabolism,has recently been identified as a major determinant of liver fat content.Several studies confirmed that the I148M variant predisposes towards the full spectrum of liver damage associated with fatty liver:from simple steatosis to steatohepatitis and progressive fibrosis.Furthermore,the I148M variant represents a major determinant of progression of alcohol related steatohepatitis to cirrhosis,and to influence fibrogenesis and related clinical outcomes in chronic hepatitis C virus hepatitis,and possibly chronic hepatitis B virus hepatitis,hereditary hemochromatosis and primary sclerosing cholangitis.All in all,studies suggest that the I148M polymorphism may represent a general modifier of fibrogenesis in liver diseases.Remarkably,the effect of the I148M variant on fibrosis was independent of that on hepatic steatosis and inflammation,suggesting that it may affect both the quantity and quality of hepatic lipids and the biology of non-parenchymal liver cells besides hepatocytes,directly promoting fibrogenesis.Therefore,PNPLA3 is a key player in liver disease progression.Assessment of the I148M polymorphism will possibly inform clinical practice in the future,whereas the determination of the effect of the 148M variant will reveal mechanisms involved in hepatic fibrogenesis.     

Post-translational modifications of hepatitis C viral proteins and their biological significance

Replication of hepatitis C virus(HCV)depends on the interaction of viral proteins with various host cellular proteins and signalling pathways.Similar to cellular proteins,post-translational modifications(PTMs)of HCV proteins are essential for proper protein function and regulation,thus,directly affecting viral life cycle and the generation of infectious virus particles.Cleavage of the HCV polyprotein by cellular and viral proteases into more than 10 proteins represents an early protein modification step after translation of the HCV positivestranded RNA genome.The key modifications include the regulated intramembranous proteolytic cleavage of core protein,disulfide bond formation of core,glycosylation of HCV envelope proteins E1 and E2,methylation of nonstructural protein 3(NS3),biotinylation of NS4A,ubiquitination of NS5B and phosphorylation of core and NS5B.Other modifications like ubiquitination of core and palmitoylation of core and NS4B proteins have been reported as well.For some modifications such as phosphorylation of NS3 and NS5A and acetylation of NS3,we have limited understanding of their effects on HCV replication and pathogenesis while the impact of other modifications is far from clear.In this review,we summarize the available information on PTMs of HCV proteins and discuss their relevance to HCV replication and pathogenesis.     

Anal manometric findings in symptomatic hemorrhoids

Anal manometric findings were studied in 50 patients with symptomatic hemorrhoids and an equal number of age- and sex-matched control subjects. Manometry was performed with a continuously perfused catheter by the continuous pull-through technique. Both the control subjects and patients had significant negative collerations between age and basal pressure;i.e., basal pressure was lower with advancing age. Patients with symptomatic hemorrhoids had significantly higher maximal basal pressure (P<0.02) and maximal voluntary contraction pressure (P<0.05) as compared to controls. There was no correlation between the anal manometric findings and the degree of hemorrhoids or duration of symptoms. Those patients who had bleeding as the predominant symptom had higher basal pressures; (P<0.05) than those who had prolapsing hemorrhoids as the predominant symptom.     

Tumor Site Predicts Outcome After Radiochemotherapy in Squamous-Cell Carcinoma of the Anal Region: Long-Term Results of 101 Patients

PURPOSE This study was designed to assess the long-term results following radiochemotherapy in patients with anal squamous-cell carcinoma and to evaluate the impact of tumor location on response, survival, and colostomy-free survival.PATIENTS AND METHODS Between 1985 and 2001, a total of 101 patients with anal carcinoma were registered for curative treatment, of whom 77 had involvement of the anal canal alone, 10 cases had extension into the perianal skin, and 14 patients had pure anal margin tumors. Small tumors of the anal margin were not included since they were treated by surgical excision only. Among the 101 patients were 74 women and 27 men with a median age of 62 (range, 26–84) years. T categories (International Union against Cancer) were T1 (15), T2 (36), T3 (34), and T4 (16). Seventy-one patients had no evidence of nodal disease, whereas 30 presented with involved regional nodes. Radiation treatment was directed to the primary tumor region and to the inguinal, perirectal, and internal iliac nodes using a three-field to four-field box technique with 10MV photons up to a total dose of 5040 cGy. Lesions greater than 5 cm received an additional boost by interstitial or external radiation depending on circumferential extension of the residual tumor. All patients were scheduled for simultaneous chemotherapy with two cycles of 5-fluorouracil at a dose of 1000 mg/m ²/day as 120 hours of continuous intravenous infusion on Days 1 to 5 and 29 to 33 and mitomycin C at 10 mg/m ²/day on Days 1 and 29. Median follow-up time was was 7.5 (range, 1–16) years.RESULTS Overall survival and colostomy-free survival rates for patients with anal canal cancer were 75 percent and 87 percent at five years, respectively. Patients with anal margin cancer had a less favorable outcome with five-year-overall and colostomy-free survival rates of 54 percent and 69 percent, respectively. After correction for imbalance between anal canal and anal margin tumors, i.e., exclusion of T1 tumors of the anal canal, difference in overall survival remained significant (73 percent vs. 54 percent, P = 0.01). Following multivariate analysis, tumor location (anal canal vs. anal margin, P = 0.02), age (P = 0.003), and dose intensity of chemotherapy (≤75 percent vs. >75 percent, P = 0.03) remained independent significant factors for overall survival. Initial tumor response at six weeks (P = 0.03) was predictive for colostomy-free survival.CONCLUSIONS With colostomy-free survival rates around 85 percent, long-term treatment results for anal canal carcinoma have reached a satisfactory level. However, patients with larger lesions of the perianal skin are at high risk for locoregional recurrence and possible treatment intensification in this subgroup seems desirable.Supported by Grant No. D 15 from the Interdisciplinary Center for Clinical Research of the Medical Faculty of the University of Erlangen-Nuremberg.Presented at the meeting of the American Society for Therapeutic Radiology and Oncology, Denver, Colorado, October 16 to 20, 2005.     

The external anal sphincter

Anal manometry and anal electromyography (EMG) were performed in 45 patients to evaluate the external anal sphincter. Their symptoms were soiling (N=6), incontinence (N=10), and obstipation (N=10). Clinical diagnoses were previous anal surgery (N=16), rectal prolapse—partial, total, intussusception (N=16), puborectalis syndrome (N=4), neurologic disorders (N=3), and others (N=6). The relationship between the maximum squeeze pressure (MSP) measured with anal manometry and the maximum (voluntary) contraction pattern (MCP) and signs of denervation (DEN) measured with anal EMG were examined. The correlation coefficient between MSP and MCP was 0.55 (P<.001) and between MSP, and DEN 0.13 (NS). A normal MSP always showed a normal MCP, a normal MCP showed an abnormal MSP in 43 percent only. In conclusion, the clinical value of anal EMG seems limited. Assessment of an additional anal EMG seems indicated in incontinent patients with previous anal surgery with a low MSP to estimate muscle function, whenever anal surgery is considered. Anal EMG during straining can easily confirm the clinical diagnosis of puborectalis syndrome. Presented in part at the meeting of the Dutch Society of Gastroenterology, Noordwijkerhout, The Netherlands, October 2–3, 1987.     

Infiltrating adenocarcinoma arising in a villous adenoma of the anal canal

Primary neoplasms arising in the anal canal are relatively unusual. In particular, adenomas and adenocarcinomas are distinctly rare entities in this region. We describe an infiltrating, well-differentiated adenocarcinoma arising in a villous adenoma from the distal anal canal, in an otherwise healthy patient at low risk for gastrointestinal malignancy. This is the case of an octogenarian man with a several year history of hemorrhoids and intermittent rectal bleeding, more recently complaining of continuous hematochezia. Examination revealed a blood-covered pedunculated mass with a long stalk protruding from the anus. The lesion was amputated at the bedside. Microscopic evaluation revealed an infiltrating well-differentiated adenocarcinoma, arising from a villous adenoma. This was further evaluated under anesthesia and complete excision of distal anal tissue was performed. Our report is the first describing the possible malignant degeneration of a villous adenoma in the anal canal.     

Anal cancer in renal transplant patients

Purpose A comprehensive literature review was performed to examine the prevalence of anal cancer, anal intraepithelial neoplasia (AIN) and anal human papillomavirus (HPV) infection in renal transplant recipients who are at risk of anal cancer due to iatrogenic immunosuppression.Methods Pertinent articles were identified from searches performed on the National Center for Biotechnology Information database using the following keywords: anal cancer, AIN, screening, renal transplant (or kidney transplant), organ transplant recipients and post-transplant malignancies.Results The prevalence of AIN is 20% in renal transplant patients. The prevalence of anal HPV infection in established transplant patients is 47%, and the prevalence of anal HPV infection in new transplant patients is 23%. The relative risk for anal cancer in renal transplant patients is 10.Conclusions As compared to HIV-positive male patients who practise anal intercourse, renal transplant patients showed a modest rise in relative risk for anal cancer. Screening programmes to detect AIN in HIV-positive patients who practise anal intercourse have been introduced on a preliminary basis in sexual health clinics in the US and may become standard practise in this population. The case for screening in renal transplant patients is unclear and would merit further investigation, especially with reference to the prevalence of anal HPV infection in this population. It may transpire that renal transplant patients would benefit more from HPV prophylaxis rather than screening for AIN.     

Patient satisfaction and symptom relief after anal dilatation

Anal dilatation is used as a simple method of treatment and has been used for both anal fissure and haemorrhoids. This study examined longer-term results among a cohort of 162 patients, 132 of whom responded to a detailed questionnaire, an 82% response (66 patients were male; age range 17–75 years, median 42 years). Follow-up ranged from 16 months to 36 months (median 27 months) after anal dilatation (68 patients for fissure, 32 for haemorrhoids, and 32 for both). In the early months after dilatation, 83% had symptomatic improvement and 76% remained improved. Five (7%) patients with fissure and 11 with haemorrhoids (17%) required further hospital treatment, while 10% and 17%, respectively, had received further treatment from their general practitioners (GPs). Seventy-one percent said they would have a further anal dilation if symptoms recurred. There was no difference in results obtained by surgeons of different seniority. Complications – bleeding (29%) and difficulty controlling flatus (15%) or faeces (8%) – resolved in all cases. The results of anal dilatation for fissure are generally satisfactory in the longer term, with a trend toward better symptom relief in patients with fissure compared with those with haemorrhoids. We do not recommend anal dilatation as the sole treatment of patients with haemorrhoids, but it may be a useful adjunct to other treatments such as banding or sclerotherapy. Morbidity was generally acceptable and the majority of our patients would be prepared to have this procedure again if their symptoms were to return. Accepted: 14 September 1998     

A study to determine the nitroglycerin ointment dose and dosing interval that best promote the healing of chronic anal fissures

PURPOSE: The aim of this study was to determine the optimal dose and dosing interval of nitroglycerin ointment to heal chronic anal fissures. METHOD: A randomized, double-blind study of intra-anally applied nitroglycerin ointment (Anogesic) was conducted in 17 centers in 304 patients with chronic anal fissures. The patients were randomly assigned to one of eight treatment regimens (0.0, 0.1, 0.2, 0.4 percent nitroglycerin ointment applied twice or three times per day), for up to eight weeks. A dose-measuring device standardized the delivery of 374 mg ointment. Healing of fissures (complete reepithelialization) was assessed by physical examination using an observer unaware of treatment allocation. The subjects assessed pain intensity daily by completing a diary containing a visual analog scale for average pain intensity for the day, the worst pain intensity for the day, and pain intensity at the last defecation. RESULTS: There were no significant differences in fissure healing among any of the treatment groups; all groups, including placebo had a healing rate of approximately 50 percent. This rate of placebo response was inexplicably higher than previously reported in the literature. Treatment with 0.4 percent (1.5 mg) nitroglycerin ointment was associated with a significant (P < 0.0002) decrease in average pain intensity compared with vehicle as assessed by patients with a visual analog scale. The decreases were observed by Day 4 of treatment. At 8 weeks the magnitude of the difference between 0.4 percent nitroglycerin and control was a 21 percent reduction in average pain. Treatment was well tolerated, with only 3.29 percent of patients discontinuing treatment because of headache. Headaches were the primary adverse event and were dose related. CONCLUSION: Nitroglycerin ointment did not alter healing but significantly and rapidly reduced the pain associated with chronic anal fissures.     

Keratoacanthoma of the anus

Three cases of keratoacanthomas localized to the anal region are reported-one in the anal canal and two at the anal margin. The duration of the tumors before treatment was very short (three to nine weeks). Treatment consisted of local excision or curettage and electrocaagulation. No recurrence of the tumors was found at follow-up four to six years after treatment.     

Endoanal ultrasound in perianal fistulas and abscesses

Anal ultrasound has demonstrated to be accurate in staging perianal cryptoglandular fistulae and fistulae in Crohn's disease. When there is an external fistula opening, H2O2 can be introduced with a plastic infusion catheter. The tract becomes then visible as a hyperechoic lesion ('white'). It has been shown that this corresponds excellent with surgical findings. It is equally sensitive as endoanal MRI. Because recurrent cryptoglandular fistulae are complex in about 50% and Crohn's fistula in 75%, it is mandatory to perform anal ultrasound preoperative in these patients to avoid missed tracks during surgery and subsequent recurrences. Anal ultrasound can also be used to monitor (medical) therapy in patients with Crohn's disease. Especially considering the easiness of performing and lesser costs then MRI, endoanal ultrasound merits more attention.     

Does HIV status influence the anatomy of anal fistulas?

PURPOSE: Although anorectal disease is common in human immunodeficiency virus-positive patients, little is known about the type and anatomic distribution of anal fistulas in this patient group. The aim of this study was to compare anatomic characteristics of anal fistulas in human immunodeficiency virus-positive patients with those in human immunodeficiency virus-negative patients by use of a retrospective chart review. METHODS: The charts of 146 male patients younger than 50 years with an anal fistula were reviewed. Incomplete fistulas referred to those tracts arising from an internal opening into either a blind sinus or an undrained abscess cavity. RESULTS: There were 60 human immunodeficiency virus-positive patients and 86 human immunodeficiency virus-negative patients. Mean age of the human immunodeficiency virus-positive patient group was 37 yearsvs. 40 years for the human immunodeficiency virus-negative patient group. Thirty-one human immunodeficiency virus-positive patients (52 percent) were classified as having AIDS, and the remaining 29 patients (48 percent) were asymptomatic. Mean T helper cell count in the human immunodeficiency virus-positive patient group was 277 cells per microliter. Fistulous tracts were intersphincteric (n=56), transsphincteric (n=41), suprasphincteric (n=2), and incomplete (n=47). Incomplete fistulas were identified in 33 (55 percent) human immunodeficiency virus-positive patientsvs. 14 (16 percent) human immunodeficiency virus-negative patients (P<0.001). Of the 47 incomplete fistulas, 37 (79 percent) were found in association with an abscess cavity. All ten patients with an incomplete fistula into a blind sinus were human immunodeficiency virus-positive. The incidence of an incomplete fistula without an abscess was significantly higher in the human immunodeficiency virus-positive patient group (17 percent) compared with the human immunodeficiency virus-negative patient group (0 percent;P<0.001). CONCLUSIONS: Anal fistulas in HIV-positive patients arise from the dentate line in similar locations to human immunodeficiency virusnegative patients. However, human immunodeficiency virus-positive patients were more likely to have incomplete anal fistulas than human immunodeficiency virus-negative patients. Furthermore, human immunodeficiency virus-positive patients are predisposed to incomplete fistulas leading into a blind sinus.Read at the meeting of The Southern California Chapter of the American College of Surgeons, Dana Point, California, January 17 to 19, 1997.