What is lymphadenitis (inflammation of the lymph nodes)?

From the Guidelines

Lymphadenitis is an inflammation of the lymph nodes, typically caused by infection from bacteria, viruses, or other pathogens, and is diagnosed based on histopathologic appearance and culture of the lymph node, as seen in studies such as 1. This condition can manifest as swollen, tender, and painful lymph nodes, often accompanied by redness, warmth, and sometimes fever, fatigue, and general malaise. The lymph nodes, small bean-shaped structures, play a crucial role in the immune system, and their inflammation can be acute or chronic.

• Common symptoms of lymphadenitis include:
  • Swollen and tender lymph nodes
  • Redness of the skin over the affected nodes
  • Warmth in the area
  • Fever
  • Fatigue
  • General malaise
• The diagnosis of lymphadenitis, particularly in cases of nontuberculous mycobacterial (NTM) diseases, relies on the histopathologic appearance of the lymph node, showing caseating granulomata with or without acid-fast bacilli (AFB), and a negative tuberculin skin test, as noted in 1.
• A definitive diagnosis is made by recovering the causative organism from lymph node cultures, which may involve fine needle aspiration biopsy, incision and drainage, or excisional biopsy, although the latter carries a risk of injury to the facial nerve, especially with preauricular lymph nodes, as cautioned in 1.
• Treatment of lymphadenitis depends on the underlying cause, and while specific antibiotic regimens are not detailed in 1 for lymphadenitis broadly, the principle of targeted therapy based on the causative pathogen is crucial.
• It is essential to seek medical attention for persistent or severe lymph node swelling, as it could indicate a serious underlying condition requiring specific treatment, highlighting the importance of prompt diagnosis and appropriate management to prevent complications and improve outcomes.

From the Research

Definition and Causes of Lymphadenitis

• Lymphadenitis refers to the inflammation of the lymph nodes, which can be caused by various factors, including infections, autoimmune disorders, and malignancies 2, 3, 4, 5, 6.
• The most common causes of lymphadenitis in children are infections, with bacterial, viral, and mycobacterial infections being the most frequent 2, 3, 4, 5.
• Specific causes of lymphadenitis include mycobacterial infection, Staphylococcus aureus, and other bacterial and viral infections 2, 3, 6.

Clinical Presentation and Diagnosis

• Lymphadenitis can present with symptoms such as enlarged lymph nodes, pain, and swelling, and can be diagnosed through clinical examination, laboratory tests, and imaging studies 3, 5.
• The diagnosis of lymphadenitis can be challenging, and a thorough diagnostic process is necessary to determine the underlying cause 2, 3, 4, 5, 6.
• Laboratory tests, such as histological examination, culture, and polymerase chain reaction (PCR), can be used to identify the causative agent of lymphadenitis 6.

Management and Treatment

• The management of lymphadenitis depends on the underlying cause and can include surgical treatment, medical care, and observation 2, 4, 5.
• In some cases, complete surgical excision of the lymph node may be necessary for definitive healing, especially in cases of mycobacterial lymphadenitis 2.
• Antibiotic therapy may be indicated in cases of bacterial lymphadenitis, and empiric antibiotic therapy may be considered in certain situations 5.