If bacterial meningitis is suspected several tests sound be done before beginning treatment. A blood sample should be taken and a complete blood count (CBC) should be performed and a lumbar puncture should also be performed as soon as possible. Laboratory findings The white blood cell count (WBC) should be 5,000-10,000 /mm3. Critical values associated WBC are 30,000 /mm3. Variables that may increase white blood cell count include: Physical activity and stress, final months of pregnancy and/or labor and patients who have had a splenectomy.
Drugs that may increase white blood cell count include: adrenaline, allopurinol, aspirin, chloroform, epinephrine, heparin, quinine, steroids, and triamterene. Inversely drugs that may cause decreased WBC levels include antibiotics, anticonvulsants, antihistamines, antimetabolites, antithyroid drugs, arsenicals, barbiturates, chemotherapeutic agents, diuretics, and sulfonamides. Differential values should be as follows: neutrophils 55-70%, lymphocytes 20-40%, monocytes 2-8%, eosinophils 1-4%, basophils 0. 5-1%. The platelet count should be 150,000-400,000 /mm3.
Factors that affect normal value ranges for differential values are similar to those that affect white blood cell count. Glucose and sodium levels should also be monitored. Normal values for glucose are 74-106 mg/dL (critical value 400 mg/dL) and normal values for sodium are 136- 145mEq/L (critical values 160 mEq/L). Factors affecting normal sodium values include: high dietary salt intake or abnormal kidney function. Drugs that may increase normal levels include: antibiotics, cough medicines, laxatives, and steroids.
Drugs that may decrease normal sodium levels include diuretics and steroids In general the WBC is elevated and the differentials are shifted to the left. However, a patient might have a depressed WBC if they are immunocompromised, very young or very old. A lumbar puncture will also be necessary for analysis of cerebrospinal fluid (CSF) for blood-glucose ratio, WBC count, lactate level, protein concentration. Normal blood glucose values, as mentioned above, are 74-106mg/dL. Possible critical values for males are 400mg/dL. Critical values for females are 400mg/dL.
Factors that can effect normal levels include: Many forms of stress can cause increased serum glucose levels, pregnant women experiencing gestational diabetes, patients on IV solutions containing dextrose. Drugs that increase levels include: tricyclic antidepressants, antipsychotics, beta-adrenergic blocking agents, corticosteroids, cyclosporine, dextrothyroxine, diazoxide, diuretics, epinephrine, estrogens, glucagon, isoniazid, lithium, niacin, phenothiazines and phenytoin. Lactate levels for venous blood is 5-20 mg/dL and lactate levels for arterial blood is 3-7 mg/dL.
Using a tourniquet or cleaning of hands can increase lactate levels as can drugs such as aspirin, cyanide, chronic ethanol use, nalidixic acid, and phenformin. Gram stain and culture could provide a more rapid result than cerebrospinal fluid analysis which could take up to 48 hours. Getting a result quickly is very important in bacterial meningitis cases. While gram staining is the traditional choice it might not be the best option in every case as gram staining can be prone to operator error and a negative gram stain does not rule out infection.
There are a few alternatives such as The KOH String Test, aminopeptidase test, fluorescent stain, and LAL-based assay. Also, there are several different strains of bacteria that can cause meningitis including Streptococcus pneumoniae, group B Streptococcus, Neisseria meningitidis, Haemophilus influenzae, and Listeria monocytogenes. Depending on which strain of bacteria is the cause it will vary the treatment options. Treatment Once a diagnosis of bacterial meningitis has been confirmed there are several options for treatment options. The correct treatment varies based on age and some predisposing features.
All therapies are antibiotic treatments because this is a very serious disease and treatment should begin immediately. Treatments for relief of symptoms can include non-steroidal anti-inflammatory drugs and anti-convulsant agents but it should be noted that the therapies will not cure the infection and antibiotics should always be the foundation of bacterial meningitis treatment. Antibiotic treatment would be the most effective at resolving the infection. Based on the patients age, if the they are between 0-4 weeks old the recommended treatment would be ampicillin plus either aminoglycoside or cefotaxime.
If the patient is between 1 month-50 years old a treatment of Vancomycin plus cefotaxime or ceftriaxone. If the patient is greater than 50 years of age a treatment of vancomycin plus ampicillin plus ceftriaxone or cefotaxime plus vancomycin is recommended. Predisposing features and treatments can include impaired cellular immunity for which the treatment would consist of vancomycin, ampicillin, and either cefepime or meropenem. For a case of recurrent meningitis the recommended treatment is vancomycin and either cefotaxime or ceftriaxone.
In the case of a basilar skull fracture treatment would include vancomycin and cefotaxime or ceftriaxone. For cases of head trauma, neurosurgery, or CSF shunt recommended treatment is vancomycin and either ceftazidime, cefepime, or meropenem. The length of antibiotic treatment is determined by the specific strain of bacteria causing the infection. The length of treatment based on strain is as follows; Pneumococcus 10 to 14 days, meningococcus 5 to 7 days, haemophilus influenzae type b 7 to 14 days, listeria 21 days, gram-negative bacilli and Pseudomonas 21 to 28 days, and if the bacteria is unspecified treatment should last 10 to 14 days.
Some of the antibiotics dosages are as follows: Ceftriaxone Sodium 4 g/day IV in divided doses every 12 to 24 hours for 7 days for adults and 80 to 100 mg/kg/day IV in divided doses every 12 to 24 hours for 7 days for pediatrics, Cefotaxime Sodium 8 to 12 g/day IV in divided doses every 4 to 6 hours for 7 days for adults and 225 to 300 mg/kg/day IV in divided doses every 6 to 8 hours for 7 days for pediatrics, Penicillin G Potassium 24 million units/day IV in divided doses every 4 hours for 7 days for adults and 0. million units/kg/day IV in divided doses every 4 to 6 hours for 7 days for pediatrics, Ampicillin 12 g/day IV in divided doses every 4 hours for 7 days for adults and 300 mg/kg/day IV in divided doses every 6 hours for 7 days for pediatrics, Meropenem 6 g/day IV in divided doses every 8 hours for 7 days for adults, Dexamethasone 0. 15 mg/kg IV every 6 hours for 2 to 4 days; administer 10 to 20 minutes before or concurrently with first antibiotic dose; do not administer if antibiotics have already been given for adults and 0. 5 mg/kg IV every 6 hours for 2 to 4 days; administer 10 to 20 minutes before or concurrently with first antibiotic dose; do not administer if antibiotics have already been given for pediatrics.
Antibiotic side effects vary from patient to patient and can be mild to severe if the patient is allergic to a particular antibiotic treatment. The most common adverse effects reported are nausea, vomiting, diarrhea and rash. If the patient is allergic much more severe side effects can be seen including throat tightness, dizziness and anaphylaxis.
These symptoms should be considered an emergency and should be treated immediately. Alternative treatments There are not any alternative treatments or non-pharmacological treatments for bacterial meningitis. This is a life-threatening condition and can only be treated with antibiotic therapy. There are options to treat the symptoms of bacterial meningitis but those will not fix the actual infection and could cause a patient to avoid antibiotic treatment because they think the infection is being cleared up due the disappearance of symptoms.
Non-steroidal anti-inflammatory drugs (NSAIDs) can be used to treat the symptoms caused by bacterial meningitis and include Acetaminophen dosed at 650 to 1000 mg for adults, orally every 4 to 6 hours as needed; maximum 4 g/day, 10 to 15 mg/kg for pediatrics orally or rectally every 4 to 6 hours as needed; maximum 5 doses or 4 g/day and 10 to 15 mg/kg for neonates orally or rectally every 6 to 8 hours as needed. Aspirin can be dosed at 650 to 1000 mg for adults orally every 4 hours as needed; maximum 4 g/day. Ibuprofen can be doses at 200 to 800 mg for adults orally every 6 to 8 hours as needed; maximum 3. g/day and 5 to 10 mg/kg for pediatrics orally every 6 to 8 hours as needed; maximum, lesser of 40 mg/kg/day or 2. 4 g/day The most common NSAID side effects include stomach pain and ulcer, and dizziness.
Chronic use of NSAIDs can cause impaired renal or hepatic function and hypertension. NSAIDs can also cause an increased risk of bleeding and should be avoided in patients taking blood-thinning medications such as warfarin. Drugs to treat seizures can be used as secondary treatment as well and include Diazepam, Lorazepam, Fosphenytoin Sodium, and Phenobarbital Sodium.
Dosages should be determined on a case-by-case basis and could require adjustment. Adverse effects for anticonvulsant medications include: leukopenia, nausea, vomiting, headache, hyponatremia, jaundice, apnea, respiratory depression, catatonia, delirium, depression, hallucinations, psychotic disorder, suicidal thoughts. Anticonvulsants shouldn’t be used with children or older adults and while taking anticonvulsant medication patients should avoid alcohol, anti-depressants, and other sedative medications.
