Shunt Infection
Infection of a brain fluid shunt, often soon after surgery
Quick Facts
- Type: Neurosurgical infection
- Highest risk: First few months after surgery
- Common signs: Fever, headache, irritability
- Treatment: Antibiotics and often shunt revision
Overview
A shunt is a thin tube placed during surgery to drain excess cerebrospinal fluid from the brain to another part of the body, most often to treat hydrocephalus. A shunt infection occurs when bacteria contaminate the shunt or the fluid it drains. Because the shunt connects the inside of the brain's fluid spaces to the body, an infection can cause significant illness and can stop the shunt from working properly.
Shunt infections most often happen within the first few months after the shunt is placed or revised, usually from bacteria that enter at the time of surgery. They are a serious complication that requires prompt medical care, typically including antibiotics and often surgery to remove or replace the infected shunt.
Symptoms
Symptoms can develop soon after surgery or later, and may overlap with signs of shunt malfunction. Common signs include:
- Fever
- Headache
- Nausea and vomiting
- Drowsiness, irritability, or unusual fussiness
- Redness, swelling, tenderness, or fluid along the shunt path or at the incision
- Neck stiffness
- Abdominal pain, if the lower end of the shunt is in the abdomen
In infants, signs may include fever, poor feeding, vomiting, a bulging soft spot, and unusual sleepiness or irritability. Symptoms of serious illness, such as high fever, severe drowsiness, or a stiff neck, need urgent medical attention.
Causes
Shunt infections are usually caused by bacteria that normally live on the skin and enter at the time of surgery. The most common organisms are skin bacteria such as staphylococci. Causes and contributing factors include:
- Surgical contamination: Bacteria entering during shunt placement or revision, the most common route.
- Wound or skin infection: Spreading to the shunt from a nearby infection.
- Bloodstream spread: Less commonly, bacteria reaching the shunt through the blood.
- Abdominal source: Infection involving the abdominal end of the shunt.
Risk Factors
- Recent shunt surgery, especially within the first few months
- Young age, particularly infants and premature babies
- Multiple shunt revisions
- A previous shunt infection
- Skin breakdown or wound problems over the shunt
- A weakened immune system
Diagnosis
Diagnosing a shunt infection involves evaluating symptoms and testing the cerebrospinal fluid:
- Clinical evaluation: Assessing for fever, signs of illness, and redness or swelling along the shunt.
- Fluid sampling: Removing a sample of cerebrospinal fluid, often from the shunt itself, to check for infection and identify the bacteria.
- Blood tests: To look for signs of infection.
- Imaging: Brain imaging and shunt X-rays to assess the shunt and check for associated malfunction.
Treatment
Shunt infections usually require both antibiotics and surgery:
- Antibiotics: Intravenous antibiotics, sometimes given directly into the fluid spaces, chosen based on the bacteria identified.
- Removing the infected shunt: The infected shunt is often removed or externalized, and a temporary external drain may be used to control fluid and pressure while the infection clears.
- Placing a new shunt: Once the infection is treated, a new shunt is placed.
- Supportive care: Monitoring and treatment of symptoms in the hospital.
Prompt, complete treatment is important to clear the infection and protect the brain.
Prevention
- Careful sterile technique during shunt surgery, including preventive antibiotics as recommended
- Good wound care after surgery and keeping incisions clean and dry
- Watching for and promptly reporting redness, swelling, or drainage at the shunt site
- Seeking early care for fever or signs of illness in the weeks after surgery
When to See a Doctor
Anyone with a shunt should seek prompt medical care if they develop fever, headache, vomiting, or redness, swelling, or drainage along the shunt, especially in the weeks after surgery. Seek emergency care right away for:
- High fever with severe headache or a stiff neck
- Increasing drowsiness, confusion, or difficulty waking
- Seizures or loss of consciousness
- In infants, a bulging soft spot, poor feeding, persistent vomiting, or unusual sleepiness
Shunt infections can become serious quickly, so early evaluation is safest. Bring information about the shunt type when seeking care.
Frequently Asked Questions
What are the signs of a shunt infection?
Common signs include fever, headache, nausea and vomiting, drowsiness or irritability, and redness, swelling, or drainage along the shunt path. In infants, watch for fever, poor feeding, a bulging soft spot, and unusual sleepiness. These need prompt medical evaluation.
When are shunt infections most likely?
Most shunt infections occur within the first few months after the shunt is placed or revised, usually from skin bacteria that enter during surgery. Infections can occur later but are less common.
How is a shunt infection treated?
Treatment usually combines intravenous antibiotics with surgery. The infected shunt is often removed or externalized while a temporary drain controls fluid, and a new shunt is placed once the infection clears. Treatment takes place in the hospital.
Is a shunt infection an emergency?
It can be. A shunt infection can cause serious illness and may stop the shunt from working, raising pressure in the brain. High fever, severe headache, a stiff neck, severe drowsiness, or seizures need emergency care.
Can shunt infections be prevented?
Not entirely, but careful sterile surgical technique, preventive antibiotics, and good wound care lower the risk. Watching for and promptly reporting fever or redness, swelling, or drainage at the shunt site helps catch infections early.
References
- Hydrocephalus Association.
- MedlinePlus, U.S. National Library of Medicine.
- American Association of Neurological Surgeons (AANS).
- Centers for Disease Control and Prevention (CDC). Healthcare-associated infections.