Meningitis - gram-negative
Gram-negative meningitis
Meningitis is present when the membranes covering of the brain and spinal cord become swollen and inflamed. This covering is called the meninges.
Bacteria are one type of germ that may cause meningitis . Gram-negative bacteria are a type of bacteria that behave in a similar manner in the body. They turn pink when tested in the laboratory with a special stain called Gram stain.
Meningitis
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.
Causes
Acute bacterial meningitis can be caused by different Gram-negative bacteria including meningococcal and H influenzae .
Meningococcal
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges. Bacteria are one type of germ ...
H influenzae
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges. Bacteria are one type of germ ...
This article covers Gram-negative meningitis caused by the following bacteria:
- Escherichia coli
- Klebsiella pneumoniae
- Pseudomonas aeruginosa
- Serratia marsescens
Gram-negative meningitis is more common in infants than adults. But it can also occur in adults, especially those with one or more risk factors. Risk factors in adults and children include:
- Infection
- Recent brain surgery
-
Recent
injury to the head
Injury to the head
A head injury is any trauma to the scalp, skull, or brain. The injury may be only a minor bump on the skull or a serious brain injury. Head injury c...
- Spinal abnormalities
-
Spinal fluid
shunt
placement after brain surgery
Shunt
Ventriculoperitoneal shunting is surgery to treat excess cerebrospinal fluid (CSF) in the brain (hydrocephalus).
- Urinary tract abnormalities
-
Urinary tract infection
Urinary tract infection
A urinary tract infection, or UTI, is an infection of the urinary tract. The infection can occur at different points in the urinary tract, including...
- Weakened immune system
Symptoms
Symptoms usually come on quickly, and may include:
-
Fever
and chills
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
-
Mental status changes
Mental status changes
Confusion is the inability to think as clearly or quickly as you normally do. You may feel disoriented and have difficulty paying attention, remembe...
- Nausea and vomiting
- Sensitivity to light ( photophobia )
- Severe headache
- Stiff neck (meningismus)
- Symptoms of a bladder, kidney, intestine, or lung infection
Other symptoms that can occur with this disease:
- Agitation
-
Bulging fontanelles
in infants
Bulging fontanelles
A bulging fontanelle is an outward curving of an infant's soft spot (fontanelle).
- Decreased consciousness
- Poor feeding or irritability in children
- Rapid breathing
-
Unusual posture, with the head and neck arched backwards (
opisthotonos
)
Opisthotonos
Opisthotonos is a condition in which a person holds their body in an abnormal position. The person is usually rigid and arches their back, with thei...
Exams and Tests
The health care provider will perform a physical exam. Questions will focus on symptoms and possible exposure to someone who might have the same symptoms, such as a stiff neck and fever.
If the provider thinks meningitis is possible, a lumbar puncture ( spinal tap ) will likely be done to remove a sample of spinal fluid for testing.
Spinal tap
Cerebrospinal fluid (CSF) collection is a test to look at the fluid that surrounds the brain and spinal cord. CSF acts as a cushion, protecting the b...
Other tests that may be done include:
-
Blood culture
Blood culture
A blood culture is a laboratory test to check for bacteria or other germs in a blood sample.
-
Chest x-ray
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
-
CT scan of the head
CT scan of the head
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
- Gram stain, other special stains
Treatment
Antibiotics will be started as soon as possible. Ceftriaxone, ceftazidime, and cefepime are the most commonly used antibiotics for this type of meningitis. Other antibiotics may be given, depending on the type of bacteria.
If you have a spinal shunt, it may be removed.
Outlook (Prognosis)
The earlier treatment is started, the better the outcome.
Many people recover completely. But, many people have permanent brain damage or die of this type of meningitis. Young children and adults over age 50 have the highest risk for death. How well you do depends on:
- Your age
- How soon treatment is started
- Your overall health
Possible Complications
Long-term complications may include:
- Brain damage
-
Buildup of fluid between the skull and brain (
subdural effusion
)
Subdural effusion
A subdural effusion is a collection of cerebrospinal fluid (CSF) trapped between the surface of the brain and the outer lining of the brain (the dura...
-
Buildup of fluid inside the skull that leads to brain swelling (
hydrocephalus
)
Hydrocephalus
Hydrocephalus is a buildup of fluid inside the skull that leads to brain swelling. Hydrocephalus means "water on the brain. "
- Hearing loss
-
Seizures
Seizures
A seizure is the physical findings or changes in behavior that occur after an episode of abnormal electrical activity in the brain. The term "seizure...
When to Contact a Medical Professional
Call the local emergency number (such as 911) or go to an emergency room if you suspect meningitis in a young child who has the following symptoms:
- Feeding problems
- High-pitched cry
- Irritability
- Persistent unexplained fever
Call the local emergency number if you develop any of the serious symptoms listed above. Meningitis can quickly become a life-threatening illness.
Prevention
Prompt treatment of related infections may reduce the risk of meningitis.
References
Nath A. Meningitis: bacterial, viral, and other. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 412.
Tunkel AR, Van de Beek D, Scheld WM. Acute meningitis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, Updated Edition . 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 89.
-
Central nervous system - illustration
The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.
Central nervous system
illustration
Review Date: 7/31/2016
Reviewed By: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA.Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.