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DIFFICULTIES IN DIAGNOSIS AND TREATMENT such cases, we need to clarify if there is a medical
OF INFECTIOUS MENINGITIS history of systemic lupus erythematosus, sarcoidosis,
or rheumatoid arthritis; order the appropriate laboratory
The BBB protects the brain tissue, but is also the greatest investigations; and request a rheumatology consultation.
obstacle to treatment of infectious meningitis. The focus Tumor-related meningitis (immunity meningitis or
is often on the effective permeation rate of treatment cancerous meningeal disease) can present with fever
drugs across the BBB, instead of the sensitivity of the or other symptoms of meningitis. Detection of tumor
drug, which can influence the efficacy of treatment. [5] markers in blood and CSF, cytology testing of CSF, and
scans (computed tomography, magnetic resonance
High doses and a long treatment course are needed imaging [MRI], and positron emission tomography) can
for therapy of infectious meningitis. For example, an be helpful in the differential diagnosis.
intensive course of treatment for tubercular meningitis
requires a dose of isoniazid of 15 mg/kg per day, Differential diagnosis of possible infectious meningitis
whereas the general dose in instruction is 0.6 g/day. pathogens
The treatment course for intracranial tuberculosis Pathogens causing infectious meningitis include
is double that for extracranial tuberculosis, that is, bacteria, fungi, and viruses. It is important to distinguish
4–6 months of intensive treatment and 18–24 months for the species of pathogens with no result of CSF smear.
[6]
the whole course. Such doses and treatment courses Purulent meningitis is easier to identify by observing the
pose challenges for both doctors and patients. CSF appearance, CSF cell number, and the percentage
of multinucleate cells.
Because of the problems of pathogen isolation and
difficulty in permeating the BBB, doctors need to Viral, tuberculous, and C. neoformans meningitis
perform experimental therapies and choose drugs that are more difficult to distinguish. The disease course
can effectively cross the BBB. That means doctors have for tuberculous and C. neoformans meningitis is
to break the usage principle of antibiotics or the medical over 6 weeks, and may be as long as several months,
insurance regulations. This is also a great challenge. but that for viral meningitis is often less than 3 weeks.
The body temperature of a patient with viral or
From the three points above, we can see that the risk C. neoformans meningitis can be over 39°C, but a
of treatment failure in infectious meningitis is higher patient with tuberculous meningitis often has fever in
than in other infectious diseases. Doctors are extremely the afternoon and the body temperature is below 39°C.
concerned about the risk in specific countries and
regions (tense physician – patient relationship) or of With regard to CSF examination, the differences
legal action. between the various meningitis types are as follows:
(1) pressure: in C. neoformans meningitis, pressure
DIAGNOSIS AND TREATMENT OF MENINGITIS is above 300 mmH O; in tuberculous meningitis, it is
2
more often between 250 and 280 mmH O (rarely above
2
Differential diagnosis of infectious and noninfectious 300 mmH O unless there is meninges adhesion); and
2
meningitis in viral meningitis, it is normal or a little higher, rarely
A patient presenting with fever, headache, nausea, above 250 mmH O. (2) Glucose and chloride levels:
[7]
2
emesis, meningeal irritation, and abnormal CSF in tuberculous meningitis, these are both decreased
findings (high pressure, increased white cell count, or at least glucose is decreased, sometimes below
and decreased glucose and chloride levels) is easily 1.0 mmol/L; in viral and C. neoformans meningitis,
misdiagnosed as having meningitis. However, it is glucose is decreased or normal, often between 2.0 and
necessary to exclude noninfectious causes of meningitis 2.8 mmol/L, while chloride is generally normal, or
such as chemicals, connective tissue diseases, and if decreased, is often between 110 and 118 mmol/L.
tumors. A patient with chemical meningitis usually has (3) Protein levels: in tuberculous meningitis, protein
a clear history of intrathecal medicine injection such is obviously increased at between 1.0 and 2.0 g/L,
[8]
as cytarabine, methotrexate, or analgesics. Because and may be over 10 g/L, but in viral and C. neoformans
chemical meningitis often occurs during a period of meningitis, it is rarely more than 1.0 g/L.
hospitalization or in patients with a clear history of using
specific medicines, it is easier to exclude. Connective Using MRI with enhancement, we can see that the
tissue disease-related meningitis is often ignored. In strengthened signals in the meninges are strongest for

4 Neuroimmunol Neuroinflammation | Volume 1 | Issue 1 | June 2014