What is Meckel's Diverticulum? [Topic review + Clinical Case Discussion]

It's named after the doctor Johann Meckel, who in 1809 first described this defect; wich are sac-shaped evaginations located on the antimesenteric edge of the small intestine; sometimes a portion of heterotopic mucosa (normal tissue with abnormal localization) is also present in Meckel's diverticulum, which leads to possible complications; gastric and pancreatic tissue being the most frequent types, and although the presence of this heterotopic tissue is rare, they're almost always present (especially gastric) in the symptomatic cases of the pathology.

As for the epidemiology, it's the most frequent of all pathologies of the omphalomesenteric duct, and can be present in up to 2% of the population, there's also a certain frequency inclination towards the male genre, with a 4: 1 ratio compared to female.

• CLINICAL MANIFESTATIONS:

The clinical picture is diverse, and depends on age of the patient; a mnemonic is often used to describe the main features of the pathology, known as "the 2" rule, which refers to: 2% of the population, less than 2 feet from the ileocecal valve, 2 types of heterotopic mucosa (gastric and pancreatic), patients under 2 years of age, and 2 inches long.

In a considerable percentage of patients with this defect, it's asymptomatic unless it gets complicated; being the main clinical pictures (consequence of complications), hemorrhage, obstruction and inflammation. Hemorrhage and obstruction are very common in children of younger age, compared to inflammatory conditions (these are usually more common in children older than 5 years old). And there are less frequent complications that have been recorded, such as the origin of a neoplasm at the level of the diverticulum, that it's the site of impact of a foreign body, or the development of a parasitic infection.

• INFLAMMATION OF MECKEL'S DIVERTICLE:

The most frequent signs and symptoms include migratory abdominal pain and umbilical redness (Nicola's Sign), product of the spread of inflammation to the abdominal wall when there's a fibrous cord; The presence of both are signs that make us suspect the presence of this pathology.

• TREATMENT:

Regarding the performance of an Incidental Diverticulectomy, it's an objective issue of controversy; since the probabilities of whether or not it is counterproductive are evaluated, due to the fact that both the morbidity and mortality derived from the process should be compared with the probability that the diverticulum induces symptoms and subsequently complications.

However, in those symptomatic cases, especially in inflammatory conditions, the surgical approach is essential.

During a guard by the Pediatric Surgery Service I had the opportunity to be invited to observe an operation that had previously been electively scheduled for a different day, the surgery was scheduled to take place within a month or so; It was an 11-month-old male patient who had a history of digestive hemorrhage and where he had the presumptive diagnosis of Meckel's diverticulum.

However, given an acute picture of two days of evolution characterized by abdominal pain of strong intensity expressed through continuous crying and rejection of food, fever quantified at 38.5 ° C, and vomiting in number of 5 and both food and bilious content; it's decided to enter the patient to investigate the cause of the current clinical picture.

Laboratory results are obtained that yield a leukocytosis, with figures of 12,800 xmm3 at the expense of segmented, rest of complete hematology within normal limits; liver enzymes and renal function tests within normal limits in the same way.

Given the clinical suspicion of a possible Meckel diverticulum, due to the history of gastrointestinal bleeding and examinations performed during the first episodes, and the current clinical picture and suggestive laboratory tests, it's decided to surgically intervene in the patient under the diagnosis of Diverticulitis.

During the surgery a Meckel diverticulum was found approximately 1 foot and 5.7 inches from the ileal-cecal valve, (as mentioned during the discussion of the subject, in most cases the distance between the diverticulum and the valve it's less than 2 feet).

Resection of the diverticulum was performed with two-plane ileal-ileal terminal anastomosis.

And it was decided to carry out in the same way an incidental appendectomy through trans umbilical incision, (since the clinic of both entities is usually very similar as previously explained, and the coexistence of both clinical conditions is not common, but it have been cases reported).

Meckel's diverticulum is a pathology of variable incidence, which is related to an accident or error during embryogenesis of the yolk sac, this under normal conditions should be obliterated and disappear completely in intrauterine life; the permanence of it results in the development of a group of diseases known as pathologies of the omphalomesenteric duct, where Meckel's diverticulum occupies the first place in frequency.

It involves the formation of a group of sac-shaped evaginations located on the antimesenteric edge of the small intestine, at a distance from the ileal-cecal valve that does not exceed 2 feet. Children under two years of age are usually affected symptomatically, since after this age, patients who present with the diverticulum usually evolve subclinically into adulthood, usually without complications.

Among the most common complications are digestive hemorrhages, intestinal obstructions, the inflammatory condition, or the development of neoplasms or infections at the level of the diverticulum.

As explained during the discussion of the topic and the clinical case presented, many times patients can take more than one complication at the same time: such was the case of the described patient, who had presented a history of gastrointestinal bleeding during his short life, and It was subsequently complicated by an inflammatory condition, which is why an emergency intervention was necessary (although inflammation of the diverticulum is usually more frequent in older children, we see how there are always exceptions to the rule).

It's very important to know about this type of surgical pathologies, and its variety of clinical presentations, in order to be able to make a timely and early diagnosis, and thus provide adequate treatment to the patients, to preserve their lifes and health.

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