$Unique_ID{BRK00634} $Pretitle{} $Title{Fever Source} $Subject{fever diagnoses Ill Defined Symptoms symptom blood temperature temperatures FUO fevers unknown origin neoplasms neoplasm cancer cancers carcinoma lymphoma leukemia solid tumors infections fungal bacteria rheumatic lupus erythematosus hepatitis gout infection} $Volume{N-7} $Log{} Copyright (c) 1991-92,1993 Tribune Media Services, Inc. Fever Source ------------------------------------------------------------------------------ QUESTION: I had a fever recently, which my doctor diagnosed as being caused by a localized infection. In the course of treating me, he mentioned that it is impossible to successfully uncover the source of a fever. Is he correct? ------------------------------------------------------------------------------ ANSWER: Unfortunately, your doctor is right. While most fevers are either temporary or traceable to a specific ailment, there is a group referred to as FUO--fevers of unknown origin. To be included in this classification, the fever must be present and have eluded normal attempts at diagnosis for at least three weeks. The fever may fall into one of four patterns: a) intermittent; where the temperature returns to a normal level on a daily basis, b) remittent; the fever remains although the temperature subsides to a lower level daily, c) a sustained, consistent fever, and d) a relapsing fever that vanishes for days at a time, only to return. Most of these fevers can eventually be diagnosed, but only with a sustained investment of time and effort on the part of the doctor and increased costs for the patient. The physician first constructs a complete patient history, emphasizing recent travel, new pets or plants, work environment, visits to sick friends or relatives, as well as other factors that can help narrow the range of possible causes. A daily physical exam paying close attention to subtle details (the base of nails, skin condition, mucous membranes, the condition of lymph nodes or hidden rashes) is also a must, together with repeated lab tests on blood, urine or stool samples. Occasionally, x-ray studies, CT scanning, endoscopies or even biopsies may be necessary. In most cases, these procedures will eventually yield definitive answers. Unfortunately, the majority of these fevers are caused by neoplasms--abnormal tissue growth--including lymphoma, leukemia and solid tumors. Infections account for one-third of FUO cases: system-wide infections are most often traced back to fungal bacteria, while localized infections are generally centered in the abdomen. A variety of other diseases account for almost all the remaining fevers, including rheumatic fever, lupus erythematosus, hepatitis and gout. However, some 10% of these mysterious fevers still defy diagnosis, in spite of today's advanced medical knowledge and technology. ---------------- The material contained here is "FOR INFORMATION ONLY" and should not replace the counsel and advice of your personal physician. Promptly consulting your doctor is the best path to a quick and successful resolution of any medical problem.