Meningitis - H. influenzae
H. influenzae meningitis; H. flu meningitis; Haemophilus influenzae type b meningitis
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 that can cause meningitis. Haemophilus influenzae type b is one kind of bacteria that causes meningitis.
Causes
H. influenzae meningitis is caused by Haemophilus influenzae type b bacteria. This illness is not the same as the flu ( influenza ), which is caused by a virus.
Influenza
The flu is an infection of the nose, throat, and lungs. It spreads easily. This article discusses influenza types A and B. Another type of the flu ...
Before the Hib vaccine, H. influenzae was the leading cause of bacterial meningitis in children under age 5. Since the vaccine became available in the United States, this type of meningitis occurs much less often in children.
H. influenzae meningitis may occur after an upper respiratory infection. The infection usually spreads from the lungs and airways to the blood, then the brain area.
Risk factors include:
- Attending day care
- Cancer
-
Ear infection (
otitis media
) with
H. influenzae
infection
Otitis media
Ear infections are one of the most common reasons parents take their children to the doctor. The most common type of ear infection is called otitis ...
- Family member with an H. influenzae infection
- Native American race
- Pregnancy
- Older age
-
Sinus infection (
sinusitis
)
Sinusitis
Sinusitis is present when the tissue lining the sinuses become swollen or inflamed. It occurs as the result of an infection from a virus, bacteria, ...
-
Sore throat (
pharyngitis
)
Pharyngitis
Pharyngitis, or sore throat, is discomfort, pain, or scratchiness in the throat. It often makes it painful to swallow.
- Upper respiratory infection
- 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
Unconsciousness is when a person is unable to respond to people and activities. Doctors often call this a coma or being in a comatose state. Other c...
- Nausea and vomiting
- Sensitivity to light ( photophobia )
-
Severe
headache
Headache
A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are rare. Most people with headaches can feel much better...
- Stiff neck (meningismus)
Other symptoms that can occur include:
- 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 and irritability in children
- Rapid breathing
- Unusual posture, with the head and neck arched backwards
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 doctor thinks meningitis is possible, a lumbar puncture ( spinal tap ) is done to take a sample of spinal fluid (cerebrospinal fluid, or CSF) 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, and
culture of CSF
Culture of CSF
A cerebrospinal fluid (CSF) culture is a laboratory test to look for bacteria, fungi, and viruses in the fluid that moves in the space around the spi...
Treatment
Antibiotics will be given as soon as possible. Ceftriaxone is one of the most commonly used antibiotics. Ampicillin may sometimes be used.
Corticosteroids may be used to fight inflammation, especially in children.
Unvaccinated people who are in close contact with someone who has H. influenzae meningitis should be given antibiotics to prevent infection. Such people include:
- Household members
- Roommates in dormitories
- Those who come into close contact with an infected person
Outlook (Prognosis)
This is a dangerous infection and it can be deadly. The sooner it is treated, the better the chance for recovery. Young children and adults over age 50 have the highest risk for death.
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
Infants and young children can be protected with the Hib vaccine .
Hib vaccine
All content below is taken in its entirety from the CDC Hib (Haemophilus Influenzae Type b) Vaccine Information Statement (VIS): www. cdc. gov/vaccin...
Close contacts in the same household, school, or day care center should be watched for early signs of the disease as soon as the first person is diagnosed. All unvaccinated family members and close contacts of this person should begin antibiotic treatment as soon as possible to prevent spread of the infection. Ask your provider about antibiotics during the first visit.
Always use good hygiene habits, such as washing hands before and after changing a diaper, and after using the bathroom.
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.
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Haemophilus influenza organism - illustration
This picture shows the organism Haemophilus influenza. Infections caused by Haemophilus influenza usually occur in children under 6 years old and are extremely serious. Haemophilus (type B) is responsible for meningitis, periorbital cellulitis, buccal cellulitis and epiglottitis, septic arthritis, osteomyelitis, pericarditis, and bacteremia. The small organisms live within cells (intracellular) as shown in this picture. (Image courtesy of the Centers for Disease Control and Prevention.)
Haemophilus influenza organism
illustration
-
Haemophilus influenza organism - illustration
This picture shows the organism Haemophilus influenza. Infections caused by Haemophilus influenza usually occur in children under 6 years old and are extremely serious. Haemophilus (type B) is responsible for meningitis, periorbital cellulitis, buccal cellulitis and epiglottitis, septic arthritis, osteomyelitis, pericarditis, and bacteremia. The small organisms live within cells (intracellular) as shown in this picture. (Image courtesy of the Centers for Disease Control and Prevention.)
Haemophilus influenza organism
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.