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Lymphadenitis is swelling in the lymph nodes. It usually presents as one or more enlarged or swollen lymph nodes under the neck, in the armpits, or in the groin. Lymphadenitis is relatively common, and most often indicates presence of bacterial or viral infection. Fungal and parasitic infection can also result in lymphadenitis. Very occasionally, a lymph node may also be swollen as a result of cancerous cells invading the node. This is less common but may be tested if all other symptoms are ruled out.
The most common symptoms of lymphadenitis are swelling of one or more lymph nodes. Lymph nodes that are swollen may feel slightly hardened, and may be painful when touched. The skin covering the lymph node can sometimes feel hot to the touch or may appear slightly red.
A swollen lymph node usually means a doctor will want to look for the cause, especially if lymphadenitis is painful. Physicians may perform blood tests to screen for infections, and in some cases, may perform a small biopsy of the lymph node. If the suspected cause of lymphadenitis is viral, biopsy is rarely performed. Usually, lymphadenitis only indicates need for a biopsy if cancer is suspected.
Sometimes in children, chronic inflammation of one lymph node occurs and is not associated with discomfort, or heat or redness of the skin. This is actually not uncommon, and unless discomfort is present, doctors usually diagnose this as viral and do not treat it. Recent studies into the disease cat scratch fever do suggest it may be responsible for most incidences of chronic lymphadenitis in children. Since bacteria cause cat scratch fever, antibiotics can resolve the lymphadenitis.
Normal treatment for lymphadenitis of bacterial origin is a course of antibiotics. In all cases, physicians treat underlying causes when possible. You can also relieve minor discomfort from swollen lymph nodes by taking anti-inflammatory medications like ibuprofen.
A more serious form of lymphadenitis is lymphangitis, which almost always indicates the presence of bacterial infection. Its symptoms include high fever, red streaks around the swollen lymph node, throbbing pain in the lymph nodes, and flulike symptoms like lack of appetite, fatigue, and aching muscles. Lymphangitis is most associated with strep and staph bacterial infections. Cellulitis, infection of the blood, is a quite common cause. Since lymphangitis is often bacterial, a physician should promptly assess these symptoms.
Even with antibiotic treatment, it can take several months for lymph nodes to return to normal. Some people exhibit almost constant symptoms of lymphadenitis, which do not resolve, despite treatment. This can be especially true of people with compromised immune systems. Those with autoimmune disorders or with HIV are likely to experience chronic lymphadenitis. Some children, because of constant exposure to viruses,