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 Table of Contents  
ORIGINAL ARTICLE
Year : 2014  |  Volume : 4  |  Issue : 1  |  Page : 25-30

Adult intussusception: An institutional experience and review of literature


Post Graduate Department of Surgery, L.L.R.M. Medical College, Meerut, Uttar Pradesh, India

Date of Web Publication14-Jul-2014

Correspondence Address:
Basant M Singhal
Post Graduate Department of Surgery, L.L.R.M. Medical College, Garh Road, Meerut - 250 004, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2278-9596.136706

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  Abstract 

Background: In adults, intussusceptions represent an uncommon form of intestinal obstruction, diagnosed in only 1-5% of cases. It can be idiopathic or secondary to a pathology in the bowel, which may be a malignancy in 9.75% of small bowel intussusceptions and 50-60% of large bowel intussusceptions. The aim of this study was to make a 15 year institutional review of adult intussusceptions.
Materials and Methods: Over a period of 15 years from January 1998 to December 2012, a total of 17 patients were diagnosed and managed as intussusceptions in our institution. A retrospective analysis of clinical, imaging and management data along with specimen and histopathological analysis was carried out.
Results: The age range was 21-58 years (mean 35 years) with a male preponderance (11 males: 6 females). Intussusceptions affected the small bowel in 12/17 (70.59%) and the large bowel in 5/17 (29.41%) of cases. The most common clinical presentation was insidious abdominal pain with sub-acute obstruction in 15/17 (88.24) of cases. Computed tomography scan was diagnostic in 88.23% cases. Intestinal tuberculosis (TB) was the most common etiology in 23.53% of the patients. Small bowel intussusceptions were not associated with malignancy, but all cases due to post-operative causes or TB affected small bowel only. Malignancy was responsible for intussusceptions only in the large bowel.
Conclusions: On analysis of our cases, we found that malignancy is responsible for intussusception only in the large bowel. Small bowel intussusceptions were not associated with malignancy, but all cases due to post-operative cause or TB affected small bowel only.

Keywords: Adult intussusception, intestinal obstruction, intestinal tuberculosis


How to cite this article:
Kaval S, Singhal BM, Kumar S, Singh CP. Adult intussusception: An institutional experience and review of literature. Arch Int Surg 2014;4:25-30

How to cite this URL:
Kaval S, Singhal BM, Kumar S, Singh CP. Adult intussusception: An institutional experience and review of literature. Arch Int Surg [serial online] 2014 [cited 2019 Sep 18];4:25-30. Available from: http://www.archintsurg.org/text.asp?2014/4/1/25/136706


  Introduction Top


Intussusceptions was first reported by Barbette of Amsterdam in 1674 and John Hunter in 1789, described clinico-pathological characteristics of this entity and named it as "intussusception." [1],[2] Adult intussusceptions is entirely a different clinical entity from the pediatric intussusceptions, especially regarding etiology and management. In adults, intussusceptions is uncommon as it is diagnosed in only 1-5% of cases of intestinal obstruction. [3],[4] Intussusceptions is defined as invagination or telescoping of a segment of the gastrointestinal tract (GIT) (intussusceptum) within the lumen of the adjacent segment (intussuscipiens). Once invagination starts, it leads to obstruction to the passage of intestinal contents as well as an obstruction to vascular flow. [5] The most common locations for intussusceptions are the junction between freely moving and fixed segments of the bowel, such as retroperitoneal segments or segments fixed by adhesions. [6] Adult intussusceptions are only 5% of all cases of intussusceptions and small intestine is the most common site. [4],[7] Intussusceptions can be classified according to anatomical location into entero-enteric, ileocecal, ileo-colic and colo-colic. [8],[9] In ileocecal intussusception, the ileocaecal valve acts as the lead point lesion. [10]

The exact cause of adult intussusception may not be known in 8-20% cases, which are designated as primary or idiopathic and more likely to occur in the small bowel. Other cases, are secondary to a pathology in the bowel wall acting as a lead point lesion or an irritant in the lumen which alters the normal peristalsis. [3],[8],[10],[11],[12] Various reports suggest adult intussusceptions is associated with a lead point lesion in >90% of cases. [8],[9],[10],[11],[12] In lead point lesion associated intussusception, the etiology can be benign or malignant. Approximately two-third of adult intussusceptions arise in the small bowel, of which idiopathic causes account for 20% of cases and lead point lesions are responsible for 80%. In the small bowel lead point lesions, approximately 65% are neoplastic (42.25% benign, 9.75% malignant). [10],[11] Various pathologies, which may serve as a lead point in the small bowel are inflammatory lesions, inflammatory bowel disease, Peutz-Jeghers syndrome, Meckel's diverticulum, strictures, adhesion and benign neoplasm (hemangioma, lipoma and leiomyoma). [6],[8],[10],[13] Malignancies associated with the small bowel intussusceptions are usually metastasis, most common being melanoma. [10] Rare primary malignancies such as adenocarcinoma, leiomyosarcoma, lymphoma and gastrointestinal stromal tumors have also been reported as causes of small bowel intussusceptions. [10],[11] In the adults transient intussusceptions has been reported in association with Coeliac disease and Crohn's disease. [5] In the large bowel intussusceptions, malignant lesions are responsible for 50-60% and benign lesions in 30% of cases while the rest 10% are idiopathic. Most common malignancies associated with the large bowel intussusception are adenocarcinoma and lymphoma, while benign lesions are lipoma, leiomyoma, adenomatous polyp, endometriosis, strictures, adhesions and tuberculosis (TB). [8],[10],[11]

A significant number of cases of adult intussusception have been reported in AIDS patients due to infective enteritis, lymphoid hyperplasia, Kaposi's sarcoma and non-Hodgkin's lymphoma (NHL). [14] Iatrogenic causes have also been reported, which include intestinal anastomosis, suture line, previous jejunostomy site, post-operative adhesions, sub mucosal bowel edema, intestinal dysmotility, electrolyte imbalance and long intestinal tubes. [15]

Relative rarity and insidious nature of this clinical condition, often presents a challenge to surgeons in making the diagnosis, as well as management. The objective of this study was to review adults with intussusceptions at our institution during last 15 years, with respect to clinical presentation, diagnosis and treatment.


  Materials and Methods Top


A retrospective study of a total of 939 adult patients (age >15 years) with intestinal obstruction admitted in the Surgery Department of our institution, over a period of 15 years from January 1998 to December 2012, was done. Among them, 17 patients (1.81%) were diagnosed and managed as intussusception. A comprehensive review of case records of these patients for age, sex, clinical presentation, results of diagnostic studies, per-operative findings and operative procedures was done. Specimen and histopathological analysis data were also evaluated to identify etiological factors.


  Results Top


Age range was 21-58 years (mean 35 ± 6 years). There were 11 males (64.70%) and 6 females (35.30%). Intussusceptions affected the small bowel in 12/17 (70.59%) and the large bowel in 5/17 (29.41%) cases.

A total of 15 patients presented with recurrent colicky abdominal pain for 2-6 months along with symptoms suggestive of sub-acute obstruction. Median duration of symptoms was 4 months. Only two patients presented with acute obstruction, both had recurrent pain for last 1 month, followed by absolute constipation with distension of the abdomen for 2 days. One patient had symptoms and signs of gangrene with hemodynamic instability [Table 1] and [Table 2].
Table 1: Clinical presentation (n = 17)

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Table 2: Symptoms and signs (n = 17)

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All patients had plain abdominal X-ray and abdominal ultrasonography (USG). These investigations were suggestive of intestinal obstruction in all patients. Plain X-ray of the abdomen was suggestive of abdominal mass in four patients while USG of abdomen identified abdominal masses and features of intussusceptions in these four patients as well as six more patients. Double contrast computed tomography (CT) scan was done in all patients for further evaluation and additional five patients were diagnosed as having intussusceptions. In three patients, CT scan identified lipoma, inflammatory fibroid polyp and leiomyoma as a lead point lesion for small bowel intussusceptions in one patient each. In four patients with colo-colic intussusceptions, a mass suggestive of malignancy was identified by CT scan, which was lymphoma in one patient and adenocarcinoma in three. In two patients, even CT scan could suggest only intestinal obstruction. In one patient, fiber-optic colonoscopy was done and adenocarcinoma of colon acting as a lead point lesion for colo-colic intussusception was identified. One patient was hemodynamically unstable with features suggestive of bowel gangrene and septicemia and hence he was not subjected to any invasive investigation.

In all the patients, laparotomy confirmed the diagnosis of intestinal obstruction due to intussusception. Details of anatomical type of intussusception, etiology and operative procedures done are given in [Table 3]. In patients presenting with acute obstruction one was ileocecal type due to TB, whereas the other leading to gangrene was the colo-colic type, due to human immunodeficiency virus (HIV) associated lymphoid hyperplasia. In two patients with jejuno-ileal and five ileo-ileal intussusceptions, operative reduction and resection was done, as malignancy was ruled out during laparotomy. In two cases of ileo-ileal intususception, there were features of intestinal TB like serosal granulomas and caseating mesenteric lymph nodes so primary reduction was done which revealed a 5-6 cm of grossly thickened distal ileum as a lead point. In two cases of ileocecal and ileo-colic intussusceptions there was a large bowel mass, therefore right hemicolectomy was done. The diagnosis of intestinal TB was confirmed on histopathological evaluation. In five cases of colo-colic intussusceptions, a right hemicolectomy was carried out in four patients because in three of them malignancy was suspected on CT scan and one had malignancy diagnosed on colonoscopy. One patient had associated gangrene involving the ascending and transverse colon so an extended right hemicolectomy was carried out.
Table 3: Details of type, etiology and operative procedures done

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In all the cases, bowel continuity was restored by primary anastomosis. The post-operative period was uneventful in all cases except for minor surgical wound infections in two patients. All patients were discharged between 8 th and 15 th post-operative day with the mean duration of hospital stay being 10.5 days.


  Discussion Top


Intestinal obstruction due to intussusceptions is rare in adults. It accounts for 0.003-02% of all hospital admissions and represents only 1-5% of cases of bowel obstruction. [3],[4] The most consistent symptom in adult intussusceptions is recurrent colicky abdominal pain of long duration, which may be associated with nausea, vomiting, abdominal distension, constipation and diarrhea. [6],[8],[10] An abdominal mass is palpable in only 7-42% of the patients. [16] Presentation of patients may vary from recurrent transient intussusceptions in 80% cases to acute intestinal obstruction in about 20% cases. [12],[17]

In this study, 15 (88.23%) patients presented with insidious symptoms and only 2 (11.76%) presented with acute obstruction. Ischemic complications are reported to be rare with intussusceptions. [13] In our study also, 1 (5.9%) patient with colo-colic intussusception, presented with gangrene and this patient was HIV positive.

Abdominal sonography in experienced hands, may allow diagnosis of intussusceptions with sensitivity and specificity close to CT scan. [10],[18],[19] However, the presence of air in distended loops or obesity may interfere with the accuracy of sonography. [10],[18] Classical sonography features of intussusception are "target sign" or "doughnut sign" on transverse view and "pseudo-kidney sign" or "Hayfork sign" on longitudinal view. [6] In this study, abdominal sonography revealed the diagnosis in ten cases (58.82%), which was also confirmed by CT scan. In five cases (29.41%), the diagnosis could be arrived at only by CT scan. In 15 (88.23%) cases, CT scan was able to diagnose intussusceptions. CT scan has sensitivity and specificity of 58-100% for the diagnosis of intussusceptions and it is considered as the imaging method of choice, due to its virtually pathogonomic features. [20],[21] An intussusceptions will appear as a "sausage shaped" mass in the longitudinal axis but will appear as a "target mass" in perpendicular axis. There is often an eccentric area of fat density within the mass representing intussuscepted fat and with visible mesenteric vessels within. A realm of contrast material is sometime seen encircling the intussusceptum. [6],[16],[20],[21] A CT scan may also define the location, nature of the mass and its relationship to the surrounding tissue. In addition, it may help in staging, if malignancy is suspected. [6]

Some authors consider fiber-optic endoscopy of lower GIT as invaluable in the diagnosis of intussusceptions presenting with sub-acute or chronic large bowel obstruction, having the additional advantage of identifying the lead point lesion. [10] In adults an underlying primary lesion as the lead point pathology is present in >90% of patients. [3],[5],[6],[8],[10],[12] In our study also 16 cases (94.12%), had a definite lead point pathology, while one case (5.88%) was idiopathic.

Approximately two-thirds of adult intussusceptions arise in the small bowel, of which idiopathic cases account for 20% cases and lead point lesions are responsible for 80%. [10],[11] Post-operative intussusceptions may be the cause in one-third cases of small bowel intussusceptions and these occur due to post-operative adhesions, anastomotic suture line, strictures or small bowel edema leading to disturbances in peristalsis. [3]

In this study, 12 cases (70.59%) were small bowel intussusceptions with benign lead point lesion in 11 cases (91.67%) while 1 (8.33%) case was idiopathic. In these benign lead point lesions, TB was responsible for 4 (33.33%) cases, benign neoplasms for 3 (25%) and post-operative adhesions for 2 (16.67%). One case was associated with Meckel's diverticulum, while another was due to anastomotic stricture developing 2 months after ileostomy closure. Large bowel intussusceptions were present in five cases (29.41%) of which 3 (60%) were due to adenocarcinoma of the ascending colon, one case (20%) due to NHL of caecum and one case (20%) due to HIV associated lymphoid hyperplasia of the proximal colon. On analysis of our cases, we found that malignancy is responsible for intussusceptions only in the large bowel. Small bowel intussusceptions was not associated with malignancy but all cases due to post-operative cause or TB affected small bowel only [Table 3].

The first successful surgery for intussusceptions was done by Hutchinson in 1871. [22] The principles of treatment of intussusceptions were described by sir Fredrik Trevens in the 19 th century, which are still being followed. [23] In pediatric intussusceptions conservative management is successful in >80% of cases, but for adults surgery is the treatment of choice. [3],[10],[11],[24],[25],[26] There has been some disagreement over, whether the reduction of intussuscepted bowel should be carried out before resection. The theoretical objections to this approach include intra luminal seeding or venous embolization of malignant cells, [27] possibility of perforation of the edematous bowel leading to peritoneal contamination, [8],[24],[26] possibility of spread of micro-organism though the veins of involved bowel, due to pressure of manipulation [8],[24],[26] and increased risk of anastomotic complications, due to manipulation of the edematous and friable bowel. [28] It has been widely reported that adult intussusceptions has organic lead point lesion in >90% of cases with risk of malignancy in 20-50% of them. [3],[27] Thus, most authors recommend en-bloc primary resection without reduction, whenever possible. [3],[10],[11],[24],[25],[26] If malignancy is suspected an adherence to oncologic principles is also recommended. However few recent reports favor, the initial reduction in the small bowel intussusceptions as the risk of malignancy is low. [9],[24] This approach can be followed with intent to limit the extent of resection if a benign etiology of the lead point lesion can be safely established by pre-operative investigations or there is a risk of leaving a short bowel. [25] There are reports which suggest that in experienced hands, laparoscopy can be employed as minimally invasive diagnostic procedure as well as for therapeutic resection. [29],[30]

Interestingly, in this study, there is a particular group of patients (4/17) in which the etiology of intussusceptions was intestinal TB. In these cases, specimen examination revealed that thickened terminal ileum has acted as a lead point with varying length of bowel involvement. Post resection, these cases responded favorably to anti tubercular drugs. According to global TB report 2012 of World Health Organization, the largest number of incident cases in 2011 were from India (2.0 million-2.5 million) and this accounted for 26% of global cases. [31] As it has been reported that abdominal TB is the most common site of extrapulmonary involvement with GIT being the site in 66-75% of them, the finding of intestinal TB is not surprising but intussusceptions is considered a rare complication. [32],[33],[34],[35],[36],[37] In our study, TB was a cause in 23.53% of all patients, representing the most common etiology, which has not been reported by other studies. [3],[6],[10],[12],[19],[28] This has an important implication, as with increasing incidence of HIV infection, incidence of abdominal TB is expected to rise in India. [33]


  Conclusion Top


Adult intussusception is a rare cause of intestinal obstruction. In a significant percentage of patients malignancy is the etiology, this diagnosis should thus be considered in patients having long standing abdominal pain. Although abdominal sonography may be useful, CT scan is the investigation of choice due to its high sensitivity and specificity, its ability to diagnose the intussusceptions as well as to differentiate between benign or malignant lesions. India has a considerable number of abdominal TB cases so it can be the etiology in a number of patients of intussusceptions. Surgery is recommended for management of adult intussusceptions and en-bloc resection of the bowel involved is the recommended surgical procedure.

 
  References Top

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    Tables

  [Table 1], [Table 2], [Table 3]


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