Stone Disease

Who May Benefit

A consultation may be appropriate if you:

• Have severe loin or flank pain, with or without blood in the urine
• Have a stone seen on ultrasound or CT that has not passed
• Have a large or staghorn stone filling part of the kidney
• Form stones repeatedly and want to understand why, and how to stop
• Have stones in both kidneys, or a stone in a solitary kidney
• Have a stone with associated infection or fever — which requires urgent attention
• Have had previous stone surgery and have residual or recurrent stones
• Have an anatomical abnormality such as PUJ obstruction contributing to stone formation

Seek Urgent Care Rather Than Waiting for an Appointment If You Have

• Fever with loin pain — this may indicate an infected, obstructed kidney, which is a medical emergency
• Severe pain not controlled by oral medication
• Inability to pass urine at all
• Persistent vomiting preventing you from keeping fluids down

Available Treatment Alternatives

Conservative Management

Small ureteric stones, generally under 5 to 6 mm, often pass spontaneously with adequate fluid intake, pain relief and sometimes medical expulsive therapy. This is monitored rather than simply left alone.

Retrograde Intrarenal Surgery (RIRS)

A flexible ureteroscope is passed through the urethra and up to the kidney, and the stone is fragmented with a laser and removed. No incision at all. Suited to stones up to around 2 cm and to lower pole stones in selected cases.

Ureteroscopy and Laser Lithotripsy

The same principle applied to stones lodged in the ureter, with high clearance rates in a single sitting.

Percutaneous Nephrolithotomy (PCNL)

For large or staghorn stones. A small tract is made through the flank into the kidney, and the stone is fragmented and removed. Miniaturised variants use smaller tracts with less bleeding. Dr. Ahlawat published early work on performing bilateral PCNL under a single anaesthetic in selected patients.

Extracorporeal Shock Wave Lithotripsy (ESWL)

Shock waves focused from outside the body break the stone into fragments that pass in the urine. Non-invasive, but less effective for hard or large stones, and fragments must still pass.

Laparoscopic or Robotic Stone Surgery

Reserved for unusual situations — very large stones with associated anatomical abnormality, or where PUJ obstruction needs correcting at the same time.

Investigations Usually Required

• Non-contrast CT of the kidneys, ureters and bladder — the reference standard; identifies stone size, exact position, and density, which predicts how it will respond to treatment
• Ultrasound of the abdomen — useful in pregnancy, in children, and for follow-up where repeated radiation is undesirable
• X-ray KUB — to establish whether the stone is visible on plain film, which helps with follow-up
• Urine analysis and culture — infection must be identified and treated before instrumentation
• Serum creatinine and electrolytes — kidney function, particularly where there is obstruction
• Serum calcium, uric acid and parathyroid hormone — to look for a metabolic cause
• 24-hour urine metabolic profile — for recurrent stone formers; measures volume, calcium, oxalate, citrate and uric acid excretion
• Stone composition analysis — if a stone is passed or retrieved, analysing it directly guides prevention

Important Limitations and Risks

• Stones recur. Without addressing the underlying cause, a substantial proportion of patients form further stones within five to ten years. Treatment removes the stone; prevention keeps it from coming back.
• No treatment guarantees complete clearance. Residual fragments are common after any modality and may grow or cause a further episode of obstruction.
• Ureteric stents are often needed after treatment. They cause urinary frequency, urgency, blood in the urine, and flank discomfort in many patients. A stent must never be left in and forgotten — a forgotten stent encrusts and becomes a serious problem.
• PCNL risks include bleeding, occasionally requiring transfusion or embolisation, injury to adjacent structures, and infection or sepsis.
• Ureteroscopy risks include ureteric injury, stricture formation over time, and infection. Occasionally the ureter is too narrow to allow access, requiring stenting and a second procedure.
• ESWL is less effective for hard stones such as cystine and calcium oxalate monohydrate, and fragments can obstruct the ureter as they pass.
• Infection with obstruction is an emergency. In this situation the priority is urgent drainage, with definitive stone treatment deferred until the infection has settled.
• Repeated CT imaging carries cumulative radiation exposure, which is why ultrasound is preferred for routine follow-up where it is adequate.

What a Consultation Involves

A consultation usually takes 20 to 30 minutes and covers:

• Your history — pain pattern, previous stones and treatments, fluid intake, diet, occupation, medications, and family history
• Review of your imaging — stone size, position and density, and the anatomy of your kidney, all of which determine the best approach
• An explanation of the options — including whether waiting for the stone to pass is reasonable in your case
• Prevention — what your metabolic results show, and specific measures to reduce recurrence rather than generic advice
• Practical planning — whether a stent will be needed, when it will be removed, and expected recovery time
• Your questions

Please bring all previous imaging, any stone analysis reports, and details of previous procedures. If you have passed a stone, bring it — analysing it is genuinely useful.