The presence of back pain followed by fever is likely to be a sign of acute pyelonephritis, which is often caused by inflammation of the upper urinary tract due to retrograde infection by bacteria and other pathogenic microorganisms as a result of reduced resistance. Generally, the diagnosis of pyelonephritis can be clarified through urine routine, blood routine and urine culture, and some sensitive antibiotics such as levofloxacin tablets, ciprofloxacin tablets, cefuroxime tablets, azithromycin tablets and furantoin tablets can be selected for at least two weeks of continuous treatment to clear the pathogenic microorganisms in the urinary system so that pyelonephritis can be effectively controlled. At the same time, you can take some oral Chinese medicines to clear heat and dampness and promote diuresis, such as Sanjin Tablet, Hot Lin Qing Capsule and Bazheng Capsule, which are very helpful for the recovery of pyelonephritis. During the treatment period, you should avoid spicy and stimulating diet, do not drink alcohol and drink more water.