There is no early sign of pyelonephritis. Early symptoms of bladder involvement include frequent urination, urgency, and painful urination, and early manifestations of most patients include fever and back pain. Chronic pyelonephritis may have no special symptoms or only discomfort in the lower back. Pyelonephritis belongs to the upper urinary tract infection, which is divided into acute and chronic, acute pyelonephritis and chronic pyelonephritis acute attack, most patients will be early manifested as frequent urination, urinary urgency, urinary pain and other symptoms of bladder irritation, if this time, if you do not take active treatment of the infection will be on the rise, which will lead to pyelonephritis. However, some patients, especially those with low immunity, may not have symptoms such as frequent urination, urgent urination, painful urination, etc., and may even have no symptoms at the early stage of the disease, which can only be detected through relevant examinations. As chronic pyelonephritis often has no obvious discomfort in the early stage, it is not possible to judge whether it is pyelonephritis based on the presence or absence of symptoms, and it is necessary to consult a doctor for urine routine, blood routine, urine culture and other related examinations to confirm the diagnosis. If the above symptoms occur, it is recommended to consult a doctor in time to clarify the condition, and actively treat the disease under the guidance of the doctor.