Microbiology Flashcards
Gram positive bacteria have a ? proteoglycan cell wall and stain ? with Gram stain
thick proteoglycan cell wall
purple
Gram negative bacteria have a ? proteoglycan cell wall and stain ? with Gram stain
thin proteoglycan cell wall
pink
Classification of antimicrobial agents? (6)
- inhibit cell wall synthesis
- inhibit protein synthesis
- inhibit DNA synthesis
- inhibit RNA synthesis
- cell membrane toxin
- inhibit folate metabolism
Types of antimicrobials that inhibit cell wall synthesis? (2)
- B lactams
2. Gycopeptides
How do B lactams work?
- inhibit the enzymes responsible for building the proteoglycan cell wall of the bacteria i.e. penicillin binding protein
- bacteriocidal - prevents peptide cross linking thus daughter cells are weaker and lyse when they divide
Which bacteria are B lactam effective against?
Which bacteria are B lactam ineffective against?
a) gram +, gram -, enterococci
b) mycoplasma, chlamydia
Resistance against B lactams?
production of B lactamase
Penicillin
- which organisms?
- resistance?
Gram +
Broken down by B lactamase produced by Staph aureus
Amoxicillin
- broad or narrow?
- which organisms?
- resistance?
Broad spectrum Penicillin
Gram + Gram - Enterococci
Broken down by B lactamase produced by Staph aureus
Flucloxacillin
- broad or narrow?
- which organisms?
- resistance?
- narrow spectrum penicillin
- Gram +
- stable to B lactamase produced by Staph aureus
Piperacillin
- which organisms?
- resistance?
- example with Tazobactam?
Gram + Gram - Pseudomonas
Broken down by B lactamase produced by Staph aureus
Tazocin
What are Clavulanic Acid and Tazobactam?
B-lactamase inhibitors
Protect penicillins from B lactamase produced by Staph aureus
Allows broader spectrum
Examples of B lactams? (3)
- Penicillins
- Cephalosporins
- Carbepenems
Cephalexin
- type of B lactam
First generation cephalosporin
Cefuroxime
- type of B lactam
- resistance
Second generation cephalosporin
Stable to many B lacatamases produced by Gram -
Ceftriaxone
- type of B lactam
- broad or narrow?
- which organisms?
- association
- # 1 use
Third generation cephalosporin Broad Gram + Staph & Strep C difficile Meningitis first line
Cephtazidime
- type of B lactam
- which organisms?
Third generation cephalosporin
Pseudomonas
Extended Spectrum B Lactamases?
Organisms producing these are resistant to ALL cephalosporins
Carbepenems
- resistance
- broad or narrow?
- examples (3)
Resistant to Extended Spectrum B Lactamases Broad spectrum 1. Meropenem 2. Imipenem 3. Ertapenem
Key features of B Lactams (5)
- Non-toxic
- Renally excreted (low dose is renal impairment)
- Short half life (multiple daily doses)
- Do NOT cross BBB
- Cross-allergenic (if allergic to Penicillin 10% cross reactivity with Cephallosporins and Carbepenems)
Glycopeptides
- how do they work?
- which organism
- side effect
Inhibit cell wall synthesis
Gram - only
Nephrotoxic therefore drug level must be monitored
Vancomycin
- Class of Abx?
- use?
Glycopeptide
C difficile
Aminoglycosides
- mode of action?
- binding site
- toxicity? (2)
- which organism?
- inhibit protein synthesis
- 30s ribosomal subunit
1. ototoxic
2. nephrotoxic
Gram -ve
Gentamycin
- Class of abx?
- organisms?
- use
Aminoglycoside
Gram - especially Pseudomonas
Gram - sepsis
Tetracylines
- mode of action?
- binding site
- contraindications (2)
- which organisms? (3)
- association
- inhibit protein synthesis
- 30s ribosomal subunit
1. children
2. pregnant women
- chlamydia
- rickettsiae
- mycoplasma
- light-sensitive rash
Doxycyline
- class of Abx?
- organisms?
- Tetracycline
- intracellular chlamydia
Macrolide
- mode of action?
- binding site
- which organisms?
- indication
inhibit protein synthesis
50s subunit of ribosome
Gram + (Staph, Strep)
Pen allergic
Erythromycin
- class of Abx?
- organisms? (2)
Macrolide
- Staph
- Strep
Chloramphenicol
- mode of action?
- binding site?
- broad or narrow?
- associations (2)
- uses (2)
- avoid
- inhibit protein synthesis
- peptidyl transferase of 50s ribosomal subunit
- very broad
- aplastic anemia
- grey baby syndrome
- bacterial conjunctivitis
- Genuine Pen allergy - meningitis
- systemic use due to risk of aplastic anaemia
Oxazolidinones
- mode of action?
- binding site
- which organisms?
- indication
- example
- association
- inhibit protein synthesis
- 23s of 50s ribosomal subunit
- Gram +
- MRSE VRE
- Linezolid
- thrombocytopenia after prolonged use
Quinolones
- mode of action
- binding site
- which organisms?
- broad or narrow?
- indications (3)
- examples (3)
- inhibit DNA synthesis
- a-subunit of DNA gyrase
- Gram -ve
- broad
1. UTI
2. Pneumonia
3. atypical pneumonia
- Ciprofloxacin
- Levofloxacin
- Moxifloxacin
Nitroimidazoles
- mode of action
- broad or narrow?
- which organisms? (2)
- examples (2)
- indication
- related
- inhibit DNA synthesis
- narrow
1. anaerobic
2. protozoa
- Metronidazole
- Tinidazole
Giardia
Nitrofuratoin - UTI
Rifamycins
- mode of action
- binding site
- which organisms?
- indication
- examples (2)
- inhibit protein synthesis
- RNA polymerase
- mycobacteria
- TB
1. Rifampicin
2. Rifabutin
Rifampacin
- class of Abx
- use
- drug interactions (2)
- monitoring required
- side effects
- resistance
- Rifamycin
- TB
1. OCP
2. Warfarin - LFTs
- orange bodily secretions
- rapid resistance whereby chromosomal mutation changes B-subunit so that Rifampacin can’t bind to RNA polymerase
Daptomycin
- mode of action
- organisms
- indications (2)
- cell membrane toxin
- Gram +ve
1. MRSA
2. VRE
Colistin
- mode of action
- organisms
- indications
- administered by
- toxicity
- cell membrane toxin
- Gram -ve
- multi-drug resistant organisms
- IV only
- nephrotoxic
Sulfonamides
- mode of action
- indication
- used in conjunction with
- toxicity
- example
- inhibit folate metabolism
- PCP
- Trimethroprim
- teratogenic
- Sulphamethoxazole
Diaminopyrimidines
- mode of action
- indication
- toxicity
- example
- inhibit folate metabolism
- community acquire UTI
- teratogenic
- Trimethroprim
Mechanisms of Abx resistance? (4)
BEAT
- Bypass Abx sensitive step
- Enzyme-mediated drug inactivtion e.g. B-lactamase
- Accumulation inhibition
a) impaired uptake
b) increased efflux - Target altered in microbe
Major mechanism of resistance to B Lactams?
- example organisms (2)
Enzyme-mediated inactivation
- Staph aureus
- Gram -ve bacilli
Mechanism of resistance in MRSA?
Methicillin-Resistant Staph Aureus
Altered target, PBPs now have a low affinity for B Lactams
Mechanism of resisatnce of Strep pneumonniae?
Altered target, lowered affinity for B lactams
Can be overcome by increasing dose
Common organisms with Extended Spectrum B Lactamases? (2)
- E coli
2. Klebsiella
Which ABX?
Staph aureus
Flucloxacilin (unless allergy)
Which ABX?
Strep throat
Benzylpenicillin
Which ABX?
CAP (mild)
Amoxicillin
Which ABX?
CAP (severe)
Cefuroxime + Clarithromycin
Which ABX?
HAP
Cefuroxime
Which ABX? Bacterial meningitis (Meningococcus/Strep)
Ceftriaxione
Which ABX? Bacterial meningitis (Listeria)
Amoxicillin + Ceftriaxone
Which ABX?
UTI (community)
Trimethroprim
Which ABX?
UTI (hospital)
Augmentin or Cephalexin
Which ABX?
Sepsis (severe)
Cefuroxime
Metronidazole
Gent
Which ABX?
Neutropenic sepsis
Tazocin + Gentamycin
Which ABX?
Collitis (C diff)
Metronidazole
Natural reservoir of Influenza A (H1)
ducks
Natural reservoir of Influenza A (H1N1)
pigs
Who receives trivalent flu vaccine?
- type of vaccine?
At risk populations (health workers)
Inactivated
purified HA + NA rich
Who receives quadrivalent flu vaccine?
- type of vaccine?
Children
Live attenuated vaccine
HA rich
Why does influenza cause a respiratory illness? (4)
- sialic acid is only expressed
- virus enters through the mouth
- virus is activated by proteases expressed in the mouth
- can only fuse with mucus secreting cells
Where in the lungs can influenza virus survive?
LRTI not URTI as does not replicate well at low temperatures
Surface glycoproteins of influenza virus (2)
- cause of seasonal variation?
- NA neuraminidase activity
- cleaves sialic acid to allow virus to exit host cell - HA haemogglutinin activity
- binds to sialic acid receptors allowing virus to attach to host cell and causes membrane fusion
- RNA segments of the virus are prone to mutation hence variation in influenza virus to produced new strains
Antigenic Drift
mutation in HA/NA to give new strains of the virus therefore vaccine must be updated annually
Antigenic Shift
- which strain?
- how?
complete change of HA/NA
- only happens with Influenza A
- trading of RNA segments between human and animal strains
Protease that activates influenza virus?
clara tryptase
Severe outcomes of the flu? (4)
- secondary bacterial pneumonia
- mutant virus
- co-morbidity
- cytokine storm (H5N1)
Antivirals for flu? (3)
- Amantadine
- Tamiflu
- Oseltamivir
- Zanamivir
Mechanism of Amantadine/Rimantidine?
- which strain?
M2 ion channel inihibitor
Influenza A
Mechanism of Oseltamivir/Zanamivir?
- which one is oral?
- which one is inhaled powder/IV?
- which strain?
- who is treated?
Neuraminidase inhibitors Oseltamivir - oral Zanamivir - IV/inhaled powder Influenza A & B High risk groups
Aged ≥ 65 years Immunosuppressed Chronic respiratory disease Chronic heart disease Chronic liver disease Chronic neurological disease Diabetes mellitus Pregnant women Morbid obesity (BMI ≥ 40) Children
MIC
Minimum Inhibitory Concentration
How much abx is required to inhibit growth of organism in a test tube
Bacteriuria
presence of bacteria in urine
Cystitis
inflammation of the bladder, normally caused by infection
Uncomplicated UTI
Presence of UTI in functionally/structurally normal urinary system
Complicated UTI
Presence of UTI in functionally/structurally abnormal tract
Why does obstruction increase likelihood of UTI?
inhibits flow of urine, stasis of urine, increased chance of infection
Causes of obstruction within urinary tract
a) Extrarenal (5)
b) Intrarenal (6)
Extrarenal
- Valves
- Stenosis
- Bands
- Calculi
- Ureteral compression e.g. BPH
Intrarenal
- nephorcalcinosis
- uric acid nepropathy
- analgesic nephropathy
- PKD
- hypokalaemic nephropathy
- intrarenal lesions of sickle cell trait/disease
Neurogenic causes of urinary obstruction? (4)
- poliomyelitis
- tabes dorsalis (syphilis)
- diabetic nephropathy
- spinal cord injuries
Most common bacteria causing UTI?
E coli
Other bugs causing UTI? (5)
- Proteus fimbriae
- Klebsiella
- Staph epidermis
- Staph saprophyticus
- Enterococcus faecalis
Routes of infection of UTI (2)
- contamination from rectum
2. haematogenous route
Symptom of UTI (6)
- frequency
- dysuria
- abdo pain
- flank pain
- fever
- vomiting
Investigation of UTI (4)
- urine dipstick ( nitrites, leukocytes)
- MSU MC+S
- Bloods - FBC, U+Es, CRP
- Renal USS
Which of the following cell types on microscopy suggests a poorly taken sample.
- White blood cells
- Squamous epithelial cells
- Red blood cells
Squamous epithelial cells
Treatment for uncomplicated lower urinary tract infection in women?
Trimethroprim 3/7
Treatment of UTI in women with previous history of UTIs or men?
Nitrofuratoin 7/7
Treatment of pyelonephritis?
Co-amoxiclav + Gentamycin
Pathogenesis of CNS infection (4)
- haematogenous spread
- direct infection
- PNS to CNS
- local extension
Common organisms causing bacterial meningitis (2)
- N.meningitidis (Gram -ve)
2. Step pneumoniae (Gram +ve)
Common organisms causing bacterial meningitis in neonates? (3)
- Group B Strep
- Listeria
- E coli
Common organisms causing bacterial meningitis in elderly? (3)
- Group B Strep
- Listeria
- TB
Symptoms of bacterial meningitis? (8)
- headache
- neck stiffness
- fever
- focal neurology
- rash
- photophobia
- irritability
- vomiting
Common organisms causing viral meningitis? (3)
- Coxsackie
- Mumps
- HSV 2
Organism causing fungal meningitis?
Cryptococcus neoformans
Meningococcal septicaemia
- percentage
- clinical spectrum (4)
- 40%
1. capillary leak - hypoalbuminaemia
2. coagulopathy
3. metabolic derangement
4. myocardial failure
Likely organisms causing chronic meningitis? (2)
- TB
2. Cryptococcus
Encephalitis
- transmission
inflammation of brain parenchyma
person to person or through vectors e.g. ticks
leading cause of encephalitis internationally?
Western Nile Virus
Treatent of meningoencephalitis?
Ceftriaxone + Acyclovir
Normal CSF Levels in adult
WCC
Protein
Glucose
0 - 5
- 15 - 0.4
- 2 - 3.3
CSF levels in bacterial meningitis?
WCC
Glucose
HIGH with polymorphs
LOW
CSF levels in viral meningitis?
WCC
Glucose
HIGH with mononuclear cells
Normal
CSF levels in TB/cryptococcus meningitis?
WCC
Protein
HIGH with mononuclear cells
HIGH
Pathophysiology of cerebral abscess? (5)
- otitis media
- mastoiditis
- paranasal sinuses
- endocarditis
- haematogenously
Pathophysiology of spinal infection (3)
- open spinal trauma
- infection in adjacent structures
- haematologenously
Risk factors for spinal infection (7)
- age
- IVDU
- DM
- transplantation
- long-term steroids
- malignancy
- malnutrition
Hepatitis A
- type of virus
- immunoglobulin associated with acute infection
- immunoglobulin associated with previous vaccination
- diagnosis
- transmission
- incubation
- symptoms (7)
- EMQ (3)
RNA virus IgM IgG Anti-HAV IgM fecal-oral 2-6 weeks
- fatigue
- low grade fever
- diarrhoea
- nausea
- pruritis
- jaundice
- arthralgia
- undercooked fish
- South East Asia
- Mardi Gras
Hepatitis B
- type of virus
- transmission (3)
- acute/chronic
- incubation
- lab findings
dsDNA virus
- sexual
- vertical
- blood products
Acute 6/12
2 - 6 months
increased AST, increased ALT due to liver inflammation
Hepatitis B - diagnosis HBsAg HBeAg HBcAb IgM HBcAb IgG HBsAb
HBsAg - active infection marker HBeAg - high level of viral replication HBcAb IgM - recent infection HBcAb IgG - exposure to HBV/chronic infection HBsAb - immunity HBV vaccination
Complications of HBV (3)
- Fibrosis
- Cirrhosis
- HCC
Treatment of HBV (3)
- IFN alpha - can clear virus
- Lamivudine - can suppress viral replication
- Tenofovir - can suppress viral replication
Hepatitis C
- type of virus
- transmission
- acute/chronic
- incubation
- lab findings
RNA virus blood products 80% progress to chronic 2 weeks - 6 months ALT - responds to viral load
Hepatitis C diagnosis
Anti - HCV
HCV RNA
Anti-HCV Ab
Anti - HCV - active infection
HCV RNA - acute HCV
Anti-HCV Ab - chronic HCV
Treatment of HCV (2)
- Peg IFN - allows less drug to be given and is better tollerated, sustained response
- Ribavirin
Complications of Hep C (2)
- Cirrhosis
2. HCC
Hepatitis D
- type of virus
ONLY if you already have HBV
RNA virus
Hepatitis E
- type of virus
- transmission
- incubation
- poor prognosis
RNA virus
faecal-oral
3-8weeks
pregnancy
Which organisms cause bloody diarrhoea? (5)
SECSY
- Salmonella
- E coli
- Campylobacter
- Shigella
- Yersinia enterocolitis
Two viruses commonly causing GI infection in children?
- Rotavirus
2. Adenovirus
4 lab findings for Staph aureus
- Catalase +
- Coagulase +
- Gram +
- yellow colonies of blood agar, B haemolytic
Pathophysiology of Staph aureus as GI infection?
- incubation
- duration
- transmission
- treatment
- aerobic/anaerobic?
- produces enterotoxin
- release IL-1 IL-2
- prominent vomiting & watery non-bloody diarrhoea
2-7days
B.cereus
- association
- pathophysiology (3)
- aerobic/anaerobic?
REHEATED RICE 2 spore toxins 1) heat stable - emetic causing 2) heat labile - diarrhoeal causing sudden vomiting + non-bloody diarrhoea
aerobic
Clostridium botulinum
- associations (2)
- pathophysiology (3)
- symptoms
- aerobic/anaerobic?
vaccum-packed/canned foods
1) honey - children
2) beans - students
- ingestion of preformed toxin
- blocks Ach release from peripheral nerves
- paralysis
descending paralysis
anaerobic
Clostridium perfringens
- association
- pathophysiology (2)
- incubation
- symptoms (2)
- aerobic/anaerobic?
- reheated meats
1. enterotoxin binds to TCR & MHC - massive cytokine release causing systemic toxicity
- 8-16hrs
1. watery diarrhoea
2. cramps
anaerobic
Clostridium difficile
- who
- why?
- pathology
- treatment
- aerobic/non-aerobic?
- hospitalised patients
- Abx therapy cephalosporins/fluorquinolones
- pseuomembranous colitis
- Stop Abx
Metronidazole/Vancomycin - anaerobic
Listeria monocytogenes
- susceptible cohorts? (2)
- type of bacteria (2)
- maternal concerns (3)
- source of foods (3)
- symptoms (5)
- treatment
- immunocompramised
- pregnant women
B haemolytic , tumbling mobility
- miscarriage
- stillborn
- mental retardation of fetus
- unpasteurised dairy products
- pre-packaged meals
- cured meats
- watery diarrhoea
- cramps
- fever
- headache
- vomiting
Ampicillin
Types of E.coli? (4)
ETEC
EIEC
EHEC
EPEC
ETEC E.coli
- what
- who
- 2 toxins
- source
- Toxigenic
- travellers diarrhoea
1. heat labile - stimulates adenyl cyclase & cAMP
2. heat stable - stimulates guanylate cyclase
food/water contaminated with human faeces
EIEC
- what
- source
- Invasive dysentery
- food/water contaminated with human faeces
EHEC
- what
- source
- cause
- result
- Haemorrhagic
- food/water contaminated with human faeces
- verotoxin
- HUS
EPEC
- what
- source
- who
- complication
- Pathogenic
- food/water contaminated with human faeces
- infantile diarrhoea
- HUS
Typhoid/Enteric Fever
- causative agent
- multiplies where?
- symptoms (2)
- signs (5)
- treatment
- salmonella typhi + paratyphi
- Peyers patches
1. slow onset fever
2. constipation
- bradycardia
- splenomegaly
- rose spots
- anaemia
- leukopenia
- Ceftriaxone
Salmonella enteritides
- association (3)
- symptoms
- treatment
- poultry
- eggs
- meat
bloody diarrhoea
self-limiting/ceftriaxone
Dystenery
- causative agent
- enterotoxin
- symptoms (3)
Shigella dysenteriae Shiga enterotoxin Invades mucosal cells of distal ileum and colon causing inflammtion 1. fever 2. pain 3. bloody diarrhoea
Vibriosis cholera
- source
- symptoms
- pathophysiology
- organism appearance
water contaminated with human faeces - SHELLFISH
rice water diarrhoea
cholera toxin causes cAMP to open Cl channels -> massive loss of electrolytes
comma shaped
Campylobacter jejuni
- sources (3)
- organism appearance
- duration
- symptoms (4)
- complications (3)
- treatment
food/water contaminated with animal faeces
- poultry
- meat
- unpasteurised milk
can be up to 20days
- fever
- headache
- severe abdo cramps
- foul-smelling bloody diarrhoea
- Reactive arthritis
- Reiter’s syndrome
- Guillan Barre syndrome
What is Reiter’s syndrome? (3)
- arthritis
- uvetitis
- conjunctivitis
Yersinia
- preference
- source
- associations (3)
- 4*C cold enrichment
- food contaminated with domestic animals faeces
1. arthritis
2. necrotising granulomas
3. erythema nodosum
Diarrhoea causing protozoa (3)
- Entamoeba histolytica
- Giardia lamblia
- Crystosporidium parvum
Entomoeba histolytica
- EMQ hint
- histology
- symptoms (6)
- treatment
men who have sex with men flask-shaped ulcer in colon 1. diarrhoea 2. flatulence 3. dysentery 4. tenesmus 5. weight loss 6. RUQ pain due to liver abscesses - Metronidazole
Giardia lamblia
- EMQ hints (4)
- histology
- source
- symptoms (4)
- test
- treatment
- travellers
- hikers
- MSM
- mental hospitals
faecally contaminated water containing cysts
- flatulence
- foul-smelling non-bloody diarrhoea
- cramps
- malabsorption of protein & fat
ELISA string test
Metronidazole
Cryptosporidium parvum
- who
- where
- test
- immunocompramised
- jejenum
- Kinyoun acid fast stain
Secretory Diarrhoea (2) - cause
- no fever
- no WCC in stool sample
- enterotoxin causes massive cytokine production & supression of adaptive immune response
Inflammatory diarrhoea (2)
- fever
2. WCC in stool sample - neutrophils
Enteric fever (2)
- fever
2. WCC in stool sample - mononuclear cells
Viruses causing diarrhoea (5)
- norovirus
- enteroviruses
- rotavirus
- adenovirus
- poliovirus
Rotavirus
- who
- type of virus
- symptoms
- children
- ds-DNA
- secretory diarrhoea, massive cytokine production
- low grade fever
Adenovirus
- who
- symptoms
- which strains cause bloody diarrhoea?
- children
- bloody diarrhoea
- 40 and 41
Norovirus
- who
- immunity
- outbreaks
- predominant symptom
- adults
- no lifelong immunity
- high infectivity, high resilience
- vomiting ++
Notifiable diarrhoea causing diseases (5)
- Campylobacter
- Clostridium difficile
- Listeria
- Virbrio cholera
- Yersinia
Passive immunity
Transfer of immune effectors i.e. immunoglobulins e.g. HBIG, VZIG
Types of vaccine (5)
- Immunoglobulin
- Anti-toxins
- Inactivated
- Subunit
- Live attenuated
Examples of live attenuated vaccines (6)
- contraindicated
- advantage
- MMR
- Rotavirus
- Yellow fever
- VZV
- BCG
- Polio
- in pregnancy/immunosuppressed
- act most like the real infection therefore give long-lasting immunity
Examples of inactivated vaccines (3)
- Rabies
- Hep A
- HiB
Examples of subunit vaccines (2)
- Influenza
2. Typhoid
Examples of antitoxin (2)
- Botulinum antitoxin
2. Diptheria antitoxin
When to give VZIG?
used in susceptible pregnant women neonates or immunosuppressed patients exposed to chickenpox
When to give HBIG?
Prevention of HBV infection. Used in conjunction with vaccination
When to give NHIG?
prevention of HAV, rubella and polio infection (limited efficacy)
Patients with HIV should NOT receive which virus vaccine?
a. Bacillus Calmette–Guérin (BCG)
b. Measles, mumps, rubella (MMR)
c. Hepatitis B vaccine
d. Inactivated poliovirus vaccine
e. Yellow fever vaccine
e. Yellow Fever
Whooping cough is caused by which species of bacteria?
a. Bordatella pertussis
b. Streptococcus pneumoniae
c. Corynebacterium diphtheriae
d. Corynebacterium ulcerans
e. Haemophilus influenzae
a. Bordatella pertussis
Congenital rubella syndrome (CRS)
- worst time
- manifestations (4)
first trimester
- cardiac
- auditory
- opthalmic
- neurological
Purified polysaccharide pneumococcal vaccine activates B cells to produce which sort of immunoglobulin (Ig)?
a. IgG
b. IgA
c. IgM
d. IgE
e. IgD
c. IgM
Mycobacterium tuberculosis
- description of bacteria (5)
- slow growing
- Gram + rods
- non-motile
- waxy cell wall with long-chain fatty acids
- acid alcohol fast
2 acid fast stains
- Ziehl-Neeson
2. Auramine
What colour does AFB stain with ziehl-neeson?
Red
Non-tuberculous myocobacteria
a) slow-growing (3)
b) fast-growing (3)
- source
- transmission
- association
- treatment
- M.avium
- M.marinum
- M.ulcerans
- M.fortuitum
- M.abscessus
- M.chelonae
- water & soil
- no person to person
- immunosuprression
- little response to anti-TB
M.avium
- children
- immunossuppressed
- underlying resp disease
children - pharyngitis & cervical adenitis
immunossupressed - disseminated infection
underlying bronchiectasis etc - pulmonary resembles TB
M.marinum
- who
- what
- swimming pool/aquarium owners
- single or clusters of papules/plaques over fingers/hands/elbows
M.Ulcerans
- who
- transmission
- what
- Australia
- insects
- starts as painless nodules and develops into chronic, progressive ulcer
Fast-growing non-tuberculous mycobacterium
- what
- where
- skin and soft tissue infections
- hospital-setting e.g. catheters
Leprosy “Hansen’s Disease”
- causative organisms (2)
- incubation
- transmission
- symptoms
a) skin (5)
b) nerves (2)
c) eyes (2)
d) bones (2) - treatment (3)
- types (2)
- M.leprae
- M.lepromatosis
2-10 years
nasal secretions
a) depigmentation, macules, plaques, nodules, trophic ulcers
b) thickened nerves, sensory neuropathy
c) keratitis, iridocyclitis
d) periositis, aseptic necrosis
Rifampicin, Dapsone, Clofazimine
- Paucibacillary/Tuberculoid 5 lesions
Most common opportunistic infection in HIV?
TB
Risk factors associated with TB incidence? (6)
- migrants
- IVDU
- HIV+
- homelessness
- prison
- close contacts
Which strain does BCG vaccinate against?
Efficacy?
At risk populations who receive BCG? (2)
Contraindicated?
M.bovis
80%
1. babies born in high areas of prevalence
2. unvaccinated new immigrants from high prevalence countries
HIV patients
TB Disease process (2)
- Primary TB
- infection during childhood/elderly/HIV
- asymptomatic
- granuloma present - Post-primary
- > 5 years after primary infection
- re-activation/re-infection
Risk factors for reactivation of TB? (4)
- immunosuppression
- chronic alcohol excess
- malnutrition
- ageing
Characteristic feature of TB granuloma?
Langhan’s giant cells
Progressive primary TB? (2)
- LN ulcerates into bronchus causing pneumonia
2. cavity formation causes bronchiectasis, consolidation & collapse
Miliary TB? (2)
- progressive disease
2. haematological spread
Pulmonary TB Presentation (6)
- cough
- haemoptysis
- weight loss
- fever
- night sweats
- malaise
Pulmonary TB signs (3)
- Upper lobe consolidation
- caseating granuloma
- mediastinal lymph nodes
Extrapulmonary TB
- percentage
- signs & symptoms (8)
20%
- lymphadentitis (cervical) “scrofula”
- abscesses
- pericarditis
- perotinitis
- ileitis
- skin involvement
- renal disease
- genitourinary involvement
Spinal TB
- percentage
- presentation (4)
- complications (2)
- treatment
4%
- weight loss
- fever
- sweats
- back pain
- vertebral collapse
- ileopsoas abscess
12 months anti-TB
TB Meningitis
- percentage
- presentation (8)
- investigation (2)
- treatment
2%
- headache
- weight loss
- malaise
- fevers
- sweats
- neck stiffness
- personality changes
- focal neurology
- LP - lymphocytic
- CT - tuberculomata
- 12 months anti-TB + steroids
Investigations in suspected TB
a. imaging (2)
b. cultures (3)
c. sputum stains (2)
d. histological features (4)
e. skin tests (2)
f. other (2)
a. CT, CXR
b. sputum, bronchoalveolar lavage (BAL), urine (EMU)
c. ziehl neeson, auramine
d. gram + rods, acid fast, aerobic, intracellular
e. heaf test, mantoux
f. PCR assay, IFNgamma assay
First line treatment of TB
- dosing
RIPE Rifampycin Isoniazid Pyrazinamide Ethambutol
all 4 for 2/12
Rifampycin & Isoniazid for 4/12
Side effects of Rifampycin (2)
orange secretions
hepatotoxicity
Side effects of Isoniazid (2)
peripheral neuropathy
hepatotoxicity
Side effects of Pyrazinamide (2)
hyperuricaemia
hepatotoxicity
Side effects of Ethambutol (2)
optic neuritits
visual disturbances
Treatment schedule for TB Meningitis
all 4 for 2/12
Rifampycin & Isoniazid for 8-10/12
Treatment for latent TB
6/12 Isoniazid
Second line treatment for TB? (6)
- injectables (Capreomycin, Kanamycin, Amikacin)
- Quinolones (Moxifloxacin)
- Linelozid
- PAS
- Cycloserine
- Clofazamine
Difficulties in viral selective toxicity? (2)
- viruses are obligate intracellular parasites
2. viruses use hosts enzymes for replication
How viruses are detected by the immune system? (2)
- Pattern-recognition receptors (PRRs) recognise virus
2. PRRs triggers innate immune response -> release of IFNs and restriction factors
Types of anti-viral therapy (3)
- Selective toxicity
- Immunomodulation
- Direct-acting antivirals
Which ONE of the following statements about antiviral therapy is correct?
a. Directly-acting antiviral drugs are the only effective treatments
b. Supportive treatment is of no benefit
c. Immunomodulation (e.g. interferon treatment) is effective against a single family of viruses
d. Reduction of immune suppression may enhance viral clearance
e. Selective toxicity cannot be achieved as viruses replicate inside host cells
d. Reduction of immune suppression may enhance viral clearance
Which strains of Herpes Simplex Virus are responsible for genital warts?
HSV-2 (80%)
What strain of HSV is responsible for cold sores (herpes lapialis)?
HSV-1
Herpes Simplex Encephalitis
- signs and symptoms
- no seasonal occurance, sporadic
- Fits, fevers, Funny behaviour
- Meninginism - headache, photophobia, neck stiffness, fever
VZV
- presentation in children
- presentation in adults
- seasonal occurrence
- infectivity
- complications (2)
- generalised vesicular rash over trunk, face and arms
- lesions of different stages papules/ulcers/blisters
- dermatomal distribution not crossing midline
- lesions are of similar stage
Spring/summer
1-2days before rash onset until all lesions have crusted over
- pneumonitis
- disseminated infection
Treatment of HSV/VZV (3)
- mode of action
“Act Very Fast”
Acyclovir
Valaciclovir
Famiclovir
- target viral-encoded enzymes; thymidine kinase and DNA polymerase
Always treat VZV/HSV if… (4)
- pregnant
- immunocompramised
- adults with pneumonitis
- eye involvement
Treatment of orogenital HSV
a) single episode
b) normal
c) immunocompramised
Single episode - supportive
ACV 500mg x5 daily 5/7
vACV 500mg BD 5/7
Double dose in immunocompramised
Treatment of VZV
a) normal
b) immunocompramised
ACV 800mg x5 daily 5/7
vACV 1G tds 5/7
Immunocompramised
IV ACV 10mg/kg 8hrly 5-7/7
Treatment of HSV encephalitis
IV ACV 10mg/kg 8hrly 14-21/7
The following statements are about treatment of herpesvirus infections. Choose the best answer.
a. Oral ganciclovir is recommended to treat recurrent herpes genitalis
b. Valaciclovir is recommended to treat HSV encephalitis
c. IV aciclovir is recommended to treat uncomplicated chickenpox
d. Valaciclovir is an oral pro-drug of aciclovir
e. Famciclovir is an oral pro-drug of aciclovir
d. Valaciclovir is an oral pro-drug of aciclovir
Concerning the mode of action of aciclovir (ACV), which ONE of the following statements is correct?
a. ACV directly inhibits viral thymidine kinase
b. ACV is triphosphorylated by host cell kinase
c. ACV directly inhibits viral DNA polymerase
d. ACV is triphosphorylated by viral thymidine kinase
e. ACV is monophosphorylated by viral thymidine kinase
e. ACV is monophosphorylated by viral thymidine kinase
A 42-year-old lady is admitted with a 2 day history of fever and confusion and presents with new onset seizures. What antiviral medication should she receive as soon as possible? Choose the best answer.
a. Oral aciclovir
b. IV foscarnet
c. Oral valaciclovir
d. IV ganciclovir
e. IV aciclovir
e. IV aciclovir
CMV
- what? (5) PERCH
- where does it remain latent?
- histology
- common age groups affected (2)
- common association
PERCH Pneumonitis Encephalitis Retinitis Colitis Hepatitis
monocytic cells, can reactivate in immunosupression
Owls eye inclusions or nuclei of infected cells
- children 1-4 yrs
- > 65 yrs
CMV infection after solid organ transplant or BMT
EBV
- transmission
- age group commonly affected
- causes
- signs (2)
- association
- salivary
- early teens
- Glandular fever
1. exudative pharyngitis
2. atypical lymphocytosis - Burkitts lymphoma in immunosuppressed
Treatment of CMV (3)
- Ganciclovir
- Cidoflovir
- Foscarnet
Mode of action of Ganciclovir
monophosphorylated by viral protein kinase, nucleoside analogue
Mode of action of Cidoflovir
di/triphosphorylated by cellular enzymes, nucleoside analogue
Mode of action of Foscarnet
- use
- inhibits nucleic acid synthesis without requiring activation
- Prophylaxis post-organ transplant
Universal prophylaxis for all post-transplant patients?
Ganciclovir
Side effect associated with Ganciclovir?
bone marrow supression
The following statements concern the antiviral treatment of cytomegalovirus (CMV) infection. Choose the best answer.
a. No treatment is required for uncomplicated infection
b. IV ganciclovir should always be given
c. IV aciclovir is effective
d. Oral valganciclovir OD should be used initially
e. IV foscarnet is highly myelosuppresive
a. No treatment is required for uncomplicated infection
Which of the following statements concerning the antiviral treatment of cytomegalovirus (CMV) infection is NOT correct?
a. IV ganciclovir is effective
b. Oral foscarnet is effective
c. IV cidofovir is effective
d. Maintenance therapy with oral valganciclovir can be used
e. Ganciclovir can cause neutropenia
b. Oral foscarnet is effective
When to treat CMV? (4)
- Congenital
- immunocompramised
- pregnancy
- HIV
What organism causes sixth disease in children?
- presentation (3)
- complication
HHV-6 1. high fever +/- convulsions 2. coryzal symptoms 3. sudden rash "exanthum subitum" PINK / RED, MACULAR, CAN BE RAISED PATCHES, NON-ITCHY - HHV-6 encephalitis
Exanthum subitum is associated with what disease?
Sixth Disease
Which organism is associated with Karposi’s sarcoma?
HHV-8
Presentation of Karposi’s Sarcoma?
multiple raised red/violet macules
Types of Karposi’s Sarcoma, who & prognosis (4)
- Classical - middle aged men - indolent
- Endemic - Africa - aggressive
- Iatrogenic - immune suppression - atypical location
- HIV - widespread - aggressive
Treatment of HHV - 8
- Ganciclovir
- Foscarnet
- Cidofovir
Pathogenesis of drug resistance to Acyclovir?
Which organism?
Second-line?
- Thymidine kinase mutation
- DNA polymerase mutation
HSV
Foscarnet
Cidofovir
Pathogenesis of drug resistance to Genciclovir?
Which organism?
Second-line?
- Protein kinase mutation
- DNA polymerase mutation
CMV
Foscarnet
Cidofovir
The following statements concern resistance to antiviral drugs. Choose the best answer.
a. Resistance of HSV to aciclovir is common
b. Genotypic resistance testing is routinely used to detect resistance of CMV to ganciclovir
c. Aciclovir resistance in HSV is most commonly mediated by mutations in the viral thymidine kinase
d. Aciclovir resistance in HSV is most commonly mediated by mutations in the viral DNA polymerase
e. Aciclovir-resistant HSV may be treated with ganciclovir
c. Aciclovir resistance in HSV is most commonly mediated by mutations in the viral thymidine kinase
Which ONE of the following statements concerning the treatment of influenza is NOT correct?
a. Oseltamivir is effective for influenza B
b. Oral zanamivir is effective
c. Antiviral treatment can be given before the diagnosis is confirmed
d. Amantadine is NOT effective for influenza A
e. Supportive treatment is indicated for uncomplicated influenza
b. Oral zanamivir is effective
The following statements concern the antiviral drugs oseltamivir and zanamivir. Choose the best answer.
a. Oseltamivir directly inhibits the influenza neuraminidase
b. Zanamivir blocks binding of viral haemagglutinin to host cell sialic acid
c. Oseltamivir inhibits influenza virus uncoating
d. Zanamivir is usually given intravenously
e. Zanamivir is usually given by nebuliser
a. Oseltamivir directly inhibits the influenza neuraminidase
A 82-year-old lady is in A&E on Christmas Eve with a 4 day history of fever, cough, myalgia and breathlessness. Her respiratory rate is 50 / min and her SaO2 is 88% when breathing air. In addition to empirical antibiotic therapy, what other drug(s) might be indicated right now? Choose the best answer.
a. Oral amantadine
b. Oral oseltamivir
c. Zanamivir dry powder inhaler
d. IV ribavirin
e. Oral ibuprofen
b. Oral oseltamivir
Commonest virus causing bronchiolitis?
RSV
Which ONE of the following statements regarding RSV bronchiolitis is correct?
a. Palivizumab is effective for treatment
b. Oral ribavirin is effective for treatment
c. Oseltamivir is effective for treatment
d. Supportive treatment is of no benefit
e. Palivizumab may be effective for prevention
e. Palivizumab may be effective for prevention
Side effects of Foacarnet and Cidofovir?
nephrotoxic
Treatment basis for HBV? (3)
- Serum HBC DNA levels > 2000IU/ml
- Serum aminotransferase levels > upper limit
- Liver biopsy - grade/stag e- active necroinflammation or fibrosis
Complications of uncontrolled HBV? (2)
- cirrhosis
2. HCC
First-line HBV treatment (3)
- Entecavir
- PegIFN alpha 2a
- Tenofovir
Mode of action Entecavir
nucleoside analogue, inhibits viral polymerase
Mode of action Tenofovir
inhibits reverse transcriptase
Combination treatment of HCV? (3)
- PegIFN alpha 2a
- PegIFN alpha 2b
- Ribavirin
What is included in Antenatal Booking appt (12/40) Serological Screening? (5)
- HIV
- HBV
- Syphilis
- Rubella
+/- toxoplasmosis and VZV
Most concerning time for Rubella infection during pregnancy?
Classical triad of Congenital Rubella Syndrome (CRS)? Additional features (4)
- Sensorineural deafness
- Eye defects - cataracts, congenital glaucoma, pigmentary retinopathy
- congenital heart defects - PA stenosis, PDA
- purpura
- splenomeglay
- microencephaly
- mental retardation
Clinical presentation of rubella? (4)
Investigations (2)
- fever
- rash
- occipital lymadenopathy
- myalgia
- serology - seroconversion to rubella IgG
- PCR from throat swab or blood culture
Which ONE of the following is NOT part of routine antenatal serological screening:
a. HIV
b. Syphilis
c. Hepatitis B
d. Rubella IgG
e. Measles IgG
e. Measles IgG
Which ONE of the following is NOT a typical finding in congenital rubella syndrome:
a. Congenital heart disease
b. Cataracts
c. Retinopathy
d. Limb deformity
e. Sensorineural deafness
d. Limb deformity
Complications of CMV infection during pregnancy to the unborn baby? (2)
- suspicious features of USS? (6)
- virus detection?
- congenital infection?
- developmental delay
- congenital abnormalities
- growth restriction
- hepatosplenomegaly
- ventriculomegaly
- cardiac defects
- microcephaly
- cerebral calcification
Virus detection: saliva, urine, blood, amniotic fluid
Congenital infection: urine or saliva for PCR in 1st 21 days of life
HSV routes of infection during pregnancy (3)
- direct contact during vaginal birth
- ascending infection PROM
- orolabial transmission - kissing baby
High risk time of acquisiation of HSV?
3rd trimester
The following statements concern cytomegalovirus (CMV) infection in pregnancy. Choose the best answer.
a. Antenatal ganciclovir is recommended for prevention of congenital CMV
b. Diagnosis of congenital CMV in the neonate can be confirmed by PCR of a urine specimen taken in the 1st 21 days of life
c. Congenital CMV infection is usually produces symptoms in the neonate from birth
d. Congenital CMV infection is a rare infectious cause of developmental delay
e. CMV infection in pregnant women is usually symptomatic
b. Diagnosis of congenital CMV in the neonate can be confirmed by PCR of a urine specimen taken in the 1st 21 days of life
The following statements concern genital herpes (HSV) in pregnancy. Choose the best answer.
a. Delivery by Caesarean section is recommended for a woman with primary HSV who is 35 weeks pregnant
b. Delivery by Caesarean section is recommended for a woman with a history of recurrent genital herpes with genital ulcers present during labour
c. The risk of neonatal HSV in an infant born to a mother with untreated recurrent genital HSV is high
d. Oral valaciclovir is recommended as prophylaxis against recurrent genital HSV in pregnancy
e. Neonatal herpes is nearly always caused by HSV-2
a. Delivery by Caesarean section is recommended for a woman with primary HSV who is 35 weeks pregnant
Management of primary HSV infection during pregnancy? (4)
- lesion swab PCR
- Offer acyclovir treatment and prophylaxis until delivery
- Recommend C-section if presenting within 6/7 of delivery or active lesion during labour
- Swabs from neonate & neonatal IV acyclovir empirically until ruled out infection
Time of increased maternal morbidity due to VZV in pregnancy?
2nd and 3rd trimester
Features of Congential Varicella Syndrome (3)
- gestation CVS occurs?
- limb hypoplasia
- microencelphaly
- scarring
Risk to fetus during 7days before and 7 days after birth with VZV?
Neonatal Varicella
severe disseminated infection
Management of pregnant woman exposed to VZV with no previous infection?
VZIG up to 10/7 after contact
What is the causative organism in Fifth’s Disease?
Parvovirus B19
Presentation of Fifth’s Disease? (4)
“Slapped Cheek Disease”
- fever
- rash - erythema infectiosum
- arthropathy
- aplastic anaemia
Gestation most at risk to Parvovirus B19?
Effects on fetus? (3)
Treatment?
1-20/40
- fetal death
- fetal anaemia
- hydrops fetalis
intrauterine transfusion
Which ONE of the following patients is at greatest risk of infection with varicella-zoster virus (VZV)?
a. A healthy term infant born to a mother who develops shingles the day after delivery
b. A pregnant woman born in the UK exposed to her own child who has confirmed chickenpox
c. An 18 month old child with no previous history of chickenpox whose mother has developed shingles affecting her face
d. A pregnant woman who recalls having chickenpox as a child who works in a nursery and has been exposed to multiple children with probable chickenpox
e. A pregnant woman who says she has never had chickenpox whose long-term partner has developed cold sores
a. A healthy term infant born to a mother who develops shingles the day after delivery
Which ONE of the following patients does NOT need to receive varicella immunoglobulin (VZIG)?
a. A confirmed VZV-susceptible pregnant woman whose own child developed a widespread vesicular rash 3 days ago
b. An infant born to a mother who herself develops chickenpox 4 days after delivery
c. A pregnant woman with an unknown history of chickenpox whose partner developed shingles affecting the face 10 days ago
d. An infant born at 30 weeks gestation to a mother with confirmed VZV-IgG in the serum, who is on the neonatal unit where a member of staff looking after the infant has developed chickenpox
e. A pregnant woman with an unknown history of chickenpox who has heard from a colleague that someone at her workplace had shingles last week
e. A pregnant woman with an unknown history of chickenpox who has heard from a colleague that someone at her workplace had shingles last week
The following statements concern parvovirus B19 (B19V) infection. Choose the best answer.
a. Reinfection with B19V does not occur
b. Asymptomatic B19V infection in the 1st 20 weeks of pregnancy poses minimal risk to the fetus
c. There is no intervention to reduce harm to the fetus from maternal B19V infection
d. Maternal B19V infection may result in fetal anaemia
e. B19V-IgM is a reliable indicator of primary B19V infection
d. Maternal B19V infection may result in fetal anaemia
Increased risk of vertical transmission of HBV (2)
Not a risk factor
- Maternal viral load
- HBeAg positivity
- breastfeeding, mode of delivery
HBsAg positive mother, how to manage baby after birth?
Accelerated HBV vaccine, 1st dose within 12 hours of delivery
HBeAg positive mother, how to manage baby after birth? (2)
- Accelerated HBV vaccine, 1st dose within 12 hours of delivery
- HBIG at birth
HBV viral load > 10*6 copies, how to manage baby after birth? (3)
- Accelerated HBV vaccine, 1st dose within 12 hours of delivery
- HBIG at birth
- Antenatal antiviral therapy 6-8weeks before birth to reduce viral load
Maternal influenza infection, risks to fetus? (2)
- stillbirth
2. preterm delivery
A pregnant woman is found to have hepatitis B surface antigen (HBsAg) detected in her booking serum. What should be the plan for treatment? Choose the best answer.
a. The woman should receive hepatitis B immunoglobulin
b. The infant should receive hepatitis B immunoglobulin at birth
c. The infant should receive hepatitis B vaccine at birth
d. The infant should receive lamivudine at birth
e. The woman should receive tenofovir therapy from 34 weeks gestation
c. The infant should receive hepatitis B vaccine at birth
A woman who is 34 weeks pregnant presents to A&E during the winter with a 2 day history of fever, myalgia, tachypnoea and cough. The following statements concern her management. Choose the best answer.
a. A viral throat swab should be taken and she should receive paracetamol
b. A viral throat swab should be taken and she should receive oseltamivir
c. She should be offered the current seasonal influenza vaccine
d. She should be reassured that there is no risk to her baby
e. A viral throat swab should be taken and arrangements made to call her with the result the following day
b. A viral throat swab should be taken and she should receive oseltamivir
Risk of measles to unborn fetus? (3)
- miscarriage
- preterm delivery
- increased maternal morbidity
Congenital infections transmissable from mother?
Presentation of fetus
TORCH
T - Toxoplasmosis Other - Parvovirus B19, Syphilis, VZV, HBV, HIV R - Rubella C - CMV H - HSV
T - Thrombocytopenia Other - ears, eyes R - Rash C - Cerebral abnormalities H - Hepatosplenomegaly
Common causative organisms of surgical site infection? (3)
- Staph aureus
- E.coli
- Pseudomonas aeruginosa
Risk factors for surgical site infection? (8)
- age >75yrs
- underlying illness
- obesity
- smoking
- DM
- steroid use
- radiotherapy
- RA - stop DMARDs 7-8weeks before surgery
Preventative measures to reduce risk of SSI pre-operatively? (4)
- showering with soap
- hair removal with electrical clippers, and only if necessary
- nasal decontamination of S.aureus
- Abx prophylaxis
Preventative measures to reduce risks of SSI intra-operatively? (3)
- Cleaning skin with chlorhexidine
- Normothermia
- Oxygenation
Pathogenesis of Septic Arthritis? (5)
- organism adheres to synovial fluid
- organism multiplies in synovial fluid
- triggers host inflammatoy response
- host produces fibronectin to which the organisms stick
- proteases and cytokines can causes cartilage destruction and bone loss
- increased intra-articular pressure can hamper blood flow and can cause bone ischaemia and necrosis
Most common causative organism in septic arthritis?
Staph aureus (46%) - has receptors to fibronectin
Clinical features of septic arthritis? (4)
1-2 week history of
- red
- hot
- swollen joint
- febrile
Investigations in septic arthritis? (4)
- Blood culture prior to Abx
- joint aspirate for MC+S
- CRP/ESR
- Imaging - effusion
Treatment of septic arthritis? (2)
- if MRSA?
- Drainage
- Abx 6weeks Flucloxacillin/Cephalosporin
Abx Vancomycin
Osteomyelitis
- route of infection (2)
- presentation (3)
- investigations (3)
local or haematogenous spread
- fever
- pain
- swelling
- blood culture
- MRI
- CT with biopsy
Associated with chronic osteomyelitis?
- management
Brodie’s abscess
Radical debridement, remove sequestra, remove infected tissue & bone
Prosthetic Joint Infection
- route of infection? (2)
- presentation (4)
- investigations (3)
- management
local or systemic bacteraemia (UTI)
- pain
- pt complains that “joint was never right”
- early failure of joint
- sinus tract
- imaging - loosening
- inflammatory markers
- joint aspiration
Replace joint using abx impregnated cement
Common sites of hospital acquired infections (3)
- GI
- UTI
- SSI
Common causative organisms of hospital-acquired UTI? (4)
- risk factors
- resistance
Gram neg
- E.Coli
- Klebsiella
- Pseudomonas
- Proteus
- in-swelling catheter
- extended spectrum beta-lactamases
Common Abx associated with C.diff infection? (3)
3 C’s
Clindamycin
Cephalosporins
Ciprofloxacin
Predisposing factor to C.diff diarrhoea? Transmission of C.diff... Treatment a) moderate b) severe
Existing gut flora distrubed by use of broad spectrum Abx
C diff is a spore forming anaerobe, spores are very transmissible, contaminate environment and persist for long periods
STOP Abx
a) Metronidazole 10-14/7
b) Vancomycin 10-14/7
Risk associated with C.diff?
pseudomembranous colitis due to toxins produced by c.diff
Route of infection of MRSA
skin-breach e.g. invasive procedure, skin disease, skin lesions
Steps of PCR (4)
Use of PCR
- DNA is denatured
- Primer is annealed to DNA
- DNA is exponentially multiplied by DNA polymerase starting chain elongation
- New strand and template are separated by melting
DNA of unknown virus can be probed and amplified to detect virus
What is latent infection?
When the host has lifelong infection of a virus, but during the latent period only a small subset of viral genes are expressed
Viruses that causes a latent infection in the host? (5)
- HSV
- VZV
- CMV
- EBV
5 HHV
HSV and VZV site of latency?
sensory nerve ganglia
EBC and CMV site of latency?
leucocytes
Complications of HSV in immunocompramised? (2)
- cutaneous dissemination
2. visceral involvement e.g. hepatitis, oesaphagitis
Complications of VZV in immunocompramised? (2)
- hepatitis
2. pneumonitis
Complication associated with CMV infection in HIV+ pt?
CMV retinitis
Complication associated with CMV infection in HSCT pt?
CMV pneumonitis
Complication associated with EBV infection in HIV+ pt? (2)
- Oral hairy leukoplakia
2. Lymphomas
Complication associated with EBV infection in post-transplant pt?
Management (2)
Post-transplant lymphoproliferative disease (PTLD)
- control of proliferation in latently infected B cells is lost
- Reduce immunosuppression
- Rituximab
Complication associated with Paediatric post-BMT?
Presentation (6)
Disseminated Adenovirus infection
- Fever
- Bone marrow suppression
- Haemorrhagic crisis
- Necrotising pneumonitis
- Hepatitis
- Colitis
Which one of the following statements is not true?
A.CMV pneumonitis has a poor prognosis
B. CMV infection can cause bone marrow suppression
C. Aciclovir is the treatment of choice of CMV infection
D. CMV can be transmitted from the graft
E. CMV is a herpes virus that establishes latency in B lymphocytes
C. Aciclovir is the treatment of choice of CMV infection
It’s Ganciclovir
An HIV infected patient presents with skin lesions resembling Kaposi Sarcoma, what is the causative virus?
HHV-8
A patient who received a stem cell transplant 2 weeks ago presents with mouth ulcers. Which of the following viral PCRs would you request on the mouth swab? A. Enterovirus PCR B. Adenovirus PCR C. HSV PCR D. HHV6 PCR E. HHV8 PCR
A. Enterovirus PCR
C. HSV PCR
What virus causes progressive multifocal leukoencephalopathy?
JC virus
Which of the following viruses are associated with lymphoma? A. CMV B. Adenovirus C. HHV8 D. JC E. EBV
C. HHV8
E. EBV
Complications of measles in immunocompramised patient? (2)
Fatal
- encephalitis
- giant cell pneumonia
Please examine the following hepatitis B serology results, which profile is consistent with past hepatitis B infection?
A. HBV sag (+), HBV core ab (+), HBV sab (-)
B. HBV sag (-), HBV core ab (-), HBV sab>100mIU/ml
C. HBV sag (-), HBV core ab (-), HBV sab (-)
D. HBV sag (-), HBV core ab (+), HBV sab of 15mIU/ml
D. HBV sag (-), HBV core ab (+), HBV sab of 15mIU/ml
A patient who received a stem cell transplant recently has a transaminitis. What investigations would you request on blood? A. EBV serology B. Hepatitis B surface antigen C. Hepatitis C PCR D. Hepatitis E PCR E. CMV serology
B. Hepatitis B surface antigen
C. Hepatitis C PCR
D. Hepatitis E PCR
Toxoplasmosis association
Cats faeces
Common causative organisms in early onset sepsis (3)
- GBS
- E.Coli
- Listeria
Maternal risk factors for early onset sepsis? (5)
- PROM
- Fetal distress
- Mec
- Fever
- Previous hx
Fetal risk factors for early onset sepsis? (8)
- birth asphyxia
- acidosis
- resp distress
- low BP
- hypoglycaemia
- neutropenia
- jaundice
- hepatosplenomegaly
- rash
Investigations in early onset sepsis? (7)
FBC Throat Swab Deep ear swab Surface swabs CSF CRP CXR
Management of early onset sepsis? (4)
- ABC approach
- Ventillation
- Nutrition
- Abx BenPen + Gentamycin
Amoxicillin/Ampicillin if Listeria
Causative organism in late (>48hrs) onset sepsis? (4)
- Staphylococcal
- GBS
- E.Coli
- Listeria
Presentation in late onset sepsis (9)
Bradycardia Apnoea Poor Feeding Abdo distension Irritability Convulsions Jaundice Resp distress HIGH CRP
Investigations in late onset sepsis? (6)
FBC CRP Cultures Swabs from any infected areas ET secretions if ventilated Urine
Management in late sespis
a) hospital
b) community
a) Fluclocacillin + Gentamycin
b) Amoxicillin + Cefotaxime
Pyrexia of Unknown Origin definition
Fever higher than 38.3º C on several occasions, persisting without diagnosis for at least 3 weeks in spite of at least 1 weeks investigation in hospital
Commonest cause of fever in returning traveller?
Malaria
Causes of fever in the returning traveller? (10)
Malria Dengue Typhoid Rickettsia Bacterial diarrhoea UTI Pneumonia HIV seroconversion Brucella Viral haemorrhagic fevers
What is Rickettsia?
Where is it common?
"Spotted Fever" Gram -ve bacteria Zoonose Rocky Mountains USA India
Organism associated with unpasteurised milk?
Brucella
What is Sixth Disease?
- causative organism
- presentation
- site of latency
“Roseola Virus”
HHV-6
fever, 3/7, transient rash “exanthum subitum
lymphocytes
Infectious Mononucelosis
- what is it?
- causative organism
- triad
- investigations
Glandular fever EBV 1. fever 2. pharyngitis 3. lymphadenopathy Paul Bunnel Test Monospot Agglutination
Types of PUO (4)
Classical PUO
Health-care associated PUO
Neutropenic PUO
HIV-associated PUO
Differentials in classical PUO? (7)
Definition
> 3/7 in hospital with investigations or > 3 OP visits with ambulatory investigation
- infection
- malignancy incl myeloma
- CTDs
- Abscesses
- IE
- TB
- Complicated UTIs
Differentials in Healthcare associated PUO? (6)
- SSI
- Drugs
- Medical devices - catheters, IV line bacteraemia
- LRTI
- C.diff colitis
- Immobilisation - bed sores
Differentials in Neutropenic PUO? (6)
- Chemotherapy
- Haematologiucal malignancies
- Fungal
- Bacterial
- Mycobacteria
- GVHD
Differentials in HIV associated PUO? (9)
- Seroconversion
- TB
- Karposi’s Sarcoma
- Bacterial
- PCP
- CMV
- Cryptococcus
- Toxoplasmosis
- Lymphoma
Clinical features of Typhoid/Enteric Fever? (7)
- fever
- headache
- abdo pain
- diarrhoea/constipation
- rose spots
- bradycardia
- hepatosplenomegaly
Causative bacteria in eneteric fever?
Transmission?
Salmonella typhi/paratyphi
Food and water
Rose spots are associated with?…
Enteric Fever
Eosinophilia in the returning traveller?
worms
What is malaria spread by?
Female Anopheles mosquito
Types of malaria? (4)
Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
Most severe malarial species?
P.falciparum
Investigations for suspected malaria (3)
Thick and thin blood film FBC - raised WCC - low platelets - anaemia LFTs - deranged
Benign malarial species?
P.malariae
Symptoms of malaria?
Common (7)
Uncommon (4)
Common flu-like symptoms fever rigors myalgia N&V headache back pain
Uncommon diarrhoea Abdo cramps Cough Dark urine
Blood film findings in P.falciparum? (2)
young trophozoites (rings) Crescent-shaped gametocytes
Blood film findings in P.vivax (2)
Schuffner’s dots
Merozites/Schizont
Blood film findings in P.ovale?
Schuffner’s dots
Treatment of mild P.falciparum? (3 options)
- Quinine + Doxycycline/Clindamycin
- Malarone
- Riamet
Treatment of severe P.falciparum? (2 options)
- Quinine + Doxycycline/Clindamycin
2. Artemisin Combination therapy
Treatment of P.vivax/P.ovale?
Chloroquine then Primaquine
Complications in Falciparum Malaria? (9)
Impaired conciousness Renal impairment Acidosis Hypooglycaemia Pulmonary oedema Spontaneous bleeding/DIC Anaemia Shock Haemoglobinuria
Infective Endocarditis
infection of the innermost layer of the heart, usually the valves
Most common areas for vegetations in IE?
Mitral valve
Aortic Valve
Risk factors associated with IE? (7)
- IVDU
- Poor dentition
- Rheumatic Fever
- congenital heart disease
- Valve replacement
- Long term lines
- GI issues
Acute symptoms in IE? (9)
fever malaise anorexia weight loss rigors night sweats chest pain SOB weakness
Dukes Criteria for IE Diagnosis
- 2 major criteria
- 1 major + 3 minor criteria
- 5 minor criteria
Major Criteria for IE (3)
- persistant bacteraemia > 2 positive blood cultures
- ECHO - vegetation seen
- Serology - postivive for Bartonella/Coxiella/Brucella
Minor Criteria (7)
- predisposing risk factor
- fever >38*C
- high CRP
- evidence of immune complex formation (Janeway lesions, splinter haemorrhages)
- vascular phenomena (stroke, PE)
- positive ECHO that doesn’t meet major criteria
- positive serology that doesn’t meet major criteria
Signs of subacute IE? (7)
clubbing splinter haemorrhages Osler's nodes Janeway lesions Roth spots Splenomegaly Haematuria
Investigations in IE? (9)
FBC - aneamia U+Es CRP - high ESR - high x3 blood cultures BEFORE Abx ECHO CXR Serology Urine analysis
Common causative agent in subacute endocarditis?
Onset
Strep viridans
mild - moderate illness
Common causative agent in acute endocarditis?
Onset
Staph aureus
days - weeks
Unusual causes of IE? HACEK
H - haemophilus parainfluenzae A - aggregatibacter/actinobacillus C - caridobacterium hominis E - eikenella corrodens K - kingella kingae
Right sided IE is common in who? Why?
IVDU, inject into venous system, bacteria goes into SVC into R side of the heart
Treatment of IE in prosthetic valve?
Vancomycin + Gentamycin + Rifampicin
Treatment of acute IE in native valve?
FLucloxacillin
Treatment of subacute IE?
Benzylpenicillin + Gentamycin
What is a zoonose?
pathogenic diseases and infections that are transmitted naturally between vertebrate animals and humans
Brucellosis
- carriers (4)
- incubation
- transmission (2)
- who is at risk? (2)
- symptoms (5)
- complications (2)
- treatment
dogs, goats/sheep, cattle pigs 3-4 days direct contact or contaminated food e.g. unpasteurised dairy vets, farm workers 1. undulant fever 2. malaise 3. sweats 4. rigors 5. myalgia
- carditis
- osteomyelitis
Tetracycline/Doxycycline with Streptomycin
Rabies
- carriers (2)
- transmission
- pathognomonic histology
- prodrome (3)
- acute symptoms (2)
- management
- dogs, bats
- bite
- Negri bodies
- headache, fever, sore throat
- acute encephalitits, hyperactive state, fear of water
- rabies IgG post-exposure
Plague
- causative organism
- carriers
- transmission
- types (2)
- treatment
Yersinia pestis fleas on rats flea bites human 1. Bubonic - flea bites human 2. Pulmonary - human to human spread during epidemic Streptomycin/Doxy/Gent/Chloramphenicol
Leptospirosis
- causative organism
- transmission
- who is at risk?
- symptoms (6)
- complications (3)
- treatment
L.interrogans spirochaetes excreted in dog/rat urine, penetrates broken skin in contaminated water swimmers 1. headache 2. spiking temp 3. conjunctival haemorrhages 4. jaundice 5. malaise 6. myalgia
- carditis
- renal failure
- haemolytic anaemia
Amoxicillin
Cutaneous anthrax presentation
painless round black lesions with rim of oedema
Pulmonary Antrax presentation (4)
- lymphadenopthy
- mediastinal haemorrhage
- pleural effusion
- resp failure
Lyme Disease
- transmission
- where
- causative agent
- three stages
- diagnosis
- treatment
tick bite woodland/gardens/parks Borrelia burgdo 1. Early localised 2. Early disseminated 3. Late persistant biopsy + ELISA for Lyme Abs Doxycycline
Symptoms of early localised Lyme Disease? (3)
- Erythema Chronicum Migrans (ECM) “Bullseye Rash”
- non-specific flu-like symptoms
- cyclical fevers
What is erythema chronicum migrans associated with?
Lyme Disease
Symptoms of early disseminated Lyme Disease (6)
- malaise
- lymphadenopathy
- hepatitis
- carditis
- arthritis
- palsies
Symptoms of late persistent Lyme Disease? (4)
- Arthritis
- focal neurology
- neuropsychiatric distrubance
- acrodermatitis chronic atrophicans
What is acrodermatitis chronic atrophicans?
widespread atrophy of the skin most evident peripherally at first
Q fever
- causative organism
- vectors (2)
- presentation (5)
- treatment
Coxiella burnetti cattle/sheep 1. fever 2. dry cough 3. fatigue 4. pleural effusions 5. diarrhoea Doxycycline
Leishmania - vector - transmission - where? types of infection (4)
- sandfly
- bite from sand fly
- South & Central America, Middle East
1. Cutaneous
2. Diffuse Cutaneous
3. Muco-cutaneous
4. Visceral
Presentation of cutaneous Leischmania?
Type of hypersensitivity reaction?
skin ulcer at site of sandfly bite, heals after a year leaving a deep depigmented scar
Type IV
Who gets diffuse cutaneous Leischmania?
immunocompramised
Lots of nodules
What are prion diseases?
rare, transmission encephalopathies in humans and adults, caused by protein-only infectious agents
cause rapid neuro-degeneration in animals and humans
How does the prion embed in the brain? (3)
Prion protein gene is expressed on chromosome 20, predominantly expressed in the brain
Normal PRP structure is alpha-helical, but the infected PRP abnormally fold into beta-sheet configuration and becomes insoluble
What is the commonest form of prion disease?
a. Kuru
b. Iatrogenic CJD
c. Gerstmann-Straussler-Sheinker syndrome
d. Variant CJD
e. Sporadic CJD
e. Sporadic CJD
Features found of post-mortem in Sporadic CJD? (2)
- spongiform vaculation
2. PrP amyloid plaques
Sporadic CJD
- onset
- presentation (5)
- prognosis
45-75 years
- rapid, progressive dementia
- myoclonus
- cortical blindness
- akinetic mutism - inability to move or speak
- LMN signs
18 yr old woman
LLL pneumonia
Unwell
Raised WCC + CRP
What is the likely organism?
a. Pseudomonas aeruginosa
b. Mycobacterium tuberculosis
c. Legionella pneumophilia
d. Streptococcus pneumoniae
e. Staphylococcus aureus
d. Streptococcus pneumoniae
56 yr old man
LLL pneumonia
Haemoptysis
Cavitiation on CXR
What is the likely organism? A) Streptococcus pneumoniae B) Haemophilus influenzae C) Staphylococcus aureus D) Klebsiella pneumoniae E) Any of the above
B) Haemophilus influenzae
62 yr old smoker
Confused
Bilateral interstitial change
Hyponatraemic
what is the likely organism?
a. Moraxella catarrhalis
b. Mycobacterium tuberculosis
c. Legionella pneumophilia
d. Cytomegalovirus (CMV)
e. Staphylococcus aureus
c. Legionella pneumophilia
What is the probable diagnosis? 74 year old woman RLL pneumonia On standard Abx Not getting better
a. Tuberculosis
b. Empyema
c. Mesothelioma
d. MRSA pneumonia
e. Aspiration pneumonia
b. Empyema
21 yr old from Ecuador
Cough and weight loss
RUZ shadowing on CXR
What is the likely organism?
a. Staphylococcus aureus
b. Aspergillus fumigatus
c. Mycobacterium tuberculosis
d. Haemophilus influenzae
e. Pneumocystis jiroveci
c. Mycobacterium tuberculosis
64 yr old man
Treated for TB
CXR shows bilateral ground-glass shadowing
What is the likely organism?
A) Aspergillus fumigatus B) H1N1 Swine flu C) Mycoplasma pneumoniae D) Cytomegalovirus (CMV) E) Pneumocystis jiroveci
E) Pneumocystis jiroveci
22 year old man
Chemotherapy for leukaemia
Prolonged neutropenia (
b. Aspergillus
Pneumonia
- what
- presentation (7)
- assessment of severity
inflammation of lung alveoli
- fever
- cough
- sputum
- SOB
- pleuritic chest pain
- fever
- malaise
- N&V
CURB65
What is the CURB65 score?
Confusion
Urea >7nmol
RR >30
BP 65yrs
Most common organisms causing CAP?
- Step pneumoniae
2. H.influenzae
Strep pneumoniae pneumonia
- where in the lungs?
- microscopy
- sputum colour?
lobar
gram+ve diplococci
rust-coloured sputum
H.influenzae pneumonia
- associated with who? (3)
- common sign
- microscopy (2)
- smokers
2, pre-existing lung conditionse.g. COPD - kids aged
M.catarrhalis pneumonia is associated with who?
smokers
Common cause of HAP?
Staph aureus
Staph. aureus pneumonia
- association
- EMQ
- sign on CXR?
- microscopy
- previous viral infection
- post-influenza
- cavitation on CXR
- Gram +ve cocci “bunch of grape” clusters
Klebsiella pneumoniae
- association (2)
- common sign
- sign on CXR
- microscopy
- alcoholics
- elderly
haemoptysis
cavitation on CXR
Gram -ve rod
First line treatment of moderate CAP?
Amoxicillin or Erythromycin/Clarithromycin if Pen allergic
Treatment of sever CAP?
Augmentin + Erythromycin/Clarithromycin
Common cause of atypical pneumonia in paediatrics?
Mycoplasma pneumoniae
Legionella pneumonia
- who in EMQ
- association (3)
- presentation (4)
- clinical features (3)
- culture requires?
- travelling business men
1. travel
2. air conditioning
3. water towers
- SOB
- Confusion
- Abdo pain
- diarrhoea
- hepatitis
- HYPOnatremia
- lymphocytopenia
buffered charcoal yeast extract
Mycoplasma pneumonia
- who
- where
- presentation (2)
- specific test
- complications (2)
- children 6months - 5 years
- Mexico
1. erythema multiforme
2. joint pain - cold agglutinin test
- SJS
- AIHA
Signs associated with chlamydia pneumoniae?
ENT involvement
Chlamydia psittaci
- who?
clinical symptoms (3)
BIRD FANCIERS
- hepatosplenomegaly
- rash
- haamolytic anaemia
Causative agent of whooping cough?
Who is at risk?
Bordatella pertussis
Unvaccinated e.g. travelling community
Treatment of atypical pneumonias? (2)
why?
Macrolides and Tetracyclines that work on protein synthesis because atypical organisms do not have a cell wall
Pneumonias that HIV-patients are susceptible to? (3)
- P.jiroveci/Pneumocystis carinii pneumonia
- TB
- Crytococcus neoformans
P.jiroveni/PCP
- sign on CXR?
- onset
- diagnosis (2)
- microscopy
- ground-glass shadowing
- insiduous
1. Silver stain
2. immunofluorescence - boat-shaped organisms
Common cause of pneumonia in chemotherapy patients with neutropenia?
- presentation (2)
- clinical feature
Fungus - Aspergillus
- bronchiectasis
- chronic wheeze
- eosinophilia
Common cause of pneumonia in BMT patients? (2)
- Aspergillus
2. CMV
Caustaive organisms of pneumonia in splenoectomy patients? (3)
- H.influenzae
- S.pneumoniae
- Neisseria meningitidis
ENCAPSULATED BACTERIA
Common cuase of pneumonia in CF patients? (2)
- Pseudomonas aeruginosa
2. Burkholderia cepacia
What is bronchitis?
- presentation (4)
- association
treatment (3)
- SOB
- increased sputum production
- cough
- fever
smokers
- Physiotherapy
- broncodilation
- Abx
Diagnostic test used in severe CAP?
Urine antigen tests to look for
S.pneumoniae
Legionella
Causative organism in cat scratch disease?
Bartonella henselae
A man was bitten by a rat in Asia. Ten days later he complains of fever, malaise, headache and myalgia
Haverhill Fever
caused by Spririllum minus
A zoonosis associated with hepatitis, jaundice, conjunctival injection and renal impairment. Transmission normally occurs by direct contact with either the urine or tissues of an infected animal.
Leptospirosis
A 45 year old male farmer presents with a raised, erythematous rash, with clearing in the centre. He also complains of headache, fever, athralgia and malaise
Borrelia burgdoferi
Lyme disease
A 22 year old student presented to her GP upon return from a biology field trip, with a lesion on her leg which was 3” in diameter and flat, with a red edge and dim centre. She also mentioned feeling tired and suffering from headaches. On examination, the GP noted a fever of 38.0°C and an irregular heartbeat.
Borrelia burgdoferi
Lyme Disease
A tanner on holiday from India presented to hospital with an ulcerating papule on his hand. On inspection of the ulcer, the centre was black and necrotic. Gram-positive rods grew on blood agar culture and responded to treatment with large doses of penicillin.
Bacillus anthracis
A 21 year old man presents at his GP complaining of an itchy, scaly rash on the soles of his feet. Skin scrapings are taken and sent away for microscopic examination. Which fungi might be identified?
Tricophyton rubrum -> tinea pedis
A 17 year old Nigerian girl presents at her GP with patches of hypopigmentation on her trunk. After an initial trial of steroid cream, the girl returns complaining that the rash is spreading. Woods lamp examination of the rash produces a yellow fluorescence. What is the causative fungus?
Pityriasis orbiculare
A 45 year old female whose main hobby was pigeon racing was noted by her GP to an enlarged lymph node in her neck. What is the most likely diagnosis?
Cryptococcus neoformans, is a pathogenic fungus commonly found in pigeon droppings and pigeon nests (and also soil). The predominant clinical process usually in immunocompromised pts, is a variably subacute meningitis with occasional patients showing features of brain abscess or inflammatory cerebral vasculitis, so the clinical feats are usually - headache, fever, nausea, neck stiffness, feats of raised ICP. Histoplasmosis, is also spread from bird droppings -but apparently not so specific to pigeons. Disseminated histoplasmosis, as you correctly state can cause lymphadenopathy (resembles disseminated TB - fever, weight loss, lymph nodes). PS. Remember India Ink staining for cryptococcus, which is often a clue in questions.
Superficial fungae (2) - diagnosis
- Tinea
- Pityriasis
- Wood Lamp
Causative organism in Athlete’s foot?
- yeats or mould?
Tricophyton rubrum
mould
Causative organism in seborrhoeic dermatitis?
yeats or mould?
Malessezia furfur
mould
Causative organism in Tinea versicolor?
- presentation
- yeast or mould
Malessezia globosa
depigmented lesiosn in darker skin
mould
Deep-seated fungae (3)
- Candida
- Aspergillus
- Crytococcus
How to diagnose Candida infection? (2)
- yeast or mould?
- Culture
- Mannan Antibodies
yeast
Aspergillus
- yeats or mould?
- who
- associated
- diagnosis (3)
yeast immunocompramised patients HCC 1. ELISA 2. PCR 3. beta-Glucan test
Crytococcus
- yeast or mould?
- who?
- type of infection
- where
- diagnosis (2)
- yeast
- immunocompramised
- meningitis with insidious onset in HIV patients
- pigeon poo
1. Cryptococcal antigen in serum
2. CSF
Mode of action of Amphotericin?
- type of fungus
- use
interupts cella membrane integrity
Yeast
Crytptococcus meningitis
Mode of action of Azoles?
- type of fungus
- use
- e.g.
interupy cell membrane synthesis
yeast
candida
fluconazole
Mode of action of Terbinafine?
- type of fungus
- use
targets cell membrane
mould
Tinea
Mode of action of Echinpcandin?
- type of fungus
- example
targets cell wall
yeast
Caspofungin
STIs causing discharge (5)
- Gonorrhea
- Chlamydia
- Trichomonas
- Candida
- BV
STIs causing ulceration (5)
- Syphilis
- HSV
- LGV
- Chancroid
- Donovanosis
STIs causing rashes/lumps/growths (4)
- HPV
- Molluscum contagiosum
- Scabies
- Pubic lice
Painful ulcers…
Herpes > Chancroid
Painless ulcers…
Syphilis > LGV + granuloma inguinale
Causative organism in opthalmia neonatorum (neonatal conjunctivitis) & microscopy (2)
- Neisseria gonorrhoeae
Gram negative diplococcus - Chlamydia trachomatis
Gram negative
Gonorrhoea
- presentation in men (3)
- presentation in women (6)
Men - urethral discharge - dysuria - scrotal pain/swelling Women - vaginal discharge - itching/soreness - erythema/oedema - abdo pain - dyspareunia
Gonorrhoea
- transmission
- who is at risk? symptoms (3)
- diagnosis
- treatment
- sexual
- during vaginal delivery through birth canal
complement deficiencies - disseminated gonococcal infection
- septicaemia
- rash
- arthritis
Urethral/rectal smears
Ceftriaxone IM/ Cefixime PO
Complications of Gonorrhoea
a) Men
b) Women
a) prostatitis
b) PID -> infertility
Which chlamydia serovars cause trachoma?
Serovars A, B, C
infection of the eyes which can lead to blindness
Which chlamydia serovars cause genital chlamydia infection and opthalmia neonatorum?
Serovars D - K
Chlamydia
- who
- causative organism
- presentation
- complications in women (7)
- complication in men (3)
- diagnosis
- treatment
younger population, in the UK 10%
Side effects of azithromycin (2)
Contraindicated & why? (2)
- N&V
- photosensitivity
Pregnancy
bone growth disturbance & tooth discolouration in babies
What is Reiters Syndrome?
- triad
- who gets it?
- conjunctivitis
- urethritis
- arthritis
young men with chlamydia trachomitis infection
What is LGV?
Lympho-granuloma venereum
Lymphatic infection with chlamydia trachomatis
Which chlamydia serovars cause LGV?
L1, L2, L3
EMQ land who commonly gets LGV?
- developing world
- MSM
Presenting features of LGV?
a) early day 3-12 primary stage
b) late week 2-25 secondary stage
c) late
d) current outbreak
a) PAINLESS genital ulcer
b) PAINFUL buboes (inguinal abscesses)
c) inguinal lymphadenopathy, rectal strictures/fistulas
d) rectal symptoms - pain, tenesmus, bleeding, discharge
Treatment of LGV?
Doxycycline BD 3 weeks
Causative organism in Syphilis?
Treponema pallidum
Gram negative spirochaete
Common co-infection with syphilis?
HCV
The course of syphilis? Primary Secondary Latent Tertiary
Primary - indurated painless ulcer appears 1-12 weeks following transmission
Secondary - systemic bacteraemia within 6 months following transmission
Latent - no signs but serological infection
Tertiary - years after transmission
Primary syphilis features
PAINLESS indurated genital ulcer
often solitary
can persist for 4-6weeks -> chancre
regional lymphadenopathy
Secondary syphilis features (9)
- low grade fever
- malaise
- symmetrical, non-pruritic, widespread maculo-papular rash
- mucosal “snail track” mucosal lesions
- uveitis
- choroidoretinitis
- alopecia
- genital warts “condyloma acuminate”
- neurological involvement
Latent syphilis
no obvious signs, but serological infection
Tertiary syphilis 3 types (3)
- Granuloma/Gumma
- Cardiovascular
- Neurosyphilis
Features of Gumma Syphilis (3)
- onset
- type of reaction
- skin
- bone
- mucosa
2-40 years later
delayed hypersensitivity reaction
Features of cardiovascular syphilis
- onset
aortitis
+++ inflammation
10-30 years later
Features of neurosyphilis (4)
- onset
- who is most at risk?
- CSF findings
- type of reaction
- pathgnomonic
- meningovascular
- general paresis of the insane
- tabes dorsalis
- gumma
- 2-30 years later
- HIV +ve
- spirochaetes
- small vessel vasculitis
- Argyll-Robertson pupil
What is tabes dorsalis?
Slow degeneration of the nerves of the dorsal column leading to loss of proprioception/fine touch/vibration
What is an Argyll-Robertson pupil?
What is it pathgnomonic of?
pupil can accommodate to near objects but does not constrict in bright light
Neurosyphilis
Treatment of Syphilis?
- side effects
IM Benzathine Penicillin
Doxycyline is Pen allergic
Jarisch-Heimer reaction - fever, headache, myalgia, exaccerbation of syphilic features
Congenital syphilis
- transmission
- features (5)
during pregnancy or birth
- fever
- rash
- hepatosplenomegaly
- neurosyphilis
- pneumonitis
Chancroid
- what
- presentation (2)
- causative organism
- diagnosis
- treatment
bacterial tropical ulcer disease multiple painful genital ulcers , painful lymphadenopathy Haemophilus ducreyi chocolate agar plate Azithromycin
Donovanosis
- causative organism
- where in the world (3)
- presentation (3)
- diagnosis
- treatment
Klebsiella granulomatis
- India
- Africa
- Australia aborigines
- expanding ulcers
- start as papule/nodule then break down
- beefy red appearance
- Giemsa stain showing Donovan bodies
- Azithromycin
Tichomoniasis
- causative organism
- presentation in men
- presentation in women
- associated risk
- treatment
trichomoniasis vaginalis asymptomatic or urethritis green malodorous discharge increased risk of HIV Metranidazole
Bacterial vaginosis
- what
- presentation
- diagnosis (3)
- complications (2)
change in vaginal flora, polymicrobial odour, discharge - MC + S - raised pH - clue cells
- preterm delivery
- often recurrent
Candidiasis
- causative organsim
- presentation in women (5)
- presentation in men
- treatment (2)
- association
candida albicans
- vulvovaginitis
- thick white discharge
- itchiness
- redness
- soreness
- Clotrimazole
- Fluconazole
immunosuppressed
Molluscum contagiosum
- causative agent
- who? (2)
- where? (2)
- transmission
- treatment
Pox virus a) children - hands and face b) adults - genital lesions skin to skin contact cryotherapy
Genital warts
- causative agent
- which strains?
- presentation (6)
- incubation
- treatment
- contraindication
HPV
6 and 11
Warts
- papular
- planar
- pedunculated
- carpet
- keratinised
- pigmented
3 weeks -> 8 months
Podophyllotoxin
pregnant women
The antiviral which is given to untreated pregnant women with HIV to prevent vertical transmission of the virus during childbirth.
Nevirapine
A drug that is effective against influenza A but not influenza B
Amantidine