Common symptoms of undifferentiated spondyloarthritis include back pain, lower extremity pain, swelling of fingers and toes, unilateral eye pain, and diarrhea. 1. Back pain: the most common symptom of the disease is back pain, there are five criteria, four of which are inflammatory back pain, age greater than 40 years old; insidious onset of the disease; improvement after exercise; pain at night; and rest can not be improved. 2. Lower limb pain: manifested as swelling and pressure pain in the knee joint. 3. Swelling of fingers and toes: diffuse swelling of fingers and toes, caused by swelling of tendon sheaths and surrounding soft tissues. 4. unilateral eye pain: unilateral eye redness, eye pain, fear of light, with transient conjunctivitis, which may resolve on its own. 5. Diarrhea: there are symptoms of diarrhea and vomiting, most patients have inflammation of the intestinal mucosa, and the inflammation is parallel to the arthritic condition. If the above related symptoms occur, it is recommended to consult the doctor and standardize the treatment in time.