Appendicular Plastron: Causes, Evolution, Symptoms, Diagnosis, Treatment and Complications

This inflamed mass indicates an inflamed and in many cases perforated appendix that is detected on palpation of the right iliac fossa.

It is formed by the adhesion of loops of the small intestine and the greater omentum around the inflamed appendix , as a defensive response, limiting peritonitis and forming a mass that blocks the infectious process.

An appendicular plastron is manifested by a violent and painful appendicitis, it is a painful mass located in the right iliac fossa, the signs of which may diminish after a few days, but in reality they never disappear.

It is very important that it is treated as soon as possible because it tends to get worse and cause serious damage.

The appendicular plastron is a clinical sign that is evident on abdominal palpation, which points to a resistant, painful and poorly defined mass, giving the sensation of a wall shield.

The appendicular plastron takes several days to accumulate and can rupture in the abdominal cavity, but it can also regress with proper medical treatment.

Causes of the appendicular plastron

It is generally found in certain infectious or inflammatory pathologies and corresponding to inflammation of the omental fat.


When inflammation remains confined to the wall of the appendix, it can progress and spread, resulting in serious or complicated forms such as:

An appendicular plastron: the infection extends to the entire lower abdomen and is associated with intestinal transit disorders. This plastron can heal or evolve into an appendicular abscess.

An appendicular abscess: A pus-filled cavity forms in the appendix. The fever becomes very high and the general condition of the patient is altered. Surgical drainage of the abscess is urgently needed to prevent the abscess from rupturing.

A peritonitis: The abscess breaks into the peritoneum (lining that surrounds all the abdominal organs). The pain increases sharply and spreads rapidly to the entire abdomen.

Surgical treatment is urgently needed, as peritonitis can progress to death from systemic organ infection or organ failure.


Acute ulcerative, phlegmonous, or gangrenous appendicitis tends to perforate, which can progress to a palpable plastron or mass.

Constipation , gas cessation, states of nausea and vomiting, fever of 38 to 38.5 ° C and tachycardia occur .

Diagnosis of the appendicular plastron

It occurs at least 5 to 7 days after acute appendicitis.

On physical examination, when gently palpating, a mass was perceived in the right iliac fossa, painful on palpation, with poorly defined limits.

The rest of the abdomen is painless on palpation and there is no evidence of generalized peritonitis.

The ultrasound shows a magma of intestinal loops (small intestine or terminal ileum), omentum and colon, sometimes with a collection deep within the shell that signifies the evolution towards the abscess.

Some contributing biological tests are leukocytosis, C-reactive protein, and bilirubin.

An ultrasound and a CT scan are performed to differentiate if it is a phlegmon or an abscess.

  1. Appendicular phlegmon: it is a solid inflammatory mass that lacks pus. It is located in the lower right area of ​​the appendix and whose liquid content is found within the intestinal loops.
  2. Appendicular abscess: it is a hypodense structure, which may or may not present gas bubbles, and where a liquid pattern dominates, corresponding to pus. It is a pocket that is around the appendix that presents an acute inflammation.

Treatment of the appendicular plastron

The most widely used, appropriate and effective treatment is cefuroxime.

The evolution of the plastron should be followed to evaluate a therapeutic failure or a complication.

It is also possible to consider surgery as an appendectomy that can be performed when there is no response to antibiotic treatment and clinical symptoms persist.

An appendicular plastron is currently approached laparoscopically.

It is defined by the perception of a palpable mass whose limits are best specified by ultrasound.

There is an operational difficulty of these inflammatory masses; however, with the help of patiently managed hydrodissection, the procedure can be completed.

The extraction of the piece requires the establishment of an extraction bag, since there is a risk of purulent dissemination during the opening of the abscessed area.

This risk can be minimized by prior transparietal puncture under laparoscopic control and by using the vacuum cleaner as a palpation and dissection instrument.

In these complicated forms of acute appendicitis (plastron, abscess, peritonitis), drainage is often necessary to remove the pus and perform postoperative antibiotic treatment.


The consequences of not treating the appendicular plastron in time is that it triggers peritonitis, presenting a septic shock caused by the release of toxins and bacteria.

On the other hand, there may be: hypovolemia, hypoxia and metabolic acidosis, renal failure due to lack of perfusion and action of circulating toxins.

Dry tongue, cyanosis of the hands, fecal vomiting, mental clouding, organ failure, dehydration, respiratory distress, collapse and even death are observed.