Based on an interview with Dr. Hemanth, resident urologist at Thomson Hospital Kota Damansara

Dr Hemanth Kumar Ramasamy
Source: THKD

Kidney stones are one of the most common — and most painful — urological conditions doctors see, and in a hot, humid country like Malaysia, they’re especially prevalent. We sat down with Dr. Hemanth, a urologist with over 20 years of experience treating stone disease, to break down what kidney stones actually are, how to spot them, and how they’re treated.

What exactly is a kidney stone?

A kidney stone is a hard mass that forms when crystals — usually made of calcium oxalate, uric acid, or other minerals — clump together and accumulate in the kidney. There are several different types of stones, and the type someone forms often points to what’s driving it, whether that’s diet, dehydration, or an underlying metabolic issue.

What are the symptoms of kidney stones?

According to Dr. Hemanth, symptoms are largely the same regardless of sex. The hallmark symptom is severe pain, typically on one side of the abdomen just below the ribs — the flank, where the kidney sits — that can radiate downward.

Importantly, a stone sitting quietly in the kidney often causes no pain at all. Pain tends to appear only once a stone drops into the ureter (the tube connecting kidney to bladder) and causes an obstruction. Where that pain is felt depends on where the stone is lodged:

• Upper ureter (closer to the kidney): pain just below the ribs
• Mid-ureter: pain that radiates down toward the groin — the classic “renal colic” or “loin-to-groin” pain
• Lower ureter: pain plus urinary symptoms, such as a constant urge to urinate without actually being able to, or difficulty telling whether the urge is to urinate or defecate

Nausea and vomiting are also common with obstruction. If a stone has been stuck for a while and goes untreated, it can trigger a urinary infection, causing fever, chills, and a generally unwell feeling. Visible blood in the urine (hematuria) can also occur, though most patients present primarily with severe pain.

Because the pain can be so severe and atypical in presentation, it’s sometimes mistaken for a back problem, or — for stones on the right side — appendicitis. Patients often arrive in the emergency department in visible distress and need intravenous painkillers before anything else can be done.

Kidney stones form when crystals clump together and accumulate in the kidney.
Source: Stock image

When does a stone need medical attention?

Most kidney stones are small and pass on their own. As a general rule, the smaller the stone, the higher the odds of spontaneous passage: ureteral stones about 3mm pass without intervention, while stones over about 8–10 mm rarely pass on their own and usually need treatment.

Doctors will want to see a patient with continuous pain or visible blood in the urine. Imaging — typically a plain CT scan — is used to locate and size the stone and to check for obstruction. Modern CT scanners can pick up very small stones, often under a millimetre. Blood tests are also done to check for signs of systemic infection or declining kidney function, both of which are red flags that push doctors toward more urgent intervention rather than a “wait and see” approach.

What are the treatment options?

Treatment depends on the stone’s size, location, and whether it’s causing complications:

• Watchful waiting: Small stones found incidentally, especially in the kidney itself, may simply be monitored.
• Shockwave lithotripsy (ESWL): For stones roughly under 1.5–2 cm, sound waves are focused on the stone from outside the body to shatter it into fragments small enough to pass in the urine. It’s a day-care procedure done under light sedation, with no incisions involved.
• Minimally invasive procedures (ureteroscopy): For stones that need more direct intervention, urologists pass thin scopes up through the urinary tract under general anaesthetic, then use a laser to break the stone into fragments, which are either flushed out or retrieved with a small basket.

How do you prevent kidney stones?

When asked about why stone disease is so common in Malaysia, Dr Hemanth explained that our weather is hot and humid, which predisposes people to dehydration, and Malaysians spend much of their time in air-conditioned spaces, which dries the body out further — on top of a general tendency not to drink enough fluids.

The simplest indicator of whether you’re drinking enough is the colour of your urine: dark, concentrated urine is a sign you need more fluids.

Diet matters too. A high-salt diet promotes crystals sticking together and stone formation, so cutting back on salty food — or at least following a salty meal with extra water — helps reduce risk.

For patients who’ve already had a stone, doctors typically send the stone for lab analysis to identify its composition. Someone with a calcium oxalate stone, for example, may be advised to cut back on oxalate-rich foods like soy products, spinach, and nuts (which are usually found salted in Malaysia).

Pain from kidney stones appear usually when a stone drops into the ureter (the tube connecting kidney to bladder) and causes an obstruction.
Source: Stock image

Can you die from a kidney stone?

Dying directly from a kidney stone is very rare, Dr. Hemanth explained. The real danger comes from complications: if a stone obstructs the urinary tract and leads to a severe infection, that infection can spread into the bloodstream (sepsis), which is life-threatening. This is why prompt imaging, diagnosis, and — when needed — intervention are so important once obstruction is suspected.

If you are experiencing symptoms of kidney stones, please don’t hesitate to book an appointment with our Consultant Urologist, Dr Hemanth Kumar Ramasamy.