Gattuso J M, Kamm M A
St Mark's Hospital, London.
Gut. 1997 Jul;41(1):93-9. doi: 10.1136/gut.41.1.93.
Dilatation of the rectum and/or colon, in the absence of demonstrable organic disease, is an uncommon and poorly characterised condition.
To characterise the clinical and diagnostic features, and response to treatment, of patients with idiopathic megarectum (IMR) and idiopathic megacolon (IMC).
A retrospective review was undertaken of all patients operated on for these conditions over a 23 year period. In addition all patients treated over a three year period were prospectively studied by means of a questionnaire, contrast studies of the upper and lower intestine, spine x rays to exclude spinal dysraphism, anorectal physiological studies, and assessment of clinical outcome. Patients with Hirschsprung's disease and other known causes of gut dilatation were excluded.
(i) Retrospective study: Of 63 operated patients, 22 had IMR, 23 had IMR and IMC, and 18 had IMC only. Five patients with IMC had previous sigmoid volvulus, and three had associated non-gastrointestinal congenital abnormalities. Faecal incontinence was always associated with rectal impaction and 14 patients (82%) with IMR alone had had manual disimpaction. (ii) Prospective study: Twenty two patients had IMR, with a median rectal diameter of 10 cm (normal < 6.5 cm). Six patients had IMC and one patient had IMR and IMC. Patients with IMR were significantly (p = 0.0007) younger than patients with IMC. All patients with IMR became symptomatic in childhood, compared with half the patients with IMC who developed symptoms as adults. Patients with IMR all presented with soiling and impaction, compared with patients with IMC whose symptoms were variable and included constipation or increased bowel frequency, pain, and variable need for laxatives. No upper gut dilatation was seen in either group of patients. Spinal dysraphism was seen in two of 18 patients with IMR and two of four with IMC, suggesting extrinsic denervation as a possible cause in a minority. Twelve of 22 patients with IMR had a maximum anal resting pressure below normal, indicating sphincter damage or inhibition. Both IMR and IMC patients had altered rectal sensitivity to distension, suggesting that despite lack of dilatation the rectum in IMC has altered viscoelasticity, tone, or sensory function. Fifteen of 22 patients with IMR were successfully managed with laxatives or enemas, but seven required surgery. Two of seven patients with IMC required surgery, including one for sigmoid volvulus.
Patients with IMR differ clinically, diagnostically, and in their outcome from patients with IMC. These conditions demand specific investigation, and intensive treatment, to achieve optimum care.
在无明显器质性疾病的情况下，直肠和/或结肠扩张是一种罕见且特征不明的病症。
描述特发性巨直肠（IMR）和特发性巨结肠（IMC）患者的临床及诊断特征，以及对治疗的反应。
对23年间因这些病症接受手术的所有患者进行回顾性研究。此外，对三年期间接受治疗的所有患者进行前瞻性研究，方法包括问卷调查、上下消化道造影、排除脊髓发育异常的脊柱X光检查、肛肠生理学研究以及临床结局评估。排除患有先天性巨结肠病和其他已知肠道扩张病因的患者。
（i）回顾性研究：63例接受手术的患者中，22例患有IMR，23例患有IMR和IMC，18例仅患有IMC。5例IMC患者曾有乙状结肠扭转，3例伴有非胃肠道先天性异常。大便失禁总是与直肠粪嵌塞相关，14例（82%）仅患有IMR的患者曾接受过人工排便。（ii）前瞻性研究：22例患者患有IMR，直肠中位直径为10 cm（正常<6.5 cm）。6例患者患有IMC，1例患者患有IMR和IMC。IMR患者比IMC患者明显年轻（p = 0.0007）。所有IMR患者在儿童期出现症状，而IMC患者中有一半在成年期出现症状。IMR患者均表现为便污和粪嵌塞，而IMC患者的症状则各不相同，包括便秘或排便次数增加、疼痛以及对泻药的不同需求。两组患者均未发现上消化道扩张。18例IMR患者中有2例、4例IMC患者中有2例出现脊髓发育异常，提示少数患者可能存在外在性去神经支配。22例IMR患者中有12例最大肛门静息压低于正常，表明括约肌受损或受抑制。IMR和IMC患者的直肠对扩张的敏感性均发生改变，这表明尽管IMC没有扩张，但直肠的粘弹性、张力或感觉功能已发生改变。22例IMR患者中有15例通过泻药或灌肠成功治疗，但7例需要手术。7例IMC患者中有2例需要手术，其中1例因乙状结肠扭转手术。
IMR患者在临床、诊断及预后方面与IMC患者不同。这些病症需要进行特定检查和强化治疗，以实现最佳护理。
