Endometriosis is a condition in which tissue similar to the uterine lining grows outside the uterus. Appendicitis is inflammation of the appendix. Because both conditions can cause severe abdominal pain, they can be hard to tell apart.
However, both endometriosis and appendicitis may cause additional symptoms, which can help doctors differentiate one condition from the other. A physical examination and other diagnostic tests can also help doctors make an accurate diagnosis and provide appropriate treatment.
This article gives an overview of endometriosis and appendicitis and covers the symptoms and causes of each condition and the available treatment options. We also provide a brief summary of how to tell the difference between these two conditions.
Endometriosis is a disease in which tissue similar to the lining of the uterus grows outside the uterus. According to the World Health Organization (WHO), endometriosis is common, affecting around
Appendicitis is inflammation of the appendix, a small, tube-shaped sac near the junction between the small and large intestines. A 2018 research review suggests that the appendix may play a role in immunity or serve as a reservoir for healthy gut bacteria.
Appendicitis is common, affecting
Although endometriosis can occur in males who receive high doses of estrogen as a treatment for prostate cancer, the vast majority of cases occur in females. Conversely, appendicitis is
Moreover, while endometriosis tends to occur in people
Both endometriosis and appendicitis can cause severe abdominal pain and digestive issues. For this reason, the two conditions can sometimes be difficult to tell apart.
However, each condition may cause additional symptoms. Some of these symptoms are more likely to occur in one condition than in the other, and this can help doctors to make a differential diagnosis.
Endometriosis
Pain is the
- very painful menstrual cramps
- painful bowel movements during a period
- painful urination during a period
- chronic pain in the lower back and pelvis
- pain during or after sex
Endometriosis pain occurs when the endometrial tissue outside the uterus swells and bleeds during menstruation. Unlike the tissue inside the uterus, the endometrial tissue that is shed outside the uterus is unable to leave the body with ease. This can lead to complications such as:
- inflammation
- blocked fallopian tubes
- ovarian cysts
- adhesions, which are a type of scar tissue that fuses organs together
- intestinal and bladder problems
Other possible symptoms of endometriosis include:
- bleeding or spotting between periods
- digestive problems that worsen during menstruation, such as:
- bloating
- nausea
- diarrhea
- constipation
- infertility
Appendicitis
Appendicitis is the
Abdominal pain from appendicitis tends to be sudden and severe and may worsen within hours. The pain typically begins near the belly button and may radiate to the lower right abdomen. It may worsen with the following activities:
- moving
- breathing deeply
- coughing
- sneezing
Other possible symptoms of appendicitis
- loss of appetite
- nausea
- vomiting
- abdominal swelling
- fever
- bowel problems, such as:
- an inability to pass gas
- constipation
- diarrhea
Appendicial endometriosis
One condition that may further complicate a doctor’s ability to differentiate endometriosis and appendicitis is appendicial endometriosis (AE). As a 2022 case report explains, this is a rare form of endometriosis in which tissue similar to the lining of the uterus grows on the appendix. The symptoms may present as acute appendicitis.
In this case study, a person experienced the following symptoms:
- sudden, generalized abdominal pain
- nausea
- vomiting
- chills
The authors of a 2023 research review assessed the prevalence of AE among women with endometriosis or pelvic pain. They found that 2.67% of women who were admitted to a hospital with acute appendicitis had AE. Separately, AE was an incidental finding among 7.23% of women who underwent gynecological surgery.
Appendicitis typically causes pain in the lower right abdomen, and this may help differentiate it from endometriosis in some cases. However, endometriosis may also cause lower right abdominal pain if it affects structures in the lower right side of the abdomen, such as the right fallopian tube or right ovary.
Symptoms that are common in appendicitis and less common in endometriosis include:
- loss of appetite
- vomiting
- chills
Doctors may need to perform a pelvic exam and additional diagnostic tests to make an accurate diagnosis.
The table below outlines the key similarities and differences between endometriosis and appendicitis.
| Endometriosis | Appendicitis | |
|---|---|---|
| Pain symptoms | • very painful menstrual cramps • painful bowel movements during menstruation • painful urination during menstruation • pain during or after sex • chronic lower back or pelvic pain | • sudden, severe pain that starts near the belly button and radiates to the lower right abdomen • pain that worsens with movement, deep breathing, or coughing • pain that worsens within hours |
| Other symptoms | • bleeding or spotting between periods • infertility • bloating • constipation • diarrhea • nausea | • loss of appetite • nausea • vomiting • abdominal swelling • fever • an inability to pass gas • constipation • diarrhea |
| Possible causes | • retrograde menstruation, in which some period blood flows through the fallopian tubes and into other parts of the body during a period • immune system issues in which the immune system is unable to effectively locate and destroy endometrial tissue growing outside the uterus • abdominal surgery, which may accidentally transplant endometrial tissue into areas outside the uterus • increased estrogen levels • genetic factors | • hard stools or growths that can block the opening of the appendix • an infection in the digestive tract • inflammatory bowel disease (IBD) |
| Diagnostic tests | • pelvic examination • ultrasound scan • MRI scans • laparoscopy • medications such as hormonal birth control or gonadotropin-releasing hormone (GnRH) agonists | • physical examination • blood and urine tests to rule out other conditions • abdominal ultrasound • MRI scans • CT scans |
| Treatment options | • hormonal birth control • GnRH agonists • surgery to remove patches of endometrial tissue • pain medication | • appendectomy (surgery to remove the appendix) • antibiotics |
Endometriosis and appendicitis require different treatment approaches.
Endometriosis treatments
Treatments for endometriosis
- Nonsteroidal anti-inflammatory drugs (NSAIDs): These medications can help reduce pain and inflammation associated with endometriosis. Examples include:
- ibuprofen
- diclofenac
- acetylsalicylic acid
- Opioid pain relievers: These are prescription-only pain medications that doctors may prescribe to help treat severe endometriosis pain during a person’s monthly period.
- Hormone therapy: Doctors may recommend hormone therapy to help reduce levels of certain hormones that may cause or contribute to endometriosis, but these treatments are not suitable for people who would like to become pregnant. Examples include:
- progestins
- birth control pills
- GnRH agonists
- Surgery: Surgery to remove endometrial tissue in the ovaries can help relieve mild to moderate endometriosis pain. However, in around
20%Trusted Source of cases, the endometrial tissue grows back within 5 years of the surgery.
Appendicitis treatments
According to the
Surgery reduces the risk of the appendix bursting and causing additional complications, such as peritonitis, which is inflammation of the inner lining of the abdomen. Peritonitis can be life threatening without emergency treatment.
Doctors will give a person antibiotics before surgery. If a person has a mild case of appendicitis that improves with antibiotics, they may not need follow-up surgery.
Endometriosis is a condition in which tissue similar to the lining of the uterus grows outside the uterus. Appendicitis is inflammation of the appendix. Both conditions are common and may cause severe abdominal pain.
Because of these similarities, doctors may have difficulty telling the two conditions apart based on symptoms and a physical examination alone. Moreover, some people may experience appendicial endometriosis, in which endometrial tissue grows on the appendix.
To differentiate endometriosis and appendicitis, doctors may use diagnostic tests such as abdominal imaging, blood tests, and urine analysis. An accurate and timely diagnosis is essential to providing effective treatment.
The treatment for endometriosis may differ from person to person, but treatment options include NSAIDs, hormone therapy, and surgery to remove endometrial tissue.
The standard treatment for appendicitis involves antibiotics and surgery to remove the appendix. However, in cases of mild appendicitis that improve with antibiotics, a person may not need the follow-up surgery.
