Which of the following is true regarding anorectal abscess and fistula?
Answer(s): E
The most common cause of anorectal fistula and abscess is infection of the anal glands, which empty into the anal canal at the level of the dentate line. Classification of anal fistula is based upon the relationship of the epithelialized tract to the anal sphincter muscle and can be intersphincteric (most common), transsphincteric, suprasphincteric, and extrasphincteric (least common). A symptomatic fistula is an indication for surgery because it rarely heals spontaneously. Despite popular teaching, there is little use for antibiotics in the primary treatment of anal abscess. As a rule, surgical drainage is required and antibiotics are only indicated if cellulitis is present. However, those patients who are immunocompromised, have valvular heart disease, or poorly controlled diabetes should always be considered for antibiotics.
The most common cause of surgery in a patient with Crohn's disease is which of the following?
Answer(s): D
Crohn's disease is a chronic inflammatory disease of the GI tract of unknown etiology. Both medical and surgical treatments are palliative in nature--there is no known "cure." pproximately 70% of patients with Crohn's disease will require an operation during their lifetime. The most common indication for surgery is recurrent bowel obstruction, followed by perforation with abscess and fistula formation.
A 26-year-old male presents with abdominal pain and bloody diarrhea. On examination, he has a low- grade fever and mildly tender abdomen. Lower endoscopy is performed which reveals edematous mucosa with contiguous involvement from the rectum to the left colon. Random biopsies are performed which reveals acute and chronic inflammation of the mucosa and submucosa with multiple crypt abscesses.There are no granulomas seen.What can you tell this patient about his condition?
Ulcerative colitis is a diffuse inflammatory disease of the colon and rectum with unknown etiology. Unlike Crohn's disease, surgical removal of the entire colon and rectum provides a complete cure. Nonetheless, many patients are treated successfully with medical therapy including corticosteroids and can avoid the potential complications of surgery and lifelong ileostomy. Ulcerative colitis usually presents as bloody diarrhea, fever, and abdominal pain. The disease process begins in the rectum, advances proximally in a contiguous fashion, and affects the superficial layers of the colon wall. Crohn's disease is located anywhere from the mouth to anus, has skip lesions, and is transmural in nature. Histologically, superficial inflammation with crypt abscesses is most indicative of ulcerative colitis, whereas deeper involvement with granulomas and fissures are most characteristic of Crohn's disease. Both diseases may present with extraintestinal manifestations such as arthritis, skin lesions, and hepatic dysfunction, but perianal disease with fistula formation is characteristic of Crohn's disease. Patients with ulcerative colitis have a 1020% risk of developing colon cancer within 20 years after diagnosis. The incidence is also increased in those with Crohn's disease but to a lesser extent. Surveillance colonoscopy is essential in patients with long-standing disease
A 46-year-old female presents to your office with rectal bleeding, itching, and irritation. On examination, a 3-cm ulcerating lesion is seen in the anal canal. Biopsy of the lesion reveals squamous cell carcinoma (SCC). Which of the following is the most appropriate treatment?
Answer(s): A
Anal carcinoma can arise from several epithelial cell types in the anal canal including squamous, basaloid, cloacogenic, and mucoepidermoid. For early, superficial lesions less than 2 cm, an attempt can be made to excise the lesion completely with negative margins. Otherwise, the standard of care is a multimodality chemoradiation protocol, which classically includes itomycin C and 5-FU in combination with external beam radiation therapy to the tumor and the pelvic and inguinal lymph nodes. The long-term survival rate after chemoradiation alone compares favorably with radical surgery. Abdominal perineal resection is reserved for persistent or recurrent disease. Low anterior resection refers to resection of the upper and middle rectum and plays no role in the treatment of anal cancer. Inguinal lymph node dissection is not indicated. Any clinically suspicious node should be biopsied, and if positive, treated with radiation. Thus, even a small anal cancer with a positive lymph node should be treated with chemotherapy instead of surgery.
During initial exploration in a patient scheduled to undergo a right hemicolectomy for colon cancer, a deep 4-cm liver mass is seen in the right lobe of the liver. The left lobe appears to be normal. Intraoperative biopsy of the lesion is positive for metastatic colon cancer. The best management of this patient includes which of the following?
Answer(s): B
Colon cancer is the most common metastatic lesion of the GI tract to the liver. Approximately 50% of patients with colorectal cancer will have liver involvement. Generally, synchronous liver metastasis should not be resected during the initial operation for the primary tumor. Only a solitary, small, peripherally located lesion in a hemodynamically stable patient would be an acceptable indication for a wedge resection. Otherwise, the planned colon resection should be completed. A second procedure can be planned after a thorough metastatic evaluation is completed using various diagnostic modalities such as intraoperative ultrasound, CT, MRI, and/or PET scan. A delay of weeks to months between surgeries has not been shown to have a negative impact on long-term survival. The delay may help select patients who may benefit the most and exclude those who develop widespread metastatic disease during the interval. Chemotherapy only is inappropriate because, even in the presence of metastatic disease, the primary colon carcinoma should be resected to prevent later complications such as bleeding, perforation, or obstruction. The 5-year survival rate following resection of isolated hepatic metastasis from colorectal cancer now exceeds 50%.
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