A patient comes to the nephrology clinic for a work-up of kidney stones. He has a history of tophi and chronic painful arthritis.

He shakes your hand. See the following picture:

Patient with kidney stones comes to the clinic and shakes your hand. Tophi are noted.

When you shake the patient’s hand, you notice tophi

He then presents you with the stones he has been frequently forming. See the kidney stones the patient has been forming.

Kidney stone is presented. What type of kidney stone is this? — Patient is forming these stones in the context of tophi all over his body.

Please answer the following questions:

What type of stone does this patient most likely have?

Uric acid nephrolithiasis.

The patient has tophi. Tophi are deposits of uric acid crystals that build up in joints because of hyperuricemia or elevated levels of uric acid. Tophi are often linked to gout and appear as bumps under the skin as shown above. These lumps present near the fingers, toes, and other joints.

What are tophi in the context of gout?
A
Fluid-filled sacs around joints
B
Calcium deposits in the bones
C
Solid chalky white masses of uric acid
D
Inflammatory cells in the bloodstream

C
Solid chalky white masses of uric acid

Given the following options, where do tophi typically form in the body with a predilection?
A
Extensor surfaces of the elbows
B
Back muscles
C
Abdominal organs
D
Lower back vertebrae

A
Extensor surfaces of the elbows

How do tophi affect bone health?
A
They promote bone growth
B
They strengthen bone density
C
They can directly erode bone
D
They have no impact on bones

C
They can directly erode bone

How can uric acid kidney stones be dissolved in most cases?
A
Increasing uric acid levels
B
Decreasing urinary pH
C
Decreasing hyperuricosuria
D
Increasing urinary pH and volume

D
Increasing urinary pH and volume

Discussion:

➡️Learn More⬅️

Tophaceous Gout and Uric Acid Kidney Stones

Gout With Tophi

Tophaceous gout is characterized by stone-like deforming nodular deposits of urate crystals in connective tissue, known as gouty tophi. These tophi are solid chalky white masses of uric acid surrounded by inflammatory cells and fibrous tissue. They are commonly found around joints and soft tissues, with a preference for specific areas like the elbows, distal Achilles tendon, fingers, and ears. Tophi can vary in size from millimeters to several centimeters and can erode bone, leading to functional impairment.

Tophi can be diagnosed clinically or detected on radiography and may cause ulceration of the skin.
Infections associated with tophi can be challenging to treat because of their avascular nature.
Draining tophi on the hand of a patient are sometimes visible, and can be a clue to the cause of a patient’s kidney stones.

Uric Acid Nephrolithiasis

Uric acid stones is a type of kidney stone disease resulting from the accumulation of uric acid crystals in the kidneys. These crystals can form stones, leading to painful urinary tract obstructions that may recur. The condition is often linked to elevated uric acid levels in the blood (hyperuricemia) and can be influenced by various factors such as diet, genetics, and medical conditions like metabolic syndrome, obesity, diabetes, and hypertension.