Transanal evisceration of small bowel in two patients with chronic rectal prolapse: case presentation and literature review

Abstract

There are fewer than 100 documented cases of transanal small bowel evisceration in the literature. We report two cases of this rare surgical emergency in an 84-year old man and a 79-year old woman. Both patients required urgent laparotomy, resection of ischaemic bowel and transabdominal resection of the rectal defect with colostomy. Postoperative recovery was uneventful. Rare imaging and clinical photography are shared to highlight the extreme nature of this condition. We identified 38 relevant cases of reported bowel evisceration through our literature review. Most patients were elderly women with untreated rectal prolapse. Gynaecological comorbidity was another risk factor. The aetiological mechanism is suspected to stem from chronic ischaemic insult to the rectal wall, resulting in thinning and subsequent perforation. Surgical management may consist of primary suture repair of the rectal tear, or a Hartmann’s procedure. Timely intervention is essential to minimise patient morbidity and mortality.

Background

Rectal rupture and subsequent transanal small bowel evisceration is a rare but serious presentation that has been documented several times since its first description in 1827.¹ Common risk factors include advanced age, female sex and a history of chronic rectal prolapse. We explore several hypothesised mechanisms and predisposing factors underlying the long-term pathogenesis of this condition. The acute presentation, however, is dramatic and requires timely surgical intervention to reduce serious morbidity and mortality.

Case history

Patient A

An 84-year-old man presented with central abdominal pain and prolapsing small bowel from his anus. This was preceded by faecal incontinence and rectal bleeding. He had a long history of rectal prolapse and had most recently undergone two Altemeier’s procedures in the past two years, preceded by a Delorme’s approach seven years ago. His past medical history included hypertension, ischaemic heart disease, Parkinson’s disease, prostate cancer and non-Hodgkin’s lymphoma; the two cancers were in remission.

On examination, he had approximately two metres of oedematous, dusky small bowel protruding through the anus (Fig 1). He was haemodynamically stable, and his blood tests revealed a normal white cell count, C-reactive protein and renal function. His lactate was 1.8mmol/l.

Figure 1.

Clinical photograph of patient A showing small bowel loops protruding through the anus

The patient was managed with intravenous broad-spectrum antibiotics, fluid resuscitation and analgesia, then was taken to theatre. National Emergency Laparotomy Audit (NELA) adjusted mortality was calculated as 27.4% and adjusted morbidity was 51%.

Intraoperatively, there was a perforation in the anterior rectal wall with no evidence of peritoneal soiling. The entire prolapsed small bowel was non-viable but had not perforated. The small bowel was resected and anastomosed. The large rectal defect was resected transabdominally with the distal end stapled, and an end-colostomy was performed.

A period of ionotropic support was necessary in the high-dependency unit. The patient was discharged 10 days postoperatively. At four-month follow-up, he remained well. Histological analysis of the perforated rectum showed inflammatory changes.

Patient B

The second patient was a 79-year-old woman with lower abdominal pain and transanal prolapse of the small bowel after defecation. The patient experienced large amounts of blood per rectum and faeculent vomiting. She had known chronic rectal prolapse when defecating, self-managed with digital manual reduction. Her past medical history included urinary incontinence, hysterectomy, hypertension, transient ischaemic attacks, osteoarthritis, sleep apnoea and anxiety disorder. Six years ago, she reported altered bowel habits and underwent a computed tomography of abdomen and pelvis (CTAP) with intravenous contrast scan and a colonoscopy, all of which were normal. During her emergency surgical clerking it transpired that she had not previously sought medical advice for her chronic rectal prolapse.

Examination showed ischaemic prolapsed small bowel. She had an elevated white blood cell count and normal renal function. Blood gases showed pH 7.29 and lactate 3.2mmol/l. CTAP with intravenous contrast showed a large enterocoele in the rectovaginal space and free air outside the bowel lumen, suggesting intestinal perforation (Fig 2).

Figure 2.

Sagittal (top) and axial (bottom) views of preoperative computed tomography of patient B showing small bowel evisceration transanally

NELA adjusted mortality was calculated as 23% and adjusted morbidity was 96%. The patient was given broad-spectrum antibiotics, fluid resuscitation and analgesia, before undergoing emergency surgery.

Intraoperatively, there was a perforation in the anterior rectal wall, above the peritoneal reflection with one metre of herniated non-viable small bowel. The small bowel and adjacent ascending colon were resected and an ileocolic side-to-side stapled anastomosis was performed. The rectal perforation required transabdominal partial proctectomy with an end-colostomy and stapling of the rectal stump.

Three weeks postoperatively, the patient developed hospital-acquired pneumonia. This resolved with intravenous antibiotics and she was discharged following a prolonged postoperative rehabilitation course of eight weeks. She was clinically well at the three-month follow-up.

Discussion

Rupture of the rectum and evisceration of small bowel through the perforation site is a rare emergency presentation, with fewer than 100 documented cases in the literature. We conducted a literature review of reports of this condition over the past 20 years using the MEDLINE database and identified 36 such cases. Together with our two reported patients, a total of 38 similar cases have been reported over this period. Numerous cases of transanal bowel evisceration with a clear traumatic origin have been reported in the younger population, but these were excluded from the review.² Cases of rectal rupture without small bowel evisceration were also excluded.

Both our patients were elderly and had a long history of rectal prolapse. This is consistent with past literature reviews by Morris et al and Hovey and Metcalf.^3,4 In our review, 66% (n = 25) of patients presenting with transanal evisceration of small bowel had known rectal prolapse. Only four patients had undergone a variety of prior surgical repair for their rectal prolapse; surgery included perineal and abdominal approaches (Table 1). The overall patient demographic was overwhelmingly elderly (median age 81 years) and female (82%).

Table 1.

Characteristics and outcomes in reviewed cases

	Study	Year	Sex	Age (years)	History of prolapse/constipation	Precipitating factor	Procedure	Small bowel resection	Outcome	Last follow–up (months)
1.	Jeong et al15	2000	F	81	Prolapse	None	Sutured tear & colostomy	Yes	Survived	–
2.	Al-Akbari et al10	2000	M	22	None	Defaecation	Sutured tear & colostomy	No	Survived	36
3.	Nari et al16	2001	F	72	Prolapse & surgery (Mesh rectopexy)	None	Sutured tear & colostomy	Yes	Survived	–
4.	Suzuki et al17	2003	F	86	Prolapse	None	Sutured tear	Yes	Died	–
5.	Mori et al18	2003	F	88	None	Defaecation	Sutured tear	No	Survived	–
6.	Morris et al19	2003	F	86	Constipation	Defaecation	Hartmann’s	Yes	Died	–
7.	Papapolychroniadis et al3	2004	F	83	None	None	Sutured tear	Yes	Died	–
8.	Ghosal et al20	2004	F	72	Constipation	Defaecation	Sutured tear	No	Survived	1.5
9.	Anthony et al21	2005	F	82	Constipation	Defaecation	Laparoscopic suturing	No	Survived	6
10.	Shoab et al11	2007	F	90	Prolapse	Defaecation	Thiersch repair + suturing	No	Survived	–
11.	Keshava et al14	2007	F	88	Prolapse	None	Hartmann’s	Yes	Survived	–
12.	Kiyak et al22	2008	F	67	Prolapse	Defaecation	Sutured tear & colostomy	No	Survived	–
13.	Furuya et al23	2008	F	68	Prolapse	Defaecation	Hartmann’s	No	Survived	1.5
14.	Mizuno et al24	2010	F	87	Prolapse & Constipation	Digital manipulation	Sutured tear	Yes	Survived	2
15.	Takahashi et al25	2010	F	69	Prolapse	Defaecation	Sutured tear	No	Survived	–
16.	Bhat et al26	2010	M	14	Constipation	Defaecation	Sutured tear	Yes	Survived	–
17.	Trinidade et al27	2010	F	66	Prolapse	Reduction of Prolapse	Sutured tear	No	Survived	–
18.	Hanaoka et al28	2012	F	81	Prolapse	Defaecation	Hartmann’s	No	Survived	1
19.	Frolov et al29	2012	M	69	Constipation	Defaecation	Sutured tear & colostomy	No	Survived	6
20.	Walton et al30	2013	F	94	Constipation	None	Anterior resection + colostomy	Yes	Survived	–
21.	Berwin et al9	2012	F	84	Prolapse	Defaecation	None	No	Died	–
22.	Kumar et al31	2013	M	60	Prolapse	Defaecation	Anterior resection + colostomy	No	Survived	3
23.	Chetty et al32	2014	F	68	Prolapse	Digital manipulation	Sutured tear & colostomy	No	Died	–
24.	Martínez Pérez et al33	2014	F	81	Constipation	Digital manipulation	Hartmann’s	No	Survived	2
25.	Kornaropoulos et al34	2015	F	78	Prolapse	Defaecation	Hartmann’s	Yes	Survived	2
26.	Salvador Rosés et al35	2016	M	34	Constipation	Defaecation	Hartmann’s	No	Survived	–
27.	Ahmad et al36	2016	M	55	Prolapse	Defaecation	Hartmann’s	No	Survived	6
28.	Sanou et al37	2016	F	80	Prolapse & Constipation	Defaecation	Sutured tear	Yes	Survived	3
29.	Hertig et al38	2016	F	44	Prolapse & Constipation	Defaecation	Laparoscopic suturing of tear & colostomy	No	Survived	6
30.	Teklote et al12	2016	F	79	Prolapse & surgery (Altemeier)	-	Hartmann’s	No	Survived	–
31.	Kuwabara et al39	2016	F	75	Prolapse	Defaecation	Sutured tear & colostomy	Yes	Survived	–
32.	Pisano et al40	2017	F	74	Constipation	None	Hartmann’s	Yes	Survived	–
33.	Prassas et al41	2017	F	91	Constipation	Defaecation	Hartmann’s	Yes	Survived	–
34.	Sazhin et al7	2017	F	87	Prolapse & Constipation	None	Hartmann’s	Yes	Survived	2
35.	Shomi et al42	2017	F	93	Prolapse & surgery (laparoscopic rectopexy)	Defaecation	Sutured tear & colostomy	Yes	Survived but recurred	7
36.	Akbulut et al13	2019	F	75	Prolapse	None	Anterior resection + colostomy	No	Survived	–
37.	Patient A	2019	M	84	Prolapse & surgery (Altemeier, Delorme)	None	Hartmann’s	Yes	Survived	4
38.	Patient B	2019	F	79	Prolapse	Defaecation	Hartmann’s	Yes	Survived	3

The significance of rectal prolapse in the pathogenesis of rectal perforation was initially described by Wrobleski and Dailey.⁵ They hypothesised that rectal prolapse causes thinning of the rectal wall over time, and combined with a sudden increase in intraabdominal pressure, risks rectal rupture causing evisceration of abdominal contents. This may explain the strong association between rectal prolapse and a history consistent with raised intra-abdominal pressure; in our review, 63% of patients reported a sudden event with raised intra-abdominal pressure prior to the acute presentation.

A rectal prolapse may develop via an initial rectorectal, then rectoanal, intussusception. Subsequent rectal wall thinning occurs secondary to higher intraluminal tissue pressure, causing ischaemic damage of the mucosal lining, which may progress to solitary rectal ulcer syndrome at the anterior wall of the rectum.⁶ The anterior location is compatible with the site of perforation in all reviewed cases. Additionally, a report from Germany showed a sequential link between an ischaemic lesion in the rectal wall and subsequent perforation and bowel evisceration three months later.⁷ In 46% of patients since 2000, histology showed chronic ischaemic or inflammatory changes around the perforation site (Table 2).

Table 2.

Summary of patient characteristics

Characteristic	Patients
	(n)	(%)
Female sex	31	82
History of rectal prolapse	25	66
History of neuropsychiatric Illness	7	19
Gynaecological historya	10	33b
Precipitated by defaecation	24	63
Perforation site above peritoneal reflection	21	70
Resection	18	47
Hartmann’s procedure	14	37
Mortality	5	13
Ischaemic/inflammatory changes on histology	11	46

^aUterine prolapse, hysterectomy, caesarean section, urinary incontinence.

^bFemale patients.

While chronic rectal prolapse thins the rectal wall from the luminal surface, it has been proposed that the rectal wall can be thinned out by extraluminal pressures. Enterocoeles exert a compressive force on the anterior rectal wall, especially during times of increased intra-abdominal pressure such as defaecation.⁸ This can be exacerbated in patients with past hysterectomies, leading to a deeper pouch of Douglas and a greater area of contact between the small bowel and anterior rectal wall.⁹ Particularly, patient B demonstrated a large enterocoele in the rectovaginal space close to the tear (Fig 2). Similarly, Jeong et al postulated that chronic uterine prolapse predisposes to rectal prolapse by causing traction on the rectal wall.¹⁰

Patient A had three previous transanal procedures to repair his chronic rectal prolapse. It is difficult not to assume that these may have contributed to weakness of the rectal wall. Operatively, these procedures did not alter the anatomy of the pelvis, nor did they create a deep rectovesical pouch. His age, frailty, chronic constipation, patulous anus and weak anal sphincters were likely predisposing factors underlying his recurrent rectal prolapse.

There were 13 cases of rectal rupture without previous prolapse. Although termed ‘spontaneous’, the histories of these patients often include chronic constipation and may indeed have had undocumented rectal prolapse. These patients may have large enterocoeles or suffered from rectal intussusception as described above, in the absence of a complete external prolapse. Both pathologies would make the rectal wall susceptible to perforation at times of increased abdominal pressure.

The operative approaches in all previous cases involved reduction of the small bowel and resection of ischaemic bowel (47% of cases; Table 2). In uncomplicated cases without peritoneal soiling or extensive bleeding, the rectal perforation was sutured in two layers, with or without a covering colostomy. Some authors have successfully performed laparoscopic suturing of the rectal defect.^11,12 Given the aetiology, simple suturing of the tear may predispose recurrence, as reported in one of the reviewed cases.¹³ However, estimation of the overall recurrence risk is limited by the absence of long-term follow-up data and small patient numbers. Shoab et al has complemented primary suturing of the perforation with Thiersch repair of the rectal prolapse, to address the underlying cause of perforation.¹⁴

Conclusion

Transanal evisceration of small bowel is a rare presentation, often occurring in elderly female patients with a chronic history of constipation and/or rectal prolapse. Management must focus on timely resuscitation and surgery to minimise the risk of small bowel ischaemia. Operative approaches depend on the viability of prolapsed bowel as well as the patient’s physiological reserve.