Meckel diverticulum: ten-year experience in adults.

Objectives: Meckel diverticulum, a congenital gastrointestinal anomaly, is well studied in pediatrics, but less so in the adult population. At the Charleston Area Medical Center (CAMC), in addition to the removal of Meckel diverticula in symptomatic patients, diverticula are commonly removed when found incidentally during other procedures. We present our experience over the past ten years with this condition, unusual in the adult population.

Methods: From 1992 to 2002 at the Charleston Area Medical Center, Meckel diverticula were removed from 47 patients older than 18 years of age. We reviewed the age, sex, indication for removal, pathologic findings, and perioperative complications of these cases.

Results: Diverticula were removed most often from female patients (31 female, 66%; 16 male, 34%). The removal of the diverticulum was incidental in 35 patients (74.5%) and symptomatic in 12 (25.5% percent). Symptomatic patients presented with: obstruction (n = 4), acute bleeding (n = 1) and diverticulitis (n = 7). Female patients were significantly less likely than male patients to be symptomatic (4 of 31, 13% among females, and 8 of 16,50% among males; P < 0.05). Heterotopic mucosa was identified in six patients, two of whom were symptomatic at the time of removal. Gastric mucosa was found in all six of the diverticula with ectopic mucosa, although one of the six had a mixed gastric and pancreatic cell population. One asymptomatic patient had a malignancy identified as a 1.5 cm carcinoid with no evidence of metastatic disease. An adenomyoma was found incidentally in one patient upon pathologic evaluation. Hospital complications that could possibly be attributed to removal of diverticula included two wound infections and two anastomotic leaks requiring exploration (8.5% morbidity). Complications were experienced by two asymptomatic females, one asymptomatic male, and a symptomatic male. There were no mortalities.

Conclusions: Meckel diverticulum is found infrequently in the adult population. Adults rarely become symptomatic, but symptoms that do arise are associated with significant morbidity. Complications directly attributable to diverticulum removal are uncommon; however, those that do occur are often life threatening. Therefore, incidental removal of asymptomatic diverticula, particularly in women, is not recommended.

Key Words: adult, Meckel diverticulum, surgery

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Discussion of Meckel diverticulum begins early in the career of physicians. A topic frequently addressed in pediatrics, it is not as clearly understood in the adult population. Following the "rule of twos" found in every review book for medical students (ie, found in 2% of the population, twice as common in males, most frequently found in those less than 2 years of age, and most commonly 2 feet from the ileocecal valve), surgical residents begin searching for this congenital anomaly with their first surgical exploration. However, as complications associated with Meckel diverticula tend to decrease with increasing age, a true diverticulum is rarely discovered in the adult. (1) Over the past 10 years, we have taken special note of adult Meckel diverticulum patients at the Charleston Area Medical Center (CAMC). In the literature, examinations of this condition dedicated to the adult population are sparse. We review our experience with surgical removal of the diverticulum.

Materials and Methods

After receiving institutional review board authorization, a retrospective review was completed of all cases treated with surgical removal of Meckel diverticula at CAMC, a tertiary care teaching facility serving southern West Virginia and parts of the bordering states of Ohio and Virginia. From 1992 to 2002, 47 patients underwent surgical removal of Meckel diverticula. Data were extracted via retrospective chart review, primarily from operative and pathology reports. Data collected for each patient included gender, age at removal, indication for removal, method of removal, pathologic findings, and perioperative complications.

Statistical tests used to analyze the data included t tests and the Fisher exact test. Age was collected as a continuous variable, and then categorized into seven levels for analysis (ie, 19-29 yr, 30-39 yr, etc). For all reported analyses, a two-tailed significance of P < 0.05 was used. All analyses were performed using SAS for Windows, Version 8.1 (SAS Institute, Inc., Cary, NC).

Results

Forty-seven adult patients underwent surgical removal of a Meckel diverticulum between 1992 and 2002. (Table 1) Significantly more females had diverticula removed than males (31 of 47; 66%; P < 0.05). The average patient age was 54.7 years, with no significant age difference between males and females. Diverticula were removed incidentally at the time of exploration in 35 patients (74.5%). Twelve patients were symptomatic (33% female; symptomatic M:F ratio = 2:1). Of these, four presented with obstruction, eight with diverticulitis, and one with an acute hemorrhage requiring six units of packed red blood cells in a 24-hour period (one patient had both obstruction and diverticulitis). Eight (66.7%) of the 12 symptomatic patients presented with abdominal pain and pathologic inflammatory changes. The difference in the number of males versus females that were symptomatic (Figure) was significant: 50% (8 of 16) of males versus 13% (4 of 31) of females (P < 0.05, Fisher exact test).

Heterotopic mucosa was identified in six patients: gastric in five cases, and a combination of gastric and pancreatic in one. A carcinoid tumor was identified in one patient (1.5 cm in greatest dimension), and an incidental adenomyoma was found in another patient. Four complications (8.5%) were possibly attributable to the removal of the diverticula: two wound infections and two anastomotic leaks requiring exploration. Two of these complications (a wound infection and an anastomotic leak) occurred in female patients that were originally asymptomatic, one wound infection was in an asymptomatic male patient, and one anastomotic leak was in a symptomatic male patient (8.6% asymptomatic, 8.3% symptomatic morbidity). It should be noted that the two wound infections occurred in patients that had concomitant bowel resections, so it is not entirely clear if the wound infections were a result of removal of the diverticula.

Of 12 symptomatic patients, the surgical technique for Meckel removal consisted of diverticulectomies in 50% (n = 6), segmental ileal resections in 41.7% (n = 5), and unknown in 8.3% (n = 1). Of 35 asymptomatic patients, diverticula were removed by diverticulectomy in 71.4% (n = 25), segmental ileal resection in 25.7% (n = 9), and unknown in 2.9% (n = 1). Of the four patients who experienced complications, three (75%) underwent segmental ileal resection (two wound infections, one anastomotic leak). In the one other patient who experienced an anastomotic leak, the method of surgical removal was unavailable.

Discussion

In 1598, Fabricus Hildanus first described a small diverticulum, for which Johann Frederick Meckel described the embryological basis in 1809. (2,3) The development of this congenital gastrointestinal anomaly occurs with the failure of obliteration of the proximal vitelline duct during the 7th to 8th embryonic week. This diverticulum contains the normal layers of the small intestine and is categorized as a true diverticulum. Gastric mucosa was not discovered until 1904 by Salzer, followed shortly by the discovery of the association of the diverticulum with adjacent ulceration of the ileum by Deetz in 1907. (4-6) An additional 8 years after Deetz's discovery, Gramen described a clinical picture of Meckel diverticulum similar to appendicitis. (7) Malignancy associated with Meckel diverticulum was not reviewed until 1963 by Weinstein et al. (8)

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Meckel diverticulum is the most common congenital gastrointestinal anomaly, with an incidence of 1 to 2% based on autopsy series. (9) Male gender is predominant in many series. (1,4,9) This series differed in that there were twice as many female patients as males; however, this is probably secondary to routine removal by gynecologists at the time of hysterectomy and oophorectomy at this institution. Most series similarly report removal as a result of incidental discovery during an unrelated procedure. (1,4,9,10-12)

Although this series is predominantly female, twice as many male patients were symptomatic. The study by Cullen et al, (13) considered one of the classic works on this condition, found a similar prevalence of symptomatic males; however, a significant number of the cases were pediatric. Only three other studies dealing predominantly with adults were found in the literature. Only one study in the literature, by Peoples et al, (10) was focused exclusively on those over 18 years of age. The authors found three times as many males to be symptomatic as females. Although Peoples et al examined 94 cases, their subset of symptomatic patients was very small (4%) (Table 2).

Of those presenting with symptoms, obstructive complaints predominate in the adult. (14-16) Diverticulitis is found in up to 30% of symptomatic patients. (17) Acute bleeding is rare; case reports found in the literature exclusively describe massive lower gastrointestinal bleeding in adults. Most bleeding is relatively minor, but results in chronic anemia and is usually discovered after negative large bowel evaluation. Other rare presentations of this diverticulum include presence in a hernia sac (Littre hernia), as was seen in one of our patients, as well as associated malignancy. One patient in our series had a carcinoid tumor, but in general, malignancy is rarely found arising from Meckel. The most thorough description of malignancy in Meckel was done by Weinstein et al (8) where, in a series of 80 malignant cases, there were 35 sarcomas, 29 carcinoids, and 16 adenocarcinomas.

Heterotopic mucosa is found more frequently in symptomatic patients than during incidental removal (33% and 16%, respectively). (15) As was found in this series, gastric mucosa is the most frequent ectopic mucosa found, with pancreatic mucosa the second most common. (1)

In suspected symptomatic Meckel, preoperative evaluation includes a bleeding scan, technetium Tc 99m, which relies on the presence of ectopic gastric mucosa, with a reported sensitivity in adults of only 62%. (18) Other methods of evaluation have limited diagnostic usefulness. Groebli et al demonstrated this in their review of positive studies with the following modalities: small bowel barium, 4 (44%) of 9; technetium Tc 99m, 3 (75%) of 4; angiography, 1 (33%) of 3; and computed tomography, 1 (7%) of 14. (11) Hence, in symptomatic Meckel, surgical abdominal exploration is often warranted.

Whether or not to remove diverticula that are found incidentally is controversial. Postoperative morbidity and mortality depend on the indication for removal. When symptomatic, the mean mortality accepted is 6 to 7%, with a range of 2.5 to 15%; the mean acceptable level of postsurgical complications is 6 to 30%. (17) When removed incidentally, morbidity is estimated at 9%. While the mortality in the current series was zero, the morbidity falls near the estimated ranges, with an 8.6% morbidity in asymptomatic patients and an 8.3% morbidity in symptomatic patients (8.5% overall). Those supporting incidental removal feel the relatively high mortality and complication rates with symptomatic disease justifies the associated morbidity of elective removal. Opponents of incidental diverticulectomy quote the low (4.2%) lifetime risk of symptoms developing. (19)

It is interesting to note that the vast majority of incidental removal in this series occurred in female patients undergoing gynecological procedures; our data, however, indicate that women are less likely to develop symptomatic Meckel than men (12.9% versus 50%, P < 0.05). The carcinoma and adenomyoma were found in females, but the small number of these events makes it difficult to determine the significance of this finding. Also, two (50%) of the four postoperative complications directly related to the removal of the diverticulum occurred in asymptomatic women. Hence, incidental removal, particularly in the female population, may not be warranted. In the male population, Meckel symptoms, and associated morbidity, are more prevalent, perhaps supporting incidental removal. There has been some discussion (1) that symptoms are less likely to develop with increasing age, a trend that was noted in this population, although it was not an exceptionally strong trend. As only one other study (10) was found that dealt with Meckel solely in the adult population, it is difficult to ascertain the role patient age plays in symptom development. Hence, in the male population, whether or not to remove incidental diverticula is much less clear.

It should also be noted that three (75%) of four patients who suffered complications had segmental ileal resections, perhaps indicating that removal by diverticulectomy whenever possible is preferable, particularly in the asymptomatic patient.

In conclusion, in the adult population, Meckel diverticula are found infrequently with abdominal exploration. They rarely become symptomatic, but when symptoms do arise they can have significant associated morbidity and mortality. Complications directly attributable to diverticulum removal are uncommon; however, those that do occur can be life threatening. Therefore, incidental removal of asymptomatic diverticula, particularly in women, is not recommended.

Table 1. Patient and case characteristics (a)

                      Male                   Female

N                     16 (34%)               31 (66%)
Mean Age in yr        51.1 ([+ or -] 19.1)   56.5 ([+ or -] 17.8)
 ([+ or -] S.D.)      range 19-79            range 20-87
Asymptomatic           8 (50%)               27 (87%)
Symptomatic            8 (50%)                4 (13%)
  Obstruction          3                      1
  Diverticulitis       4                      4
  Acute hemorrhage     1                      0
Heterotopic Mucosa     3 (19%)                3 (10%)
  Gastric              2                      3
  Gastric and          1                      0
   pancreatic
Carcinoma              0                      1
Adenomyoma             0                      1
Complications          2                      2
  Anastomotic leak     1                      1
  Wound                1                      1
   infection (b)

                                                   P
                            Total                  value

N                           47 (100%)              0.04
Mean Age in yr              54.7 ([+ or -] 18.2)   NS
 ([+ or -] S.D.)            range 19-87
Asymptomatic                35 (74.5%)             0.01
Symptomatic                 12 (25.5%)             0.01
  Obstruction                4
  Diverticulitis             8
  Acute hemorrhage           1
Heterotopic Mucosa           6 (12.8%)             NS
  Gastric                    5
  Gastric and                1
   Pancreatic
Carcinoma                    1 (2.1%)              NS
Adenomyoma                   1 (2.1%)              NS
Complications                4 (8.5%)              NS
  Anastomotic leak           2
  Wound                      2
   infection (b)

(a) NS, not significant, or in some cases significance not tested due
to small N.
(b) Possibly due to concomitant bowel resection.

Table 2. Comparison of studies on Meckel diverticulum in the adult

                                   No. w/surgical    Symptomatic vs.
Study (age range in years)         management (a)    asymptomatic

Peoples, et al (10) (19-82)         94               Sym = 4
                                                     Asym = 90
Groebli, et al (11) (16-87)        119               Sym = 52
                                                     Asym = 67
Leijonmarck, et al (12) (16-87)    231 (b)           Sym = 109
                                                     Asym = 122
Cullen, et al (13) (<1-86) (c)     145               Sym = 87
                                                     Asym = 58
Current study (19-87)               47               Sym = 12
                                                     Asym = 35

                                   M:F ratio in  Ectopic
Study (age range in years)         symptomatic   mucosa   Carcinomas

Peoples, et al (10) (19-82)        3:1           NA       NA
Groebli, et al (11) (16-87)        3:1           32       4
                                                          (Carcinoid)
Leijonmarck, et al (12) (16-87)    1.8:1         56       4
Cullen, et al (13) (<1-86) (c)     2.4:1         NA       NA
Current study (19-87)              2:1            6       1
                                                          (Carcinoid)

                                   Symptomatic        Asymptomatic
                                   postop comp        postop comp
Study (age range in years)         rate (surg mgt.)   rate (surg mgt.)

Peoples, et al (10) (19-82)        Mortal = 0%        Mortal = 2%
                                   Morbid = 0%        Morbid = 2%
Groebli, et al (11) (16-87)        Mortal = 0%        Mortal = 0%
                                   Morbid = 10%       Morbid = 9%
Leijonmarck, et al (12) (16-87)    Mortal = 0%        Mortal = 0.8%
                                   Morbid = 2%        Morbid = 6%
Cullen, et al (13) (<1-86) (c)     Mortal = 2%        Mortal = 1%
                                   Morbid = 12%       Morbid = 2%
Current study (19-87)              Mortal = 0%        Mortal = 0%
                                   Morbid = 8.3%      Morbid = 8.6%

(a) Patients with either diverticulectomy, segmental ileal resections,
or wedge ileal resections.
(b) Total study number was 260, but this included 28 cases with Meckel
diverticulum left in situ, and one case discovered at autopsy.
(c) Study includes several children, but is considered one of best
series in the literature. Included for reference purposes.

Acknowledgment

We would like to thank Dr. James Kessel for his contributions to this project.

Accepted January 8, 2004.

Please see Kevin E. Behrns' editorial on page 1029 of this issue.

References

1. Yamaguchi M, Takeuchi S, Awazu S. Meckel diverticulum: investigation of 600 patients in Japanese literature. Am J Surg 1978; 136:247-249.

2. Moore KL. The Developing Human: Clinically Oriented Embryology, Philadelphia, WB Saunders Co., 1988, ed 4, pp 235-237.

3. Meckel JF. Ueber die Divertikel am Darmkanal. Arch Die Physio 1809;9:421-453.

4. Turgeon DK, Barnett JL. Meckel diverticulum. Am J Gastroenterol 1990;85:777-781.

5. Salzer H. Uber das Offene Meckelesche Divertikel. Wien Klien Wochnenschr 1904;17:614-617.

6. Deetz E. Perforationsperitonitis von einem Darmdivertikel mit Magenscleimhautbau ausgenhend. Deutsh Ztsch Chir 1907;88:482-493.

7. Gramen K. Chronischen Ulcus in einem Meckelshen Divertikel mit Perforation und Diffuser Peritonitis. Nord Med Ark Kirurgi 1915;48:1.

8. Weinstein EC, Docherty MB, Waugh JM. Neoplasms of Meckel diverticulum. Int Abstracts Surg 1963;116:103-111.

9. Perne AS. Meckel diverticulum. N Engl J Med 1959;260:690.

10. Peoples JB, Lichtenberger EJ, Dunn MM. Incidental Meckel diverticulectomy in adults. Surgery 1995;118:649-652.

11. Groebli Y, Bertin D, Morel P. Meckel diverticulm in adults: retrospective analysis of 119 cases and historical review. Eur J Surg 2001;167(7):518-524.

12. Leijonmarck CE, Bonman-Sandelin K, Frisell J, et al. Meckel diverticulum in the adult. Br J Surg 1986;73:146-149.

13. Cullen JJ, Kelly KA, Moir CR, et al. Surgical management of Meckel's diverticulum. Ann Surg 1994;220(4):564-569.

14. Root GT, Baker CP. Complications associated with Meckel diverticulum. Am J Surg 1967;11:285-288.

15. Rutherford RB, Akers DR. Meckel diverticulum: a review of 148 pediatric patients with specific reference to the pattern of bleeding and to mesodiverticular vascular bands. Surgery 1966;59:618-626.

16. Weinstein EC, Cain JC, Remine W. Meckel diverticulum: 55 years of clinical and surgical experience. JAMA 1962;182:251-253.

17. Mackey WC, Dineen P. A fifty-year experience with Meckel diverticulum. Surg Gynecol Obset 1983;156:56-64.

18. Lin S, Suhocki PV, Ludwig KA, et al. GI bleeding in adult patients with Meckel diverticulum: the role of technetium 99m pertechnetate scan. South Med J 2002;95(11):1338-1341.

19. Soltero MJ, Bill AH. The natural history of Meckel diverticulum and its relation to incidental removal. Am J Surg 1976;132:168-173.

RELATED ARTICLE: Key Points

* Meckel diverticulum is a rare disorder in adults.

* Adults with Meckel diverticulum are often asymptomatic, but symptoms that do arise are associated with significant morbidity.

* Complications from diverticulum removal are uncommon, but are often life threatening; incidental removal of asymptomatic diverticula, particularly in women, is therefore not recommended.

Patrick A. Stone, MD, Matthew J. Hofeldt, MD, John E. Campbell, MD, Geetha Vedula, BA, John A. DeLuca, MD, and Sarah K. Flaherty, BS

From the Charleston Area Medical Center, West Virginia University (Charleston Division); West Virginia University School of Medicine; and the Center for Health Services & Outcomes Research, Charleston Area Medical Center Health Education and Research Institute, Charleston, WV.

Reprint requests to Patrick A. Stone, MD, West Virginia University (Charleston Division), Department of Surgery, 3110 MacCorkle Avenue, Charleston, WV 25304. Email: [e-mail]