Types of fever...Really!

Performance of the various types of fever
a) Fever continues
b) Fever continues to abrupt onset and remission
c) Fever remittent
d) Intermittent fever
e) Undulant fever
f) Relapsing fever

The pattern of temperature and diagnosis:

• Continuous fever: Temperature remains above normal throughout the day and does not fluctuate more than 1 °C in 24 hours, e.g. lobar pneumonia, typhoid, urinary tract infection, brucellosis, ortyphus. Typhoid fever may show a specific fever pattern (Wunderlich curve of typhoid fever), with a slow stepwise increase and a high plateau. (Drops due to fever-reducing drugs are excluded.)
• Intermittent fever: The temperature elevation is present only for a certain period, later cycling back to normal, e.g. malaria, kala-azar, pyaemia, or septicemia. Following are its types 
  • Quotidian fever, with a periodicity of 24 hours, typical of Plasmodium falciparum
  • Tertian fever (48 hour periodicity), typical of Plasmodium vivax and Plasmodium ovale
  • Quartan fever (72 hour periodicity), typical of Plasmodium malariae.
• Remittent fever: Temperature remains above normal throughout the day and fluctuates more than 1 °C in 24 hours, e.g., infective endocarditis.
• Pel-Ebstein fever: A specific kind of fever associated with Hodgkin's lymphoma, being high for one week and low for the next week and so on. However, there is some debate as to whether this pattern truly exists.

A neutropenic fever, also called febrile neutropenia, is a fever in the absence of normal immune system function. Because of the lack of infection-fighting neutrophils, a bacterial infection can spread rapidly; this fever is, therefore, usually considered to require urgent medical attention. This kind of fever is more commonly seen in people receiving immune-suppressing chemotherapy than in apparently healthy people.

Febricula is an old term for a low-grade fever, especially if the cause is unknown, no other symptoms are present, and the patient recovers fully in less than a week.