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(For neonatal meningitis, see Infections in Neonates: Neonatal Meningitis.)

Acute bacterial meningitis is fulminant, often fatal pyogenic infection beginning in the meninges. Symptoms include headache, fever, and stiff neck. Without rapid treatment, obtundation and coma follow. Diagnosis is by CSF tests. Treatment requires antibiotics, often beginning empirically with a 3rd- or 4th-generation cephalosporin, vancomycin, and ampicillin; corticosteroids are usually given. Residual morbidity is common.

Etiology

Many bacteria can cause meningitis, but most common are group B streptococci during the 1st 2 mo of life and, thereafter, Neisseria meningitidis (meningococci) and Streptococcus pneumoniae (pneumococci). Meningococci exist in the nasopharynx of about 5% of people and spread by respiratory droplets and close contact. Only a small fraction of carriers develop meningitis; what makes them susceptible is unknown. Meningococcal meningitis occurs most often in the 1st year of life. It also tends to occur in epidemics among closed populations (eg, in military barracks, college dormitories, boarding schools).

Pneumococci are the most common cause of meningitis in adults. Especially at risk are alcoholics and people with chronic otitis, sinusitis, mastoiditis, CSF leaks, recurrent meningitis, pneumococcal pneumonia, sickle cell disease, or asplenia. Incidence of pneumococcal meningitis is decreasing because of routine vaccination.

Gram-negative meningitis (most often due to Escherichia coli , Klebsiella sp, or Enterobacter sp) can occur in immunocompromised patients or after CNS surgery, CNS trauma, bacteremia (eg, due to GU manipulation), or hospital-acquired infections. Pseudomonas sp occasionally causes meningitis in immunocompromised or colonized patients. Haemophilus influenzae type b meningitis, now uncommon because of widespread vaccination, can occur in immunocompromised patients or after head trauma in unvaccinated people.

Staphylococcal meningitis can occur after penetrating head wounds or neurosurgical procedures (often as part of a mixed infection) or after bacteremia (eg, due to endocarditis). Listerial meningitis can occur at all ages and is particularly common among patients immunocompromised because of chronic renal failure, hepatic disorders, or corticosteroid or cytotoxic therapy after organ transplantation.

Bacteria typically reach the meninges by hematogenous spread from sites of colonization in the nasopharynx or other foci of infection (eg, pneumonia). Why some bacteria are more prone to colonize CSF is not clear, but binding pili and encapsulation appear to play a role. Receptors for pili and other bacterial surface components in the choroid plexus facilitate penetration into CSF.

Bacteria can also enter CSF by direct extension from nearby infections (eg, sinusitis, mastoiditis) or through exterior openings in normally closed CSF pathways (eg, due to meningomyelocele, spinal dermal sinus, penetrating injuries, neurosurgical procedures).

Pathophysiology

Bacterial surface components, complement, and inflammatory cytokines (eg, tumor necrosis factor, IL-1) draw neutrophils into the CSF space. The neutrophils release metabolites that damage cell membranes including those of the vascular endothelium. The result is vasculitis and thrombophlebitis, causing focal ischemia or infarction, and brain edema. Vasculitis also disrupts the blood-brain barrier, further increasing brain edema. The purulent exudate in the CSF blocks CSF reabsorption by the arachnoid villi, causing hydrocephalus. Brain edema and hydrocephalus increase intracranial pressure.

Systemic complications include hyponatremia due to the syndrome of inappropriate antidiuretic hormone (SIADH), disseminated intravascular coagulation (DIC), and septic shock. Occasionally, bilateral adrenal hemorrhagic infarction (Waterhouse-Friderichsen syndrome) results.

Symptoms and Signs

A respiratory illness or sore throat often precedes the more characteristic symptoms of fever, headache, stiff neck, and vomiting. Kernig's and Brudzinski's signs appear in about ½ of patients. Adults may become desperately ill within 24 h, and children even sooner. Seizures occur in about 30%. Cranial nerve abnormalities (eg, 3rd [oculomotor] or 7th [facial] cranial nerve palsy; occasionally, deafness) and other focal deficits occur in 10 to 20%. In patients > 2 yr, changes in consciousness progress through irritability, confusion, drowsiness, stupor, and coma. Opisthotonic posturing may occur.

Dehydration is common, and vascular collapse produces shock. Infection, particularly meningococcal, may be disseminated widely, to the joints, lungs, sinuses, and elsewhere. A petechial or purpuric rash commonly occurs in meningococcal meningitis. Examination of the head, ears, spine, and skin may reveal a source or route of infection. Spinal dimples, sinuses, nevi, or tufts of hair suggest a meningomyelocele.

In children < 2 yr, meningeal signs may be absent. In those < 2 mo, symptoms and signs are often nonspecific, particularly in early disease. Fever, hypothermia, poor feeding, lethargy, vomiting, and irritability are common presenting symptoms. Seizures, a high-pitched cry, and bulging or tight fontanelles are possible but often occur late. Subdural effusions may develop after several days; typical signs are seizures, persistent fever, and enlarging head size.

The elderly may have nonspecific symptoms (eg, confusion with or occasionally without fever). Meningeal signs may be absent or mild. Arthritis may restrict neck motion, often in multiple directions, and should not be mistaken for meningismus.

Partially treated meningitis: Patients seen early in the disease, before typical findings of meningitis appear, are sometimes diagnosed with otitis media or sinusitis and given oral antibiotics. Depending on the drug, the infection may be partially (but temporarily) suppressed. Patients may not appear as ill and have milder meningeal signs and slower disease progression. This situation can significantly hamper recognition of meningitis.

Diagnosis

Acute bacterial meningitis is suspected in children < 2 yr with lethargy, progressive irritability, a high-pitched cry, a bulging fontanelle, meningeal signs, or hypothermia. It is suspected in patients > 2 yr with meningeal signs or unexplained alterations in consciousness, particularly in those with fever or risk factors.

Because acute bacterial meningitis, especially meningococcal, can be lethal within hours, it must be diagnosed and treated rapidly. Prompt lumbar puncture is required but should not delay immediate treatment with antibiotics and corticosteroids.

CSF pressure may be elevated. Gram stain shows organisms in CSF in 80% of patients. CSF neutrophil count usually exceeds 2000/μL. Glucose is usually < 40 mg/dL because of impaired CNS glucose transport and glucose consumption by neutrophils and bacteria. Protein is typically > 100 mg/dL. Cultures are positive in 90%; they may be falsely negative in patients who are partially treated. Latex agglutination tests can be used to detect antigens of meningococci, H. influenzae type b, pneumococci, group B streptococci, and E. coli K1 strains. However, these tests are not always routinely done because they probably add little to other routine CSF tests. The limulus amebocyte lysate test can detect endotoxin in gram-negative meningitis. This test and the latex agglutination tests may be helpful when patients have received prior antibiotics (partial treatment), when patients are immunocompromised, or when other CSF tests do not identify the causative organism. PCR can occasionally be useful if CSF cultures reveal no organisms.

CT may be normal or show small ventricles, effacement of the sulci, and contrast enhancement over the convexities. MRI with gadolinium is more sensitive for subarachnoid inflammation but is not commonly used. Scans should be scrutinized for evidence of brain abscess, sinusitis, mastoiditis, skull fracture, and congenital malformations. Evidence of venous infarctions or communicating hydrocephalus may appear after days or weeks.

Disorders that resemble bacterial meningitis can usually be differentiated by clinical presentation, neuroimaging, and routine CSF tests. Viral meningitis can cause fever, headache, and stiff neck, but patients do not appear as ill and CSF test results are different (see Table 1: Meningitis: Cerebrospinal Fluid Abnormalities in Various Infections). Subarachnoid hemorrhage causes severe headache and a stiff neck, but onset is explosive and fever is usually absent; CT shows hemorrhage, or the CSF contains RBCs or is xanthochromic. Brain abscess can cause fever, headache, and impaired consciousness, but the neck is typically supple unless abscess contents have ruptured into the CSF space, producing a fulminant secondary meningitis. Severe systemic infections (eg, sepsis, infective endocarditis) can impair cognition or consciousness by producing fever and compromising tissue perfusion; CSF is normal or contains a small number of WBCs, and the neck is supple. Cerebellar tonsillar herniation can cause impaired consciousness (secondary to obstructive hydrocephalus) and neck stiffness but usually not fever, and it can be differentiated by CT or MRI. Cerebral vasculitis (eg, due to SLE) and cerebral venous thrombosis can cause mild fever, headache, altered mental status, and mild to moderate meningeal inflammation, typically producing CSF test results similar to those of viral encephalitis.

Occasionally, fungal meningitis or amebic (Naegleria) meningoencephalitis can cause acute, fulminant meningitis with clinical findings and routine CSF test results similar to those of bacterial meningitis. Gram stain and routine cultures show no bacteria. Microscopic examination or culture of CSF can detect fungi (see Meningitis: Diagnosis and Treatment). In amebic meningoencephalitis, ameboid movement can be detected in unspun wet mounts of CSF, and the ameba can be cultured. TB meningitis is usually subacute or chronic but is occasionally acute; CSF characteristics are usually intermediate between those of acute bacterial and aseptic meningitis and special stains (eg, acid-fast, immunofluorescent) are needed to identify TB.

Peripheral blood tests include blood cultures (positive in 50%), cell count with differential, electrolytes, glucose, renal function, and coagulation tests. Serum Na is monitored for evidence of SIADH, and coagulation results are monitored for evidence of DIC. Urine and any nasopharyngeal or respiratory secretions and skin lesions are cultured.

Waterhouse-Friderichsen syndrome should be suspected in any febrile patient who remains in shock despite adequate volume replacement and who has rapidly evolving purpura and evidence of DIC. Serum cortisol level is measured, and CT, MRI, or ultrasonography of the adrenal glands is done.

Prognosis and Treatment

Early antibiotics and supportive care have reduced the mortality rate of acute bacterial meningitis to < 10%. However, if meningitis is treated late or occurs in neonates, the elderly, or immunocompromised patients, death is common. A poor outcome is predicted by persistent leukopenia or development of Waterhouse-Friderichsen syndrome. Survivors occasionally have deafness, other cranial nerve deficits, cerebral infarction, recurrent seizures, or mental retardation.

If acute bacterial meningitis is suspected, antibiotics and corticosteroids are given as soon as blood cultures are drawn (see Table 2: Meningitis: Antibiotic Therapy for Acute Bacterial Meningitis). If the diagnosis is unclear and the patient is not very ill, antibiotics may be withheld pending CSF test results. Giving antibiotics before lumbar puncture slightly increases the probability of false-negative cultures, particularly with pneumococci, but does not affect other test results.

Table 2
Antibiotic Therapy for Acute Bacterial Meningitis Organism Age Group Antibiotic* Comment Unknown Infants < 1 mo Ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph and cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph and gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph ( tobramycin Some Trade Names NEBCIN TOBI TOBREX Click for Drug Monograph or amikacin Some Trade Names AMIKIN Click for Drug Monograph †) see Infections in Neonates: Treatment   Children > 1 mo Ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph and cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ( ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ) and vancomycin Some Trade Names VANCOCIN Click for Drug Monograph —   Adults Ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph and ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) and vancomycin Some Trade Names VANCOCIN Click for Drug Monograph — Gram-positive organisms (unidentified) Children and adults Vancomycin Some Trade Names VANCOCIN Click for Drug Monograph and ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) and ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph ‡ — Gram-negative bacilli (unidentified) Children and adults Ceftazidime Some Trade Names FORTAZ TAZICEF Click for Drug Monograph ( ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph or cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) and gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph ( tobramycin Some Trade Names NEBCIN TOBI TOBREX Click for Drug Monograph or amikacin Some Trade Names AMIKIN Click for Drug Monograph †) — Haemophilus influenzae type b Children and adults Ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) — Meningococci Children and adults Penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph ( ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph ) plus ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) Penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph is used for susceptible strains after sensitivities are known Streptococci (pneumococci) Children and adults Vancomycin Some Trade Names VANCOCIN Click for Drug Monograph and ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) with or without rifampin Some Trade Names RIFADIN RIMACTANE Click for Drug Monograph Penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph may be used for susceptible strains after sensitivities are known Staphylococci Children and adults Vancomycin Some Trade Names VANCOCIN Click for Drug Monograph or nafcillin Some Trade Names UNIPEN Click for Drug Monograph ( oxacillin Some Trade Names BACTOCILL PROSTAPHLIN Click for Drug Monograph ) with or without rifampin Some Trade Names RIFADIN RIMACTANE Click for Drug Monograph Vancomycin Some Trade Names VANCOCIN Click for Drug Monograph is used for methicillin-resistant strains; nafcillin Some Trade Names UNIPEN Click for Drug Monograph or oxacillin Some Trade Names BACTOCILL PROSTAPHLIN Click for Drug Monograph is used for susceptible strains after sensitivities are known. Rifampin Some Trade Names RIFADIN RIMACTANE Click for Drug Monograph is added if no improvement occurs with vancomycin Some Trade Names VANCOCIN Click for Drug Monograph or nafcillin Some Trade Names UNIPEN Click for Drug Monograph Listeria sp Children and adults Ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph ( penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph ) or trimethoprim-sulfamethoxazole Some Trade Names and gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph ( tobramycin Some Trade Names NEBCIN TOBI TOBREX Click for Drug Monograph or amikacin Some Trade Names AMIKIN Click for Drug Monograph †) Penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph is used for susceptible strains after sensitivities are known; trimethoprim-sulfamethoxazole Some Trade Names is used in patients allergic to penicillin Enteric gram-negative bacteria (Escherichia coli, Klebsiella sp, Proteus sp) Children and adults Ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph ( cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph ) and gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph ( tobramycin Some Trade Names NEBCIN TOBI TOBREX Click for Drug Monograph or amikacin Some Trade Names AMIKIN Click for Drug Monograph †) — Pseudomonas sp Children and adults Ceftazidime Some Trade Names FORTAZ TAZICEF Click for Drug Monograph or cefepime Some Trade Names MAXIPIME Click for Drug Monograph (usually alone, can add an aminoglycoside); alternatives: meropenem Some Trade Names MERREM Click for Drug Monograph or aztreonam Some Trade Names AZACTAM Click for Drug Monograph — *Alternative antibiotics are in parentheses. Among 3rd-generation cephalosporins, cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph may be preferred for children; ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph , for adults. † Amikacin Some Trade Names AMIKIN Click for Drug Monograph is used in areas where gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph resistance is common. Because aminoglycosides have poor CSF penetration, they may have to be given intrathecally or via an Ommaya reservoir, especially in patients with Pseudomonas meningitis. When aminoglycosides are used, renal function should be monitored. ‡If the gram-positive organisms are pleomorphic, ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph is included to cover Listeria sp.

Dexamethasone Some Trade Names
DECADRON
DEXASONE
HEXADROL
Click for Drug Monograph
0.15 mg/kg IV q 6 h in children and 10 mg IV q 6 h in adults should be given 15 min before the 1st dose of antibiotics and continued for 4 days. Dexamethasone Some Trade Names
DECADRON
DEXASONE
HEXADROL
Click for Drug Monograph
may prevent hearing loss and other neurologic sequelae, possibly by inhibiting release of proinflammatory cytokines triggered by antibiotic-induced bacterial lysis. Dexamethasone Some Trade Names
DECADRON
DEXASONE
HEXADROL
Click for Drug Monograph
should not be given to patients with immunodeficiency because it may impair host defenses against nonbacterial meningitis.

If no pathogen is identified in the CSF, addition of antibiotics for TB should be considered. If no bacteria grow in culture or are otherwise identified after 24 to 48 h, corticosteroids are stopped; corticosteroids continued for > 1 day without appropriate antibiotic coverage could worsen the infection. Corticosteroids impede vancomycin Some Trade Names
VANCOCIN
Click for Drug Monograph
's penetration of CSF, so the vancomycin Some Trade Names
VANCOCIN
Click for Drug Monograph
dose may have to be increased.

When initial CSF tests are inconclusive, a repeat lumbar puncture in 8 to 24 h (or sooner if the patient deteriorates) may help. If clinical and CSF findings continue to suggest aseptic meningitis, antibiotics are withheld. If the patient's condition is serious, especially if antibiotics have been given (possibly producing falsely sterile cultures), antibiotics should be continued.

Choice of antibiotics depends on pathogen and patient age (see Table 2: Meningitis: Antibiotic Therapy for Acute Bacterial Meningitis; for antibiotic doses, see Table 3: Meningitis: Common IV Antibiotic Dosages for Bacterial Meningitis*). Third-generation cephalosporins (eg, ceftriaxone Some Trade Names
ROCEPHIN
Click for Drug Monograph
, cefotaxime Some Trade Names
CLAFORAN
Click for Drug Monograph
) are effective against pathogens common in patients of all ages. Cefepime Some Trade Names
MAXIPIME
Click for Drug Monograph
, a 4th-generation cephalosporin, can be substituted for a 3rd-generation cephalosporin in children and can be useful for Pseudomonas infection. However, because cephalosporin-resistant pneumococci are becoming increasingly prevalent, vancomycin Some Trade Names
VANCOCIN
Click for Drug Monograph
, with or without rifampin Some Trade Names
RIFADIN
RIMACTANE
Click for Drug Monograph
, is usually added. Ampicillin Some Trade Names
OMNIPEN
PRINCIPEN
Click for Drug Monograph
is added to cover Listeria sp. Aminoglycosides penetrate the CNS poorly but are still used empirically to cover gram-negative bacteria in neonates (see Infections in Neonates: Treatment). When CSF Gram stain and culture results become available, antibiotics are adjusted.

Table 3
Common IV Antibiotic Dosages for Bacterial Meningitis* Dosage Antibiotic Children > 1 mo Adults Ceftriaxone Some Trade Names ROCEPHIN Click for Drug Monograph 50 mg/kg q 12 h 2 g q 12 h Cefotaxime Some Trade Names CLAFORAN Click for Drug Monograph 50 mg/kg q 6 h 2 g q 4–6 h Ceftazidime Some Trade Names FORTAZ TAZICEF Click for Drug Monograph 50 mg/kg q 8 h 2 g q 8 h Cefepime Some Trade Names MAXIPIME Click for Drug Monograph 2 g q 12 h 2 g q 8–12 h Ampicillin Some Trade Names OMNIPEN PRINCIPEN Click for Drug Monograph 75 mg/kg q 6 h 2–3 g q 4 h Penicillin G Some Trade Names BICILLIN WYCILLIN Click for Drug Monograph 4 million units q 4 h 4 million units q 4 h Nafcillin Some Trade Names UNIPEN Click for Drug Monograph and oxacillin Some Trade Names BACTOCILL PROSTAPHLIN Click for Drug Monograph 50 mg/kg q 6 h 2 g q 4 h Vancomycin Some Trade Names VANCOCIN Click for Drug Monograph † 15 mg/kg q 6 h 500–750 mg q 6 h Gentamicin Some Trade Names GARAMYCIN Click for Drug Monograph and tobramycin Some Trade Names NEBCIN TOBI TOBREX Click for Drug Monograph † 2.5 mg/kg q 8 h 2 mg/kg q 8 h Amikacin Some Trade Names AMIKIN Click for Drug Monograph † 10 mg/kg q 8 h 7.5 mg/kg q 12 h Rifampin Some Trade Names RIFADIN RIMACTANE Click for Drug Monograph 6.7 mg/kg q 8 h 600 mg q 24 h Chloramphenicol Some Trade Names CHLOROMYCETIN Click for Drug Monograph 25 mg/kg q 6 h 1 g q 6 h *see Table 1: Infections in Neonates: Recommended Dosages of Selected Parenteral Antibiotics for Neonates for neonatal dosages. †Renal function should be monitored.

Lumbar puncture should be repeated 24 to 48 h after starting antibiotics to confirm CSF sterility and conversion to lymphocytic predominance. Generally, antibiotics are continued for ≥ 1 wk after fever subsides and CSF is nearly normal (complete normalization may take weeks). Drug doses are not reduced when clinical improvement occurs because drug penetration commonly decreases as meningeal inflammation decreases.

Supportive therapy includes treatment of fever, dehydration, electrolyte disorders, seizures, and shock. If Waterhouse-Friderichsen syndrome is suspected, high-dose hydrocortisone Some Trade Names
CORTEF
SOLU-CORTEF
Click for Drug Monograph
(eg, 100 to 200 mg IV q 4 to 6 h or as a continuous infusion after an initial bolus) is given; treatment should not be delayed pending hormone levels.

Cerebral edema can be minimized by avoiding overhydration. If brain herniation is suspected, hyperventilation (Paco₂, 25 to 30 mm Hg), mannitol Some Trade Names
OSMITROL
RESECTISOL
Click for Drug Monograph
(0.25 to 1.0 g/kg IV), and additional dexamethasone Some Trade Names
DECADRON
DEXASONE
HEXADROL
Click for Drug Monograph
(4 mg IV q 4 h) can be used; monitoring intracranial pressure may be helpful. If ventricles are enlarged, intracranial pressure may be monitored and CSF drained, but outcome is usually poor.

For infants up to 1 yr of age with subdural effusion, daily subdural taps through the cranial sutures usually help. No more than 20 mL/day of CSF should be removed from one side to avoid sudden shifts in intracranial contents. If effusion persists after 3 to 4 wk of taps, surgical exploration for possible excision of a subdural membrane is indicated.

Patients with severe meningococcal meningitis may benefit from drotrecogin alfa Some Trade Names
XIGRIS
Click for Drug Monograph
(activated protein C), which downregulates the inflammatory response. A greater frequency of intracranial bleeding occurs with or without drotrecogin alfa Some Trade Names
XIGRIS
Click for Drug Monograph
treatment in patients septic due to meningitis.

Prevention

A conjugated pneumococcal vaccine effective against 7 serotypes, including > 80% of organisms that cause meningitis, is recommended for all children (see Immunization: Pneumococcal Disease; see Fig. 3: Approach to the Care of Normal Infants and Children: Recommended childhood and adolescence immunization schedule.). Routine vaccination for H. influenzae type b is highly effective and begins at age 2 mo. A quadrivalent meningococcal vaccine is given to children ≥ 2 yr with immunodeficiencies or functional asplenia, travelers to endemic areas, and laboratory personnel who routinely handle meningococcal specimens. Meningococcal vaccine should also be considered for students living in dormitories and for military recruits.

Spread of meningitis is prevented by keeping patients in respiratory isolation (droplet precautions) for the 1st 24 h of therapy. Gloves, masks, and gowns are used. Anyone who has face-to-face contact with the patient (eg, family and medical staff members) should receive postexposure prophylaxis. For meningococcal meningitis, it consists of meningococcal vaccine and chemoprophylaxis. Vaccination is especially important for containing epidemics. Chemoprophylaxis against meningococci is oral rifampin Some Trade Names
RIFADIN
RIMACTANE
Click for Drug Monograph
for 48 h (adults, 600 mg q 12 h; children, 10 mg/kg q 12 h; infants < 1 mo, 5 mg/kg q 12 h). Alternatives include a single dose of IM ceftriaxone Some Trade Names
ROCEPHIN
Click for Drug Monograph
(adults, 250 mg; children, 125 mg) or a single dose of ciprofloxacin Some Trade Names
CILOXAN
CIPRO
Click for Drug Monograph
500 mg po (adults only). Chemoprophylaxis against H. influenzae type b is rifampin Some Trade Names
RIFADIN
RIMACTANE
Click for Drug Monograph
20 mg/kg po once/day (maximum 600 mg) for 4 days. There is no consensus on whether children < 2 yr require prophylaxis for exposure at day care. Chemoprophylaxis is not usually needed for contacts of patients with pneumococcal meningitis.

Last full review/revision November 2005

Content last modified November 2005