THIRUVANANTHAPURAM: Urinary stone is a very common health issue. As it causes severe pain and morbidity, patients are being compelled to take abstinence from work. Urinary stone disease, also known as urolithiasis implies the formation of solid stones in the urinary tract. The location of stones varies from kidney, ureter, urinary bladder and urethra. The usual place of origin of stones is either kidneys or urinary bladder.
Symptoms
The most common symptom caused by urinary stones is the pain. The location of pain would vary depending on the location of the stone. A stone that obstructs the ureter or renal pelvis causes excruciating pain that radiates from the flank to the groin or to the inner thigh. This pain, known as renal colic, is commonly accompanied by urinary urgency, restlessness, hematuria (blood in urine), sweating, nausea, and vomiting.
It is typically described as colicky pain as it occurs in intervals in a crescendo pattern lasting 20 to 60 minutes caused by peristaltic contractions of the ureter as it attempts to expel the stone. The embryological link between the urinary tract, the genital system, and the gastrointestinal tract is the basis of the radiation of pain to the gonads, as well as nausea and vomiting that are also common in urolithiasis. Fever that accompanies pain due to urinary stones may be an ominous sign that points towards infection. This would mandate prompt treatment for relieving obstruction due to stone and also an aggressive treatment of infection.
Dietary factors
Treatment
The treatment depends on various factors like location and size of stones, the presence of the obstruction to the urinary tract, co-existing alteration in kidney function, co-existing urinary infection etc. The common tests performed are Urine analysis, Ultrasound scan (USS) and X-ray of the abdomen. CT scan has also increasingly used to diagnose stone disease. Small stones in the kidneys are usually treated with painkillers.
Further treatment relies on patients’ ability to tolerate pain and their circumstances. Stones which are refractory to medical treatment and stones which are larger in size are treated with procedures that aim at clearance of stones. If there is associated infection, any procedure to clear stones is done only after treating it. When there is a concurrent infection, a procedure called stenting is done to allow relief. The following are the usual procedures adopted to clear urinary stones
Extra-corporeal Shock Wave Lithotripsy (ESWL) - This modality uses shock waves to fragment stones inside the kidney or upper ureter. It is difficult to treat large stones and hard stones with this modality. There is also a chance of stone fragments getting stuck in the ureter causing pain.
Per Cutaneous Nephro Lithotripsy (PCNL) - This minimally invasive ‘keyhole’ surgery involves putting the instrument directly into the kidney to clear stones.
Ureteroscopy - This procedure involves the introduction of instruments through the urethra into the bladder and then into the ureter to visualize the stone and fragment the stones. Ureteric stones are best treated by this method.
Cystolitholapaxy - This is the process of breaking bladder stones mechanically with an instrument called lithotrite. This instrument is introduced into the bladder through the urethra.
Laparoscopy - This is another kind of ‘keyhole’ surgery to clear selected stones in the kidney or ureter.
If a stone is passed out through urine, this can be analysed to get information about the measures to prevent it in future. Many patients would require 24-hour urine collection for analysis to have a detailed evaluation of metabolic abnormalities that can cause stones.
Dietary modifications to prevent stones should be done in consultation with a nutrition specialist. Uric acid stones are prevented by avoiding food which is high in purine content. Oxalate stones would mandate restriction of leafy vegetables, nuts, chocolate, amla, grapes etc which are rich in oxalates. Dilution of urine indicated by a pale yellow colour will help in preventing its formation. Above all, it is always better to prevent stones rather than treating them after they are formed.
Dr Renu Thomas
Consultant Urologist and Transplant Surgeon
KIMS, Thiruvananthapuram
(The views expressed by the author areher own)