118 Fever

Question 1

Feature of an Intermittent Fever

Answer 1

Temperature returns to normal at least once every 24 hours.

Question 2

Feature of Remittent Fever

Answer 2

Temperature does not return to normal but does vary a few degrees in either direction

Question 3

Feature of Sustained Fever

Answer 3

Temperature remains above normal with only minimal variation

Question 4

Feature of Relapsing Fever

Answer 4

A fever where there is one or more episodes of fever lasting as long as several days with one or more days of normal temperature between episodes

Question 5

What is the relation between HR and Temperature?

Answer 5

1 Degree raise in temperature = 15bpm increase in HR

Question 6

What is fever?

Answer 6

Fever is an elevation of body temperature above the normal range of 36.5 to 37.5 due to an increase in set point

Question 7

What region of the brain regulates core body temperature?

Answer 7

The Hypothalamus

Question 8

What are the 4 stages of a fever?

Answer 8

First/Prodromal
Second/Chill Phase
Third/Flush
Fourth/Defervescence

Question 9

Characteristics of the First/Prodromal Phase?

Answer 9

Non-specific complaints such as headache, fatigue, malaise and aching

Question 10

Characteristics of the Second/Chill Phase?

Answer 10

Sensation of being chilled
Onset of Shaking
Vasoconstriction and piloerection
When body temp reaches new set point, feeling of warmth develops

Question 11

Characteristics of Third/Flush Phase?

Answer 11

Cutaneous vasodilation occurs and the skin becomes warm and flushed leading to the last phase

Question 12

Characteristics of the Fourth/Defervescent Phase?

Answer 12

Initiation of sweating

Question 13

Symptoms of Fever?

Answer 13

Feeling hot
Rigors - Shivering due to muscle activity (UTI)
Excessive sweating (Night sweats typical of TB and Lymphomas)
Delirium - Mental confusion especially in elderly and young children
Muscle pain - Myalgia and Arthralgia characteristic of viral infections and septicaemia illnesses

Question 14

What is the average normal core temperature?

Answer 14

37.1 degrees

Question 15

What is a Pyrogen?

Answer 15

A Pyrogen is a substance that causes fever.

They can be either Endogenous (Internal) or Exogenous (External)

Question 16

What is the main Endogenous Pyrogen?

Answer 16

IL-6

Question 17

Give some examples of Endogenous Pyrogens?

Answer 17

IL-1, IL-6, TNF-a, Interferon (INF)

Question 18

What is IL-10

Answer 18

An antipyretic factor that limit febrile respond by competing with IL-6

Question 19

What is the main Exogenous Pyrogen?

Answer 19

Lipopolysaccharide (LPS)

Question 20

What are Acute Phase Proteins

Answer 20

Factors produced by the Liver to provide functions for the immune system

Question 21

Give an example of a positive Acute Phase Protein?

Answer 21

C-Reactive Protein (CRP)

Stimulates Opsonin which activated the complement system

Question 22

What is the difference between Fever and Hyperthermia?

Answer 22

Hyperthermia is the pathological increase in body temperature WITHOUT a change in set point within the Hypothalamus

Question 23

What is Pyrexia of Unknown Origin

Answer 23

Consistently elevated body temperature of more than 38.3 persisting for 3 weeks with no diagnosis after initial investigations either after 3 days as an impatient or 3 outpatient consultations.

Question 24

Give examples of common causes of Pyrexia?

Answer 24

Infection - Sepsis, Endocarditis, TB, HIV
Malignancy - Lymphoma, Melanoma, Leukaemia
Connective Tissue Disorders - RA, Lupus Erythromatosis, Rheumatic Fever
Miscellaneous - IBD, Drug Reaction, Sarcoidosis, DVT/PE