Diagnostic criteria There are no uniform diagnostic criteria for UCTD. The names of UCTD and its diagnostic conditions are listed in Table 3 for clinical and research reference. According to foreign reports and analysis of 70 patients with UCTD at the People’s Hospital of Peking University, the diagnosis of UCTD should have more than one typical symptom or sign of rheumatic disease with more than one high-titer autoantibody positivity, a disease duration of more than two years, and exclude any other CTD. Analysis of limited cases from abroad and our hospital suggests that those who meet the clinical features of UCTD health search, but have a short disease duration may It is not uncommon for patients with Raynaud’s phenomenon with positive ANA to develop typical SLE or scleroderma within one or two years, or even several years after the diagnosis of UCTD, within a certain period of time, with typical clinical manifestations of other CTDs or laboratory abnormalities. Therefore, the disease should not be easily diagnosed in patients with a disease duration of less than two years. Even in cases of longer duration with a clear diagnosis, close follow-up should be performed to note the possibility of developing other CTDs. In patients with diffuse CTD disease who have been treated with immunosuppressive drugs and glucocorticoids earlier, the disease may be partially controlled and may not show the clinical manifestations and laboratory abnormalities of other CTDs, thus qualifying for the diagnosis of UCTD. This “setback” after treatment is itself a reflection of effective treatment, but it is also easy to neglect further examination and formal treatment of the patient’s health search. Therefore, more systematic laboratory tests should still be performed on such patients, such as muscle biopsy for suspected dermatomyositis, and anti-nuclear antibody and anti-ds-DNA antibody tests for suspected SLE, in order to make a correct diagnosis and provide timely and regular treatment. Clinically, care should be taken to distinguish undifferentiated connective tissue disease from overlap syndrome and mixed connective tissue disease (MCTD). Overlap syndrome refers to the simultaneous or sequential appearance of clinical manifestations of two connective tissue diseases that meet the respective diagnostic criteria. Mixed connective tissue disease has internationally accepted diagnostic criteria and may have clinical symptoms similar to those of SLE, polymyositis or progressive systemic sclerosis, but does not meet their diagnostic criteria and is characterized by Raynaud’s phenomenon, swelling hand lung involvement and high titers of nRNP antibodies. Laboratory tests Patients with UCTD may present with a variety of abnormal laboratory tests. However, for each individual, most patients with UCTD have only one or two laboratory abnormalities with a relatively homogeneous autoantibody profile. Blood tests may show leukopenia, thrombocytopenia, or anemia. Those with hemolytic anemia may have a prolonged partial thromboplastin time in patients with positive Coombs test autoimmune thrombocytopenia. Urinary routine may show proteinuria and hematuria. Accelerated hematocrit and elevated gamma-globulin may be seen Some patients show elevated transaminases, often suggesting autoimmune liver damage. ANA positivity is most common in serological examination, with a positive rate of 55% to 100%, averaging 58%. The fluorescent karyotype is most common with the spotted type, while the homogeneous and perinuclear types are less common, and the titer is similar to that of SLE. A small number of patients may have positive anti-RNP antibodies, anti-SSA or SSB antibodies to rheumatoid factors. The presence of anti-RNP antibodies is often associated with Raynaud’s phenomenon and arthritis, while those with positive anti-SSA antibodies are often associated with dry mouth health search positive anti-dsDNA antibodies, positive anti-Sm antibodies false positive syphilis serologic tests and reduced complement are rare. Other ancillary tests: For other ancillary tests, ultrasound may reveal enlarged liver and spleen lymph nodes, and ultrasound and x-ray may also reveal pericardial or pleural effusion. Abnormal lung function is rare. Related tests: >Coombs test >coagulation time measurement >anti-RNP antibody >anti-Sm antibody >anti-nuclear antibody >lupus cells >rheumatoid factor >deoxyribonucleic acid staining >Sudan black B staining >platelets >partial thromboplastin time Treatment Patients with UCTD often have mild clinical manifestations and are generally treated symptomatically. The aim of treatment is to alleviate the clinical symptoms of patients, to bring about long-term remission and to prevent adverse regression treatment protocols and drug doses should pay attention to the principle of individualization, and to observe the adverse effects of drugs. 1. Symptomatic treatment of weakness, fever, arthralgia or arthritis can be used for non-steroidal anti-inflammatory drug treatment. Individual differences in the efficacy of NSAIDs are large Generally speaking, those with severe symptoms prefer diclofenac and other anti-inflammatory drugs with better effects; those with mild symptoms or long-term medication can choose slow-release NSAIDs with small adverse effects and convenient administration, such as meloxicam and nabumetone; those with a history of upper gastrointestinal tract inflammation and ulcers should choose selective COX-2 inhibitors such as rofecoxib and celecoxib. Patients with Raynaud’s phenomenon should be kept warm and treated with vasodilators such as calcium channel antagonists depending on the extent of the disease. In patients with severe symptoms or ulcers on the extremities, intravenous prostaglandins and regia can be given to improve circulation. Patients with photosensitivity should pay attention to avoid direct sunlight. Adrenocorticosteroid facial rash can be applied topically with hormonal ointment. Arthritis that is difficult to relieve can also be treated with local injections of betamethasone (Depo-Provera) and deferiprone acetate in the joint cavity. Systemic hormone therapy can be applied in cases with organ involvement such as pericarditis, thrombocytopenia or hemolytic anemia, but high doses of hormones should not be used. Except for special cases, generally prednisone 0.5mg/(kg?d) can make the condition improve, and then it should be reduced to a small dose of less than 10mg/d as soon as possible to reduce the occurrence of hormone adverse reactions. A survey by the European League Against Rheumatism found that 38% of patients were treated with oral prednisone after initial diagnosis, but the amount of hormone was ≤10 mg/d, and the proportions were 43% and 27% at the 1-year and 2-year follow-ups, respectively. In 1989, Jonathan et al. summarized the clinical data of 38 patients and found that 47% (18/38) required only NSAIDs, 11% (4/38) were treated with topical hormones, 32% (12/38) were treated with oral hormones, 29% (11/38) were treated with hydroxychloroquine or chloroquine, and only one case (3%) was treated with immunosuppressive drugs. Only one case (3%) required immunosuppressive therapy. Except for one patient with autoimmune thrombocytopenia, the dose of oral hormone was mostly 20 mg/d or less and could be reduced quickly. 3. Immunosuppressants can also be tried in patients for whom conventional treatment is ineffective, for whom clinical treatment experience is less reported health search. Generally, different regimens are given according to the clinical symptoms with reference to the treatment of other connective tissue diseases. However, small doses and short courses of treatment are recommended. Commonly used immunosuppressive agents include methotrexate and azathioprine. In 1995, Wise et al. reported that methotrexate could be tried in patients with polyarthritis and difficulty in hormone reduction at doses similar to those used in systemic lupus erythematosus. Fifty-three percent of the patients treated showed the most significant improvement in polyarthritis and skin mucosal lesions. 60% of the patients experienced adverse effects, and 33% of them had to discontinue treatment. One patient in the 25 mg/week dose group developed an opportunistic pathogenic infection, cryptococcal encephalitis, and was treated with prednisone 30 mg/d Health Search. Overall, the safety of methotrexate treatment is fair with attention to lower doses and the ability to follow closely during treatment. In addition, in patients with refractory UCTD, immunosuppressants such as leflunomide cyclosporine A may be effective but more clinical studies are needed to confirm this. 4. Antimalarial drugs can be tried for patients with fever, facial rash and arthritis, and can be used in combination with NSAIDs. The usual dose of hydroxychloroquine is 200-400 mg/d. At this dose, damage to the fundus rarely occurs. However, as a precaution, an ophthalmologic examination should be performed before and every 3-6 months after the administration of the drug to note changes in the visual field and the occurrence of lesions such as fundus. A survey conducted by the European League Against Rheumatism in 2000 found that about 17% of 112 patients with UCTD were treated with antimalarials, but the proportion rose to about 32% after 2 years. This result suggests that patients have good compliance with antimalarial treatment for health search, and the incidence of discontinuation due to adverse effects is low enough for long-term use. Prognosis prevention Studies have shown that the incidence of visceral involvement such as interstitial lung fibrosis, renal damage and central nervous system damage in this disease is low, and the prognosis is relatively good with more than half of the patients in complete remission at long-term follow-up. 1. Remove the triggers of the disease, pay attention to hygiene and strengthen physical exercise to improve their immunity and prevent infection. 2. Early diagnosis and treatment, do not give up treatment easily when the disease is in remission.