Overview.
An inflammation of the mesenteric lymph nodes that may be caused by viral or bacterial infections.
Typical symptoms are fever, abdominal pain and vomiting, sometimes accompanied by diarrhea or constipation.
The cause of the disease is not clear, but is generally believed to be caused by viral infections.
Conservative treatment, such as bed rest and symptomatic treatment, is the mainstay.
Definition
Nonspecific mesenteric lymphadenitis is a nonspecific inflammation of the lymph nodes in the mesentery of the ileum and colon, which is common in children and adolescents, and may also occur in adults.
It is generally recognized as an acute inflammation of the mesenteric lymph nodes caused primarily by viral infections, often complicating upper respiratory tract infections or intestinal infections [1-2].
Classification
Classification according to the urgency of onset
Acute nonspecific mesenteric lymphadenitis
Acute non-specific mesenteric lymphadenitis often occurs suddenly during or after the course of upper respiratory tract infections such as colds, tonsillitis, etc., and may occur after intestinal inflammation in some patients.
Chronic non-specific mesenteric lymphadenitis
Most of the patients with acute non-specific mesenteric lymphadenitis have chronic non-specific mesenteric lymphadenitis.
If non-specific mesenteric lymphadenitis lasts more than 1 month, consider chronic mesenteric lymphadenitis. It is a common cause of recurrent abdominal pain in children.
Morbidity
It occurs throughout the year, with a high incidence in winter and spring.
It is more common in children and adolescents and less common in adults. There is no gender difference in incidence [3].
Causes
Causes
The exact etiology of the disease is unknown and is mostly thought to be due to viral infections, which may also be associated with bacterial infections or other pathogens.
Viral infection
Epidemiologic investigations suggest an association with viral infections, but strong clinical and experimental evidence is lacking.
Possible causative viruses are coxsackievirus B, echovirus, adenovirus, EBV, and microvirus B19.
Bacterial infections
Bacterial infections are rare.
Bacteria that may be associated with the disease include Streptococcus hemolyticus, Staphylococcus aureus, Salmonella, Yersinia pseudotuberculosis, and others [4].
Others.
In recent years, it has been found that Mycoplasma pneumoniae infection, amoeba protozoa, schistosomes and other parasites may also cause the disease.
Pathogenesis
After viruses, bacteria, mycoplasma, parasites and other human infections, the toxins can reach the mesenteric lymph, which is very rich in lymphatic drainage, and cause mesenteric lymphadenitis [1].
In children, the lymphatic system is immature, the barrier effect is weak, the end of the ileum and the ileocecal part of the mesenteric lymphatic drainage is very rich, coupled with the closure of the ileocecal valve, viruses, bacteria, mycoplasma, parasites and other pathogens or their toxins are easy to stay in the ileocecal part of the ileocecal part of the retention, absorption, causing mesenteric lymphatic non-specific inflammation.
Symptoms
Main Symptoms
Prodromal symptoms
Patients often have symptoms such as sore throat and tiredness and discomfort before the onset of the disease.
Typical symptoms
Fever
Fever can be present at the early stage of the disease, and the body temperature is usually 38.0°C to 38.5°C [5].
Abdominal pain
Lymph node congestion and edema, increase in size, pericardial tension, involving and causing acute abdominal pain, vomiting and other digestive symptoms, the nature of the pain varies, part of the change only mild discomfort, manifested as paroxysmal spasmodic abdominal pain, a small number of persistent severe colicky pain.
The site of pain is not fixed, can be changed with the position, mostly in the umbilicus, the right lower abdomen, can also appear in the whole abdominal distension, usually no obvious signs of peritoneal irritation.
It may be accompanied by gastrointestinal symptoms such as loss of appetite, nausea, vomiting, diarrhea, etc., and some of them may have constipation.
Complications
Purulent mesenteric lymphadenitis
Acute mesenteric lymphadenitis due to bacterial infection may develop into pyogenic mesenteric lymphadenitis if not treated in time.
Most of the patients have an acute onset and rapid progression, and may present with fever and obvious abdominal tenderness [1].
Consultation
Department of Medicine
General Surgery
Adults with fever, abdominal pain, vomiting, and diarrhea may consult the general surgery department.
Pediatrics
Children with symptoms such as fever, abdominal pain, vomiting and diarrhea can go to the Department of Pediatrics.
Emergency Department
Children with symptoms such as high fever (>39℃), severe abdominal pain, and confusion should go to the Emergency Department of the hospital or call “120” immediately.
Preparation for medical treatment
Preparing for medical treatment: registering, preparing documents, and common problems.
Tips for seeking medical treatment
When seeking medical treatment, it is recommended that you wear clothes that can be easily put on and taken off so that you can be examined accordingly.
Keep a detailed record of the symptoms you have experienced, as well as the time they occurred and how they have changed, so that the doctor can understand the progression of the disease.
Preparation Checklist
Symptom list
Pay particular attention to the time of onset of symptoms, special manifestations, etc.
When did the fever appear? What were the highest and lowest temperatures?
When did the abdominal pain occur? Was the abdominal pain severe? Is it paroxysmal or persistent?
Are there any stool abnormalities? Was there any diarrhea or constipation?
Was there any nausea or vomiting?
Medical History Checklist
Any symptoms of upper respiratory infection such as sore throat, runny nose, cough, etc. within two weeks?
Any recent viral enteritis or other intestinal illness?
Checklist
Test results in the last 6 months, which can be carried to the doctor
Laboratory Tests: Blood Tests
Imaging tests: abdominal ultrasonography, abdominal CT examination
Diagnosis
Diagnostic basis
Medical history
History of acute upper respiratory tract infection and intestinal infection, such as common cold, influenza, viral enteritis, etc.
Clinical manifestations
The main manifestations are fever, abdominal pain, nausea, vomiting, sometimes accompanied by diarrhea or constipation.
Physical signs
Facial flushing, pharyngeal congestion, enlarged tonsils, and cervical lymphadenopathy can be seen.
Abdominal tenderness is obvious on palpation, and the location of pain is not fixed, mostly in the right lower abdomen or around the umbilicus.
Abdominal muscle tension is mild or absent, often without obvious rebound pain.
Occasionally, a nodular mass with tenderness can be palpated in the right lower abdomen, which is likely to be an enlarged mesenteric lymph node.
Laboratory tests
Blood tests
The initial determination of whether there is an infection in the body is made.
The peripheral blood leukocyte count is often not elevated or instead decreases, while the lymphocyte ratio increases. c-reactive protein may be elevated [3].
It should be noted that it is not possible to determine whether the infection is bacterial or viral simply based on the routine blood test, but also needs to be combined with symptoms and signs.
Imaging
Abdominal ultrasound
Abdominal ultrasonography can clearly show the number of lymph nodes, whether they are adherent to the surrounding area, and their size, which can be used as the preferred examination method for this disease.
Abdominal ultrasonography can find large lymph nodes, and color Doppler ultrasonography shows colored blood flow signals in enlarged lymph nodes [6].
Abdominal CT examination
When ultrasonography is not definitive, abdominal CT may be considered.
Enlarged mesenteric lymph nodes are seen. However, due to its difficulty in finding the largest section of lymph nodes, and the disadvantages of high radiation and expensive cost, it is difficult to realize long-term follow-up, and its clinical utility is limited.
Differential diagnosis
Acute appendicitis
Similarities: both may present with fever, right lower abdominal pain and tenderness.
Differences: Most acute appendicitis has typical metastatic right lower abdominal pain, appendiceal pressure, and increased white blood cell count and neutrophil ratio. Ultrasound reveals an enlarged appendix or abscess. Nonspecific mesenteric lymphadenitis has a different presentation and ultrasound findings [7].
Intussusception
Similarities: Both may present with nausea, vomiting, and paroxysmal abdominal pain.
Differences: intussusception occurs in infants and young children, and the typical symptoms are paroxysmal abdominal cramps, jam-like blood stools, and abdominal masses; “concentric circles” or “target rings” can be seen in the transverse scanning of the site of abdominal ultrasound in patients with intussusception, while nonspecific mesenteric lymphadenitis has no such manifestations. Non-specific mesenteric lymphadenitis has no such manifestations.
Bowel spasm
Similarities: both present with abdominal pain.
Differences: intestinal cramps are often transient abdominal pain with diarrhea; ultrasonography reveals liquid dark areas in the intestinal canal with fair translucency and increased peristalsis, but fails to detect enlarged mesenteric lymph nodes.
Mesenteric lymph nodes
Similarity: both may present with nausea, vomiting, paroxysmal pain in the abdomen, and enlarged lymph nodes can be seen on ultrasound.
Differences: Acute tuberculous mesenteric lymph nodes are most common in adolescents, who may have primary foci of intestinal tuberculosis or pulmonary tuberculosis. Before the acute onset, patients are often accompanied by low-grade fever, night sweats, fatigue, intermittent abdominal pain in the umbilicus or right lower abdomen, and a history of diarrhea.
Malignant lymphoma
Similarity: both can present with fever and abdominal pain, and enlarged lymph nodes can be seen on ultrasound.
Differences: malignant lymphoma of mesenteric membrane may have recurrent fever and abdominal pain, abdominal mass, emaciation, and the enlarged lymph nodes tend to be rounded, with aspect ratio <2, and the involved segments are longer, often losing the morphology of normal lymph nodes, and there may be fusion, central necrosis, and punctate calcification, which is distinctly different from this disease.
Treatment
Aim of treatment: to relieve symptoms and avoid serious complications.
Treatment principle: internal conservative treatment, rest, symptomatic supportive therapy, etc., and surgery if necessary.
General treatment
Avoid pressing on the abdomen to prevent increasing the stimulation of lymph nodes and aggravating the symptoms.
Rest in bed and avoid over-exertion.
Patients with severe vomiting can be fed temporarily, and moderate fluid supplementation can be used to prevent dehydration.
Medication
Antipyretic drugs
Commonly used drugs include ibuprofen and acetaminophen.
They can reduce body temperature and relieve symptoms.
Anti-infective drugs
Applicable to patients with clear bacterial infection, commonly used drugs are penicillin, cefixime, roxithromycin and so on.
It should be noted that most patients with viral infections do not need to use antimicrobial drugs and are not effective in shortening the course of the disease [8].
Antispasmodic and analgesic treatment
Antispasmodic analgesics may be administered to patients with severe pain and a clear diagnosis.
Surgical treatment
Surgery should be performed if conservative treatment is ineffective, if the condition worsens, or if a combination of appendicitis or other acute abdominal conditions is considered.
In the case of purulent mesenteric lymphadenitis, abdominal drainage is often performed; when adjacent bowel is involved, resection of the affected bowel is necessary.
Prognosis
Cure
Non-specific mesenteric lymphadenitis is a self-limiting disease with a favorable prognosis.
Most patients improve at 3 to 4 days [2].
Hazards
Untreated acute mesenteric lymphadenitis due to bacterial infection may develop into septic mesenteric lymphadenitis, affecting disease recovery.
Symptoms such as fever, abdominal pain, nausea, and vomiting may affect normal life and sleep in severe cases.
Non-specific mesenteric lymphadenitis may be complicated by appendicitis, and failure to diagnose the disease in time may affect the subsequent treatment.
Daily routine
Daily Management
Dietary management
When vomiting is severe, food can be eaten temporarily to avoid aspiration.
Usually, small and frequent meals with mild and non-irritating food can be consumed.
Patients with severe diarrhea should pay attention to water intake to prevent dehydration.
Do not overeat to prevent increasing the burden on the gastrointestinal tract.
Life management
Keep the room temperature at 22~26℃ with suitable humidity to improve comfort.
Open the windows regularly every day to keep the indoor air fresh.
When fever sweats a lot, you should dry the sweat in time, change clothes and blankets to prevent getting cold.
Exercise is not recommended during the acute stage to prevent aggravation of symptoms. Choosing suitable exercise in the remission period is conducive to strengthening the body and restoring health [9-10].
Prevention
The etiology of non-specific mesenteric lymphadenitis has not been completely clarified, and there is no effective preventive measure, but the following ways can reduce the probability of this disease.
Try not to go to or go to less crowded areas in normal times, wear a good mask when going out, and wash your hands in a standardized way after coming back.
Try to avoid patients with infectious diseases such as colds and influenza, and those who must be in contact with them should be well protected.
Choose appropriate exercise methods to keep the body’s immunity normal.
During the use of medication, follow the doctor’s instructions to take medication on time and complete the course of treatment to avoid delayed recovery.
Pay attention to dietary hygiene to avoid contamination of food and drinking water.