Infectious Disease Flashcards
What is the purpose of vaccination?
A weakened or inactive version of the pathogen is given to stimulate an immune response, reducing the risk and severity of infection with that pathogen.
What are the live vaccines?
MI BOOTY:
MMR
Influenza (nasal)
BCG
Oral polio
Oral rotavirus
Typhoid fever
Yellow fever
What is included in the 6-in-1 vaccine?
- diphtheria
- tetanus
- pertussis
- polio
- haemophilus influenzae type B
- hepatitis B
When is the 6-in-1 vaccine given?
8 weeks
12 weeks
16 weeks
What vaccines are given at 8 weeks old?
- 6-in-1 vaccine
- meningococcal B
- rotavirus (oral)
What vaccines are given at 12 weeks old?
- 6-in-1 vaccine (again)
- pneumococcal
- rotvirus (oral) (again)
What vaccines are given at 16 weeks old?
- 6-in-1 vaccine (again)
- meningococcal B (again)
What vaccines are given at 1 year old?
- haemophilus influenza B
- meningococcal C
- meningococcal B (again)
- pneumococcal (again)
- MMR
What vaccines are given yearly at 2-8 years old?
Influenza vaccine (nasal)
What vaccines are given at 3 years 4 months old?
- diphtheria
- tetanus
- pertussis
- polio
- MMR (again)
What vaccines are given at 12-13 years old?
HPV vaccine (2 doses 6 months apart)
What vaccines are given at 14 years old?
- tetanus
- diphtheria
- polio
- meningococcal A, C, W and Y
When should the HPV vaccine be given?
To boys and girls aged 13 to 14 years, with two doses spaced 6 to 12 months apart.
It should be given before they become sexually active.
What strains of HPV does Gardasil (current NHS vaccine) protect against?
Strains 6 and 11 (genital warts).
Strains 16 and 18 (cervical and anal cancer).
Who is the BCG vaccine offered to?
Offered from birth to babies who are at higher risk of tuberculosis:
- relatives from countries of high TB prevalence
- urban areas with high rates of TB
- close contact with people that have TB
Counselling on the link between the MMR vaccine and autism.
Andrew Wakefield published a paper in 1998 in the Lancet, where he performed a series of tests on 12 children with autism and chronic enterocolitis. He reported it appeared they started having features of autism after the MMR vaccine. This was very anecdotal evidence based on parents perceptions about when the issues started. This caused a very big media response that generated a lot of fear amongst parents and uncertainty amongst doctors.
Since then the MMR vaccine, as well as other vaccines, have been extensively investigated with much more rigorous scientific research and statistical power, such as a meta-analysis with over one million patients. All subsequent scientific literature has disproved any link between the MMR and autism.
What is the pathophysiology of sepsis?
An overwhelming inflammatory response caused by the release of cytokines by macrophages, lymphocytes and mast cells (ie. cytokine storm).
Cytokines stimulates inflammation and the release of nitrous oxide, which causes vasodilation. This causes a distributive shock.
Pathophysiology of disseminated intravascular coagulopathy (DIC).
Activation of the coagulation system in sepsis leads to the deposition of fibrin throughout the circulation.
It also leads to consumption of platelets and clotting factors.
This leads to thrombocytopenia, haemorrhages and an inability to form clots and stop bleeding.
Why does blood lactate rise in sepsis?
Hypo-perfused tissues attempt to produce energy via anaerobic respiration.
What is septic shock?
The body responses to distributive shock by raising heart rate.
When the heart can no longer compensate, blood pressure falls and results in tissue hypo-perfusion. This leads to a rise in blood lactate as the organs begin anaerobic respiration.
Signs of sepsis in children.
- fever or hypothermia
- poor feeding
- high pitched or weak cry
- floppy baby
- skin colour changes
- deranged physical observations
Working diagnosis for infants under 3 months with fever.
Sepsis until proven otherwise.
Immediate sepsis management.
Addition investigations for sepsis.
- CXR (?pneumonia)
- abdominal / pelvic ultrasound (?intra-abdominal infection)
- lumbar puncture (?meningitis)
- meningococcal PCR
- serum cortisol (?adrenal crisis)
When can antibiotics be stopped in sepsis?
Low suspicion of bacterial infection;
OR
Patient is clinically well AND two CRP results are negative at 48 hours.
What is meningitis?
Inflammation of the meninges, usually due to bacterial or viral infection.
What is meningococcal septicaemia?
Meningococcus bacterial infection in the blood stream, which causes a non-blanching rash.
This rash indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
What is the most common cause of bacterial meningitis in children?
Neisseria meningitidis
Streptococcus pneumoniae
What is the most common cause of meningitis in neonates?
Group B streptococcus (GBS)
Presentation of meningitis.
- fever
- neck stiffness
- vomiting
- headache
- photophobia
- altered consciousness
- seizure
- non-blanching rash
Presentation may be non-specific in babies:
- hypotonia
- poor feeding
- lethargy
- hypothermia
- bulging fontanelle
NICE recommend a LP in which circumstances?
- under 1 month with fever
- 1 to 3 months with fever and clinically unwell
- under 1 year with unexplained fever and other features of severe illness
What are the two examination tests you can perform to look for meningeal irritation?
- Kernig’s
- Brudzinski’s test
What is Kernig’s test?
Flex the hip and knee to 90°, then extend the knee. If there is resistance or pain, the patient is Kernig sign positive.
What is Brudzinski’s test?
Lie supine and lift the head, bringing the chin to the chest. If this causes flexion of the hips, the patient is Brudzinski sign positive.
Bacterial vs viral CSF culture.
Presentation of mumps.
Prodrome period of flu-like symptoms, then:
- fever
- muscle aches
- lethargy
- reduced appetite
- headache
- dry mouth
PAROTID GLAND SWELLING with associated pain is a key feature.
