Renal tuberculosis is easily misdiagnosed, so how should it be detected early? This requires an analysis of the causes of misdiagnosis. The main reason for misdiagnosis of renal tuberculosis is that its clinical manifestations resemble urinary tract infections, especially chronic lower urinary tract infections, while its symptoms of tuberculosis toxicity are rare. In fact, the so-called “chronic cystitis” can be seen in a variety of diseases, such as non-specific urinary tract infections, bladder stones (more pronounced in those with secondary infections), lower urinary tract obstruction secondary to infection, tumors in the bladder triangle or with ulcerative necrosis and renal tuberculosis, etc. Therefore, “chronic cystitis” should be considered as a clinical symptom and its causes should be further investigated. In our country, the most common disease causing chronic cystitis is renal tuberculosis. Although the symptoms of renal tuberculosis are similar to those of many diseases, careful analysis reveals that renal tuberculosis has its own characteristics. We call it “early clues symptoms”. These include: (1) “cystitis” that cannot be cured in a short period of time, recurring and progressively worsening, which should be considered as a preliminary diagnosis of renal tuberculosis, especially if it is accompanied by terminal hematuria, or in young men. In addition, painless hematuria is a clinical characteristic of urological tumors, but its age of onset is high. For painless hematuria under 40 years old, renal tuberculosis should be taken into consideration. If the urine is acidic, with a small amount of protein, red blood cells and white blood cells, it may be the earliest change of renal tuberculosis, and tubercle bacilli can be found in the urine at this time. If the symptoms of “cystitis” are present and the above-mentioned abnormalities in the urine routine are seen, the diagnosis of this disease should be considered. (3) If there are pus cells and acidic urine test, but there is no bacterial growth in common culture, the possibility of tuberculosis is high. However, 20-60% of renal tuberculosis can have mixed infections, so as long as the features of chronic tuberculous cystitis mentioned above are present, even if common bacteria are cultured, renal tuberculosis should be suspected; 90% of the mixed infections are E. coli, so repeated E. coli infections should be checked for urinary tuberculosis bacteria. ④ Male patients with tuberculosis lesions in the genitalia. It is often an important clue for early detection of renal tuberculosis. Therefore, external genital examination and rectal examination should be routinely performed in male patients. Although the above-mentioned symptoms provide clues of renal tuberculosis, laboratory tests and imaging examinations are needed to further confirm the diagnosis. (1) Laboratory tests: urine routine, urine sediment smear for antacid bacilli, urine tuberculosis culture, and PCR for mycobacterium tuberculosis. (2) Imaging examinations: chest X-ray, abdominal plain film, intravenous urography, cystoscopy and retrograde urography and CT examination. This will determine the location, extent, and degree of destruction of the lesion, as well as whether the contralateral kidney is normal and the degree of bladder destruction; in addition, the general health status and whether other organs are combined with tuberculosis should also be understood.