You are in: eMedicine Specialties > General Surgery > Colorectal Perianal GranulomaArticle Last Updated: Aug 3, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Carol E H Scott-Conner, MD, PhD, Professor, Department of Surgery, University of Iowa College of Medicine Carol E H Scott-Conner is a member of the following medical societies: American Association for Cancer Research, American Association for the Surgery of Trauma, American Burn Association, American Cancer Society, American College of Gastroenterology, American College of Surgeons, American Medical Association, American Society for Gastrointestinal Endoscopy, Association for Academic Surgery, Association for Surgical Education, Association of VA Surgeons, Iowa Medical Society, Sigma Xi, Society for Surgery of the Alimentary Tract, Society of American Gastrointestinal and Endoscopic Surgeons, Society of Critical Care Medicine, Society of Surgical Oncology, Society of University Surgeons, and Southeastern Surgical Congress Coauthor(s): Jan Rakinic, MD, Chief, Section of Colorectal Surgery, Southern Illinois University Editors: Juan B Ochoa, MD, Assistant Professor, Department of Surgery, University of Pittsburgh; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Michael A Grosso, MD, Consulting Staff, Department of Cardiothoracic Surgery, St Francis Hospital; Paolo Zamboni, MD, Professor of Surgery, Chief of Day Surgery Unit, Chair of Vascular Diseases Center, University of Ferrara, Italy; John Geibel, MD, DSc, MA, Professor, Department of Surgery, Section of Gastrointestinal Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine; Director of Surgical Research, Department of Surgery, Yale-New Haven Hospital Author and Editor Disclosure Synonyms and related keywords: Crohn disease, Crohn's disease, perianal granulomatous disease, perianal abscess, perianal fistula, perianal fissure, tubercular perianal disease, anorectal tuberculosis, anorectal TB, Actinomyces, Basidiobolus, basidiobolomycosis, actinomycosis, lymphogranuloma venereum, schistosomiasis, amebiasis, granuloma pyogenicum INTRODUCTIONSection 2 of 12
  Perianal granulomas present some degree of diagnostic difficulty. Crohn disease is the most common cause of perianal granulomatous disease in the Western world. Elsewhere, incidence of non-Crohn perianal granuloma varies, but it may be more common than in the United States. For excellent patient education resources, visit eMedicine's Esophagus, Stomach, and Intestine Center and Crohn Disease Center. Also, see eMedicine's patient education articles, Crohn Disease, Inflammatory Bowel Disease, and Anal Abscess. History of the ProcedureThe various procedures used in the surgical treatment of perianal granulomatous disease are largely those also used in the treatment of perianal abscess and fistula. ProblemA spectrum of diseases can produce granulomas of the perianal region and perineum. Most are infectious or inflammatory. Standard histologic diagnosis often does little to clarify the etiology. FrequencyThe prevalence of Crohn disease is estimated at 3-5 cases per 100,000 persons in most areas of the world. Prevalence is less in African Americans than in whites and is quite rare in most Asian populations. Tubercular perianal disease is also rare, clearly comprising less than 10% of all perianal disease and 0.7% of all tuberculosis (TB) cases. The incidence will vary with the incidence of tuberculosis in the overall population. The remaining causes of perianal granulomatous disease are extremely rare. EtiologyThe following causes of perianal granuloma are reported in the medical literature. This list is not meant to be exhaustive. Crohn disease is by far the most common cause, followed by TB and actinomycosis, both of which must be considered in the evaluation of the perianal fistula or fissure that does not heal or that recurs after appropriate treatment.
PathophysiologyThe cause of Crohn disease is not yet known. An infectious etiology is thought to be responsible, as are alterations in the immune response. Granulomas in Crohn disease have been postulated to represent an adaptive mechanism for removal or localization of the causative agent because patients with a long clinical history show fewer granulomas than those with a shorter clinical history. The granulomas of Crohn disease may be sarcoid-type or nonspecific. Anorectal TB often manifests as complex fistulous disease that has failed initial surgical therapy. Chest radiography helps to narrow the diagnosis (see Clinical). Most cases of anorectal TB are primary presentations, although secondary infection of the pilonidal sinus has been reported. Actinomyces is a normal fungal inhabitant of the GI tract that has been sporadically reported to cause clinically evident GI infections. Basidiobolus has also been reported to cause various GI infections much less frequently. Schistosomiasis can produce genital and perigenital granulomas during the oviposition stage. Perianal amebiasis is usually associated with GI infection. Inoculation of the organisms directly into a wound or abraded skin can occur and may lead to formation of abscesses, fistulas, and ulcers. These may progress rapidly and destroy perianal tissues. The responsible organism should be sought in sigmoidoscopy specimens and biopsies from the ulcer edge. Lymphogranuloma venereum is a vegetating, scarring lesion caused by Chlamydia trachomatis. It commonly causes rectal stenosis and can produce sinuses in the perianal region that must be differentiated from actinomycosis and hidradenitis. ClinicalClinical presentation may vary widely from asymptomatic with minimal physical signs to recurrent or persistent problems that are very distressing. Disease presentation may range from an asymptomatic nodule to a simple fistula or a draining sinus to the complex presentations of multiple, draining fistulas or sinuses and wide involvement with undermining of previously normal tissues. In about 9% of patients with Crohn disease, anorectal manifestations are the first indication of the disease. The lesions are usually abscesses or fistulas and may be solitary or multiple, simple or complex. Evaluation of the GI tract usually reveals evidence of Crohn disease elsewhere. Crohn fistulae may look relatively indolent (see Media file 1) compared to the more typical chronic fistulo-in-ano. Approximately 10% of patients with anorectal TB have active pulmonary TB as well and nearly all of the remainder have evidence of old pulmonary TB on chest x-ray films. The diagnosis of tubercular anorectal disease should be considered whenever anorectal fistulas or abscesses heal poorly or recur after initial therapy. The remainder of causes are clarified with the help of tissue biopsies for histopathologic, serologic, and other special testing. INDICATIONSSection 3 of 12
Surgical intervention is predicated on presentation. If symptoms are related to fistulous disease, procedures for fistulas may be considered. For symptomatic granulomas, excision may be chosen. RELEVANT ANATOMYSection 4 of 12
Location of the anal sphincters and evaluation of their function is a key part of patient evaluation. Fistulous tracts must be evaluated for their relationship to the sphincters. The number of external fistulous openings and their location convey information about possible etiology. Multiple external openings are probably due to Crohn disease or one of the other etiologies listed earlier rather than to cryptoglandular disease of the anorectum. All of these etiologies can produce multiple draining sinuses or fistulas with a surprising amount of tissue destruction. The amount of scarring and verrucosity varies. Knowledge of the anatomy of the male and female perineal floor as well as perianal anatomy is required of the surgical specialist treating complications of perianal granulomatous disease. If the inflammatory process extends anteriorly, consultation with urologic or gynecologic specialists can be invaluable. CONTRAINDICATIONSSection 5 of 12
For contraindications regarding surgical approach, see Surgical therapy. WORKUPSection 6 of 12
Lab Studies
Imaging Studies
Other Tests
Diagnostic Procedures
Histologic FindingsRegular histopathology should always be requested on tissue specimens. The presence of so-called sulfur granules is characteristic of Actinomyces. Granulomas, caseating or noncaseating, may be observed, although this is more rare in Crohn disease than commonly believed. Other infectious agents may be identified with histopathology (eg, fungi, parasites). TREATMENTSection 7 of 12
Medical therapyMedical therapy directed at the causative factor is usually started following disease recurrence after several trials of surgical treatment. Specific medical therapy depends upon the etiology defined. Antitubercular therapy is instituted for tubercular causes, usually with 3-4 drugs for a prolonged course of therapy and also treating pulmonary disease, if present. The causative organisms often display resistance to multiple drugs. Antifungals are used when a fungus is believed to be the etiology. The specific drug depends on the fungus identified. Tetracyclines remain the treatment of choice for lymphogranuloma venereum. The surgical treatment of this condition is particularly difficult because of the degree of tissue destruction often observed in long-standing cases. Surgical therapySurgical therapy is very straightforward. Esoteric causes are not sought until after the disease has recurred, sometimes after several surgical procedures. Abscesses should be drained. Fistulas are treated appropriately, depending upon fistula anatomy. Simple fistulas, involving little or no sphincter muscle, may be treated with simple lay-open fistulotomy techniques. On the other hand, complex or unusual fistulas at most should be drained until the anatomy can be elucidated. Simple granulomas may be excised with the skin left open to close by secondary intention. Lymphogranuloma venereum especially can cause extensive tissue destruction, sometimes destroying the rectovaginal septum and leaving the patient with a cloacallike abnormality. Reconstruction in this setting can be exceedingly difficult, considering the rectum and often the sigmoid are also abnormal, thus making diversion with an end colostomy the only option. HIV testing should be considered. Preoperative detailsKnowledge of the correct diagnosis greatly increases the likelihood that surgical therapy will be successful in perianal granulomatous disease. Since the diagnosis is often not considered until disease is advanced or has recurred, surgeons must endeavor to maintain a high index of clinical awareness whenever a presentation seems unusual. Intraoperative detailsUnusual lesions should be generously biopsied, not necessarily excised, because this may not be necessary when the etiology is known. Pus must be drained, taking care to preserve sphincter function and continence. If unforeseen extensive fistulous tracts are found, simple drainage is the correct action, with postoperative investigation of the anatomy using MRI, endorectal or endoanal ultrasound, or both. Postoperative detailsNonhealing or recurrence after an otherwise simple perianal operative procedure must prompt evaluation of causes other than cryptoglandular disease of the anorectum, sebaceous cysts, or pilonidal disease. Crohn disease is always prominent in the differential diagnosis, and TB is becoming so. Follow-upWounds are cared for as after any anorectal surgical procedure: with damp-to-dry dressings of isotonic sodium chloride solution, avoidance of constipation and diarrhea, and careful cleansing of the region. Granulation may be slow in the patient who is immunocompromised. On occasion, sharp debridement may be needed. If the wound is granulating poorly, switching from isotonic sodium chloride solution to a quarter-strength Dakin solution for 5-10 days can be helpful. Betadine should not be used for dressings because it retards healing. COMPLICATIONSSection 8 of 12
Aside from recurrence, which may occur until identification of the true etiology, the complications are chiefly those of any anorectal surgical procedure. However, patients may undergo multiple procedures before the cause is identified, and the underlying etiology may cause anatomic changes in the perianal region as well. Because of this, these patients are at higher risk for complications such as sphincter dysfunction with impaired continence, stenosis, mucosal ectropion, and rectovaginal fistula. These patients also bear the morbidity associated with the underlying etiology. Some of them may also be immunocompromised. OUTCOME AND PROGNOSISSection 9 of 12
Prognosis depends upon the degree of anatomic changes, whether postsurgical or directly due to the underlying disease, and the ability to treat the causative problem. The latter includes the intrinsic toxicity of therapy, which for many of the infectious agents discussed here, is significant. The noncompliant patient presents another facet of prognosis. The therapy for many of these unusual diseases can be lengthy and can cause unpleasant adverse effects. A great deal of family or community support may be needed for these individuals to accept and complete therapy. FUTURE AND CONTROVERSIESSection 10 of 12
Incidence of perianal granuloma of non-Crohn disease etiology seems to be increasing worldwide, albeit more slowly in the West than in the developing world. Many of the infectious agents responsible are resistant to conventional therapy. Early diagnosis is nearly unknown. This group of diseases should be considered in the differential diagnosis whenever an unusual lesion is found in the perianal region or when no response occurs to conventional surgical treatment. MULTIMEDIASection 11 of 12
REFERENCESSection 12 of 12
Article Last Updated: Aug 3, 2006 | ||||||||||||||
