What is the term used for the condition of having a fever greater than 100.4°F in children?

The term that accurately describes a condition of having a fever greater than 100.4°F in children is pyrexia. This term is specifically used in a medical context to denote an elevated body temperature that often indicates an underlying illness or infection. Pyrexia is not just a simple increase in temperature; it often signifies the body's response to a pathogen, inflammation, or other medical conditions.

Understanding that pyrexia is a symptom, rather than a disease itself, helps to guide further evaluation and treatment of the child’s underlying condition. It is particularly important to assess the context in which the fever occurs, including associated symptoms, duration, and other clinical signs to manage and treat appropriately.

In contrast, hyperthermia refers to an elevated body temperature due to external factors, such as excessive heat exposure, rather than an internal response to illness. Hypothermia is characterized by dangerously low body temperatures. The term febrile response relates to the physiological processes triggered by an infection or inflammation but is not as specific as pyrexia regarding the temperature threshold defined as a fever.