Lymphadenitis

Lymphadenitis is inflammation of one or more lymph nodes, which usuallybecome swollen and tender.

Lymphadenitis is almost always caused by an infection, which may be due tobacteria, viruses, protozoa, rickettsiae, or fungi. Typically, the infectionspreads to a lymph node from a skin, ear, nose, or eye infection or fromsuch infections as infectious mononucleosis, cytomegalovirus infection,streptococcal infection, tuberculosis, or syphilis.

The infection may affectmany lymph nodes or only those in one area of the body.

Symptoms and DiagnosisInfected lymph nodes enlarge and are usually tender and painful. Sometimes,the skin over the infected nodes looks red and feels warm. Occasionally,pockets of pus (abscesses) develop. Enlarged lymph nodes that do not producepain, tenderness, or redness may indicate a serious disorder, such aslymphoma, tuberculosis, or Hodgkin's disease.

Such lymph nodes require adoctor's attention. Usually, lymphadenitis can be diagnosed on the basis of symptoms, and itscause is an obvious nearby infection. When the cause cannot be identifiedeasily, a biopsy (removal and examination of a tissue sample under amicroscope) and culture may be needed to confirm the diagnosis and toidentify the organism causing the infection.

Treatment and PrognosisTreatment depends on the organism causing the infection. For a bacterialinfection, an antibiotic is usually given intravenously or orally.

Warmcompresses may help relieve the pain in inflamed lymph nodes. Usually, oncethe infection has been treated, the lymph nodes slowly shrink, and the painsubsides. Sometimes the enlarged nodes remain firm but no longer feeltender. Abscesses must be drained surgically. (Merck)