What Is Meningitis?
Acute inflammation of the meninges, which are three protective membranes surrounding the brain and spinal cord, is called meningitis. This inflammation is mainly caused by a bacterial, viral, or fungal infection, and sometimes due to certain drugs or toxins, cancer, and other rare types of infection. It is a medical emergency and can be life-threatening, if not detected and treated early.
What Are the Signs and Symptoms of Meningitis?
Early symptoms
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Cold.
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Headache.
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Neck pain.
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Cough.
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Tiredness.
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Fever.
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Ear pain or discharge.
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Muscle pain.
Signs and symptoms in adults
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High fever.
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Neck pain and stiffness.
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Severe headache.
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Nausea and vomiting.
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Confusion.
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Concentration problems.
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Difficulty walking.
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Intolerance to bright light and loud noises.
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Loss of appetite.
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Skin rashes.
Signs in infants
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Constant crying.
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Body and neck stiffness.
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Bulge in the fontanel.
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Poor feeding.
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High fever.
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Irritability.
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Sleepiness.
What Are the Types and Causes of Meningitis?
The types and causes are:
1) Bacterial Meningitis:
This is the most severe type of meningitis and is caused by several types of bacteria. It is highly contagious and spreads through person-to-person contact. This can result in death or permanent
disabilities, if not treated immediately. And many times associated with lung, ear or skin infections. Recent
skull trauma or head and neck surgery allows nasal cavity bacteria to enter the meningeal space. Some of the bacteria that cause this infection are:
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Streptococcus pneumoniae.
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Listeria monocytogenes.
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Neisseria meningitidis.
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Haemophilus influenzae.
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Group B streptococcus.
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Gram negative bacteria.
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Mycobacterium tuberculosis.
Viral Meningitis:
This is the most common type of meningitis and is comparatively less severe than the bacterial type. Infants and people with a weakened immune system are more likely to develop viral meningitis. It can also be spread through person-to-person contact. The viruses that can cause this infection are:
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Non-polio enteroviruses.
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Mumps virus.
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Herpes simplex type 2 virus.
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Chickenpox (Varicella-Zoster virus).
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HIV (human immunodeficiency virus).
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Influenza virus.
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Measles virus.
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Arboviruses (like dengue).
Fungal Meningitis:
This is a rare type of meningitis, and cannot be spread from person-to-person contact. It is caused
when fungus from some other part of the body travels through the bloodstream and infects the
cerebrospinal fluid or spinal cord. Fungal spores are present in the soil and environment and enter the
human body through inhaling dirt or soil. People with a weak immune system (for example, people on immunosuppressants therapy for organ transplants, HIV/AIDS, on long term steroid therapy, and old age with multiple comorbidities like diabetes Mellitus, etc.) are at risk of developing fungal meningitis. Some of
the common fungi that cause this are:
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Cryptococcus.
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Histoplasma.
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Blastomyces.
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Coccidioides.
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Candida species.
Parasitic Meningitis:
This type of meningitis is spread through parasites present in dirt and feces, and on snails, raw fish, and poultry. Eosinophilic meningitis or eosinophilic meningoencephalitis or EM is a type of meningitis that can also be caused by parasites. Here, there is an increase in the levels of eosinophils in the cerebrospinal fluid (CSF). The three most common parasites that cause EM are:
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Angiostrongylus cantonensis.
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Baylisascaris procyonis.
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Gnathostoma spinigerum.
Primary amebic meningoencephalitis (PAM) is a type of fatal meningitis that is caused by microscopic ameba Naegleria fowleri. A person can get infected when water containing the ameba enters the body through the nose.
Non-Infectious Meningitis:
Non-infectious meningitis is caused by certain medicines or other medical conditions like:
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Drugs like NSAIDs, and some antibiotics.
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Head injury.
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Brain surgery.
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Vasculitis.
Is Meningitis Contagious?
Not all types of meningitis are contagious. Meningitis that is caused by bacteria and viruses are contagious, and that caused by parasites and fungus are not contagious. The microorganism spread through coughing, kissing, and sneezing. It can also spread by eating soft cheese, hot dogs, and meat that contain bacteria like Listeria.
How Is Meningitis Diagnosed?
If you have a fever, neck stiffness, increased heart rate, and reduced concentration, your doctor might suspect meningitis. He or she might ask you to get the following tests:
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CBC (complete blood count), CRP (C-reactive protein), and other routine blood tests.
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Blood culture - The presence of bacteria is seen in the blood sample.
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Spinal tap or lumbar puncture - The cerebrospinal fluid (CSF) is collected, as CSF shows low glucose level and increased white blood cells and protein in bacterial meningitis (Raised neutrophils count), fungal and tubercular meningitis (raised lymphocytes count), and normal glucose level with increased WBC (lymphocytes) and protein in viral meningitis. LP is contraindicated in brain mass or tumor or if there is raised intracranial pressure. Hence before doing a lumbar puncture, a CT or MRI scan recommended to rule out above possibilities.
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CT scan or MRI - This imaging might show inflammation or swelling in the head.
What Is the Treatment for Meningitis?
Depending on the type of meningitis, the treatment options are:
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Bacterial meningitis - Intravenous antibiotics ( rd generation Cephalosporin such as Ceftriaxone or Cefotaxime plus Vancomycin) and corticosteroids (start just before the first dose of IV antibiotics and to continue for 4 days) to reduce the risk of complications. If blood or CSF culture is positive, then treat accordingly with proper antibiotics.
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Viral meningitis - Typically only requires supportive therapy. Most cases improve over time with rest, fluids, and painkillers. Herpes simplex and the varicella-zoster virus may respond to antiviral treatment like Acyclovir. Corticosteroids to reduce swelling or anti-seizure medicines for seizures.
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Fungal meningitis - Antifungal medicines like a high dose of Amphotericin B and Flucytosine. Raised ICP is common in fungal meningitis and frequent lumbar punctures helpful to relief from those symptoms.
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Non-infectious meningitis - Hydration, bed rest, and corticosteroids.
Is There a Vaccine Against Meningitis?
Some vaccines that are available for various types of meningitis are:
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Haemophilus influenzae type b (Hib) vaccine.
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Pneumococcal conjugate vaccine (PCV13).
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Pneumococcal polysaccharide vaccine (PPSV23).
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Meningococcal conjugate vaccine (quadrivalent vaccine against group A,C,W135,Y).
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Childhood vaccination with BCG for Tubercular meningitis.
What Are the Risk Factors for Meningitis?
Some of the factors that increase the risk of meningitis are:
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Weakened immunity - HIV infection, chemotherapy, autoimmune diseases, organ transplant, and bone marrow transplant.
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People living in close quarters - Boarding schools, day care centers, and hostels.
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Pregnant women.
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Children under 5 years.
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People working with animals.
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Heavy alcohol abusers.
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Ear or sinus infections.
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Recent head and neck surgery.
What Are the Complications of Meningitis?
The complications associated with meningitis are:
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Vision loss.
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Deafness.
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Memory loss.
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Arthritis.
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Migraines.
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Brain damage.
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Hydrocephalus.
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Subdural empyema.
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Gangrene.
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Shock.
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Death.
Can Meningitis Be Prevented?
Some tips to prevent meningitis are:
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Avoid smoking.
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Stay away from sick people.
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If you have a bacterial infection, take antibiotics.
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Get vaccinated, which will protect you against some types of meningitis.
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Practice good personal hygiene.
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Eat healthily and exercise regularly.
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Cover your mouth and nose when you sneeze.
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Avoid sharing personal items.
Be aware of the signs and symptoms of meningitis, as it will help you get immediate medical attention. To know more about meningitis, consult a neurologist online.