A form of additional tuberculosis that affects the kidney is renal tuberculosis (renal TB), sometimes known as tuberculosis of the kidney. When TB affects an organ other than the lungs, it is referred to as extra-pulmonary tuberculosis. The pleura (the covering of the lungs), the tubes that carry the bone marrow, the hindbrain, the fallopian tube for females, and the epididymis in men are other locations of extra-pulmonary TB.

Either or both kidneys may be affected by renal tuberculosis. Although the infection often begins in the outside, or cortex, region of the kidney, the medulla, which is located inside, is typically the area that is afflicted. Sometimes the TB that permeates the general genitourinary tract includes renal tuberculosis. About 15 to 20% of all instances of extra-pulmonary TB are caused by genitourinary tuberculosis

Why Does Renal Tuberculosis Occur?

Mycobacterium tuberculosis, which would be a frequent cause of respiratory infections, particularly in the poor socioeconomic areas of the undeveloped and developing nations, is the cause of renal TB. Mycobacterium bovis and other forms may potentially be to blame.

The transfer of infection from those other bodily organs, particularly the lungs, through the blood can cause the kidneys to become infected. Anywhere between five and twenty years after a lung infection, kidney infection can happen. Secondary TB is the name given to this sort of kidney infection that develops from other locations in the body which are already compromised.

What are Renal Tuberculosis’s Symptoms and Signs?

Some kidney TB patients may not exhibit any symptoms. Clinical traits might consist of the following:

• checking for the presence of protein or pus in the urine
• Testing urine for germs revealed none
• blood present in the pee
• not responding to antibiotics
• decreased kidney performance
• When the lower urinary tract is also affected, increased urination frequency, burning when urinating, and frequent nighttime awakenings for urination
• There may also be signs of pulmonary TB, such as fever, sweating at night, and a productive cough.

What are Renal Tuberculosis’ Risks and Complications?

The following are some risks and complications associated with renal tuberculosis:

• Calcium buildup in the kidneys is a sign of gradually declining renal function.
• Hypertension
• keratinizing squamous metaplasia, a cellular alteration that increases the risk of squamous cell carcinoma, is developing.
• spreading kidney-circumferential abscess
• The ureters, the channels that convey urine from kidneys to the urinary bladder, are affected by TB. The infection may cause the tube to become ulcerated and narrow, which would stop urine from entering the bladder.
• Infection of the bladder with TB. The bladder can shrink and constrict, a condition known as thimble bladder. However, in men, the epididymis is where the TB infection most frequently spreads from, or when the BCG vaccination is injected into, the bladder.
• Termed hydronephrosis, kidney enlargement
• Advanced renal failure

How is Renal Tuberculosis Diagnosed?

Since few doctors will suspect the ailment, renal TB might be difficult to diagnose. However, since the patient might fully recover with the appropriate therapy, it is crucial to diagnose it.

The following tests are used to identify kidney tuberculosis:

A blood test

The following blood tests should be conducted:

A complete blood count and an ESR (erythrocyte sedimentation rate), which can show whether an infection is present. After commencing therapy, the ESR must be performed again on a weekly basis to assess the treatment’s effectiveness.

Kidney function tests, that evaluate blood urea, uric acid, and creatinine to gauge how well the kidneys are working

evaluation of calcium metabolism by tests in the event of calcium deposits

Skin test for tuberculosis:

A little quantity of tubercular antigen is infused into the inner forearm’s skin during this test. If the person has already been exposed to M tuberculosis, a hard red bump (induration) will occur after 2 to 3 days. In around 80% of instances with kidney TB, the test is positive.

Testing urine:

To identify renal tuberculosis, the urine tests listed below may be used:

regular urine testing that might reveal the presence of red blood cells and pus cells

On certain mediums that encourage the development of mycobacteria, urine is cultured. Three to five urine samples collected in the early morning should be used. The availability of the findings is delayed by 4 to 8 weeks.

A particular liquid medium can be used for the culture, which, much like polymerase (PCR), yields speedier results and allows for early infection diagnosis.

Imaging exams

The following imaging studies of a urinary system may be performed to identify renal tuberculosis:

Material is injected into blood during an intravenous pyelogram or intravenous urogram to image the urinary system after it has been processed by the kidneys and passed through. It can identify structural and operational issues brought on by urinary tract TB. To determine if any surgical therapy is required, the testing should be conducted 3 to 4 months following the commencement of the treatment.

A CT scan is helpful in determining the extent of severe kidney disease, and an X-ray may reveal calcium deposits.

ultrasound to track therapy response

How is Renal Tuberculosis Treated?

Anti-TB drugs are used to treat kidney tuberculosis. Due to the possibility of mycobacteria developing resistance, the drugs are provided in combination rather than alone.

The following treatments are provided in India:

• For the first two months of treatment, patients get Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol to kill the majority of the bacteria. After that, patients get therapy with rifampicin and isoniazid for another 4 months in order to eradicate any remaining germs.

• To make sure that patients take their medications on a regular basis, direct observed treatment (DOT), in which the drug is taken beside a healthcare professional, is advised.

• Patients having multidrug resistance are treated with second-line medications for a prolonged period of time, often beginning with an 8-month initial phase and continuing for around a 12-month maintenance phase.

• If ethionamide is administered, the dosage should be decreased in individuals with impaired renal function. In these patients, streptomycin must not be utilized.

• Rifampicin is substituted with rifabutin in HIV patients due to the latter’s significant risk of side effects. Additionally, the course of therapy is extended by nine months.

For urinary tract tuberculosis complications, surgery can be required. Surgery techniques utilized include:

Nephrectomy, which involves removing the damaged or dysfunctional kidney, may be partial or complete.

Procedures to treat injured bladders or ureters that are too thin. To remove the blockage, the constricted ureter may be widened and a stent implanted.

 Treatments including ureteral restoration and reimplantation, urinary diversion procedures, and augmentation cystoplasty may be necessary for those who have severely scarred ureters or urinary bladders (procedure to enlarge the urinary bladder)