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Chronic Lyme disease is a controversial diagnosis that encompasses post–Lyme disease syndrome, as well as "a broad array of illnesses or symptom complexes for which there is no reproducible or convincing scientific evidence of any relationship to ''B. burgdorferi'' infection."〔 There is no clinical evidence that "chronic" lyme disease is caused by a persistent infection. Most medical authorities advise against long-term antibiotic treatment for Lyme disease.〔〔〔 == Background == The Centers for Disease Control and Prevention state that "approximately 10 to 20% of patients treated for Lyme disease with a recommended 2–4 week course of antibiotics will have lingering symptoms of fatigue, pain, or joint and muscle aches. In some cases, these can last for more than 6 months. Although often called 'chronic Lyme disease', this condition is properly known as 'post-treatment Lyme disease syndrome' (PTLDS)". The term is often applied to several different sets of patients. One usage refers to people suffering from the symptoms of untreated and disseminated late-stage Lyme disease: arthritis, peripheral neuropathy and/or encephalomyelitis. The term is also applied to people who have had the disease in the past and some symptoms remain after antibiotic treatment, which is also called post-Lyme disease syndrome. A third and controversial use of the term applies to patients with nonspecific symptoms, such as fatigue, who show no objective evidence they have been infected with Lyme disease in the past, since the standard diagnostic tests for infection are negative. Up to one third of Lyme disease patients who have completed a course of antibiotic treatment continue to have symptoms, often termed "post-Lyme syndrome", such as severe fatigue, sleep disturbance, unconsciousness, and cognitive difficulties, with these symptoms being severe in about 2% of cases. While it is undisputed these patients can have severe symptoms, the cause and appropriate treatment is controversial. The symptoms may represent "for all intents and purposes" fibromyalgia or chronic fatigue syndrome. A few doctors attribute these symptoms to persistent infection with ''Borrelia'', or coinfections with other tick-borne pathogens, such as ''Ehrlichia'' and ''Babesia''.〔 Other doctors believe that the initial infection may cause an autoimmune reaction that continues to cause serious symptoms even after the bacteria have been eliminated by antibiotics. A review looked at several animal studies that found persistence of live but disabled spirochetes following treatment of ''B. burgdorferi'' infection with antibiotics. The authors noted that none of the lingering spirochetes were associated with inflamed tissues and criticized the studies for not considering adequately the different pharmacodynamics and pharmacokinetics of the antibiotics used to treat the animals in the trials versus what would be expected to be used to treat humans. The authors concluded, "There is no scientific evidence to support the hypothesis that such spirochetes, should they exist in humans, are the cause of post-Lyme disease syndrome." An advocacy group called the International Lyme And Associated Diseases Society (ILADS) argues the persistence of ''B. burgdorferi'' may be responsible for manifestations of late Lyme disease symptoms. It has questioned the generalizability and reliability of some of the above trials and the reliability of the current diagnostic tests.〔〔(【引用サイトリンク】title=EP&I | Full text | Generalizability in two clinical trials of Lyme disease )〕 Major US medical authorities, including the Infectious Diseases Society of America, the American Academy of Neurology, and the National Institutes of Health, have stated there is no convincing evidence that ''Borrelia'' is involved in the various symptoms classed as chronic Lyme disease, and advise against long-term antibiotic treatment as ineffective and possibly harmful.〔〔 Prolonged antibiotic therapy presents significant risks and can have dangerous side effects. One death has been reported from an infected catheter as a complication of a 27-month course of intravenous antibiotics for an unsubstantiated diagnosis of chronic Lyme disease. Randomized placebo-controlled studies have shown that antibiotics offer no sustained benefit in "chronic Lyme" patients, a review notes evidence of both placebo effects and significant adverse effects from such treatment. Antibiotic treatment is the central pillar in the management of Lyme disease. However, in the late stages of borreliosis, symptoms may persist despite extensive and repeated antibiotic treatment. Although these chronic symptoms are possibly due to either autoimmunity or residual bacteria (see immunological studies below), no ''Borrelia'' DNA can usually be detected in the joints after antibiotic treatment, which suggests the arthritis may continue, even after the bacteria have been killed.〔 Lyme arthritis that persists after antibiotic treatment may be treated with hydroxychloroquine or methotrexate. Corticosteroid injections into the affected joint are not recommended for any stage of Lyme arthritis. Patients with chronic neuropathic pain responded well to gabapentin monotherapy with residual pain after intravenous ceftriaxone treatment in a pilot study. Some antibiotics may have a dual effect on Lyme disease, since minocycline and doxycycline have anti-inflammatory effects in addition to their antibiotic actions, including anti-inflammatory effects specific to the inflammation caused by Lyme disease. Indeed, minocycline has been suggested for other neurodegenerative and inflammatory disorders, such as multiple sclerosis, Parkinson's disease, Huntington's disease, rheumatoid arthritis and ALS. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lyme disease controversy」の詳細全文を読む スポンサード リンク
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