Signs and symptoms of meningeal inflammation have been recorded in countless ancient texts throughout history, but the term ‘meningitis’ became common after surgeon John Abercrombie defined it in 1828.
Definition
Meningitis is a clinical syndrome characterized by inflammation of the meninges. The meninges are the three membranes (the dura mater, arachnoid mater, and pia mater) that line the vertebral canal and skull enclosing the brain and spinal cord. Arachnoid mater and pia mater are called leptomeninges. Therefore, meningitis is the inflammation of leptomeninges including the subarachnoid space leading to a constellation of signs and symptoms and the presence of inflammatory cells in the cerebrospinal fluid (CSF).
Classification
It is vital to know the specific cause of meningitis because the treatment differs depending on the cause.
- Bacterial meningitis. Meningitis caused by bacteria can be deadly and requires immediate medical attention. Some people with the infection die and death can occur in as little as a few hours. Most people recover from bacterial meningitis but can have permanent disabilities such as brain damage, hearing loss, and learning disabilities.
- Viral meningitis. Meningitis caused by viruses is serious but often less severe than bacterial meningitis. This is the most common type of meningitis and people diagnosed with this type may get better without treatment.
- Fungal meningitis. Meningitis caused by fungi is rare, but people can acquire it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
- Parasitic meningitis. Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Parasitic meningitis is much less common than viral and bacterial meningitis. Some parasites can cause a rare form of meningitis called eosinophilic meningitis, eosinophilic meningoencephalitis, or EM.
- Amebic meningitis. Primary amebic meningoencephalitis (PAM) is a rare and devastating infection of the brain caused by Naegleria fowleri. Naegleria fowleri is a free-living microscopic ameba that lives in warm water and soil.
- Non-infectious meningitis. Some cancers, systemic lupus erythematosus, certain drugs, head injury, and brain injury can cause meningitis.
Other Definitions
- Acute meningitis. Acute meningitis is defined as the onset of symptoms of meningeal inflammation over the course of hours to several days.
- Chronic meningitis. Chronic meningitis is defined as at least 4 weeks of symptoms of inflammation of the meninges.
- Aseptic meningitis. Aseptic meningitis refers to a syndrome consistent with signs and symptoms of meningeal inflammation but with negative routine CSF cultures.
- Recurrent meningitis. Recurrent meningitis is defined as at least two episodes of signs and symptoms of meningeal inflammation with associated CSF findings separated by a period of full recovery.
Etiology/Risk Factors
Most cases of meningitis are caused by an infectious agent that has colonized or established a localized infection elsewhere in the host. Risk factors include the following.
- Chronic medical disorders, such as renal failure, diabetes, adrenal insufficiency, and cystic fibrosis.
- Extremes of age. This includes ages <5 or >60 years. The rates of the disease are highest in children younger than 1 year, with a second peak in adolescence.
- Undervaccination. The incidence is presumed to be higher in developing countries because of less access to preventive services, such as vaccination.
- Immunosuppressed states. Immunosuppression increases the risk of opportunistic infections and acute bacterial meningitis.
- Living in crowded conditions. Crowding such as that experienced by military recruits and college dorm residents increases the risk of outbreaks of meningococcal meningitis.
- Exposure through travel to endemic areas or vectors. Borrelia burgdorferi in clients with travel to Lyme endemic areas may acquire the disease.
- Pregnancy. Pregnancy increases the risk of an infection caused by listeria bacteria, which also may cause meningitis. The infection increases the risk of miscarriage, stillbirth, and premature delivery.
Epidemiology
In the United States, the annual incidence of bacterial meningitis is approximately 1.38 cases/100,000 population with a case fatality rate of 14.3%. The highest incidence of meningitis worldwide is in an area of sub-Saharan Africa dubbed “the meningitis belt” stretching from Ethiopia to Senegal.
With almost 4100 cases and 500 deaths occurring annually in the United States, bacterial meningitis continues to be a significant source of morbidity and mortality. Black people have a higher reported rate of meningitis than white people and Hispanic people. Pneumococcal vaccine and universal screening of pregnant women for group B streptococcus have further decreased the incidence of meningitis among young children but the burden of bacterial meningitis is now borne by older adult.
Pathophysiology
Meningitis typically occurs through two routes of inoculation:
- Hematogenous seeding. Bacteria colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.
- Direct contiguous spread. Organisms can enter the CSF via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma), or during operative procedures.
Presentation
The classic triad of meningitis consists of fever, nuchal rigidity, and altered mental status, but not all clients have all three, and almost all clients have headaches. Altered mental status can range from irritability to somnolence, delirium, and coma. Most clients with bacterial meningitis have a stiff neck, but the meningeal signs are insensitive to the diagnosis of meningitis. Increased blood pressure with bradycardia may also be present. Vomiting occurs in 35% of clients.
In adults, the physical exam is centered on identifying focal neurologic deficits, meningeal irritation (Brudzinski and Kernig signs), and particularly in meningococcal meningitis, characteristic skin lesions (petechiae and purpura). Cranial nerve abnormalities are seen in 10-20% of clients.
Signs and symptoms are less evident in neonates and infants. They can present with or without fever or hypothermia, decreased oral intake, altered mental status, irritability, and bulging fontanelles. It is important to obtain full perinatal history and vaccine records.
Diagnostic Considerations
Meningitis can be diagnosed based on medical history, physical examination, and diagnostic tests. Common tests to diagnose meningitis include:
- Blood studies. In clients with bacterial meningitis, a complete blood count (CBC) with differential will demonstrate polymorphonuclear leukocytosis with a left shift. A coagulation profile and platelet count are indicated in cases of chronic alcohol use, chronic liver disease, or suspected disseminated intravascular coagulation (DIC).
- Blood cultures. Obtaining cultures before instituting antibiotics may be helpful if the diagnosis is uncertain. The utility of cultures is most evident when the lumbar puncture is delayed until head imaging can rule out the risk for brain herniation, in which cases adjunctive dexamethasone and antimicrobial therapy are rightfully initiated before CSF samples can be obtained.
- Imaging. Computed tomography (CT ) scans of the head and magnetic resonance imaging (MRI) of the brain generally does not aid in the diagnosis of meningitis. Imaging may be useful in finding complications of meningitis and in determining parameningeal causes of abnormal CSF.
- Spinal tap. A definitive diagnosis of meningitis requires a spinal tap to collect CSF. In clients diagnosed with meningitis, the fluid often shows a low glucose level along with an increased white blood cell count and increased protein.
Medical Management
Managing the airway, maintaining oxygenation, giving sufficient intravenous fluids while providing fever control are parts of the foundation of meningitis management.
- Intravenous crystalloids. If the client is in shock or hypotensive, crystalloid is infused until euvolemia is achieved.
- Seizure precautions. If the client’s mental status is altered, seizure precautions are considered. Seizures should be treated according to the usual protocol, and airway protection should be considered.
- Antibiotic therapy. It is vital to institute empiric antimicrobial therapy as soon as possible. The choice of agents is usually based on known predisposing factors, initial CSF Gram stain results, or both. Once the pathogen has been identified and antimicrobial susceptibilities determined, the antibiotics may be modified for optimal targeted treatment.
- Steroid therapy. The use of corticosteroids as an adjunctive treatment for bacterial meningitis improves outcomes by attenuating the detrimental effects of host defenses. The use of steroids has been shown to improve the overall outcome of clients with certain types of bacterial meningitis, including h. Influenzae, tuberculous, and pneumococcal meningitis.
- Antiviral therapy. In certain instances, specific antiviral therapy may be indicated, if available. Instituting antiretroviral therapy may be necessary for clients with HIV meningitis that occurs during an acute seroconversion syndrome. Ganciclovir and foscarnet are used for cytomegalovirus meningitis in immunocompromised hosts.
- Antifungal therapy. In resource-limited areas, amphotericin B and fluconazole are the optimal agents for the treatment of HIV-related acute cryptococcal meningitis.
Prevention
Vaccination and chemoprophylaxis are two means of preventing meningitis. Common bacteria or viruses that can cause meningitis can spread through coughing, sneezing, kissing, or sharing eating utensils, a toothbrush, or a cigarette.
- Hand hygiene. Careful hand washing helps prevent the spread of pathogens. Teach clients and family members to wash hands often, especially before eating and after using the toilet, spending time in a crowded public place, or petting animals.
- Proper food preparation. Reduce the risk of listeria infection in pregnant women by cooking meat, including hotdogs and deli meat, to 165℉ (74℃). Instruct to avoid cheeses made from unpasteurized milk and choose cheeses that are clearly labeled as made with pasteurized milk .
- H. influenzae vaccine. Vaccination against H influenzae type B (Hib) is strongly recommended
- in susceptible individuals. Vaccination against s pneumoniae is also strongly encouraged for susceptible individuals, including people older than 65 years and individuals with chronic cardiopulmonary illnesses.
- Pneumococcal vaccine. The Advisory Committee on Immunization Practices (ACIP) recommends the administration of a 13-valent pneumococcal polysaccharide-protein conjugate vaccine as part of routine childhood immunization. Vaccination against measles and mumps effectively eliminates aseptic meningitis syndrome caused by these pathogens.
- Chemoprophylaxis. After exposure to an index case involving H influenzae, N meningitidis, or S pneumoniae, temporary nasopharyngeal carriage of the organism is typical. This is the basis for the recommendations on chemoprophylaxis. However, prophylaxis does not treat incubating invasive disease. Rifampin is given to eliminate nasopharyngeal carriage of Hib and to decrease invasion of colonized susceptible individuals.
Nursing Management
The approaches to nursing care for all types of meningitis are similar. Nursing responsibilities for a client diagnosed with meningitis include performing frequent neurological checks and maintaining an accurate recording of vital signs and intake and output. Meningitis is always a serious disorder because it can run a rapid, fulminating, and possibly fatal course. If symptoms are recognized early and treatment is effective, the client will recover with no sequelae.
Nursing Assessment
Approximately 25% of clients with bacterial meningitis present acutely, well within 24 hours of the onset of symptoms. The atypical presentation may be observed in certain groups such as older adults.
Subjective Cues
- Poor feeding or eating
- Severe headache
- Drowsiness
- Somnolence
- Malaise
- Stiff neck
- Nausea
Objective Cues
- Fever
- Nuchal rigidity
- Irritability
- Delirium
- Coma
- Hypertension
- Bradycardia
- Vomiting
- Non-blanching petechiae
- Cutaneous hemorrhages
- Increased ICP
- Brudzinki sign
- Kernig sign
Infants
- Bulging fontanelle
- Paradoxic irritability
- High-pitched cry
- Hypotonia
Nursing Diagnosis
- Acute pain related to meningeal irritation
- Risk for ineffective cerebral tissue perfusion related to increased ICP
- Risk for infection (progression of sepsis to septic shock) related to failure to recognize or treat infection
- Hyperthermia related to infectious and inflammatory processes
- Disturbed thought processes related to CNS infection by HIV
- Risk for trauma related to seizures
Nursing Desired Outcomes
- The client will achieve a timely resolution of current infection without complications.
- The client will identify interventions to prevent and reduce the risk and spread of a secondary infection.
- The client will demonstrate temperature within the normal range and be free of chills.
- The client will maintain the usual reality orientation and optimal cognitive functioning.
- The client will report tolerable pain and show no signs of facial grimacing or discomfort.
Nursing Interventions
- Place in a comfortable position. The client may feel pain when the head is flexed forward, therefore, they are usually more comfortable without a pillow. Avoid flexing the neck forward when turning or positioning the client.
- Provide accurate and honest information. Make certain that the client and caregiver receive a good explanation of everything that is happening and provide extra attention from the healthcare team so that the client may feel secure, especially during painful procedures. Explain that changes in mental status are caused by the disease process.
- Reduce environmental stimulation. Promote rest by keeping stimulation in the room to a minimum. Organize care so that the client is disturbed as little as possible. The room should be dimly lit and the noise kept to a minimum. Avoid startling the client by using a soft voice and gentle touch these measures ensure that the client will not continue having an increased ICP which could lead to seizures.
- Monitor vital signs closely. Frequent monitoring of vital signs is necessary. A slow pulse rate, irregular respirations, and increased blood pressure should be reported immediately because they could indicate increased ICP.
- Institute measures to decrease hyperthermia. Antipyretics, a sponge bath, or a cooling mattress may be provided to control fever.
- Monitor intake and output. Carefully observe the client’s intake and output and document them. Provide strict attention to the maintaining IV line to avoid overhydration and increased ICP. Promptly report a decrease in urine output, which could signal urinary retention.
- Provide appropriate dietary measures. As the client’s condition improves, the diet may progress from clear fluids to an age-appropriate diet. A special formula may be given when nasogastric feedings are necessary.
- Monitor the client’s neurological status. The nurse should continue to monitor the client’s neurological status and record and report findings such as weakness of the limbs, speech difficulties, mental confusion, and behavior problems.
- Observe seizure precautions. Remove items from surroundings that can be dangerous. Ensure that cardiac monitoring and oxygen are readily available, and padding may be applied to the bed frame as appropriate.
Evaluation
- The client’s infection is resolved without undue complications.
- The client identified measures that will prevent or reduce the risk of a secondary infection.
- The client’s vital signs were restored to within the acceptable range.
- The client’s mental status is maintained at its usual normal state.
- The client’s pain is eliminated or reduced to a tolerable level.
References
- Centers for Disease Control and Prevention. (2022, March). Meningitis | CDC. Centers for Disease Control and Prevention. Retrieved February 5, 2023, from https://www.cdc.gov/meningitis/index.html
- Doenges, M. E., Moorhouse, M. F., & Murr, A. C. (2010). Nursing Care Plans: Guidelines for Individualizing Client Care Across the Life Span. F.A. Davis Company.
- Guo, L. (2020). Seizure Precautions: What Are They, When Are They Used, and More. Osmosis. Retrieved February 5, 2023, from https://www.osmosis.org/answers/seizure-precautions
- Hersi, K., Gonzalez, F. J., & Kondamudi, N. P. (2022, August 14). Meningitis – StatPearls. NCBI. Retrieved February 5, 2023, from https://www.ncbi.nlm.nih.gov/books/NBK459360/
- Leifer, G. (2018). Introduction to Maternity and Pediatric Nursing. Elsevier.
- Mayo Clinic. (2023, January). Meningitis – Symptoms and causes. Mayo Clinic. Retrieved February 5, 2023, from https://www.mayoclinic.org/diseases-conditions/meningitis/symptoms-causes/syc-20350508
- Pillitteri, A., & Silbert-Flagg, J. (2018). Maternal & Child Health Nursing: Care of the Childbearing & Childrearing Family. Wolters Kluwer.
- Vasudeva, S. S., & Stuart, M. (2022, July 11). Meningitis: Practice Essentials, Background, Pathophysiology. Medscape Reference. Retrieved February 5, 2023, from https://emedicine.medscape.com/article/232915-overview#a1
