Appendicitis: Symptoms, Causes, and Treatment

Appendicitis is a very common condition throughout the world and can become complicated if left untreated. Keep reading to find out more.
Appendicitis: Symptoms, Causes, and Treatment
Diego Pereira

Written and verified by el médico Diego Pereira.

Last update: 17 May, 2023

Appendicitis is one of the most frequent reasons for surgery worldwide. It consists of inflammation of the vermicular appendix, a small structure of the gastrointestinal system.

It’s well-known due to the very specific symptoms it presents, despite the fact that on some occasions, the diagnostic process may be hindered by anatomical variations or some differential diagnoses. If you want to know a little more about this disease, we’ve prepared the following article. Keep reading!

What are the main symptoms?

Appendicitis has a typical pattern of presentation that’s closely related to the anatomical location of the appendix. It’s a small organ in relation to the cecum, the first portion of the colon. It’s located near the ileocecal junction, the site where the small intestine connects to the large intestine.

In the vast majority of cases, this area is in the lower right quadrant of the abdomen and is called the right iliac fossa. However, the pain doesn’t always start there. Sometimes a feeling of discomfort begins in the epigastrium before radiating to the right iliac fossa.

The epigastrium is the middle and upper quadrant of the abdomen, that is, the one that’s above the navel. That’s why, at first, many people can confuse the pain with gastritis or a peptic ulcer.

Additional manifestations

In addition to pain (which is usually sharp and intense), there are other associated symptoms such as those described below:

  • Fever: Can be very high, whether or not it’s preceded by chills.
  • Loss of appetite, also called hyporexia.
  • Nausea and vomiting.
An image of the appendix and the intestines.
The appendix is an anatomical structure located at the junction of the small and large intestines.

Why does appendicitis occur?

The appendix is a hollow organ, which means that it has a cavity inside. This is common throughout the entire digestive tract. Being so small, it’s more or less easy for it to become clogged by things inside or outside the GI tract.

A good part of the cases of appendicitis is associated with the presence of fecaliths, which are small particles of very hard feces. They occur in patients with chronic constipation, in whom it’s normal to produce this texture.

Of course, there are also associated dietary factors, such as the consumption of seeds and small objects. Intestinal parasites and the growth of lymphoid tissue around the appendix can also cause obstruction.

How does the appendix become inflamed?

Once the obstruction occurs, the increase in pressure within the appendix leads to the interruption of blood flow around the organ. This results in the progressive death of the cells found in its wall with an associated inflammatory phenomenon.

Later, some bacteria present within the lumen of the intestine can penetrate the walls of the appendix and cause local infections. Organ perforation and the inflammatory process lead to difficult-to-manage clinical pictures such as abdominal abscesses and peritonitis.

How common is appendicitis?

In most of the world, it’s the most common emergency surgical illness. This can be explained by the very particular characteristics of its anatomy, mentioned in the previous section.

In fact, it’s interesting that during some abdominal procedures (for any other reason) the removal of the appendix (appendectomy) is performed preventively, due to the high risk of developing the disease in almost all age groups.

It tends to be a little more common in those countries with a high prevalence of constipation. This happens due to diets with little fiber, water, and vegetable content.

How is appendicitis diagnosed?

Even when symptoms present characteristically, in some patients, a diagnostic dilemma may exist. This happens, above all, in women.

In addition to the physical examination and the medical history, the following complementary tests could be requested to reach a more accurate diagnosis:

  • Complete blood cell count (CBC) or complete hematology (HC): Allows doctors to assess the white blood cell count and hemoglobin values.
  • Acute phase reactants: They’re measured in the blood and the most commonly used are ESR and PCR, which make it possible to determine if there’s an active inflammatory process.
  • Abdominal ultrasound: Allows for the visualization of inflammatory signs around the appendix, although it’s not always visible.
  • Simple abdominal X-ray: Rarely requested, but it aims to observe the cause of the obstruction.

In women

As we mentioned before, the diagnostic process in women can be more complicated than in men. This is due to the abundance of anatomical elements present in the pelvic region of women, which are also susceptible to inflammation and require surgery.

These organs include the uterus, fallopian tubes, and ovaries. For various reasons, any of these can become infected and cause profuse pain, fever, and vomiting.

Some of the conditions that most confuse doctors are pelvic inflammatory disease, salpingitis, ovarian abscesses, and ectopic pregnancies. For this last reason, a pregnancy test may be requested before any operation is performed.

Complementary studies are usually used to determine the origin of the pain. For example, a transvaginal ultrasound could provide valuable information for the diagnosis of gynecological infections that are mimicking appendicitis.

In men

Due to the absence of the aforementioned organs, the presentation of classic symptoms of appendicitis in a man doesn’t usually lead to diagnostic doubts. However, it’s not always so easy.

On some occasions, the appendix can be located in different areas within the abdominal cavity. This can be on the opposite side (that is, in the left lower quadrant) or below the liver.

As presented in a case review published in 2015, left-sided appendicitis is rare, but it can happen. In such circumstances, only certain imaging studies such as computed tomography can provide sufficient information.

The surgical removal of the appendix.
Surgical intervention is the final solution for the disease.

What’s the treatment for appendicitis?

Despite the fact that it’s an inflammatory and infectious process that can be alleviated with the administration of intravenous antibiotics, a case of appendicitis won’t be solved in this way. A surgical procedure known as an appendectomy is necessary.

This is an emergency procedure, which doesn’t mean that it should be done immediately. If the symptoms have a very short evolution time, doctors indicate the aforementioned studies to achieve diagnostic clarity.

Laparoscopic appendectomy: The great favorite

This procedure is currently the preferred technique and consists of making a small abdominal incision through which devices with an optical lens are inserted, as described in scientific studies. This allows for the visualization of the cavity in a quite acceptable way.

Laparoscopy has fewer complications and allows for various procedures, such as cholecystectomies, sterilizations, and pancreatectomies. Despite this, it requires fairly good technique on the part of the surgeon.

In addition, it can also be performed for exploratory and diagnostic purposes. This is because, due to the small incision, it’s a minimally invasive intervention.

When to go to the doctor?

The main symptom of appendicitis is abdominal pain in the right iliac fossa. If you experience this problem, the diagnosis is quite likely. As the hours go by, the rest of the aforementioned signs are added.

In these cases, you need to go to an emergency service as soon as possible. Depending on the hospital, the first may be with a family doctor or emergency specialist. However, you will then be referred to a specialist in general surgery and the digestive system, who will take over.



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