Anal and Rectal Disorders 2024-02 PDF

Anal and rectal disorders  Resources (Exam focus) Pathophysiology - Histopathology Clinical setting Anatomy: Rectum Anatomy: Annus  Innervation Internal anal sphincter: Extrinsi...

Anal and rectal disorders  Resources (Exam focus) Pathophysiology - Histopathology Clinical setting Anatomy: Rectum Anatomy: Annus  Innervation Internal anal sphincter: Extrinsic autonomic fibers (of both the sympathetic and parasympathetic nervous systems). External anal sphincter: The pudendal nerve (sacral nerve roots S2, S3 and S4). Rectum: the sympathetic nervous system via the pelvic plexus (L1, L2, and L3) + the parasympathetic nervous system via the nervi erigentes (S2, S3, and S4). The World Society of Emergency Surgery (WSES) guidelines for the management of severe acute pancreatitis. 2019. Advances in acute pancreatitis. Co-critical Care Review. 2021 Wolters Kluwer Health, Inc Infectious disorders of the annus and rectum  Chlamydia and Lymphogranuloma venereum Organism Chlamydia trachomatis. Serovars D–K cause sexually transmitted urethritis and anorectal infections, and serovars L1–L3 cause lymphogranuloma venereum. Epidemiology C. trachomatis infection is the most common sexually transmitted disease in the United States, and LGV is 20 times more common in men than in women. Patients at risk: African-Americans, patients infected with HIV, and other individuals at risk of contracting venereal diseases, for example, people with multiple sex partners or who are immunocompromised. Symptoms: marked inguinal adenopathy (buboes) with fever, chills. Late stages are characterized by rectal or colorectal involvement (proctitis and colitis), and rectovaginal fistulas. Pathophysiology: abscesses, and granuloma formation. Ulceration is seen on endoscopy. Diagnostic; sigmoidoscopy, biopsies, rectal culture, and microimmunofluorescent antibody or complement fixation testing. Treatment: Patients should be empirically treated for gonococcal proctitis if they are diagnosed with chlamydial proctitis. Sexual partners should also undergo treatment. 2021 Wolters Kluwer Health, Inc  Ghonorrhea Neisseria gonorrhoeae , a Gram-negative, intracellular diplococcus. Patients at risk: patients particularly practicing receptive anal intercourse; women with pelvic inflammatory disease; and males and females with other sexually transmitted diseases. Symptoms: Diarrhea, mucopurulent discharge. Additional Arthritis, tenosynovitis, and skin rash. Pathophysiology: infection causes inflammation of the rectum characterized by mucosal erosions, erythema, and friability. Diagnostic tests: Rectal swab or biopsy testing with Gram stain and culture using Thayer–Martin medium. Treatment: The standard treatment is a single 250-mg dose of ce riaxone administered intramuscularly. Patients should also receive treatment for possible concomitant chlamydial infection with, for example, 100 mg doxycycline b.i.d. for 21 days.  Syphilis Treponema pallidum. Patients at Risk: patients practicing receptive anal intercourse and people with multiple sexual partners. Symptoms: anorectal discomfort, purulent anal discharge, di iculty with rectal evacuation, and tenesmus. Pathophysiology: the initial lesion is termed a “chancre” (primary syphilis), a well-demarcated ulcer that begins at the site of infection. This progresses to disseminated anorectal disease characterized by ulceration, fissuring, fistulas, proctitis, and lymphadenopathy. A reddish rash due to systemic infection (secondary syphilis) follows a er 2–10 weeks. Diagnostic testing: anorectal swab with dark field examination, serologic testing, and/or immunofluorescent staining. Treatment Benzathine penicillin 2.4 million units intramuscularly repeated a er 7 days. Tetracycline (500 mg q.i.d. for 15 days) or erythromycin (500 mg q.i.d. for 30 days) is given to patients who are allergic to penicillin.  HPV: venereal warts Organism Human papilloma DNA virus (HPV) from the papovavirus family. Patients at Risk: Sexual partners of infected individuals; sexually promiscuous people; patients with other sexually transmitted diseases such as gonorrhea, syphilis, and genital herpes; and victims of childhood sexual abuse. All sexually transmitted subtypes are associated with the development of anogenital warts. Symptoms; Fullness or a mass-like sensation in the perianal or genital region, exofitic lesions, pruritus ani, perianal or genital pain, rectal bleeding, and discharge. Proctoscopy or flexible sigmoidoscopy is required to determine the extent of anal and rectal involvement. Treatment: podophyllin (a cytotoxic agent) in tincture of benzoin is a commonly performed, o ice-based procedure. Benign anorectal disorders  Anal ssure A tear, crack, or ulceration of the anal canal. Can occur in any age group but is seen most commonly in young adults. Risk factors: cosntipation, in persons consuming low fiber, high fat diets. It is also a feature of Crohnʼs disease, anorectal infections, leukemia, tuberculosis, and HIV infection Pathophysiology: Most commonly seen in the posterior midline portion of the anal canal (this area may have decreased blood flow). Spasm of the internal anal sphincter may cause further reduction in blood flow to the posterior anal canal. The arrangement of the anal muscles leads to less well-developed support of the anoderm in this region. Symptoms: Pain and bleeding associated with defecation. The pain begins with defecation and persists a er completion of the bowel movement. Bleeding is generally limited. Anal ssure  Annal ssure Diagnosis: Most fissures are seen posteriorly Some patients may experience extreme physical discomfort on examination and may require anesthesia prior to full evaluation. Occasionally, anoscopy or flexible sigmoidoscopy is utilized Physical findings: 1. Sentinel pile (a small skin tag located outside of the anal canal near the fi ssure). 2. The fissure itself. 3. Hypertrophied anal papilla (originating at the dentate line) Treatment medical first line: (45–87% healing rate). Stool so eners, fiber supplements such as psyllium (6–12 g/day) or bran (10–15 g/day), local anesthetic agents (lidocaine, benzocaine, or pramoxine).  The pancreas: Histology Second line: (77–92% healing rate). Application of 0.2% topical nitroglycerin. Topical calcium channel blockers such as 0.2% nifedipine and 2% diltiazem. Third line: (43–100% healing rate). Botulinum toxin (Botox 5–100 IU) may be injected into the internal anal sphincter using a small gauge needle and syringe. Surgical options include internal anal sphincterotomy with or without fissurectomy.  Anal stenosis Narrowing of the anal canal. Epidemiology: Anal stenosis can be congenital, but this is rare. Most commonly, anal stenosis is an acquired. The most common cause of anal stenosis is prior hemorrhoidectomy. Benign causes: rior hemorrhoidectomy, fissurectomy, anal sphincter repair, rectovaginal fistula repair, electrocautery for anal condyloma, prior anorectal radiation therapy, rectal foreign body insertion, trauma, excessive laxative or mineral oil use, and Crohnʼs disease. Malignant causes Anal or rectal carcinoma. Pathophysiology: excess anal skin utilization to close the wound a er hemorrhoidectomy may cause stenosis. Carcinoma causes narrowing due to annular tumor growth. Scarring of the anus can occur secondary to Crohnʼs disease and as a complication of surgery. Laxative use and diarrhea due to anal sphincter hypertrophy. Normally, anal sphincter muscle function is preserved. 2021 Wolters Kluwer Health, Inc  Anal stenosis Symptoms: narrowing of the stool, passage of small stools, incomplete evacuation, painful defecation, and hematochezia Rectal examination: di iculty of passage of the finger into the rectum occurs because of decreased anal diameter. Additional tests may include anoscopy, flexible sigmoidoscopy, colonoscopy, barium enema, or pelvic imaging. Biopsies are obtained to rule out malignancy. Anorectal ultrasound may improve visualization of the anal canal to rule out malignancy. Examination under anesthesia may be required. Treatment: stool so eners, and periodic dilatation using a digital method or flexible dilators of increasing diameter. Surgical in cases of scarring, removal of the scar in combination with sphincterotomy. Anoplasty (the use of perianal skin to cover an area of the anal canal)  Anorectal abscess An infection that begins in the anal glands and extends into spaces around the anus and rectum. Epidemiology: most common in adults between the ages of 20 and 40 years. Twice as many males have this condition as females. Patients at risk: Crohnʼs disease, diabetes, heart disease, lymphoma, leukemia, anal and rectal cancer, radiation proctopathy, hidradenitis suppurativa, and infections of the perianal region. Infections including Chlamydia infection, actinomycosis, and tuberculosis. Pathophysiology: a collection of pus in the perianal or perirectal region initiated by obstruction of the anal glands followed by infections with the above-mentioned organisms or colonic bacteria. Infections may then expand into a variety of spaces within the anorectal region. Symptoms: pain and swelling, anal discharge and anorectal bleeding The World Society of Emergency Surgery (WSES) guidelines for the management of severe acute pancreatitis. 2019. Advances in acute pancreatitis. Co-critical Care Review. 2021 Wolters Kluwer Health, Inc  Anorectal abscess The four most important locations where pus may accumulate are the perianal, ischiorectal, intersphincteric, and supralevator spaces. Anorectal abscess  Anorectal abscess Examination reveals a swollen, tender, erythematous, and warm enlargement in the perianal region. Some drainage may be present and a pin-like opening may be revealed. Anesthesia may be required to complete the examination, including a digital rectal evaluation. Treatment: all anorectal abscesses require drainage. Excision of a fistula associated with the abscess may be required at a later stage. Culturing of the material collected a er drainage is suggested for individuals who are immunocompromised.  Hemorrhoids Dilation of anal venous structures. Occur in up to 50% of the adult population. Internal hemorrhoids: dilatations of the venous structures in the internal hemorrhoidal plexus. The veins are lined with rectal mucosa (transitional and columnar epithelium), which contains limited pain fibers. Originate from above the dentate line. External hemorrhoids: arise from the inferior venous plexus. They are lined with perianal squamous endothelium and contains a large number of pain fibers. Originate from below the dentate line. Patients at risk: secondary to chronic constipation, pregnancy, pelvic malignancy, chronic obstructive pulmonary disease with chronic cough, chronic diarrhea, and a variety of diseases or syndromes that increase the venous pressure within the pelvis. 2021 Wolters Kluwer Health, Inc External hemorrhoids/histology 2021 Wolters Kluwer Health, Inc External hemorrhoids/histology 2021 Wolters Kluwer Health, Inc Internal hemorrhoids/histology 2021 Wolters Kluwer Health, Inc  Hemorrhoids Pathophysiology: hemorrhoids are made up of blood vessels, connective tissue, and lining tissue (rectal or anal mucosa). Aging and straining reduce the ability of the connective tissue to provide adequate support for hemorrhoids resulting in their dilatation and decreased venous return. Internal hemorrhoids classification: First - degree prolapse: internal hemorrhoids move into the anal canal. Second - degree prolapse: prolapse of hemorrhoids outside the anal canal with straining, which resolves spontaneously. Third - degree prolapse: hemorrhoids protrude outside of the anal canal and require replacement by digital maneuvers. Fourth - degree prolapse : hemorrhoids protrude outside the anal canal and cannot be manually reduced. Complications: Internal hemorrhoids: bleeding External hemorrhoids: Thrombosis 2021 Wolters Kluwer Health, Inc  Hemorrhoids Symptoms Internal Hemorrhoids: Sensation of prolapse, mild discomfort, soiling, passage of small quantities of bright red blood. Severe pain associated with prolapse may suggest strangulation of prolapsed internal hemorrhoids. This is a serious, potentially life-threatening condition. External Hemorrhoids Pain (primarily with thrombosis). Presence of external skin tag and pruritus a Treatment: a high-fiber diet, increased fluids, and avoidance of straining. Topical local anesthetic creams (such as lidocaine, benzocaine, or pramoxine) should be applied 2–4 times/day. Rubber band ligation: this is an outpatient procedure performed a er placement of an anoscope. A specialized device grabs the hemorrhoid and places a rubber band tightly around it Other methods: cryosurgery, electrocoagulation, and saline injections. Surgical Internal hemorrhoids: most colorectal surgeons agree that third- and fourth-degree hemorrhoids require hemorrhoidectomy. 2021 Wolters Kluwer Health, Inc  Hemorrhoids External hemorrhoids: surgery is utilized in patients who have pain that is severe and/or lasts >48 h. Treatment involves either removal of the thrombosis or excision of the hemorrhoid. Thrombectomy alone cannot be performed a er approximately 48 h  Hydradenitis supurativa An acute or chronic inflammatory and infectious disorder of the apocrine (sweat) glands. It o en occurs in the perianal, inguinal, or genital areas. Epidemiology: most commonly occurs in younger individuals, between the ages of 16–45 years. It is more common in women. Patients at risk closely associated with Crohnʼs disease. It is more common in blacks than whites. Predisposing conditions include diabetes mellitus, seborrhea, and obesity. Pathophysiology the process is initiated when an apocrine duct becomes obstructed by keratinous secretions. This results in expansion of the sweat gland and secondary infection from skin flora and colonic bacteria. Poor skin hygiene may predispose to the development of the condition. Symptoms: pruritus, pain, and leakage from the a ected area. Diagnosis: lesions are erythematous and tender to palpation. A purulent discharge may be present. Extensive sinus formation with palpable abscesses and a honeycomb-like distribution of the lesions may be seen in the region of the anus, genitalia, gluteus, and thighs. 2021 Wolters Kluwer Health, Inc Hydradenitis supurativa: honeycomb pattern 2021 Wolters Kluwer Health, Inc  Hydradenitis supurativa Treatment: cleansing of a ected areas, antibiotic therapy with coverage for skin and colon flora may be e ective in early disease. Suitable antibiotics include tetracycline, erythromycin, Augmentin (amoxicillin/clavulanate potassium), and penicillin. Topical clindamycin has also been helpful, as have topical and intralesional injections with steroids. Surgical management for nonresponsive patients involves excision of the sinuses, sometimes with application of a gra to the surgical wound.  Perianal stula A pathologic connection between the anal canal and the perianal skin. Epidemiology: fistulas and abscesses are twice as common in men as in women. Most occur between the ages of 20 and 40 years. In 30% of patients it is associated with inflammatory bowel diseases. Patients at risk: prior radiation in the perianal region, prior anal surgery, hematologic malignancies, or prior anal trauma. Symptoms: drainage of pus, anal irritation, pain with defecation, pruritus ani, bleeding, and the sensation of a swelling or an opening near the anus. Diagnosis: a small external opening with or without drainage. According to Goodsallʼs rule, an imaginary transverse line should be drawn across the anus, and an external lesion seen anterior to this line opens directly from the anal canal. Perianal stula Perianal stula  Perianal stula The internal opening of the fi stula may be detectable using a proctoscope or flexible sigmoidoscope. MRI and anorectal ultrasound are helpful in identifying the full extent of fi stulous tracks. Treatment: for perianal fistulas is generally surgical. For low fistulas (internal opening below the puborectalis muscle), fistulotomy or opening of the fistula track (following the insertion of a probe into the external opening) is utilized. High fistulas (internal opening above the puborectalis muscle) o en require closure of the internal opening and performance of an advancement flap.  Perianal Chron´s disease The development of a variety of pathologic conditions of the perianal region such as fistulas, abscesses, and strictures caused by Crohnʼs disease. Epidemiology: perianal symptoms occur in more than 40% of patients. Perianal pathology includes the development of fistulas, anal fissures, and abscesses. Patients at risk: perianal involvement is more common in patients with rectal Crohnʼs disease (92%) and colonic Crohnʼs disease (52%) than in those with small intestinal Crohnʼs disease (14%). Symptoms: Pruritus ani and mild discomfort a er the passage of stool occur in some patients. When abscesses are present, pain, fever, and systemic symptoms may occur.  Perianal Chron´s disease Diagnosis Physical examination reveals enlarged anal skin tags (termed “elephant ears”), perianal openings due to fistulization, induration of the surrounding skin, anal abscesses, and anal strictures. Extension to the labia, scrotum, thigh, groin, and buttocks may be present. Testing may include the use of CT, magnetic resonance imaging, anorectal ultrasound, or fi stulography as clinically indicated. Treatment: including 6-mercaptopurine and azathioprine, may induce healing of perianal disease. Antibiotic therapy, particularly metronidazole. Surgical management includes incision and drainage of perianal and perirectal abscesses  Rectal prolapse Displacement of the rectal wall, the anal canal, and the outside of the anus. Epidemiology: it is up to 10-times more common in women than in men. It appears to be most common in multiparous women who are over the age of 50 years. Patients at risk: children with cystic fibrosis, spina bifida, congenital neurologic diseases, Marfanʼs syndrome, and other congenital mesenchymal diseases. Adults with schistosomiasis, spinal cord disorders, and prolapsing pelvic organs such as the uterus and bladder. Chronic constipation and straining and those with rectal or sigmoid tumors. Pathophysiology: chronic intussusception of the rectal mucosa appears to initiate the condition. A redundant sigmoid colon and decreased external anal sphincter function are aggravating factors. Long-standing rectal prolapse and straining on the toilet result in damage to pelvic nerves, which exacerbates the problem. Overall weakness of the pelvic floor appears to be another important factor. Symptoms: sensation of a mass protruding from the rectum upon defecation. Additional symptoms include rectal bleeding, fecal incontinence, pruritus ani.  Rectal prolapse In its most serious form, incarceration of the rectum within and outside of the anal canal may occur with associated ischemia, sepsis, and tissue gangrene. Diagnosis: examination with maneuvers to increase intraabdominal pressure (such as squatting and straining) will demonstrate a rectal prolapse. Presence of prolapsing mucosal folds di erentiates rectal prolapse from prolapsing internal hemorrhoids. All patients should have an endoscopic evaluation of the colon to rule out a rectal or sigmoid cancer, which may be present in up to 6% of a ected patients. D Treatment: a complete rectal prolapse is treated with surgery; milder forms may be managed with a high-fiber diet. Surgical Surgical approaches include anterior resection of the redundant rectum and sigmoid tissue.  Ulcerative proctitis A chronic infl ammatory bowel disorder only a ecting the rectum. Epidemiology approximately 40% of patients with ulcerative colitis only have manifestations of the disease in the rectum or rectosigmoid colon. Endoscopically, the disease is characterized by the presence of mucosal infl ammation beginning at the anal verge and extending without interruption in a proximal fashion. Microscopically, mucosal infl ammation is seen with edema and hemorrhage in the lamina propria. Mucosal infi ltration with a variety of infl ammatory cells Endoscopic view: ulceration, exudates, and loss of vascular pattern of mucosa, cryptitis and crypt abscess formation. Long-standing ulcerative colitis may result in the development of dysplasia and secondary carcinoma Symptoms: rectal urgency, incomplete evacuation, tenesmus, and, occasionally, fecal incontinence. Systemic symptoms including fever, weight loss, and signs and symptoms of anemia. Treatment: Mesalamine retention enemas are given as a single 4 g (60 mL) dose that is retained for 8 h at night and corticosteroids. 2021 Wolters Kluwer Health, Inc  Summary The World Society of Emergency Surgery (WSES) guidelines for the management of severe acute pancreatitis. 2019. Advances in acute pancreatitis. Co-critical Care Review. 2021 Wolters Kluwer Health, Inc Neoplasms of the annus  Anal adenocarcinoma The most common symptoms are anal pain, bleeding, sensation of a mass, and fistula drainage. Pathophysiology This is a rare tumor that arises from anal glandular tissue. It is o en seen developing in anorectal fistulas. Diagnosis Physical examination, anoscopy, and/or flexible sigmoidoscopy. Treatment is usually surgical, the most common procedure being abdominoperineal resection. Prognosis The recurrence rate a er surgery is very high (54%), and estimated mean survival is between 2 and 3 years.  Malignant melanoma A rare tumor that accounts for 0.5–1% of all anal cancers and 0.2–1.6% of all melanomas. Anal melanoma appears to be more than twice as common in women as in men.This tumor arises from melanocytes in the squamous mucosa of the anal canal and possibly the lower rectum. Risk factors: family history and an activating mutation of C-KIT. Symptoms: the most common symptoms are pain, a lump-like sensation in the anal region, constipation and evacuation di iculty, and change in bowel habits. Anorectal bleeding may also occur. Diagnostic testing: visualization of the external perianal region is o en su icient to identify the lesion. Lesions higher in the anal canal or in the lower rectum will be seen on fl exible sigmoidoscopy or anoscopy. Treatment: Surgical resection is required. Prognosis: very poor; 5-year survival has been estimated to be between 0 and 5%. Miscellaneous  Rectal foreign bodies Foreign bodies may be introduced either intentionally (sexual activity) or unintentionally (as a means of dislodging impacted stool). Patients at Risk; individuals practicing receptive anal sex utilizing foreign objects, rape victims, children, people with altered sensorium, and patients with rectal or anal strictures. Pathophysiology: a er placing large objects in the rectum, intense anal spasm and/or pain sometimes prevent simple removal. A sharp object may lodge itself in normal rectal mucosa. Other objects may become impacted at the rectosigmoid junction. Narrowed luminal caliber secondary to strictures or diverticular disease increases the likelihood of impaction. Symptoms: pain in the abdomen or rectum, rectal bleeding, discharge, and symptoms of peritonitis (abdominal distention, fever, peritoneal signs). Diagnostic testing_ physical examination should include careful abdominal examination to rule out peritonitis. The abdomen should be palpated for masses and the anus should be carefully inspected for evidence of fissure and/or anal trauma. Prior to the performance of a rectal examination, an abdominal X-ray should be performed. Subsequently, a digital rectal exam can be carefully performed (as long as a sharp object is not suspected). Assessment of anal sphincter tone is recommended. Patients may require anesthesia for adequate examination. Treatment Following adequate anesthesia, small objects may be digitally removed. Endoscopic removal may be possible in selected cases; removal of sharp objects requires an overtube. General anesthesia is used for the removal of larger objects. This can be performed using a variety of devices including obstetric forceps and modifi ed padded pliers. [email protected]