Mesenteric Adenitis - Causes, Symptoms, Diagnosis, and Treatment

Introduction

Small groups of cells called lymph nodes filter and capture pathogenic viruses and bacteria while defending the body against illnesses. They can be found all over the body, although they are most common in the armpit, neck, chest, and belly. A tissue fold known as the mesentery joins the intestine to the abdominal wall. Mesenteric adenitis is the medical term for inflammation of the mesentery's lymph nodes. It is a rare condition and mostly resolves on its own. Mesentery is the tissue that joins the intestines to the abdominal wall, and mesentery adenitis, also known as mesenteric lymphadenitis, is a medical disorder marked by inflammation and swelling of the lymph nodes in the mesentery. It is crucial to detect and comprehend this disorder because its symptoms might be mistaken for those of other abdominal conditions, like appendicitis. The causes, signs, symptoms, diagnosis, and potential therapies of mesenteric adenitis will all be covered in this introduction.

Who Is Most Affected by Mesenteric Adenitis?

Mesenteric adenitis or mesenteric lymphadenitis is more common in children and adolescents. It rarely occurs after the age of 20 years. It is often misdiagnosed as appendicitis due to similar clinical features of right abdominal pain. Mesenteric adenitis, which predominantly affects children and young people, is a somewhat common but sometimes disregarded illness. It is defined by the swelling of the lymph nodes in the abdomen mesentery, and because it presents with similar symptoms to more dangerous disorders like appendicitis, it is sometimes misdiagnosed as such.

How Does Mesenteric Adenitis Differ From Appendicitis?

An appendix is a small organ attached to the large bowel (intestine) on the right lower side of the abdomen. The inflammation of the appendix due to any infection is called appendicitis. It causes sudden pain around the belly button and spreads to the right lower side of the abdomen. Nausea, vomiting, loss of appetite, and low-grade fever are a few other symptoms. The clinical features are similar to mesenteric adenitis, especially in children. However, the pain on palpation of the abdomen during the physical examination is high compared to mesenteric adenitis. In addition, an abdominal ultrasound is essential in confirming the diagnosis.

What Causes Mesenteric Adenitis?

The leading cause of mesenteric adenitis is listed down:

• Viral infections include gastroenteritis (inflammation of intestinal linings) or stomach flu.

• Bacterial species like Yersinia pseudotuberculosis and Yersinia enterocolitica commonly cause mesenteric adenitis. And other species like E.coli, Salmonella, and Streptococcus are also found to cause inflammation of mesenteric lymph nodes.

Mesenteric adenitis is classified according to the causative factor as follows:

• Primary Mesenteric Adenitis: It is the swelling of lymph nodes that occurs due to an unknown cause.

• Secondary Mesenteric Adenitis: Mesenteric adenitis occurs in response to the inflammation of intra-abdominal organs (gallbladder, pancreas, bile duct, etc.) due to any bacterial or viral infection.

What Are the Signs and Symptoms of Mesenteric Adenitis?

Mesenteric adenitis is often diagnosed in children under ten. They tend to complain of lower right abdominal pain. It usually occurs in association with stomach flu or respiratory infections.

The typical symptoms of mesenteric adenitis include:

• Pain in the right lower abdomen usually begins from the belly button.

• Fever.

• Nausea and vomiting.

• Changes in bowel habits.

How Is Mesenteric Adenitis Diagnosed?

• Physical Examination: The physician palpates the abdomen to assess the degree of pain. A detailed medical history of the child is taken regarding any previous infections.

• Blood Examination is to evaluate the complete blood count. The levels of white blood cell (WBC) and C-reactive protein (CRP) are increased in children with mesenteric adenitis.

• Urinalysis involves the screening of urine samples. It is not used as a confirmatory diagnosis. However, it helps in excluding urinary tract infections if present.

• Computed Tomography (CT) of the abdomen shows a detailed image of the enlarged clusters of lymph nodes in the mesentery.

• Ultrasound Imaging of the abdomen is the standard technique used in diagnosing mesenteric adenitis and differentiating it from other disorders. The imaging shows enlarged and denser mesenteric lymph nodes and an absence of appendix inflammation. Any of the lymph nodes is enlarged to 8 mm or more in size. However, in appendicitis, the lymph nodes are smaller than those in mesenteric lymphadenitis.

• Superb Microvascular Imaging (SMI) provides a detailed image of the microvascular blood flow. It increases the accuracy and specificity of mesenteric adenitis diagnosis when used along with ultrasonography. It also provides a better image resolution than color Doppler imaging.

What Are the Differential Diagnoses of Mesenteric Adenitis?

The disorders that possess characteristic features similar to mesenteric adenitis are discussed below:

• The term "inflammatory bowel disease" describes an infection of the digestive system. The abnormal immune response causes it. The symptoms include diarrhea, fatigue, weight loss, and abdominal pain. Various imaging modalities are available to confirm such disorders.

• Endometriosis: The endometrium is the term for the uterus lining. In endometriosis, a lining resembling endometrium develops outside the uterus. The clinical features are abdominal and lower back pain, pain during intercourse, diarrhea, constipation, etc. Ultrasound imaging is commonly used in diagnosis.

• Pelvic Inflammatory Disease involves the infection of female reproductive organs like the cervix, ovaries, uterus, and fallopian tubes. As a result, the women suffer from pain in the lower abdomen, pain during intercourse, fever, foul-smelling vaginal discharge, and bleeding.

What Are the Complications of Mesenteric Adenitis?

Mesenteric adenitis is not a severe condition and mostly resolves on its own. Rarely does it lead to the following complications:

• Dehydration occurs in excessive loss of body fluids due to diarrhea and vomiting.

• Abscess formation if adenitis is left untreated.

• If the infection spreads to the membrane covering abdominal organs, it causes peritonitis.

How to Treat Mesenteric Adenitis?

The recovery of children with mesenteric adenitis occurs within weeks. However, supportive care is essential as follows:

• To treat pain and fever, non-steroidal anti-inflammatory medications such as ibuprofen and acetaminophen are advised.

• Intravenous administration of fluids is done in case of dehydration.

• Other lifestyle modifications include drinking plenty of fluids, resting, and applying moist heat to the abdomen to relieve the pain.

Can Mesenteric Adenitis Be Prevented?

The risk of acquiring mesenteric adenitis is reduced by practicing the following methods:

• Washing hands frequently with soap and water to keep them clean.

• Avoid close contact with the sick person.

• Maintaining a clean and hygienic living space to prevent unnecessary infection.

Conclusion

Mesenteric adenitis is a rare condition and is often misdiagnosed as acute appendicitis. A precise physical examination along with imaging techniques aids in the accurate diagnosis. The prognosis of mesenteric adenitis is significantly good in children with early diagnosis and treatment.