[My Kidney Stone Story lol] From Sunday's Agony to Everything I Seriously Researched: Causes, Prevention, and Surgery Costs

Well, it happened: I got a urinary stone lol.

One Sunday morning, a pain like nothing I'd ever felt hit me from my side down to my lower abdomen. Standing hurt. Sitting hurt. Lying down hurt. Being a Sunday, no clinics were open, so I spent the entire day curled up in a ball just enduring it. First thing Monday I rushed to the hospital, where the diagnosis came back almost casually: "That's a ureteral stone." I got painkillers and finally felt human again — but the stone had already grown to 6–8mm, and it is in no hurry to leave.

So I decided to research this thing to the ground. For everyone who landed on this page while searching through the same pain: here is everything the patient himself seriously dug up. (This is a personal story plus my own research notes — for diagnosis and treatment, see a doctor!)

Turns out that pain is one of the "big three" of medicine#

I learned this only afterwards, but the pain of a urinary stone is ranked among medicine's "three great pains," alongside childbirth and trigeminal neuralgia. No wonder it hurt. It's also listed alongside heart attacks and subarachnoid hemorrhage as a common reason people call an ambulance. The incidence in Japan keeps rising year after year — it's now a full-blown "disease of modern life."

Here's how it works. Calcium, oxalate, uric acid and other substances in your urine crystallize and take up residence somewhere in the urinary tract (kidney, ureter, bladder, urethra). Apparently a stone just sitting there often doesn't hurt at all — but the moment a stone formed in the kidney drops into the ureter, a tube only 4–7mm across, hell begins. The hard crystal jams the tube, urine backs up, pressure in the renal pelvis upstream spikes, and the surrounding nerves get hammered. That is "renal colic" — the true identity of the thing that got me that Sunday.

Stones come in types (which one is mine?)#

Reading up on it, I found stones come in several varieties. Four main ones:

At this point I still didn't know which type mine was. (A later test revealed it — the answer is in the sequel linked at the end of this article.)

Who gets stones? (I check every single box)#

Urinary stones are heavily lifestyle-driven. Less exercise thanks to remote work, a Westernized diet — looking down the list of factors pushing the numbers up, all I see is my own life.

1. Sex and age

It used to be pictured as a middle-aged men's disease, but women and younger people are increasingly affected. Lifetime risk is about 15% for men (one in seven!) and about 7% for women. Men peak in their 40s–50s, women after menopause in their 50s and beyond.

2. Metabolic conditions

Obesity, high blood pressure, diabetes — metabolic syndrome raises calcium excretion in the urine and tips it acidic, sending stone risk through the roof. Gout (hyperuricemia) is another red flag. Full disclosure: my visceral fat rating is 15.5 (per my Tanita scale), and I'm on blood pressure medication. Not great, huh~ lol

3. Diet and hydration

The biggest enemy is dehydration. Too little water concentrates the urine and makes crystals form easily. Excess animal protein and salt also help build the "core" of a stone. On weekdays I barely drink anything at work — one or two coffees, that's it. Of course I got a stone.

Coffee: friend or foe? (As a daily coffee drinker, I researched this desperately)#

I drink coffee every morning, so I researched this part like my life depended on it. Online you'll find a war between "coffee is dangerous, it's full of oxalate" and "coffee is good, it's a diuretic." The current scientific consensus seems to be this:

Verdict: coffee itself tends to LOWER the risk

Surprisingly, large epidemiological studies (including Harvard's) show regular coffee drinkers have a roughly 25–30% LOWER risk of stones than non-drinkers. The caffeine's diuretic effect keeps flushing the ureters, and caffeine may also suppress calcium crystallization.

But HOW you drink it matters

Coffee genuinely does contain oxalate. Chain-drinking black coffee while drinking no plain water at all raises your risk. The most recommended way to drink it: add milk. The calcium in milk binds the coffee's oxalate in your gut, and it exits in your stool — dramatically cutting the oxalate that reaches your urine. Seriously?... There are more days than not when I don't even have milk in the fridge.

What does surgery cost? (What happens if this gets worse?)#

With a 6–8mm stone on board, this was the most pressing question. Under 5mm, you can hope for "spontaneous passage" — lots of water and painkillers. But over 10mm, or when the blockage starts harming kidney function, surgery enters the picture. Here's what I found. (Costs below are Japanese figures with the standard 30% insurance copay.)

1. Extracorporeal shock wave lithotripsy (ESWL)

Shock waves from outside the body crush the stone into sand (under ~2mm) without any incision. Often the first choice; takes 30–60 minutes, done as a day procedure or one-night stay.

Cost: roughly ¥60,000–100,000 at 30% copay. But one session doesn't always break the stone, so you may need several. Do it multiple times and the bill balloons fast... and apparently this method can require hospitalization too.

2. Transurethral lithotripsy (TUL)

An endoscope goes in through the urethra and a laser breaks up and removes the stone — no abdominal incision. The standard treatment, usually a 3–4 night stay, and it removes the stone almost with certainty.

Cost: roughly ¥100,000–170,000 at 30% copay including hospitalization. Japan's high-cost medical benefit system caps the final out-of-pocket amount based on income.

3. Percutaneous nephrolithotripsy (PNL)

A small (~1cm) hole through the back into the kidney, then an endoscope crushes and extracts large stones (2cm+, staghorn stones). For the big ones ESWL and TUL can't handle.

Cost: about ¥320,000 even at 30% copay, with a 7–10 day hospital stay. The high-cost benefit system again caps the real out-of-pocket cost.

* All figures are rough estimates and vary by hospital and individual situation.

See what I mean? This is a genuinely expensive disease to operate on. ESWL is popular for being the cheapest and gentlest, but it doesn't always finish the job in one go — a several-hundred-thousand-yen course is entirely possible.

50% recurrence! I'd love to say prevention starts now, but...#

And here's what chilled me most: the 5-year recurrence rate is about 50%. One in two people gets that agony AGAIN. Never again for me, so "drink plenty of water," "milk in the coffee," "go easy on salt and animal protein" — I truly want to commit to all of it. Except I have one fatal, unredeemable weakness: I love Jiro-style ramen (Japan's most gloriously fatty, salty ramen). What do I do...

To everyone searching through the same agony#

The pain of a urinary stone is genuinely cruel, but treatment is well established, and above all it's a disease you can control through lifestyle. Milk in your coffee, plenty of water — a small price to never fear that writhing agony again.

As for my own stone: as of this article, it's still in there lol. What type it turned out to be, which tactics worked and which didn't — the ongoing saga is here → [My Kidney Stone Story, Part 2] Three Months In

* This article is a personal account plus the author's own research notes, not medical advice. If you have severe pain, fever, or blood in your urine, see a urologist immediately.