What is considered a prolonged fever?
Prolonged fever, or Fever of Unknown Origin (FUO), is generally defined as a fever that persists beyond 14 days, which distinguishes it from common, self-resolving (often viral) illnesses which may include fever that lasts a week or longer, but generally not as long as two weeks. What are common causes of an FUO? Many different diseases may present as an FUO, including: • Infections – urinary tract, upper respiratory tract, bone and joint, central nervous system, endocarditis • Autoimmune diseases – juvenile rheumatoid arthritis, systemic lupus erythematosis, polyarteritis nodosum, inflammatory bowel disease • Malignancies -leukemia, lymphoma, neuroblastoma • Miscellaneous – factitious fever, drug fever, etc. A significant percentage of cases self-resolve over a period of weeks to months without ever coming to a specific diagnosis. When approaching a child with prolonged fever, it is helpful to remember that the child more often has an occult presentation of a common disease than a tru
