Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Infection > Pyrexia of Unknown Origin > Flashcards

Pyrexia of Unknown Origin Flashcards

1
Q

What is a fever?

A

Elevation of body temperature above normal (37oC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the variation of normal body temperature?

A

Normal body temperature has variation up to 0.8oC daily, being low in early morning and high in early evening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Fever is a normal part of what?

A

Systemic inflammatory response syndrome (SIRS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does SIRS stand for?

A

Systemic inflammatory response syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a pyrogen?

A

Substances that cause fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are examples of pyrogens?

A
  • Endogenous
    • Cytokines
  • Exogenous
    • Endotoxins from G-ve bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do pyrogens act on?

A

Hypothalamic thermoregulatory centre to cause reduced heat loss and hence fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does PUO stand for?

A

Pyrexia of unknown origin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is pyrexia of unknown origin?

A

Pyrexia with no diagnosis after:

  • 3 outpatient visits or
  • 3 days in hospital or
  • One week of outpatient investigation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the different classes of PUO?

A
  • Classical PUO
  • Nosocomial PUO
    • Develops in hospital, undiagnosed after 3 days
  • Neutropenic PUO
    • Undiagnosed fever in patient with neutrophils <500/mm3
  • HIV associated PUO
    • Fever in patient with HIV present and undiagnosed for more than 3 days in an inpatient or 4 weeks as outpatient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is nosocomial PUO?

A
  • Develops in hospital, undiagnosed after 3 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is neutropenic PUO?

A
  • Undiagnosed fever in patient with neutrophils <500/mm3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is HIV associated PUO?

A
  • Fever in patient with HIV present and undiagnosed for more than 3 days in an inpatient or 4 weeks as outpatient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some causes of classical PUO?

A
  • Infection
  • Malignancy
  • Collagen (inflammatory)
  • Other
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the most common causes of HIV associated PUO?

A
  1. Mycobacterium tuberculosis
  2. Mycobacterium ovium
  3. Unknown
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What parts of the history are important for assessment for PUO?

A
  • Travel, occupation, hobbies, family history, past medical and surgical history, drug history, pattern of fever
17
Q

What part of the examination are important for assessment for PUO?

A
  • Skin, eyes, oral cavity, nails and lymph nodes
18
Q

What are the initial investigations for PUO?

A
  • Simple things first
    • Chest X-Ray
    • Urinalysis and urine microscopy
    • Full blood count and differential white cell count
    • C-Reactive Protein and Erythrocyte Sedimentation Rate (acute phase reactants)
    • Blood cultures taken at times of fevers
    • Urea, creatinine, electrolytes, liver function tests
19
Q

What are some further investigations for PUO?

A
20
Q

What is a limitation of imaging for PUO?

A
  • Cannot always differentiate between infection and inflammation
  • Anatomical changes may not be present in immunocompromised hosts
21
Q

What imaging may be done for PUO?

A
  • USS
  • CT
  • MRI
  • Radio-labelled white cell scan
  • Isotope bone scan
22
Q

What invasive investigations may be done for PUO?

A
  • Obtain tissue for culture and histology (biopsy)
  • Bone marrow and liver often examined as part of blind investigation
    • Malignancy, TB, lymphoma
23
Q

What is the treatment of PUO?

A

Therapeutic trial:

  • Rarely used, but used if
    • Suspected mycobacterial infection (anti-tuberculosis therapy)
    • Suspected vasculitis or connective tissue disorder (steroids)
24
Q

What is a fabricated fever?

A

Fever is real but self-induced:

  • Microbiology may be strongest clue
  • Psychiatric expertise should be sought
25
Q

Describe the outcome of PUO?

A

Spontaneous resolution of PUO more common in young people

Some patients respond to NSAIDs or steroids

Regular re-appraisal required

26
Q

What are most HIV-related PUOs caused by?

A

3/4 patients:

  1. Mycobacterium tuberculosis
  2. Mycobacterium avium
  3. Unknown
  4. More than one causative disease

Infection (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions