(NEW YORK) -- Jim McGuire said he was relieved when doctors told him his spinal tap tested negative for fungal meningitis last week, but his feeling of panic returned the next day when a severe headache set in.
Although the headache could have been a result of his spinal tap, McGuire's doctor told him there was a chance he was experiencing the onset of meningitis -- even though he had tested negative the day before.
"It felt like there was a knife sticking in your head," McGuire, 51, said. "I've had sinus headaches, which are more of a dull ache. This was a very sharp pain that was constant."
And McGuire is not alone in wondering whether he is having a spinal headache or meningitis. A spinal tap is the only way to tell if a patient has meningitis, and 40 percent of spinal tap patients get spinal headaches as a result, according to the Mayo Clinic.
More than 14,000 patients nationwide may have been exposed to fungal meningitis if they received contaminated compounded steroid injections manufactured by New England Compounding Co. in Massachusetts. Of the 212 people who were infected, 15 have died, the Centers for Disease Control and Prevention said on Monday. Another two patients developed joint infections.
McGuire spent eight hours in the hospital last Monday after he learned that he received a contaminated epidural injection for his back pain in August. He was among about 300 patients to receive a spinal tap at Saint Thomas Hospital in Nashville, Tenn., because of the fungal meningitis outbreak, said hospital spokeswoman Rebecca Climer.
He then had to miss two and a half days of work, lying down at home with the drapes closed because his head hurt, he said.
If McGuire had a spinal headache, it would mean that spinal fluid leaked from the puncture where doctors performed his spinal tap, offsetting the normal pressure from fluid in the spinal column, said Dr. Joshua Bederson, who chairs neurosurgery at Mount Sinai Hospital in New York.
The brain produces and absorbs four cups of spinal fluid each day, he said. When there's too little fluid, as in a spinal headache, the brain sags in the skull, pulling on veins that connect the outer surface of the brain to the inner surface of the skull. That's what causes the intense headache. It usually clears up on its own without major health complications.
Meningitis headaches, on the other hand, are caused by inflammation of the membranes in the brain and spine. They can result in permanent neurological damage and death.
But which is which?
If the headache is positional, it's probably a spinal headache, Bederson said. The patient should get relief from lying down, but feel more pain when he or she stands up.
If the pain is constant and not positional, it may be something else.
Copyright 2012 ABC News Radio