The kidneys are two bean-shaped organs that help in the removal of wastes from the body.
As the kidneys filter blood of impurities, minerals and acid salts can accumulate and harden over time. These solid crystalline deposits are called kidney stones, and can form in one or both kidneys. The stones can travel down the urinary tract and block the flow of urine, causing pain and bleeding.
Kidney stone formation is a common urinary system disorder that can form in any individual. However, men, and overweight people are at a higher risk of developing them.
Kidney stones form when certain salts and minerals in the urine become highly concentrated and build up. This can happen due to
Signs and Symptoms
Symptoms of kidney stone formation may not manifest until the stone moves around the kidney or down into the urinary tract. Symptoms may include:
You should call your doctor if you find it difficult to pass urine, or the pain increases and is accompanied with fever, chills, vomiting and nausea.
When kidney stones are suspected, your doctor may order blood, urine and imaging tests (X-ray, CT scans) to diagnose the condition. You may also be asked to urinate through a sieve to collect and test the kidney stones that pass in the lab. The results will help your doctor to determine the cause and formulate an appropriate plan for treatment.
Treatment depends on the type of stone and its underlying cause. Small kidney stones can be flushed out by drinking plenty of water every day or through medication. Additionally, your doctor may prescribe medication to relieve pain.
For larger stones, your doctor may suggest certain procedures based on the location and size of the kidney stones.
A noninvasive procedure called extracorporeal shock wave lithotripsy may be recommended to break down large stones. Your surgeon will administer sedatives or local anaesthesia to keep you comfortable. The location of the stones is determined with the help of ultrasound or X-rays. Using a device called a lithotripter, high energy sound waves are passed over the area to be treated from outside the body. The shock waves will vibrate and break the stones down without harming the rest of the body. The stone fragments can now easily pass out through the urine.
Sometimes, your surgeon may use insert a stent or tube before or after the procedure through the bladder or the back into the kidney to hold the urinary tube open, preventing the pieces from blocking the tube.
Another alternative procedure your doctor may suggest is ureteroscopy. This can be used for stones in the urinary tract closer to the bladder. A thin lighted tube called an ureteroscope is inserted through your urinary tract opening, so no incisions are needed for the procedure. Once the stone is located, tiny forceps or a basket shaped instrument at the end of the scope grabs and removes the stones. Larger stones are first broken down with a laser before excision.
Sometimes, a more invasive procedure called percutaneous nephrolithotomy may be performed. Your surgeon will make an incision in your back under general, regional or spinal anaesthesia. A hollow tube with a probe is inserted into the incision. Your surgeon can either remove the stones directly or break them into fragments before excising them.
Kidney stones can be prevented by making some lifestyle changes like drinking more water and reducing the intake of excess salt and animal proteins.
Kidney stones can cause severe pain and discomfort, especially during urination. Invasive and noninvasive procedures are used to remove or break the stones to sizes that can easily pass out through the urine and alleviate symptoms.
A ureteric stent is a soft flexible tube that is temporarily placed in the ureter to make a channel for the urine to pass and allow drainage of the kidney. A stent is thus placed when an urologist is concerned that the urine may not drain well through the ureter either due to blockage or following a surgery on or near the ureter or following a procedure involving insertion of an instrument into the ureters and kidney. This is crucial as stagnation of urine even for a small period builds up pressure in the kidney and also increases the risk of infection which may lead to kidney damage. Stents used for an adult patient vary from 24 cm to 30 cm in length. One end of the stent is placed in the kidney and the other end is placed in the bladder. To prevent displacement the stent is coiled at its ends. Stents are usually placed for short periods which may vary from a few weeks to few months and are removed thereafter.
Usually, a stent is placed under general anaesthesia by using a cystoscope which is passed through the urethra into the bladder. The stent is then placed in the ureter and kidney through the opening of the ureter in the bladder. The correct position of the stent is confirmed by an X-ray.
Removal of stent is also performed using a cystoscope, usually, under local anaesthesia. Sometimes, a thread is attached to the lower end of the stent and stays outside the body through the urethra. Such stents can be removed just by pulling the thread. However, removal using cystoscopy may be required if the string breaks while pulling.
Side Effects and Complications
The majority of patients feel the stent and may experience one or more of the following symptoms:
These symptoms usually resolve within 24 to 48 hours when the stent is removed.
Complications associated with ureteral stent may include stent infection, encrustation or migration and hyperplastic urothelial reaction.
Ureteral stent development is underway which is working on new ideas on stent design, composition material and stent coating to eliminate the adverse effects of ureteral stent usage and improve its long term efficacy. Your urologist will discuss the different types of stents that are available and can be helpful in your condition.