A lumbar puncture (LP) for CSF analysis (cell count, glucose and protein levels, microbiological culture and molecular detection of bacterial DNA [if clinical suspicion is high and bacterial cultures are negative] and viral studies where appropriate, as well as consideration for specific testing for tuberculosis in high-risk children) is indispensable for the definitive diagnosis of meningitis. An LP should always be attempted unless there are contraindications. Molecular diagnostics may still be useful even if antimicrobials have been administered, and available options should be discussed with a microbiologist. Contraindications to LP include coagulopathy, cutaneous lesions at the proposed puncture site, signs of herniation or an unstable clinical status such as shock. If there is papilledema, the presence of focal neurological signs, decreased level of consciousness or coma, an LP should be deferred until imaging (a contrast-enhanced computed tomography and/or magnetic resonance imaging of the head) is performed and the risk of potential herniation is ruled out. Although there are no specific studies involving children, herniation following an LP in meningitis is rare in the absence of focal CNS lesions.  
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. There are numerous cases of nausea and vomiting. Some causes may not require medical treatment, for example, motion sickness, and other causes may require medical treatment by a doctor, for example, heart attack, lung infections, bronchitis, and pneumonia.
Some causes of nausea and vomiting may be life threatening, for example, heart attack, abdominal obstruction, and cancers.
Treatment of nausea and vomiting depends upon the cause.
Q. What Causes Meningitis? I was told that meningitis is a very infectious disese. What causes meningitis? A. Most cases of meningitis are caused by microorganisms, such as viruses, bacteria, fungi, or parasites, that spread into the blood and into the cerebrospinal fluid (CSF). Non-infectious causes include cancers, certain drugs and more. The most common cause of meningitis is viral, that is usually less severe. Bacterial meningitis is the second most frequent type and can be serious and life-threatening. Bacterial meningitis is a medical emergency.