Staghorn Calculus

A staghorn calculus is a branching type of kidney stone. In this case, calculus means a stone. The plural is calculi or stones. The name staghorn refers to the shape of this type of stone, which has branches like a piece of coral or the antlers on a deer. The way these stone branches grow can block the drainage system for pee within your kidney. This can lead to kidney failure, which is why a staghorn calculus is serious. Prompt treatment is important.

You can get a staghorn-shaped calculus if you have repeated urinary tract infections (UTIs). A staghorn calculus that forms due to infections may be made of struvite. This is a mix of magnesium, phosphate and ammonium.

Staghorn kidney stones aren’t a common type of stone. Usually, a staghorn stone is only in one kidney, but it can happen in both kidneys.

Symptoms of staghorn calculus

A staghorn kidney stone can be painful enough that you can’t find a comfortable position. Usually, this pain is mild. You can treat it with over-the-counter (OTC) medications, like acetaminophen and ibuprofen. But rarely, it can be severe enough that you need opioids for the pain. This pain may be on your side between your ribs and hip.

Other symptoms of a staghorn kidney stone may include:

• Fever
• Blood in your pee
• Pus in your pee
• Fatigue

Staghorn calculus causes

Repeated urinary tract infections can cause a staghorn calculus. This is likely when the bacteria that cause the infections make an enzyme called urease. One of these germs is Proteus mirabilis. This causes your urine to become less acidic. In turn, crystals can form and lead to a kidney stone. Other causes include:

• Atypical anatomy that makes it more likely for stones to form
• Blockages in your urinary tract
• Long-term use of a urinary catheter
• Previous urinary diversion procedure
• Neurogenic bladder
• Long-term untreated kidney stones

Risk factors

Females are more likely to develop staghorn calculi. Others more at risk include those who have spinal cord injuries or have had many UTIs. If you have a history of weight loss surgery, Crohn’s disease or have had parts of your intestines removed, you’re also at increased risk for kidney stones and staghorn calculi.

Complications of this condition

Staghorn stones can cause complete or partial blockages in your kidneys. The branches of a staghorn kidney stone grow into the renal pelvis. This is the funnel-shaped structure that collects pee and passes it down the two thin tubes of muscles called ureters. Pee travels from the ureters to the bladder, which stores pee. A blocked renal pelvis or ureter can lead to swelling in your kidney.

A staghorn stone can also block your calyces. These are the places in your kidney where urine collection starts. Excess fluid can make your calyces swell and dilate. Without treatment, this can lead to kidney failure.

Lastly, the surfaces and insides of staghorn stones can act as a home for bacteria. This can lead to frequent urinary tract infections that return soon after treatment or never really go away. These infections can also damage your kidneys over time, in addition to causing serious discomfort.

How doctors diagnose staghorn calculus

A healthcare provider will do a physical exam and ask you about your medical history. They’ll ask about urinary tract infections, previous surgeries, pain and other issues you may have.

Your provider may order tests like:

• Blood tests
• Urinalysis
• Renal scan
• Computed tomography (CT) scan

How is it treated?

Staghorn calculus treatment usually means surgery. A healthcare provider must remove the entire stone, even small pieces. This gives you the best chance of avoiding an infection or the formation of new stones.

You may need more than one kind of treatment. Options include:

• Percutaneous nephrolithotomy (PCNL): This is a treatment to break up and remove kidney stones that are too large to pass on their own. It’s the first-choice treatment for most cases due to the size of staghorn stones.
• Ureteral stent: This is a temporary, small plastic tube that a provider places in your ureter. It can unblock your kidney, help drain urine from your kidney into your bladder and help your ureter stay open after surgery.
• Ureteroscopy: A provider removes stones by driving a scope through your ureters, the tubes that connect the kidney to the bladder.
• Laser lithotripsy: A provider uses a laser to break up staghorn kidney stones. This usually happens during a ureteroscopy, as well as a PCNL.
• Nephrectomy: This is the removal of your entire kidney. In the case of a staghorn stone, surgeons only perform this if your kidney is severely damaged and has little remaining meaningful function.

Recovery time

The recovery varies depending on the type of treatment. Recovery from a minimally invasive procedure can take two to four weeks. Any kind of open surgery will require a longer period of recovery. With most kidney stone surgeries, you can go home the same day. Your provider will let you know when you can go back to work and when you can lift heavy objects.

Treatments aren’t always 100% effective. You may have small fragments of stone left over. Most of the treatments may involve some blood loss. Your provider may prescribe antibiotics and pain relievers after the procedure. There’s also a risk of infection because pee isn’t sterile or clean.

When should I see my healthcare provider?

Call your provider or seek medical help after your treatment for staghorn calculus if:

• You have a fever of 100 degrees Fahrenheit (37.8 Celsius) or higher
• You have chills and/or are shaking
• Your bleeding doesn’t stop or gets worse
• Your pain doesn’t improve or gets worse
• You aren’t able to pee

You may want to ask your provider:

• How likely is it that this stone will come back?
• Do I need to take antibiotics?
• How successful is the treatment in most cases?
• Is there anything I can do to prevent the stones from returning?

What can I expect if I have staghorn calculus?

The prognosis (outlook) for staghorn calculus depends on the success of your treatment. After treatment for a staghorn stone, you may or may not develop another stone. But you should be able to pee normally. You shouldn’t be in pain anymore.

Without treatment for a staghorn kidney stone, you may develop other conditions, like:

• Xanthogranulomatous pyelonephritis: This is a rare kidney infection that can cause sepsis. It usually requires kidney removal.
• Caliectasis: Fluid retention causes swelling and dilation (widening) in the calyces of your kidney.
• Kidney failure: Your kidneys become unable to filter out toxins. This can be fatal.
• Urosepsis: This is a severe urinary tract infection. It can be fatal.

Some people who can’t have a surgical procedure are able to do well enough with nonsurgical treatment. Providers call this conservative management. You can live with a staghorn calculus with regular visits to your provider. This involves a physical exam, imaging and blood tests once or twice a year.

How do I prevent staghorn kidney stones?

You may be able to stop a stone from reforming if you:

• Eat or avoid specific foods
• Stay well-hydrated
• Take acetohydroxamic acid, a urease inhibitor (this is rare and risky)
• Take antibiotics to prevent infections