Urinary tuberculosis occurs when Mycobacterium tuberculosis spreads to the kidneys or other parts of the genitourinary system, often via the bloodstream (hematogenous spread) from an active or latent TB infection in the lungs or other organs. In some cases, the infection may also directly affect the urinary tract through direct extension from the kidneys or nearby structures.
• Hematogenous Spread: The bacteria can enter the bloodstream and travel to the kidneys, causing infection there.
• Reactivation: In individuals with a history of pulmonary TB, the infection can reactivate and spread to the urinary tract, particularly if the immune system becomes weakened.
Although it can affect both men and women, urinary tuberculosis is more commonly seen in men, particularly those between 20 and 50 years old.
The symptoms of UTB can be nonspecific and may mimic those of other urinary tract infections or kidney diseases, making diagnosis challenging. Common symptoms include:
1. Painful urination (dysuria): A burning sensation or discomfort during urination.
2. Frequent urination: The need to urinate more often than usual, particularly at night.
3. Hematuria (blood in the urine): Blood may be visible in the urine, especially in advanced stages.
4. Low back pain or flank pain: Pain in the lower abdomen or back, particularly in the region of the kidneys.
5. Urinary retention: Difficulty fully emptying the bladder.
6. Pyuria: Presence of pus or white blood cells in the urine, which may be a sign of infection.
7. Fever and malaise: Systemic symptoms such as low-grade fever, fatigue, and weight loss, which are often seen in tuberculosis infections.
8. Incontinence: Difficulty controlling urination, in some cases.
In advanced cases, the infection may result in kidney failure, scarring, and other severe complications.
Diagnosing urinary tuberculosis requires a combination of clinical evaluation, urine tests, imaging, and sometimes biopsy. Key diagnostic steps include:
1. Urine Tests:
o Urine acid-fast bacilli (AFB) smear: This test looks for the presence of Mycobacterium tuberculosis bacteria in urine. However, the sensitivity is not always high in UTB, especially in early stages.
o Urine culture: Culturing urine to grow M. tuberculosis is the gold standard for diagnosis but can take weeks to return results.
o Polymerase chain reaction (PCR): This test detects M. tuberculosis DNA and can provide a quicker diagnosis than traditional cultures.
2. Imaging:
o Ultrasound: Helps detect kidney abnormalities, such as scarring or abscesses.
o CT scan: More detailed imaging may reveal damage to the kidneys, bladder, and surrounding structures.
o X-rays: May be used to detect calcification or other signs of TB-related damage in the urinary tract.
3. Cystoscopy: A procedure where a camera is inserted into the bladder to examine the bladder lining and detect any lesions, strictures, or other abnormalities.
4. Biopsy: In cases where the diagnosis is unclear, a biopsy of affected tissue (e.g., kidney or bladder) may be necessary to confirm the presence of tuberculosis.
5. Mantoux Tuberculin Skin Test (TST) or Interferon-Gamma Release Assays (IGRAs): These tests may be helpful in assessing if there is any prior exposure to tuberculosis, though they are not specific to urinary TB.
The treatment of UTB is similar to the treatment of pulmonary TB, and it typically involves a combination of anti-tuberculosis medications. The goal is to completely eliminate the infection and prevent complications.
1. First-Line Anti-Tuberculosis Medications:
o Isoniazid (INH): Inhibits the growth of M. tuberculosis.
o Rifampicin (RIF): Another first-line antibiotic that is effective against M. tuberculosis.
o Pyrazinamide (PZA): Works to kill M. tuberculosis bacteria in acidic environments.
o Ethambutol (EMB): Used to inhibit the growth of the bacteria.
These drugs are typically used in combination for at least 6–9 months to ensure the complete eradication of the bacteria.
2. Second-Line Drugs:
o If the tuberculosis is resistant to the first-line medications (e.g., multidrug-resistant TB or MDR-TB), second-line drugs may be required, which can include:
Fluoroquinolones (e.g., levofloxacin or moxifloxacin).
Injectable agents (e.g., amikacin or kanamycin).
3. Surgery:
o In advanced cases where there is significant kidney or bladder damage (e.g., abscesses, fistulas, or scarring), surgery may be required. This could involve draining abscesses, removing affected kidney tissue, or other procedures to manage complications.
4. Management of Complications:
o If kidney function is compromised, dialysis may be necessary in severe cases.
o Pain management and supportive care are also important parts of treatment.
5. Monitoring:
o Regular follow-up with urine cultures and clinical assessments are necessary to monitor the effectiveness of the treatment and detect any possible relapse or drug resistance.
