Fever and PUO Flashcards

1
Q

Define PUO?

A
Prolonged illness (2-3 weeks)
Fever (>38.3) on several occasions
No diagnosis after intelligent investigations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the normal oral temperature range?

A

35.8-37.8

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

Describe the diurnal variation in body temperature?

A

Lowest in morning
Highest in afternoon
Varies by 0.5-1

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

Where is body temperature regulated?

A

Anterior hypothalamus

Temperature sensitive neurons

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

Define fever?

A

Early morning oral temp > 37.2

Oral temp > 37.8 at any time

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

Describe how measurement of temperature may vary?

A

Oral: < core body temp by 0.5
Axillary: < core body temp by 1
Ear probe closer to core temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the optimum temperature for fighting an infection?

A

39.5

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

Describe rigor?

A
Feeling of intense cold
Uncontrollable shivering
Pallor
Pilo-erection
Exhaustion afterwards with high fever (>39)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the most common cause of fever of short duration?

A

Infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which life-threatening conditions associated with fever of short duration must be detected and treated immediately?

A
Meningococcaemia
Falciparum malaria
Bacterial meningitis
Post splenectomy sepsis
TSS
Necrotising soft tissue infections
Head and neck space infections
Febrile neutropaenia
Acute staph aureus endocarditis
Severe pneumonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the symptoms of TSS?

A

Hypotension
Fever
Rash

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the symptoms of necrotising soft tissue infections?

A

Severe local pains
Fever
Chills

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which patients presenting with fever are most at risk for a serious illness?

A
Recent OS travel
Asplenic
Neutropaenic
Elderly
Diabetic
IVDU
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which signs, along with fever, indicate a serious illness in a patient?

A

Shock
Impaired conscious state
Cyanosis
Tachypnoea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What symptoms that present with acute fever are warning bells?

A
Rapid onset/evolution
Rigors
Severe muscle pain
Impaired conscious state
Vomiting
Severe headache
Rash
Jaundice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is vomiting associated with fever an alarm bell?

A

Vomiting can be associated with raised ICP

Can be caused by toxins

17
Q

Why is severe headache associated with fever an alarm bell?

A

Meningitis

18
Q

Why is jaundice associated with fever an alarm bell?

A

Can be a marker of sever illness, especially sepsis

19
Q

Describe the management of a patient that presents with fever?

A

Investigations: FBE, CRP, renal function, liver function, blood and urine cultures, CXR
Empirical IV antibiotics (if bacterial infection likely)
Admit or prolonged stay in ED

20
Q

Describe how the WCC and CRP levels may change through the course of an infection?

A

takes time for immune system to respond > may take up to 12 hours to see elevation

21
Q

What should be considered in a patient with prolonged fever?

A
Occupation/animal exposure 
Country of origin 
Travel - local or OS for past 2 years
Contact with toddlers
Risk for SBE
New sexual contacts
New medications
22
Q

Why is country of origin important in prolonged infection?

A

Possibility of TB

23
Q

Why is any travel in the past two years significant for a patient presenting with prolonged fever?

A

Vivax malaria has prolonged liver phase

24
Q

What is the most common cause of prolonged fever in young couples with toddlers?

A

Acute CMV

Children are fine when infected, but transferred to adults > symptomatic 2-3 weeks later

25
Q

Describe the investigations that should be carried out on a patient with prolonged fever?

A
FBE 
ESR
CRP
LFT
CXR
Serology for unusual infections
Blood and urine cultures
26
Q

What may show up on an FBE of a patient with prolonged fever?

A

Atypical lymphocytosis: infectious mononucleosis (EBV< CMV, HIV)
Neutrophilia: bacterial/inflammatory process
EXCLUDE MALARIA

27
Q

What would a high ESR indicate in a patient with prolonged fever?

A

Non-specific

High with prolonged bacterial infection or vasculitis

28
Q

What would a very high CRP in a patient with prolonged fever suggest?

A

Bacterial infection/inflammation

29
Q

Why is a CXR performed in a patient with prolonged fever?

A

Atypical pneumonia

30
Q

Why aren’t empirical antibiotics given to a patient with prolonged fever?

A

Side effects of antibiotic may confuse clinical picture

31
Q

When would empirical antibiotics be given to a patient with prolonged fever?

A

If Q fever or atypical pneumonia were highly likely

32
Q

Describe the clinical approach to diagnosing PUO?

A

1) Onset and duration (when were they last well?)
2) Seek localising symtpoms
3) Establish severity (weight loss? night sweats?)
4) Is there really a fever?
5) Obtain information and review all results
6) Past Hx, family Hx, medications
7) Country of origin
8) Travel history (last 10 years)
9) Occupation, animal exposure
10) Sexual history and IVDU

33
Q

What are the differential diagnoses for PUO?

A

Infections
Connective tissue disorders
Malignancies
Other: drug fever, factitious fever, benign pyrexia

34
Q

Which infections could cause PUO?

A
Subacute bacterial endocarditis (SBE)
TB
Intra-abdominal abscess
HIV related opportunistic infection
Other: EBV, CMV, brucella, Q fever, malaria
35
Q

Which connective tissue diseases could cause PUO?

A
Polymyalgia rheumatica
Giant cell arteritis
Vasculitis
Adult Still's disease
SLE
Acute thyroiditis
Granulomatous diseases: sarcoidosis, Crohn's
36
Q

Describe the physical examination of a patient with PUO?

A
Eyes
Temporal arteries
Teeth and gums
Thyroid gland tenderness
Heart murmur/rub
Lymph nodes
Hepatosplenomegaly
Kidney mass
Rash/arthritis
37
Q

Describe the investigations for a patient with PUO?

A

Repeat and review basic bloods and cultures
MSU
ANA, RF, ANCA
Iron studies
LDH, beta 2 microglobulin
HIV serology
Consider serology for EBV, CMV, brucellosis, Q fever, psittacois, bartonella, syphilis
Consider TB
Imaging: CXR, CT abdo/pelvis, PET scanning
Tissue sample if you still don’t have a diagnosis