signs and symptoms of infection JH Flashcards
what is an infectious disease?
Infection is the invasion of an organism’s body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the
toxins they produce
what can infectious disease be caused by?
- Virus
- Bacteria
- Fungus
- Parasites
what is an infection that is inactive/ dormant called?
latent infection, e.g. latent tuberculosis
what are the general signs and symptoms of infection?
- fatigue
- loss of appetite
- weight loss
- fevers
- night sweats
- chills
- aches and pains
how do you determine the severity of an infection?
- heart rate
- respiratory rate
- temperature
- blood tests:
– Full blood count (white cells raised in response to infection)
– C-reactive protein – none specific marker of
infection/inflammation - Other tests based on symptoms eg. urine dipstick, chest X-ray
what are the normal ranges for testing for infection?
- Blood pressure - normal 120/80mmHg
- Heart rate - normal 60-100bpm
- Respiratory rate - normal 12-20rpm
- Temperature - normal 37⁰C
White cell count - normal 4-11x109/L - C-reactive protein - normal <5mg/L
- Urine dipstick – is it positive for any components?
- Chest X-ray – are there any areas of consolidation?
- Microscopy, culture and sensitivity
what are normal CRP levels? when do they rise?
(5-10 mg/L) start to rise within 2 hrs of
inflammatory event, reaching up to 50,000x normal within 48 hrs.
what are some advantages of CRP?
CRP levels are high during bacterial infection (40-200 mg/L),
but significantly lower during viral infection (10-40 mg/L; eg. CRP
influenza: 18-32 mg/L; other viruses: 13-25 mg/L; bacteria: 99-173 mg/L
Provides possible test to distinguish bacterial vs viral infections
what are some disadvantages of CRP?
not sufficiently reliable for clinical differentiation of viral and bacterial infections because serum CRP ranges overlap, e.g. viral
infection vs early stage (low bacterial cell number) of bacterial infection.
CRP rises in response to inflammation, but may not be infection
when do you want to identify the organism that is causing the infection?
- Carried out in more severe infections or when
needed to determine most appropriate
treatment - In less severe infections – treatment is
empirical ie. chosen based on most likely
organism/spectrum of antibiotic – normally
based on guidelines - In severe infections – empirical treatment
is often used to give quick initial therapy
how do you identify the organism?
Microbial culture
microscopy
PCR- test for genetic material from specific organism eg virus
how should you be vigilant for signs of sepsis?
sweaty skin
disorientation
shivering
high HR
extreme pain
SOB
who should you have a lower threshold for concern for sepsis?
Infants
Patients who may have communication challenges
Immunocompromised/long term steroids
Indwelling catheters/lines
Recent surgery/injury
And other higher risk patients
what is the sepsis 6?
Within the first hour:
* Oxygen
* Cultures
* IV antibiotics
* Fluid resuscitation
* Blood tests including lactate
* Fluid balance monitoring/urine
output
what does an elevated lactate indicate?
- Patients with elevated lactate levels are
seriously ill and require urgent and effective
management - Measuring lactate levels provides useful
information about the progression of the
condition and the effectiveness of the
treatment
what is lactate?
metabolite of glucose produced by tissues
in the body under conditions of insufficient oxygen supply. Lactate is normally cleared by the liver and the kidneys, and the blood lactate concentration in unstressed patients is 1-1.5 mmol/L
in critically ill patients what happens to the lactate?
lactate is often elevated to above 2 mmol/L, with lactate levels above 4 mmol/L indicating the need for immediate resuscitation and ICU admission
what are the risk factors for infection?
– Age
– Comorbidities
– Current treatment
– Nutritional status
– Mechanical barriers
– Lifestyle e.g. travel, occupational risk
– Invasive procedures
– Hospitals
– Care setting
who would be an example of an immunocompromised patient?
Caused by a number of conditions, including:
– Congenital
– Asplenia
– HIV
* Or as an adverse effect/complication of treatment, including
– Transplantation
– Chemotherapy
– Steroids
how should you avoid infection?
- Healthy lifestyle
- Rest, exercise, good nutrition
- Good hand hygiene
- Avoiding large crowds/individuals with infection
- Good mouthcare
- Not sharing towels etc.
- Wear shoes to protect feet
- Avoiding cleaning waste products e.g. animal/baby
- Have appropriate vaccinations
how does antibiotic resistance spread?
spreads through populations of bacteria
when new generations inherit antibiotic resistance genes, and/or when bacteria share or exchange sections of genetic material with other bacteria
who are most likely to get better without antibiotic treatment?
People with common colds, sore throat, flu, otitis media and other self-limiting conditions may not know that they are likely to get better without treatment and they may expect to
be prescribed an antimicrobial
what is the start smart then focus plan?
- Do not start antimicrobial therapy unless there is clear evidence of infection
- Take a thorough drug allergy history
- Initiate prompt effective antibiotic treatment within one hour of diagnosis (or as soon as possible) in patients with severe sepsis or life-threatening infections
- Avoid inappropriate use of broad-spectrum antibiotics
- Comply with local antimicrobial prescribing guidance
- Document clinical indication, drug name, dose and route on drug chart and in clinical notes
- Include review/stop date or duration
- Obtain cultures prior to commencing therapy where possible (but do not delay therapy)
Then focus…..
This means: - Reviewing the clinical diagnosis and the continuing need for antibiotics at 48-72 hours and documenting a clear plan of action
what are the 5 antimicrobial prescribing decisions?
- Stop antibiotics if there is no evidence of
infection - Switch antibiotics from intravenous to oral
- Change antibiotics – ideally to a narrower
spectrum – or broader if required - Continue and document next review date or
stop date - Outpatient Parenteral Antibiotic Therapy
(OPAT)
what are the 5 things you should do about infection in primarycare/ community?
- Give self care or safety netting advice
- Use clinical scoring tools where
appropriate e.g. FeverPain - Promote vaccinations
- Clinical check of antibiotic prescriptions
against guidance - Give adherence advice
- Reinforce good hand hygiene
