尿道结核

　　1、发病原因

　　多因前列腺及精囊结核直接蔓延到后尿道，或因泌尿系结核、阴茎结核引起尿道感染。或者经盆腔以及腹膜结核直接蔓延导致，还可经肾结核直接蔓延到尿道。

　　2、发病机制

　　结核感染先于黏膜上形成结核结节，结节扩大互相融合形成溃疡，溃疡的基底由肉芽组织组成，肉芽组织纤维化引起狭窄梗阻。

　　尿道结核的并发症包括尿道狭窄梗阻，严重时尿道结核可向周围蔓延，导致尿道皮肤瘘或尿道直肠（阴道）瘘。上行感染可以导致膀胱结核、膀胱挛缩、输尿管结核、肾结核。经血液循环可以蔓延到全身各组织和器官，造成腹膜结核、肺结核以及骨结核。故出现尿道结核的患者应行B超、CT、MRI明确是否有合并其他部位的结核。

　　1、尿频，尿痛，尿道流血或血尿。

　　2、排尿困难，包括尿线变细，射程缩短，排尿无力。

　　3、会阴部扪及粗，硬，索条状的尿道或形成尿道瘘。

　　4、生殖系统检查，常可扪及前列腺，精囊，附睾尾有硬质结节，并可发现输精管有串珠样结节。

　　To prevent the occurrence of tuberculosis, the following points should be paid attention to:

　　1. Strengthen health education to make young people understand the harm and modes of transmission of tuberculosis. Develop good hygiene habits such as not spitting on the ground. The sputum of tuberculosis patients should be incinerated or disinfected with drugs.

　　2. Regular physical examinations should be conducted for adolescents to achieve early detection, isolation, and treatment. In addition, tuberculosis vaccine should be administered on schedule to infants and young children to produce immunity and reduce the incidence of tuberculosis.

　　3. If symptoms such as low fever, night sweats, dry cough, and blood streaks in sputum are found, it is necessary to go to the hospital for a check-up promptly. After the diagnosis of tuberculosis, treatment with streptomycin, rifampicin, and ethambutol should be initiated immediately. At the same time, attention should be paid to increase nutrition to enhance physical fitness. As long as it is detected early and treated thoroughly, tuberculosis can be completely cured.

　　4. Tuberculosis is a disease caused by Mycobacterium tuberculosis, transmitted through the respiratory tract, mainly through droplets emitted when coughing, sneezing, or speaking loudly. Therefore, to avoid infection, it is necessary to develop good hygiene habits. When sneezing, use a handkerchief to cover your mouth to avoid facing others; frequently ventilate the room, and be more vigilant in crowded places; also, exercise more to enhance immunity.

　　1. Urinalysis

　　About 90% of patients can be found with abnormal urine, which is generally acidic. Under the microscope, purulent urine and hematuria are the most common, accompanied by a small amount of urinary protein. Urinalysis is an important clue for early screening of renal tuberculosis.

　　2. Urine smear for tuberculosis bacteria

　　It is necessary to take a 24-hour urine or the first morning urine sediment for direct smear, perform acid-fast staining to find tuberculosis bacteria, and check for 3 times. 50% to 70% of patients can find tuberculosis bacteria. However, it should be noted that if the smear is positive, it cannot be completely determined, as smegma bacteria or other acid-fast bacilli can contaminate urine, which is difficult to distinguish from Mycobacterium tuberculosis morphologically, leading to false positives. Especially, one should not rely on a single positive result for diagnosis. Therefore, when collecting urine samples, the vulva and urethral orifice should be cleaned to avoid contamination, and all anti-tuberculosis drugs should be discontinued one week before the examination to increase the positive rate of urine testing.

　　3. Urine tuberculosis culture

　　It is an important basis for diagnosing renal tuberculosis and can be used for bacterial resistance monitoring. It is generally believed that morning urine samples are better than 24-hour urine, as morning urine is easier to collect and less likely to be contaminated. However, since the excretion of tuberculosis bacteria into urine is intermittent, at least 3 days of morning urine should be collected for tuberculosis culture before the use of anti-tuberculosis treatment, with a positive rate of 80% to 90%. Some scholars suggest collecting 6 times of morning urine cultures is better.

　　4. Immunological methods

　　Immunodiagnosis is based on the principle of specific reactions between antigens and antibodies, detecting antigens, antibodies, and antigen-antibody complexes in serum and urine, which helps in the diagnosis of tuberculosis. Common detection methods include radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA). Hubei Medical College used ELISA to measure the tuberculosis antibody for the diagnosis of renal tuberculosis, with a coincidence rate of 82% with pathological diagnosis. If both antigens and antibodies are measured, the positive rate can reach 96.5%, close to that of tuberculosis culture.

　　5. Urethrogram:It can show the location, length, and whether it is multiple strictures of the urethral stricture.

　　6. Urethral biopsy, histological examination can be diagnosed

　　1. Foods that are good for urethral tuberculosis patients

　　Drink plenty of water and eat more coarse grains and vegetarian foods.

　　2. Foods to avoid for urethral tuberculosis

　　It should be avoided to eat foods high in oxalic acid, such as spinach, mushrooms, potatoes, chestnuts, strong black tea, coffee, chocolate, tomatoes, strawberries, persimmons, myrica rubra, etc. If it is a patient with uric acid stones, it should be noted to eat as little as possible foods high in uric acid, such as animal internal organs, seafood, strong black tea, coffee, chocolate, and peanuts. Patients with calcium phosphate stones should eat less food rich in calcium, such as milk.

　　1. Treatment

　　Urethral tuberculosis is part of the urogenital tuberculosis, so the kidney tuberculosis, prostatic tuberculosis, epididymis tuberculosis should be treated first. The stricture caused by urethral tuberculosis was previously treated with urethral dilation, but urethral dilation can cause septicemia, tuberculosis dissemination, so it should be treated first with medication, and then urethral dilation after tuberculosis is cured, but the effect of urethral dilation is not ideal, often after dilation and then recover to the original state, and need to be regularly dilated multiple times to have a certain effect. Patients with urethral tuberculosis that have caused obstruction and cannot be dilated or have poor dilation effect can be treated first with bladder fistula, but there is a high chance of developing a contracted bladder.

　　If the stricture is localized, surgical treatment can be performed to excise the stricture scar and anastomose the opposite ends or perform an internal urethrotomy under urethroscope vision. For longer strictures, the scrotal flap inlay method (Scrotal flap inlay) can be used for repair (Symes, 1973). If the bladder lesion is severe, bladder contracture, contralateral hydronephrosis, then it should be done first nephrostomy drainage, wait until the urethral tuberculosis cured and then dealt with. Difficulties in treatment sometimes require urinary diversion surgery, at this time, it also needs to be noted that the bladder with urethral obstruction is prone to abscess often need to be resected.

　　2. Prognosis

　　Urethral tuberculosis often occurs secondary to severe urogenital tuberculosis, which is difficult to treat. If the urogenital tuberculosis can be recovered and the range of urethral stricture is small, the prognosis is better.