Gram-negative meningitis is an infection of the membranes covering the brain and spinal cord (meninges) caused by bacteria that turn pink when exposed to a special stain (gram-negative bacteria).
Acute bacterial meningitis can be caused by gram-negative bacteria.
Causes of Acute Bacterial Meningitis
Acute bacterial meningitis can be caused by gram-negative bacteria. Bacteria causing gram-negative meningitis include:
- Acinetobacter baumannii
- Enterobacter aerogenes
- Escherichia coli
- Klebsiella pneumoniae
- Pseudomonas aeruginosa
Gram-negative meningitis is much more common in infants than adults.
Risk factors in adults and children include:
- Local infection
- Recent brain surgery
- Recent injury to the head
- Spinal abnormalities
- Spinal fluid shunt placement after brain surgery
- Urinary tract abnormalities
- Urinary tract infection
Symptoms of Acute Bacterial Meningitis
- Mental status changes
- Nausea and vomiting
- Sensitivity to light ( photophobia)
- Severe headache
- Stiff neck
- Symptoms of a bladder, kidney, intestine, or lung infection
Exams and Tests for Acute Bacterial Meningitis
A physical examination may show:
- Fast heart rate
- Low blood pressure
- Stiff neck
For any patient with meningitis, it is important to perform a lumbar puncture (" spinal tap "), in which spinal fluid (known as cerebrospinal fluid, or CSF) is collected for testing.
- Blood culture
- CSF culture
- CT scan of the brain
- White blood cell count
- Spinal fluid tests for white blood cells, glucose, protein
- Special stain of the spinal fluid
Treatment for Acute Bacterial Meningitis
Antibiotic treatment through a vein (IV) usually starts right away. If you have a shunt, it may be removed to get rid of the infection.
Outlook / Prognosis for Acute Bacterial Meningitis
It is important to recognize the symptoms of this meningitis, and seek treatment as soon as possible. Early treatment may prevent serious illness or death.
Many people recover completely, but a large number of people have permanent brain damage or die from this type of meningitis. Between 40% and 80% of patients with gram-negative meningitis do not survive, although these numbers may be improving. The likelihood of survival depends on:
- How quickly the infection is treated
- Other medical conditions that may be present
- The patient's age
Possible Complications of Acute Bacterial Meningitis
- Brain abscess
- Brain damage
- Shock with organ damage
When to Contact a Medical Professional
Go to the emergency room or call the local emergency number (such as 911) if you notice symptoms of meningitis. This condition can be very serious and needs immediate treatment.
Prevention of Acute Bacterial Meningitis
Prompt treatment of related infections may reduce the risk of meningitis.