Mechanisms Causing Uric Acid Stones

My chapter article on uric acid stones tells about the clinical picture and treatment. But it leaves out how the problem arises. Low urine pH causes uric acid stones, but what causes low urine pH? The superficial answer is low urine ammonia. Kidneys remove our daily acid load via urine ammonia excretion and titration of urine buffers – mainly phosphate. The latter requires the urine pH falls. Kidney ammonia production does fall short of normal in those who produce uric acid stones. As in an endless series of boxes that open to reveal yet another inside, what is wrong with ammonia production? The expected answer was insulin resistance, as in Type Two diabetes. Such diabetics produce unduly acidic urine, form uric acid stones, and certainly exhibit insulin resistance. But no. Nature’s ‘simple news’ has it otherwise. They have normal ammonia production. Why their urine pH is low remains unknown. Read this article to enjoy nature’s quirks and the wonderful sleuthing of the Dallas group that did the main work. But be ware. Nature may tell her simple news with ‘tender majesty’ but she tells it ‘slant’.

Why Delay Prevention

As I thought about modern prevention of the common stone using diet and fluids, I asked myself when treatment should start. Many say why bother unless a person formes multiple stones – as if to qualify as an established stone producer. I think that is not right. My review of published trials shows that the outcome for treated patients dims as they have had more stones before treatment began. Moreover, the ideal diet for stone prevention matches exactly with the ideal diet for the US population. So why wait at all about diet? As for fluids, the same. Why wait. Even more, why wait for the first stone. Stones are very familial. If you have them, your family members are at increased risk. I will not quibble about how much more risk, because I do not care. If the diet is the one we are all supposed to eat, why not eat it now if you have a relative with stones? As for attention to hydration, the same. That impatience led to this article.

Chapter Seven: Uric Acid Stones

Uric acid in stones can be prevented with such absolute certainty that recurrence should be in almost all cases unnecessary. Invariably uric acid forms because of elevated supersaturation that arises mainly from low urine pH with some added effects of urine volume and total uric acid excretion. Of these three, urine pH so predominates one might well say uric acid in stones is a disease of low urine pH. Even though a variety of conditions such as obesity, diabetes, and vascular disease predispose to uric acid stones. all act via low urine pH as a singular final pathway. That low pH is such a singular pathway to their formation makes alkali their singular and sufficient prevention. Therefore, given its simplicity and power, alkali is critical for all patients whose stones contain uric acid. How obesity, diabetes, and vascular disease lower urine pH requires a second and more technical article I promise to write later on. This one focuses on and emphasizes prevention, which means assessment and management of urine uric acid supersaturation and mainly the management of low urine pH through proper alkali use.


The entire TOC is available on the left side of all the articles. Click on the category of interest and it will unfold and show you the related articles as quick links. Any page a link takes you to will have the TOC open to where you last looked.



Kidney Stones

What is In It?

What kidney stones are Structure of stones
Matrix of Stones The organic part of stones
Types of kidney stones A primer showing stone types
Kidney Stone analyses How it is done; how often is it needed
Quality of kidney stone analysis Flaws in commercial labs
Nephrocalcinosis A radiological term easily misunderstood
Kidney Stones Themselves  A review of several articles on stones
Pain from kidney Stones  How stones cause pain
 The Kidney Stone Guide Book Overview of Kidney Stones



What is In It?

The Science of the Kidney Stone Diet Evidence for the kidney stone diet
The Kidney Stone Diet Best diet for stone prevention
The Science and Politics of the US Diet Guidelines From 1977 to 2020 – scandal, politics, how to eat
How to Eat the Kidney Stone Diet Special aspects of the kidney stone diet
How to Eat a Low Salt Diet How to shop and select for low sodium diet
The Low Oxalate Diet Our best oxalate lists and how to use them
High Calcium Low Sodium Diet Our best list of the best bargains
How Much Protein Should you Eat Does protein cause stones or bone disease?
How Much Fluid is Enough How supersaturation varies with urine flow
Variety of Fluids Fluid options and how to plan a day
How to Drink enough Tips on ways to make high fluids a pleasure
The Low Flows What makes some people avoid fluids
ACP Fluid Guidelines  Faulty but useful
Does Water Prevent Kidney Stones – What’s your Bet? Review of water trial data



What is In It?

Cost of potassium citrate How to lower the cost of alkali treatment
Kidney Stone prevention by citrate How citrate prevents stones
Thiazide to Prevent Kidney Stones  The drugs and how they work
Ureteroscopy New techniques vs. old ones
Prevention of Calcium kidney stones The treatment trials and what they say
ACP  Med Guidelines Faulty but useful
Rebuke of ACP Guidelines Critique by an expert
Coke Treatment Probably nonsense but popular on the web



What is In It?

Putting it all together The whole process of prevention
5 Steps to Kidney Stone Prevention Details of the stages in evaluation and treatment
How to Be a Successful Patient Organize properly for medical visits
Take Charge of kidney Stone Prevention A summary with emphasis on diet management
How To Do 24 Hr Urines The central test: Common mistakes you can avoid
Web apps & smart bottles Are fancy new devices worthwhile?
24 hr urines – Ca Stones How to read your own tests
24 hr urines – UA Stones How to read your own tests
My Lab Report: 5 Questions How treatment follows test results
Style of Practice My personal clinical approach to stone prevention
Assessment of Plaque CT estimate of kidney calcium deposits


How Kidney Stones Form

What is In It?

Video: How Kidney Stones Form Crystal formation in kidneys
Growth on Plaque Tissue calcium deposits anchor growing stones
Tubule Plugging Crystals plug nephrons; stones overgrow
Medullary Sponge Kidney A disease with tiny crystals in cysts
Role of Immunity Innate immune system and plaque



What is In It?

An Introduction A simple explanation and home experiment
Video: Supersaturation Serious but narration makes things easier
Use of Supersaturation Role in clinical practice
Why Use 24 Hour Urines?  Benefit of 24 hour urine averages
Science of Supersaturation Review of selected scientific papers
Supersaturation  A review of multiple articles


Urine Risk Factors

What is In It?

Oxalate Physiology  Control of Urine Oxalate
Hypercalciuria in General Idiopathic and from systemic diseases
Idiopathic Hypercalciuria Pathophysiology of IH
How Salt Works Sodium physiology BP and IH
Salt Stones and Bones  Bone disease in IH and role of sodium
How Citrate Works Physiology of urine citrate regulation
Calcium binding Importance of citrate calcium binding
Crystal Inhibition Citrate effects on stone crystals
Citrate and Metastable limits  Citrate inhibition of crystal formation
Dr. Charles Pak An homage to a founder of citrate usage



What is In It?

CaOx Stone Formers General appearance – plaque emphasized
Phosphate Stone Formers Plugging, young women predominate
Medullary Sponge Kidney Case 4: A patient with MSK, shows OR and tissues



How Stones Form

What is In It?

Cystinuria A general overview



Science and medicine

What is In It?

Three Medical Sciences  Discovery, trials, and diagnosis
Science in medicine Basic science in clinical practice
Applied Medical Science  The scientific basis of trials
 Science Marries Medicine Stone disease as an instance