Journal of Clinical Outcomes Management. 2014 October;22(10)
References
Laboratory Evaluation and Endoscopy
Laboratory testing reveals normal hemoglobin, white blood cell count, mean corpuscular volume, and electrolytes. Endoscopy is performed and reveals an irregular solitary ulcer base covered in fibrinous exudates in the rectum ( Figure 2 ).
What is SRUS and how is it diagnosed?
Evaluation and Diagnosis
SRUS is characterized by single or multiple ulcerations of the rectal mucosa along with distinct pathologic changes [17]. The term solitary rectal ulcer is a misnomer because many patients have more than 1 lesion, and it is not always an ulcer. Patients with SRUS present with several symptoms, but the most common is passage of blood or mucus, and up to 26% may be asymptomatic [18]. The pathophysiology of this condition is poorly understood. Multiple mechanisms have been implicated, including occult or overt rectal prolapse, dyssynergia, rectal mucosal intussusception, rectal hypersensitivity with a persistent feeling of a need to defecate, and reduced mucosal blood flow [19].
The diagnosis of SRUS is based on the patient’s clinical history combined with endoscopy and histopathology findings. Endoscopically, the lesions may vary in appearance. Shallow ulcerations on hyperemic surrounding mucosa located on the anterior wall is the most common finding [17]. Lesions vary in size, although most are 1 to 1.5 cm in diameter [17] and rarely involve more than half the circumference of the rectal wall. Polypoid lesions occur in approximately 25% of patients with SRUS, and multiple lesions occur in 30% [17].
Obtaining specimens for histology is an important step in the evaluation of SRUS. The differential diagnosis includes Crohn’s disease, ulcerative colitis, ischemic colitis, and malignancy. The typical histologic findings include fibromuscular hyperplasia with smooth muscle infiltration of the lamina propria, thickening of the muscularis mucosa, regenerative changes, and distortion of the crypt architecture [17].
Are physiologic or imaging studies helpful in the diagnosis of SRUS?
Two complementary physiologic tests for SRUS are anorectal manometry and defecography. Anorectal manometry often shows evidence of dyssynergia and rectal hypersensitivity in patients with SRUS [20,21]. Hyper-sensitivity may produce a sensation of incomplete evacuation, which in turn results in excessive straining. Defecography may reveal rectal mucosal intussusception or overt rectal prolapse. The patient in this case had evidence of rectal hypersensitivity on anorectal manometry along with excessive perineal descent on defecography.
What are treatment options for SRUS?
Treatment of SRUS is not standardized. The options include topical medical therapy, biofeedback, and surgery. Uncontrolled studies have suggested that 5-aminosalicylic acid enema [22], sucralfate enema [23], steroid enema [24], and fibrin glue [25] may improve symptoms. Patients who fail topical therapy and have evidence of dyssynergia on anorectal manometry should receive biofeedback therapy. A case-control study of biofeedback involving 11 patients with refractory SRUS and 15 healthy controls showed improvement in anorectal function, including dyssynergia [21]. At follow-up endoscopy, 36% had complete mucosal healing and more than 50% showed partial healing. In a study involving 16 patients with SRUS and 26 healthy controls, Jarrett et al [26] showed that 75% of patients who underwent biofeedback therapy had improved and 31% had ulcer resolution. Surgical therapy should be considered in rare patients who are refractory to medical therapy. The Delorme procedure is commonly performed with a success rate of 42% to 100% [27].