Infectious disease 2 Flashcards
SBA1
One day old baby girl born after prolonged delivery, becomes drowsy High temp, tachycardia, tachypnoea
On examination, T: 38.9, HR: 170bpm, RR: 30. Which is the most likely causative agent?
A.Neisseria meningitis
B.Streptococcus pneumonia
C.Listeria monocytogenes
D.Group B streptococcus
E.E. Coli
D Group B streptococcus
SBA2
21 y old wild med student- neck stiffness + photophobia, non blanching rash What would LP findings show?
A.Turbid colour, Increased polymorphs, normal monocytes, low glucose, high protein
B.Clear colour, normal polymorphs, high lymphocytes, normal glucose, high protein
C.Turbid colour, normal polymorphs, high lymphocytes, low glucose, normal protein
D.Cloudy colour, normal polymorphs, high lymphocytes, low glucose, high protein
E.Clear colour, high polymorphs, normal lymphocytes, low glucose, high protein
- Neisseria meningitis so bacterial so:
Colour: Turbid
Polymorphs: High
Monocytes: Normal
Glucose: Low
Protein: High
SBA3
A 72-year-old patient with a new onset murmur, fever and clubbing presents with blood in his stools and weight loss over the past 5 months. Which is the most likely causative agent?
A.Staph aureus
B.Staph epidermis
C.Streptococcus viridian
D.Streptococcus bovis
Enterococci
D Streptococcus bovis
Patient has Infective endocarditis AND Colorectal cancer
[NB Infective endocarditis causes weight loss but would not cause blood in stool]
This pathogen causes both
SBA4
Fifteen year old boy with Di George syndrome had a dental tooth extraction two weeks ago
Visits GP. New murmur on left sternal edge on auscultation.
Basic observations:
BP 110/80, HR: 95, Temperature: 38.5, SaO2 98% on air.
What is the most likely causative agent?
A.Staph aureus
B.Staph epidermis
C.Streptococcus viridian
D.Streptococcus bovis
Enterococci
C.Streptococcus viridian
SBA5
A 24 year old medical student comes back from their holiday and presents to A&E with profuse diarrhoea of rice water appearance. There is no blood. What is the most likely causative agent?
A.Entamoeba histolytica
B.Staph aureus
C.Bacillus cereus
D.E. Coli
Vibrio cholera
E Vibrio cholera
NB: Rice water diarrhoea= buzz word for vibrio cholera
SBA 6
A 40 year old woman presents to A&E with bloody, foul smelling diarrhoea. She went to a barbeque yesterday where she suspects she ate undercooked chicken. She has a fever and severe abdominal pain. What is the most likely causative agent?
A.Campylobacter
B.Shigella
C.Bacillus cereus
D.E. coli
Salmonella
A. Campylobacter
Campylobacter is more common than salmonella so best answer
What are contraindications for lumbar puncture?
- Signs of raised ICP
- Superficial infection over LP site
- Coagulopathy
What sign means you should admit patient to hospital for meningitis immediately?
Non-blanching rash = indicates Meningococcal septicaemia
Management in hospital of meningitis
Meningococcal septicaemia
IV benzylpenicillin Single dose
Bacterial meningitis
- IV ceftriazone
- Consider dexamethasone [but not if meningococcal septiceamia suspected]
- Cover listeria with ampicillin
- If consciousness affected- IV acyclovir [cover incase encephalitis]
What is given as prophylaxis to people in close contact with someone with meningitis?
- Rifampicin
- Ciprofloxacin
Infective endocarditis
Definition
Epidemiology
Aetiology [Four causative organisms]
Risk factors
Symptoms
Signs
Buzzwords
Investigations
Management
Complications
Infective endocarditis
Definition
Infection of endocardial structures [mainly heart valves]
Epidemiology
Uncommon
Aetiology
- Bacterial
- Streptococci [abnormal valves]
- Staphycocci [prosthetic valves, IV drug use- risk factors which are not disease]
- Enterococci
-Other organisms - HACEK
Risk factors
Abnormal heart valves- [Streptococcus viridans]
Prosthetic heart valves [Staphylococcus epidermidis]
IV drug use- [Staphyloccous aureus]
Turbulent blood flow- ventricular septal defect/patent ductus arteriosus
Recent dental procedures
Symptoms
- Weight loss
- Fatigue/malaise
- Fever
- Confusion
- Arthralgia/Myalgia
Signs
- Pyrexic
- New murmur [Mitral > Aortic > Tricuspid > Pulmonary]
- Tachycardia
- Anaemia
- Clubbing [strep viridans especially- b/c more chronic]
- Splenomegaly
- Vasculitic lesions
- Osler’s node-fingers, painful [Ouch]
- Janeway lesions - not painful
- Splinter haemorhhages
- Roth spots - petechiae on retina [Lesions get disloged and bacteria goes to small vessels]
- Lesions on pharyngeal + conjunctival mucosa
OR Mnemonic for presentation: FROM JANE
Fever
Roth Spots
Osler’s nodes
Murmur
Janeway lesions
Anaemia
Nail bed/splinter haemorrhage
Emboli- of vegetations/bacteria
Buzzwords
New murmur
Dental procedure
Prosthetic valve
Vegetation on echo
Indwelling catheter
Right heart [can also affect left, but most other pathologies don’t affect right side, so if R, consider infective endocarditis]
Investigations
- Blood cultures- THREE, taken one hour apart within a 24 hour period
- Bloods:
FBC- anaemia [normocytic], high neutrophils
U + E
High ESR
High CRP
Rheumatoid factor positive
- Transthoracic echocardiogram- Urgent [if nothing shown, transoesophageal echo more specific]
- Dukes classification
Management
-Broad spectrum antibiotics before cultures come back
[If can wait until after cultures come back to give specific Abx, then do]
- Antibiotics for four to six weeks
[at least 6 weeks if prosthetic valve]
Native valves
- Benzylpenicillin + gentamicin - Strep viridans
- Flucloxacillin - Staph aureus
Prosthetic valves
- Flucloxacillin/Vancomycin + rifampicin + gentamycin - Staph epidermidis
Penicillin allergic/resistant
- Vancomycin instead of penicillin
Complications
Congestive cardiac failure
Valve incompetence
Aneurysm + rupture
Systemic embolisation
Renal failure
Glomerulonephritis
Gastroenteritis
Definition
Aetiology-fill in table
Viral organisms
Bacteria
Protozoal
Symptoms
Investigations
Management
Gastroenteritis
Definition
Acute inflammation of GI tract lining associated with nausea, vomiting, diarrhoea and abdo pain
Aetiology
Viral organisms
Rotavirus, adenovirus, calcivirus, astrovirus
Bacterial organisms
Campylobacter jejuni, E Coli [0157]/haemorhhagic e coli, Salmonella, Shigella, Vibrio cholera, Bacillus cereus, C difficile
Protozoal
Entaemoaba histolytica, giardia lamblia, cryptosporidians parvus
- Bacterial causes of diarrhoea and history buzzwords
BEVS CS
Bacillus cereus [reheated rice, cerebral abscess]
E Coli [leafy vegetables]
Vibrio cholera [rice water stools, poor sanitation, shock]
Salmonella [eggs, poultry, constipation, in Payer’s patches in small intestine]
C difficile [antibiotic use, >70 y old, previous C diff, antiperistaltic drugs]
Staph aureus [food, 1-6hr after eating]
- Bacterial causes of dysentery [bloody diarrhoea] and history buzzwords
CHESS
Campylobacter jejuni [uncooked poultry]
Haemorrhagic E coli [leafy vegetables, develops into haemolytic uraemic syndrome]
Entamoeba histolytica [poor sanitation, MSM, tropical climates]
Shigella [person to person contact, poor sanitation, MSM]
Salmonella [eggs]
Symptoms
Nausea
Vomiting
Diarrhoea {+/- blood]
Abdo pain
Fever + malaise
Investigations
Examination:
Dehydration- mucous membranes, cap refill, skin turgor
Temperature
Shock- high HR, low BP
Bloods:
FBC
U + E [low K+ if severe diarrhoea and vomiting]
ESR + CRP- high
Stool MC+S [if systemic signs of illness]
Bacteria, ova cyst/eggs, parasites
Management
If no systemic illness:
Bed rest
Oral rehydration solution- electrolyte replacement
No stool MCS
If systemic illness:
[Fever>39C, >two weeks, dehydration, blood in stool]
Admit to hospital
Oral fluid/ IV fluid if severe vomiting
Stool MC+S [direct faecal smear + culture] + give antibiotics if bacterial cause identified
Check hydration -mucous membranes -skin turgor -capillary refill Check for shock -HR -BP Temperature Bloods - - - -[low K+] -Stool MCS for _._,_ usually only do if -Travel abroad? -Prolonged symptoms Management No systemic signs - - - Severe illness - - - - - -
What causative organism does non blanching rash suggest in meningitis?
Neisseria meningitidis
A 37-year-old bride-to-be returned from Jamaica 3 days ago, where she partied and explored the local cuisine with her best friends. She presents to her GP complaining of being jaundiced with right upper quadrant pain and fever. What is the most likely cause of her symptoms?
A.Alcoholic hepatitis
B.Gall stones
C.Cholecystitis
D.Hepatitis A
Hepatitis C
D Hepatitis A
[Hep A is faeco-orally transmitted]
Hepatitis
Definition
Aetiology
Transmission routes [viral]
Symptoms + different presentations of different viral hepatitis
Investigations
Management [for different types of viral hepatitis]
Hepatitis
Definition
Inflammatory liver disease
Aetiology
Viral-A to E
Alcoholic
Autoimmune
Transmission routes
Hep A + E:
Faeco oral [vowels hit the bowels]
Hep B:
Blood - transfusion, IV drugs
Birthing- mother to child, perinatal
Baby making- MSM, unprotected sex
Hep C
Contaminated blood products [transfusion, IV drugs]
Hep D:
Needs infection with hep B to enter- attaches to hep B antigen
[Two Ds stacked on top of each infection makes a B]
Symptoms
Triad:
- Fever
- Jaundice
- Raised ALT + AST
Also:
Nausea
Vomiting
Anorexia
RUQ pain
Hep A
Acute
Asymptomatic
Travel history
Hep B
Acute= 90%, chronic= only 10%
Hep C
Chronic
Risk of hepatocellular Carcinoma
Hep E
Enteric
E- immunodeficiency
Expectant mothers- pregnancy
Epidemics- contaminated water
Travel history
Investigations
FBC
LFT
U+E
Clotting- prolonged PT time=liver damage [sensitive]
Viral serology
Viral PCR
Ultrasound abdo- rule out liver malignancy
Liver biopsy- monitor inflammation, cirrhosis
Management [for different types of viral hepatitis
Hep A + E= supportive treatment, avoid alcohol
Hep B= acute= symptomatic supportive treatment, chronic= antiviral [peginterferon alpha, tenofovir]
Hep C= Anti viral [NS5A inhibitor, NS3/4 protease inhibitor]
Meningitis vs Encephalitis- fill in table
Hep B serology and pattern of antibodies table
Hep B serology + pattern of antibodies graph
Table summarising lumbar puncture findings- fill in normal findings
Table summarising lumbar puncture findings- fill in:
Bacterial meningitis findings
NB: neutrophils= polymorphs
Table summarising lumbar puncture findings- fill in:
Viral meninigitis findings
Table summarising lumbar puncture findings:
fill in:
TB/fungal meningitis findings
