Bacterial meningitis, an inflammation of the membranes that protect the covering of the brain and spinal cord, kills tens of thousands worldwide every year and requires antibiotic therapy for cure and survival. Symptoms can include a stiff neck, fever, headache, vomiting, and altered mental status.
While the spinal fluid and blood cultures ordered by emergency physicians can identify the more serious bacterial form of meningitis, the majority of the patients will have one of the non-bacterial forms that do not require antibiotic treatment.
The researchers report in the December issue of the Mayo Clinic Proceedings that they have identified a possible way to help physicians determine which patients with meningitis are at risk of a serious outcome.
Dr. Rodrigo Hasbun, the study’s senior author and associate professor of internal medicine, and his colleagues conducted a statistical analysis of 567 patients who were treated for meningitis at eight hospitals in the Memorial Hermann Healthcare System between 2005 and 2010 and identified independent variables associated with those who either developed a disability or died.
Researchers divided patients into two groups. The initial statistical analysis was conducted on the records of 292 patients. Findings were later validated in the remaining 275 patients.
“The majority of patients did not have a cause for their meningitis identified, and only 4 percent had bacterial meningitis. Sixty patients had an adverse clinical outcome,” Hasbun said.
The factors associated with a bad outcome include an age greater than 60, a cerebrospinal glucose level of less than 45 mg/dL, and neurological abnormalities, including seizures and altered mental status.
“These are three easily obtainable variables that doctors can check to determine how likely the patient is to die or develop a disability,” Hasbun said.
While there are tests to determine the causes of non-bacterial meningitis, these tests may not be available to a physician who has to decide on a treatment plan. Some patients may have a bacterial infection that has yet to show up in their blood or spinal fluid cultures.
“These are red flags that doctors can look for,” said Hasbun, who described the factors as a risk score.
“If the patient has none of these factors, the patient’s chance of having an adverse clinical outcome is less than 1 percent. Conversely, if the patient has any of these factors, the patent’s chance of having an adverse clinical outcome is about one in three,” he explained.
Hasbun said the study was one of the largest ever conducted involving adult meningitis patients in the United States, but that additional studies are needed to confirm the findings.
Other contributors to UTHealth include: Dr. Nabil Khoury, lead author and former UTHealth infectious diseases fellow; Dr. Monir Hossain; Dr. Susan Wootton; and Dr. Lucrecia Salazar.
The study titled, “Meningitis With a Negative Cerebrospinal Fluid Gram Stain in Adults: Risk Classification for an Adverse Clinical Outcome,” received support from the Center for Clinical and Translational Sciences at UTHealth, the Grant-A Starr Foundation and the National Center for Research Resources.
The project described was supported by Award Number K23RR018929 from the National Center for Research Resources. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health.
-Rob Cahill, Office of Advancement, Media Relations