L25 Boy w a Fever ILA Flashcards
Define fever and the normal human temperature - what factors cause variation
A state of elevated core temperature which is part of defensive response to invasion of matter recognized as pathogenic.
NHT: 35.6- 38.2 (mean 36.8).
Woman hotter than men. Body temperature varies throughout the day - coldest in morning.
What are the factors that influence body heat : production, distribution, regulation
Metabolism produces heat.
It is distributed by the circulatory system - cutaneous blood flow.
Is regulated by thermoregulators in the hypothalamus, core and cutaneous thermosensors
How does fever come about and why do we have fever
- PAMPs stimulate the immune system—>
macrophages, causing it to release IL6 or other analogues.
2.Once concentrations have reached a threshold, it binds to receptors in the hypothalamus which initiate the fever response
- Fibres from hypothalamus to the cerebral cortex elicits other features of illness
- loss of appetite, lethargy, sense of doom,
Purpose:
- increasing the temperature can reduce rates of virus replication (eg. rhinoviruses)
- immune cells eg. neutrophils function better in higher temperatures - production of oxidative species when killing bacteria.
However ROS are dangerous so good to be highly functional when needed, not all the time
What is the most common serious illness in primary care
: infection of limbs, pyelonephritis, pneumonia or meningitis
Pneumonia is much more common than meningitis, infection of the limbs and pyelonephritis (which increases with age, but still small)
What is the best predictive tool for serious bacterial infection
Experienced GP that is worried
What 4 bacteria causes meningitis
- Streptococcus pneumoniae
- Neisseria meningitidis
- Haemophilus influenzae
- Listeria monocytogenes
Is fever valid if it hasn’t been measured by a healthcare professional
Yes caregivers know
When should fever on its own be investigated rigorously
- age <3 mo: the risks of fever greater than in other age groups
- Unwell for other reasons: confusion, low bp, dyspnoea, photophobic
- Immunocompromised: especially neutropenia - risk factor for bacterial sepsis
- Fever duration >10 days. Might not be URTI, eg. Lymphoma,
