In the E.R., Inouye found her friend already on a gurney in the hallway. Her face was flushed, and her curly auburn hair was matted and dark with sweat. Her eyes, normally clear, were sunken, and the whites strikingly bloodshot. ''It all started about three days ago,'' the patient began. She had felt tired and achy. No appetite. Last night, she had gone to her weekly soccer game thinking that running around might help, but once there, she spent the entire game on the sidelines. ''That's when I knew I was sick. I always want to play - but I just couldn't.'' This morning her fever reached 104 despite as much ibuprofen as her stomach could manage. She had pain in her abdomen on the right and a headache that got worse with every movement.

When the emergency-room doctor came in, Inouye left and the patient began telling her story again, but she withheld one small detail. ''I told him about the fever and the belly pain, but I didn't talk about the headache,'' the patient told me later. ''I tried not to be a doctor- I know we're bad patients -but I worried that if I told anyone how much my head hurt, they'd want to do a lumbar puncture, and I didn't think it was necessary.'' A lumbar puncture, an uncomfortable procedure otherwise known as a spinal tap, would show if the patient had meningitis, and she felt certain she didn't. But leaving out that symptom may have made a difficult diagnosis even harder.

At 48, the patient was healthy and active. Her only visits to the hospital-ever- had been for a variety of broken bones and to deliver her two children. She generally took no medications.