Gram-negative meningitis is a form of meningitis. The term gram-negative refers to a way of differentiating bacteria. This type of bacteria is typically resistant to drugs and most available antibiotics.
Meningitis is inflammation of the meninges. The meninges are the membranes that cover the brain and spinal cord. Meningitis is a serious condition that requires immediate medical attention.
Gram-negative meningitis is a form of bacterial meningitis caused by gram-negative bacteria. Gram-negative bacteria are a type of bacteria that have a
The World Health Organization (WHO) notes that bacterial meningitis is the most common dangerous form of the disease. They also note that it can be fatal in around
Read on to learn about gram-negative meningitis, including its symptoms, causes, and treatments.
- Escherichia coli (E. coli)
- Klebsiella pneumoniae (K. pneumoniae)
- Pseudomonas aeruginosa (P. aeruginosa)
- Serratia marcescens
Gram-negative bacteria have an outer membrane that differs from gram-positive bacteria. This membrane is difficult for antibiotics to pass through. This means that gram-negative bacteria can be harder to treat than gram-positive bacteria.
This type of bacteria gets its name from the gram stain test. Healthcare professionals use the gram stain to check for infection and categorize bacteria. When performing a gram stain, a healthcare professional takes a sample from the area of possible infection.
The most common samples used for a gram stain test include:
A gram stain uses a stain to check the sample for infection. This stain changes color based on the type of bacteria causing the infection. If it turns purple, the person has an infection caused by gram-positive bacteria. If it turns pink or red, the infection is due to gram-negative bacteria.
Babies who have bacterial meningitis may also show symptoms such as:
- being slow or inactive
- feeding less well
- bulging fontanel, which is the soft spot on the baby’s head
- abnormal reflexes
The CDC also notes that symptoms of bacterial meningitis generally develop 3–7 days after exposure to the causative bacteria.
It is possible to recover from bacterial meningitis. However, it can cause a person to develop certain health issues, such as:
- brain damage
- hearing loss
- learning difficulties
If a person or their child shows any signs of bacterial meningitis, they must seek immediate medical attention.
Gram-negative meningitis occurs when gram-negative bacteria encounter a person’s meninges. This can occur in
- bacteria travel in the blood to the meninges from infection in another part of the body
- bacteria spread to the meninges from an infection in the head, such as a sinus infection
- abnormalities in the dura mater, the tough outer layer of the meninges, allow bacteria into the brain or spinal cord
- bacteria enter the meninges during surgery on the brain or spinal cord
Gram-negative meningitis can result from various types of gram-negative bacteria, such as:
- E. coli
- K. pneumoniae
- P. aeruginosa
- Neisseria meningitidis (N. meningitidis)
- Haemophilus influenzae (H. influenzae)
- being an
older adult or a newborn
- having a weakened immune system
- having health conditions such as diabetes or HIV
- having a cerebrospinal fluid (CSF) leak
- having had a spleen removal
- being among large groups of people
- working with meningitis-causing bacteria
- traveling to areas such as sub-Saharan Africa
- being Native American or Alaskan Native
- going to Mecca during Hajj or Umrah pilgrimage
If a doctor suspects a person has gram-negative meningitis, they may take blood and CSF samples.
Gram-negative bacteria can be resistant to certain antibiotics. This means it is important for a doctor to determine the cause of a person’s meningitis.
A doctor will treat immediately if they believe a person has gram-negative meningitis.
Additional information from
The medications a healthcare professional prescribes may vary depending on the individual’s age, suspected causes of meningitis, and any other medical conditions a person has.
If a person has been in close contact with someone who has bacterial meningitis, a doctor may recommend that they also take antibiotics. People who share a house with someone who has a serious Hib meningitis infection may also have to take antibiotics depending on their:
- immune status
- vaccination status
The CDC recommends the following methods to help reduce the spread of bacterial meningitis and other health issues:
Gram-negative meningitis is an infection of the meninges caused by gram-negative bacteria. These bacteria get their name from their result on a gram stain test.
Gram-negative bacteria can be resistant to certain antibiotics. This means it is important for a doctor to treat gram-negative bacteria with an appropriate antibiotic if they suspect it to be the causative bacteria.
Bacterial meningitis can be fatal. Receiving treatment quickly can help to save a person’s life. If a person or their child has any signs of bacterial meningitis, they must seek immediate medical attention.