Small Urinary Tract Stones: The Available Options in Rural Areas

How common are Urinary tract stones?

Urinary tract stones are found in 5 to 15 percent of the population in most countries (1). However, in India there is wide regional variation, and in some areas, the incidence is as high as 7.6% (2). The stones form when the urine is concentrated. Places that have a hot, humid climate like Northeast India have higher incidence of stone formation. In smaller hilly areas that are not cold, people sweat a lot and lose a lot of fluid as sweat, since they do lot of climbing and do not have free access to water.

What causes the formation of the stones?

The most common cause of stone formation is dehydration, as mentioned earlier. This causes less urine and greater concentration of the stone-forming substances in the urine. Hence, people who do strenuous activity without taking adequate fluids are prone to stone formation. About three fourths of the stones are calcium stones. Other substances like uric acid (which are more common in some areas), magnesium ammonium phosphate (which occurs in infected stones called Struvite stones), oxalates, some medicines, etc., contribute to stone formation. Some diseases like gout, parathyroid disease and sometimes even diabetes, inflammatory bowel disease and increased blood pressure contribute to stone formation (3). However, most of the time, the cause is not definitely known and, dehydration contributes to stone formation.

What symptoms do the stones cause?

Many stones can cause no symptoms when they are small. The most common symptom is back pain, typically in the loin or more towards one side in the back. The pain could be severe or mild, and it could radiate or move along to the front side to the groin. Depending on the location of the stone, the pain could be present at the lower abdomen or the tip of the genitalia.

The pain is due to the increased effort of the urinary tract to push the stone out, and stretching of the covering or capsule of the Kidney. It is colicky in nature. The intensity gradually increases and comes down in pulses. Infected stones can cause pus in the urine or foul smelling urine, and also irritation while passing urine. Sometimes blood is present in the urine.

How is the diagnosis made?

The stones in the kidney or bladder could be diagnosed by ultrasound examination. X-ray of the KUB region could help in the diagnosis of stones in the ureter or passage from the kidney to the bladder. However, experts are necessary to make the diagnosis, because they need to know the line of the ureter and the shape of the stone, etc., and small stones could be easily missed by those who do not have much experience. Using contrast material to delineate the urinary tract is called IVU or intravenous urogram. It is expensive and not available in many rural areas. CT scan, MRI, etc., can be used to diagnose stones but are not usually necessary. Sometimes diagnostic cystoscopy might be required for diagnosing the small bladder stone or stones in the urethra.

When is further testing required?

Patients with the following conditions would benefit by metabolic evaluation at a bigger center:

1. Recurrent stones
2. Stones in very young patients
3. Stones on both sides
4. Large number of stones and unusual stones.

Several blood tests and tests carried out on urine collected over a period of 24 hours would be required for these patients.

What are the treatment options that are available for rural patients?

The treatments that are available depend mostly on the size and location of the stone:

1. Small stones up to 5 mm in size: These stones pass out on their own within few weeks (71 to 98%). Plenty of fluids are required, and the only medicines needed are pain killers and anti-inflammatory medicines to decrease the swelling around the stones. Fluids are the most important of these.
2. Stones up to 7 mm in size: These stones, or even the stones of previous category, would benefit by what is called Medical Expulsion Therapy (MET). This consists of special medicines called alpha-1 blockers and calcium channel blockers. They reduce the spasm of the ureteric muscles and encourage peristalsis or movement. These are given along with pain killers and anti-inflammatory medicines.
3. Stones from 7 to 12 mm in size: These stones can pass comfortably if the passage is made wide. The passage could be made wide using a procedure called placing a Double “J” (DJ) stent (6). The DJ stent makes the ureter dilate, sometimes up to three times the original size. It keeps the ureter open all the time, and the up and down movement aids the passage of the stones.
4. 7 to 12 mm stones in the lower calyx: This type of stone is difficult to treat, as they might not come out with placement of the DJ stent. Half of these stones can come out by treatment with special techniques during ureterorenoscopic removal of the stones (7). When stones are located in the ureter, renal pelvis or upper or middle calyces of the kidney, the stones that do not come out with DJ stenting alone could be seen with a ureterorenoscope and broken with lithoclast. In an expert’s hands, the ureterorenoscope can reach the above places after the ureter dilates due to placement of the DJ stents.
5. Larger stones: These are discussed in another article.
6. Stones in the bladder or urethra: These are broken with lithoclast after locating them during cystoscopy. The broken pieces are then washed out.

What are the advantages of the above options?

The treatment options mentioned earlier are minimally invasive. They are carried out through normal urinary passages. The equipment is portable and could be carried to remote places. Spinal anesthesia is used for these procedures, which makes anesthesia less expensive and readily available at most places.

What precautions are necessary?

The DJ stents are foreign bodies and should never be kept in place for more than three months. If kept for a longer time, they can break easily, become infected and patients have even died when people have tried removing stents that were one year old, without sufficient precautions.

Although the DJ stent dilates the passages and prevents the passage from getting blocked, the stent per se does not cause the stones to come out. The stones are flushed out by the passage of urine. Hence, sufficient intake of fluids is necessary in order to pass about 4 liters of urine every day, to ensure free passage of the stone fragments.

Is there any special dietary advice?

The most important thing is to take sufficient fluids, to pass more than 3.5 to 4 liters of urine. Those with uric acid stones should avoid high purine diet like organ meats (like liver and kidney), shellfish, meat and yeast extracts, buttermilk, pulses (like channa and rajma), peas, cauliflower, spinach, beans, mushrooms, and so on. High-calcium diets and cola drinks could also be avoided.

Lemon juice has a stone prevention reputation because of its citrate content. This is because the citrate prevents the calcium from binding to other substances in urine (8).

What are the facilities available at SEESHA?

At Karunya Community Hospital, at ICC hospital in Coimbatore, the Bethesda Hospital at Aizawl, Sielmat Christian Hospital at Churachandpur, Family health hospital Dimapur and other places where the SEESHA health care team provides surgical camp and diagnostic camp facilities, all the treatment modes mentioned above are available. Several papers have been published in national and International journals about these low cost techniques.

Dr. J. Gnanaraj MS, MCh [Urology], FICS, FARSI, FIAGES is a urologist and laparoscopic surgeon trained at CMC Vellore. He has been appointed as a Professor in the Electronics and Instrumentation Engineering Department of Karunya University and is the Director of Medical Services of the charitable organization SEESHA. He has a special interest in rural surgery and has trained many surgeons in remote rural areas while working in the mission hospitals in rural India. He has helped 21 rural hospitals start minimally invasive surgeries. He has more than 150 publications in national and international journals, most of which are related to modifications necessary for rural surgical practice. He received the Barker Memorial award from the Tropical Doctor for the work regarding surgical camps in rural areas. He is also the recipient of the Innovations award of Emmanuel Hospital Association for health insurance programs in remote areas and the Antia Finseth innovation award for Single incision Gas less laparoscopic surgeries. During the past year, he has been training surgeons in innovative gas less single incision laparoscopic surgeries.