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Liv Path > Mirco: Resp, Gastro and Infective Endocarditis > Flashcards

Mirco: Resp, Gastro and Infective Endocarditis Flashcards

1
Q

S. Pneumonia

A

+ve diplococci
a-haemolytic

Rusty-coloured sputum. Usually lobar on CXR. Almost always penicillin sensitive.

30-50% CAP

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2
Q

H. influenzae

A

-ve cocco-bacilli

Smoking, COPD

15-35% CAP
More common with pre-existing lung disease.
May produce beta-lactamasde.

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3
Q

M. catarrhalis

A

-ve coccus

Smoking

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4
Q

S. aureus

A

+ve cocci in “grape-bunch clusters”

Recent Viral Infection (post influenza infection in EMQs), ± cavitation on CXR

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5
Q

K. pneumoniae

A

-ve rod

Alcoholism, Elderly, haemoptysis

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6
Q

Legionella pneumophila

A

Travel, Air Conditioning, Water towers, Hepatitis, Low sodium
Can cause multi-organ failure

Confusion, abdo pain, diarrhoea. Lymphopenia and hyponatraemia.

Dx - urinary antigens

Requires special culture: buffered charcoal yeast extract

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7
Q

Mycoplasma pneumonia

A

Common – systemic symptoms, joint pain, cold agglutinin test, erythema multiforme. Risk SJS, AIHA

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8
Q

Chlamydia pneumonia

A

Hard to diagnose

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9
Q

Chlamydia psittaci (psittacosis)

A

Birds - inhalation

Splenomegaly, rash, haemolytic anaemia

Dx by serology

Sensitive to macrolide

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10
Q

Bordatella pertussis

A

Whooping cough in unvaccinated – (often travelling community in EMQs)

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11
Q

Rx - Classical mild-moderate pneumonia

A

Penicillin e.g Amoxicillin or macrolide if pen allergic (5-7 days)

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12
Q

Rx - Classical moderate-severe pneumonia

A

Penicillin + Macrolide ( e.g Co-amoxiclav + Clarithromycin) (2-3 weeks)

Allergic: Cefuroxime AND clarithromycin.

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13
Q

Rx - Classical HAP

A

1st Line: Ciprofloxacin ± Vancomycin

2nd Line/ITU: Piptazobactam + Vancomycin (ITU pts increased risk of resistant bacteria/MRSA)

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14
Q

Rx - HAP - Pseudomonas

A

Piperacillin+tazobactam (tazocin/piptazobactam) or Ciprofloxacin ± Gentamicin

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15
Q

Rx - HAP - MRSA

A

Vancomycin

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16
Q

Rx - Atypical Pneumo - Chlamydia, mycoplasma

A

Macrolide (e.g. Clarithromycin/erythromycin)/tetracycline (e.g. doxy)

(20% CAPs)

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17
Q

Rx - Aspiration Pneumonia

A

Cefuroxime and metronidazole

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18
Q

Rx - CAP - Legionella

A

Macrolide + rifampicin

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19
Q

Rx - CAP - S.aureus

A

Flucloxacillin

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20
Q

Score for Pneumonia Severity

A

Curb-65

Confusion
Urea >7 mmol/l
RR >30
BP <90 systolic <60 diastolic
>65 years

Score 2 = ?admit
Score 2-5 = manage as severe

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21
Q

Compromise to resp defences

A
  • Poor swallow
  • Abnormal ciliary function e.g. smoking, viral infection, kartagener’s
  • Dilated airways - bronchiectasis
  • Defects in host immunity
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22
Q

Resp Pathogens by age

A

0-1 mths- E.coli, GBS, Listeria

1-6mths- Chlamydia trachomatis, S aureus, RSV

6mths-5yrs- Mycolpasma, Influenza

16-30yrs-M pneumoniae, S pneumoniae

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23
Q

Bronchitis

A

Inflammation of medium sized airways (smaller lumen).
Mainly in smokers

S. pneumoniae
H. influenzae
M. catarrhalis

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24
Q

Coxiella Burnetii (Q fever)

A
  • Common in domestic/farm animals
  • Transmitted by aerosol or milk
  • Dx by serology
  • Sensitive to macrolides
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25
Q

Pneumonia failure to improve on treatment

A

Empyema / abscess

Proximal obstruction (tumour)

Resistant organism (incl. Tb)

Not receiving / absorbing Abx

Immunosuppression

Other diagnosis

  • Lung cancer
  • Cryptogenic organising pneumonia (type of idiopathic intersitial pneumonia w/fibrosis)
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26
Q

TB - Clues

A

Clues:

  • Ethnicity
  • Prolonged prodrome
  • Fevers
  • Weight loss
  • Haemoptysis
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27
Q

TB - CXR

A

Classically upper lobe cavitation but can vary considerably

Ghon focus/complex

Occasionally milliary

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28
Q

TB - Stains

A

Auramine and ziehl Neelsen (counter stain with methylene blue)

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29
Q

Most common causes of HAP (organisms)

A

Staphylococcus aureus - 19%
Enterobacteriaciae - 31%
Pseudomonas spp - 17%

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30
Q

Pneumocystis Jirovecii

A

Protozoan

Ubiquitous in environment

Insidious onset

Dry cough, weight loss, SOB, malaise

CXR “bat’s wing” - bilateral ground glass shadowing

Dx Immunofluorescence on BAL (bronchoalveolar lavage)

Rx Septrin (Co-trimoxazole)

Prophylaxis Septrin

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31
Q

Aspergillus Fumigatus Lung Diseases

A

Allergic bronchopulmonary aspergillosis:

  • Chronic wheeze, eosinophilia
  • Bronchiectasis

Aspergilloma:

  • Fungal ball often in pre-existing cavity
  • May cause haemoptysis

Invasive aspergillosis:

  • Immunocompromised
  • Rx Amphotericin B
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32
Q

Immunosuppression & LRTI

A

HIV: PCP, TB, atypical mycobacteria

Neutropenia: fungi e.g. Aspergillus spp

Bone marrow transplant: CMV

Splenectomy: encapsulated organisms
e.g. S. pneumoniae, H. influenzae, malaria

BUT “Anything can do anything”

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33
Q

Antigen Tests - Pneumonia

A

Limited urine antigen tests available:

  • S. pneumoniae
  • Legionella pneumophila

Send in severe community-acquired pneumonia

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34
Q

Antibody Tests - Pneumonia

A

Only useful on paired serum samples

Usually collected on presentation and 10-14 days later

Look for rise in antibody level over time

Most useful for organisms that are difficult to culture eg:

  • Chlamydia
  • Legionella
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35
Q

The only organism (pneumonia) for which immunofluorescence is routinely used

A

Pneumocystisis jirovecii

May also be detected by Silver stain in cytology lab

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36
Q

Prevention of pneumonia

A

Smoking advice

Vaccination:
- Childhood immunisation schedule.
- Adults: 
Influenza annually
Pneumovax every 5 years
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37
Q

Pulmonary TB - Sx

A

FLAWS
+/- cough
+/- haemoptysis

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38
Q

Pulmonary TB - RFs

A 
Recent Migrant
HIV
Homelessness
IVDU
Immunosuppression
Foreign travel
Living closely with people
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39
Q

Pulmonary TB - Ix

A

Imaging: CXR (Upper lobe cavitation typically). CT

Culture – Sputum (x3), bronchoalveolar lavage (BAL), urine (EMU - early morning urine), pus etc in Lowenstein-Jensen medium (Gold Standard)

Sputum microscopy – ZN/auramine staining: Gram +ve rods, acid fast, aerobic, intracellular

Tuburculin skin tests (TST): Mantoux/Heaf using PPD

IGRA: interferon-γ release assays e.g. Elispot, Quantiferon - used for screening/diagnosing latent TB NOT active.

NAAT: PCR-line probe assays, tests for sensitivities (more sensitive than culture)

Other: Liquid culture mediums

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40
Q

TB - Vaccination

A

Vaccination: BCG (=Bacille Calmette-Guerin)

Attenuated strain of M. Bovis

Efficacy 0-80% – Bad for pulmonary TB. Good for leprosy, TB meningitis, disseminated TB.

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41
Q

Extrapulmonary TB

A

All the “ITIS”

Pericarditis, Lymphadenitis, Peritonitis etc

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42
Q

TB Meningitis

A
  • FLAWS + Neurological change
  • Diagnose with CT and LP
  • Needs 1yr TB tx with Steroids (PP says 10 months?)
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43
Q

Pott’s Disease aka Spinal TB

A

FLAWS

Hematogenous spread –> initial discitis –> Vertebral destruction + collapse ± Anterior extension (causing iliopsoas abscess)

Ix – MRI/CT ± Biopsy/Aspirate

Rx – 1 year anti TB treatment

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44
Q

Pulmonary TB - Rx

A 
RIPE
6 months (pp says 4?):
Rifampicin - raised transaminases, induces CYP450, orange secretions
Isoniazid (+pyridoxine) - peripheral neuropathy, hepatotoxicity

2 months:
Pyrazinamide - hepatotoxicity
Ethambutol - visual disturbance (check colour visitant every review)

+ vit D, nutrition, surgery

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45
Q

M. Leprae & M. Lepromatosis

A

SNEB

Skin: Depigmentation, macules, plaques, nodules, ulcers

Nerves: Thickened nerves, sensory neuropathy

Eyes: Keratitis, Iridocyclitis

Bone: Periositis, aseptic necrosis

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46
Q

M. Avium (part of M avium complex with M. intracellulare)

A

Children – Pharyngitis/cervical adenitis

Pulmonary – Underlying lung disease (resembles TB)

Disseminated – Lymphoma etc

AIDS – Disseminated infection, Mycobacteraemia (consider in HIV pts with longstanding diarrhoea)

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47
Q

M. Marinarum

A
  • Single or clusters of papules/plaques –> granulomas

- Swimming pool/aquarium owners

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48
Q

M. Ulcerans

A
  • Insect Transmission / Bite
  • Early – painless nodule
  • Usually slowly progressive leading to ulceration, scarring + contractures –> Bairnsdale ulcer, Buruli ulcer
  • Seldom fatal, hideous deformity
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49
Q

MTB complex includes

A

M. tuberculosis

M. bovis

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50
Q

M. abscessus complex includes

A

M.abscessus
M.massiliense
M.bolletii

51
Q

Mycobacteria microbiology

A

Non-motile rod-shaped bacteria

Relatively slow-growing compared to other bacteria

Long-chain fatty (mycolic) acids, complex waxes & glycolipids in cell wall

  • Structural rigidity
  • Complete Freund’s adjuvant
  • Staining characteristics

Acid alcohol fast

52
Q

“Rapid Growing” NTM

A

M. abscessus, M. chelonae, M. fortuitum

Skin & soft tissue infections
- Tattoo associated outbreaks

In hospital settings, isolated from BCs

  • Vascular catheters & other devices
  • Plastic surgery complications
53
Q

NTM - RFs

A
  • Age

- Underlying illness/condition (particularly resp)

54
Q

Diagnosis of NTM

A

Lung disease
Clinical: pulmonary symptoms, nodular/cavitary opacities, multifocal bronchiectasis with multiple small nodules

Exclusion of other diagnoses

Microbiologic:

  • Positive culture >1 sputum samples
  • OR +ve BAL
  • OR +ve biopsy with granulomata
55
Q

NTM - Rx

A

Susceptibility testing results may not reflect clinical usefulness

MAI (mycobacterium avium)

  • Clarithromycin/azithromycin
  • Rifampicin
  • Ethambutol
  • +/- Amikacin/streptomycin

Rapid-growing NTM- Based on susceptibility testing, usually macrolide-based

56
Q

Close contact of a person with smear positive pulmonary TB, What is his lifetime risk of developing active TB?

A

10%

57
Q

Post-primary TB

A

Reactivation or exogenous re-infection

> 5 years after primary infection

5-10% risk per lifetime

Risk factors for reactivation

  • Immunosuppression
  • Chronic alcohol excess
  • Malnutrition
  • Ageing

Clinical presentation
- Pulmonary or extra-pulmonary

58
Q

Other Extra-Pulmonary TB

A

Lymphadenitis

  • AKA scrofula
  • Cervical LNs most commonly
  • Abscesses & sinuses

Gastrointestinal
- Swallowing of tubercles

Peritoneal
- Ascitic or adhesive

Genitourinary

  • Slow progression to renal disease
  • Subsequent spreading to lower urinary tract
59
Q

Where has the most MDR TB?

A

Russia
China
India

60
Q

Drug Resistant TB

A

Multi-drug resistant TB (MDR)- Resistant to rifampicin & isoniazid

Extremely drug-resistant TB (XDR)- Also resistant to fluoroquinolones & at least 1 injectable

Spontaneous mutation + inadequate treatment

RFs:

  • Previous TB Rx
  • HIV+
  • Known contact of MDR - TB
  • Failure to respond to conventional Rx
  • > 4 months smear +ve/>5 months culture +ve

4/5 drug regimen, longer duration - Quinolones, aminoglycosides, PAS, cycloserine, ethionamide

61
Q

Influenza A virus - Hosts

A

Many different host species - birds, pigs etc

62
Q

Influenza Tropism

A

Causes resp disease because:

1) The host cell receptor (sialic acid) the virus binds to is only expressed in the lung
2) The influenza virus can only get into the body through the mouth
3) The influenza virus requires activation by host cell proteases that are only expressed in the respiratory tract - human airway tryptase
4) The influenza virus envelope can only fuse with membranes of cells that secrete mucus.

63
Q

Host range barriers prevent infection of humans with most avian influenza, however, infection of humans with H5N1 avian influenza viruses can lead to

A

hypercytokinaemia –> ARDS

64
Q

Key Features of Pandemic Flu

A

A pandemic virus will have novel antigenicity.

A pandemic virus will replicate efficiently in human airway.

A pandemic virus will transmit efficiently between people.

65
Q

AIV (avian flu) replication in mammals can be achieved by a single amino acid change in polymerase

A

PB2 E627K

Avian influenza viruses co-opt ANP32A to support RNA replication but cannot utilize shorter mammalian ANP32 homologues unless they mutate PB2. However Reassortment/polymerase adaptation is not sufficient for evolution of a pandemic virus.

66
Q

Features of HA and NA that affect influenza transmission

A

Receptor binding
Virion stability
NA stalk length

67
Q

Genetic determinants of influenza susceptibility

A

Loss of IFITM3 linked with severe influenza.

68
Q

Antivirals for Influenza

A

Amantadine

  • Targets M2 ion channel
  • Single amino acid mutation in M2 (S31N) renders virus resistant
  • Does not work against influenza B or pH1N1 or seasonal H3N2

Neuraminidase inhibitors and mode of administration:

  • Tamiflu (oseltamivir) oral
  • Relenza (zanamivir) inhaled or iv formulation
  • Peramivir iv

Polymerase inhibitors:

  • Favipiravir (licensed in Japan excluding pregnant women)
  • Baloxavir (licensed in Japan) - inhibits the PA endonuclease (decreased virus shedding may interrupt transmission)
69
Q

Tamiflu

A

Conflicting evidence

In adults oseltamivir reduced time to first alleviation of symptoms by 16.8 hours, in children by 29 hours.

“no evidence.. to use these drugs to prevent serious outcomes in annual influenza and pandemic influenza outbreaks….”

1/2 mortality if NAI given within 48 hours of symptom onset.

70
Q

UK adult flu vaccine is

A

live attenuated

71
Q

Influenza vaccines in use today - 2 types

A

Trivalent or quadrivalent inactivated vaccine

  • Split or subunit- HA rich
  • Given to those at risk
  • Short term strain specific immunity mediated by antibody to HA head
  • Adjuvants introduced to boost response in elderly

Live attenuated vaccine, quadrivalent

  • Cold adapted virus limited to urt
  • Given to children
  • Broader more cross reactive immunity including cellular response
72
Q

Novel oil-in-water adjuvants used in monovalent vaccines AS03 Pandemrix have been associated with

A

Narcolepsy (H1N1-related)

73
Q

Clostridia - Botulinum

A

Canned/vacuum packed foods: Blocks Ach release from peripheral nerves –> DESCENDING paralysis

Descending paralysis - differentiates from GBS

Rx - antitoxin

74
Q

Clostridia - Perfringens

A

Reheated meats
Enterotoxin (super antigen) acts on small bowel, 8-16hrs incubation.
Watery diarrhea +cramps, lasts 24hrs.

Can also cause gas gangrene

75
Q

Clostridia - Difficile

A 
2 exotoxins (A,B) 
Pseudomembranous colitis (i.e an inflamed bowel) 
Caused by Abx usually cephalosporins, cipro and clindamycin

Rx - 1st line metronidazole PO, 2nd line vancomycin PO. Also infection control - need to be in side room, hand washing with soap and water (gel doesn’t kill spores)

76
Q

Bacillus cereus

A

Gram +ve rod-spores
Heat stable emetic toxin (not destroyed by reheating)

Reheated rice
4-18 hours incubation
Watery non-bloody diarrhoea + Vomiting

Self limiting
Rare cause of bacteraemia in vulnerable populations - can cause cerebral abscesses

77
Q

S. Aureus

A

Catalase and coagulase positive gram +ve coccus

Produces enterotoxin (exotoxin that acts as superantigen, releasing IL1 and IL2 –> prominent vomiting + watery, non bloody diarrhoea)

Self-limiting

78
Q

Enterotoxigenic E.coli (ETEC)

A

Travellers diarrhoea

Act on the jejeunum, ileum not on colon.

79
Q

Enteroinvasive E.coli (EIEC)

A

Invasive, dysentry (cramps, D&V)

80
Q

Enterohaemorrhagic E.coli (EHEC)

A

haemorrhagic O157:H7 EHEC: shiga- like verocytotoxin causes HUS

81
Q

Enteropathogenic E.coli (EPEC)

A

Infantile diarrhoea (paeds)

82
Q

Haemolytic uraemia syndrome

A

Anaemia, thrombocytopenia, renal failure

E.coli 0157:H7)

83
Q

E.colis - Rx

A

Self limiting - can treat with ciprofloxacin but tend to avoid abx

Source - human faeces, contaminated food/water

(Gram -ve enterobacteriacae)

84
Q

Salmonella - Typhi and Paratyphi (enteric fever)

A

Only transmitted by humans
Multiplies in Peyers patches,
Slow onset fever + CONSTIPATION, relative bradycardia
Splenomegaly and rose spots, anaemia and leukopaenia.
bacteraemia in 3% carriers.

Rx- ceftriaxone or ciprofloxacin

85
Q

Salmonella - Enteritides

A

Poultry, eggs and meat
Self limiting non-bloody diarrhoea

Rx- usually none. Ceftriaxone or ciprofloxacin (if required)

86
Q

Shigella

A

Mainly affects the distal ileum and colon –> mucosal inflammation, fever, pain, bloody diarrhoea, shiga enterotoxin

Avoid abx (cipro if required)

87
Q

Yersinia enterocolitis

A

Associated with farming/ domestic animal excreta – transmitted via contaminated food.

Enterocolitis, mesenteric adenitis w/ necrotising granulomas, assoc reactive arthritis & eythema nodosum.

88
Q

Vibriosis - Cholera

A

(comma shaped, late lactose fermenters, oxidase +ve)

Rice water stool.
Massive diarrhoea without inflammation.
cAMP: opens Cl channel at the apical membrane of enterocytes&raquo_space; efflux of Cl to lumen; loss of H2O and electrolytes

Rx - supportive

89
Q

Vibriosis - Parahaemolyticus

A

(comma shaped, oxidase +ve)

Ingestion of raw undercooked seafood (common in Japan)
3/7 of diarrhoea which is often self limiting

Rx- Doxycycline

90
Q

Vibriosis - Vulnificus

A

(comma shaped, oxidase +ve)

Cellulitis in shellfish handlers
Fatal septicaemia with D&V in HIV patients

Rx - doxycycline

91
Q

Campylobacter Jejuni

A

(curved, comma or S shaped)

Unpasteruised milk, poultry
Prodrome of headache and fever, cramps, bloody (foul-smelling) diarrhoea
**Assoc with Guillain-Barre, reactive arthritis (Reiter’s)

Only teat if immunocompromised - Erythromycin or Cipro if first 4-5/7

92
Q

Listeria Monocytogenes

A

V or L shaped, ß haemolytic with tumbling mobility

Unpasteruised dairy, vegetables
GI watery diarrhoea, cramps, headache, fever, little vomiting.

Rx - Ampicillin, Ceftriaxone, Cotrimoxazole

93
Q

Entamoeba Histolytica

A

Protozoa
EMQ: MSM
Also: food, water, soil

Colonizes colon - Makes a flask-shaped ulcer on histology
Mature cyst has 4 nuclei
Symptoms: dysentery, wind, tenesmus. Chronic weight loss + RUQ pain due to liver abscess

Stool microscopy for dx (wet
mount, iodine and trichrome)

Rx- Metroniazole + Paromomycin if luminal disease

94
Q

Giardia lamblia

A

EMQ: Travellers/hikers/MSM/ psych hospitals

Pear shaped trophozoite 2 nuclei Trophozoites/cysts found in stool
Get it by ingesting cysts from faecally contaminated H2O
Malabsorption of protein + fat - foul smelling non-bloody diarrhoea

Dx = ELISA + stool microscopy, “string test”

Rx - metronidazole

95
Q

Cryptosporidium Parvum

A

Infects the jejunum.
Severe diarrhoea in immunocompromised.

Dx = Oocysts see in stool by Kinyoun acid fast stain

Rx - Paromomycin
Nitazoxanide in kids, reconsistution of immune system

96
Q

Viruses: Secretory Diarrhoea

A

Adenovirus – Types 40,41 cause non bloody diarrhoea (<2yrs)

Rotavirus - <6yrs. dsDNA “wheel like”. Replicates in mucosa of small intestine. Secretory diarrhoea, no inflammation.

Norovirus – Adult outbreaks, vomiting.
Other

97
Q

3 organisms causing bloody diarrhoea

A

hang on a bloody SEC

Shigella
E.coli
Campylobacter

98
Q

Superantigens

MOA - secretory diarrhoea - toxin production

A

Superantigens bind directly to
T-cell receptors and
MHC molecules;

outside the peptide binding site

> > massive cytokine production by CD4 cells ie systemic toxicity and suppression of adaptive response

99
Q

Inflammatory Diarrhoea vs Enteric Fever

A

Inflammatory - exudative diarrhoea

Enteric fever - interstitial inflammation

100
Q

GI Vaccines

A

Cholera

  • Inactivated, whole cell (PO)
  • Live attenuated (PO) not recommended

Campylobacter- military, infants,traveller, candidate vaccines exist..

ETEC- inactivated and live vaccines in trials

Salmonella typhi- Vi capsular PS (IM) and (PO)live

Rotavirus - various PO options

101
Q

GI - Notifiable diseases

A

Campylobacter, Clostridium sp, Listeria monocytogenes, Vibrio, Yersinia

102
Q

UTI - Common Organisms

A

Bugs: E. coli (95%), Proteus, Klebsiella, Staphylococcus saprophyticus (frequent causes of Lower UTIs). Also enterococcus faecalis, staph epidermis.

Catheter associated UTIs is likely staph epidermis

103
Q

UTI - Diagnosis

A

Clinical, Dipstick (nitrite, leucocytes +ve), Bloods - WBCs, Neutrophils, CRP,MSU MC&S (see organism, pyuria) – beware epithelial cells.

104
Q

UTI - Rx

A

Cephalexin or nitrofurantoin

Nitrofurantoin is 1st line from NICE or Trimethoprim if low risk of resistance, but check EGFR is >45ml/min if giving Nitrofurantoin

If catheter associated - gentamicin/amikacin

105
Q

Pyelonephritis - Rx

A

If pyelonephritis – Coamox +/- Gent OR Cefuroxime +/- Gent

106
Q

Cystitis

A

inflammation of the bladder, often caused by infection

107
Q

Uncomplicated vs Complicated UTI

A

Uncomplicated urinary tract infection refers to infection in a structurally and neurologically normal urinary tract.

Complicated urinary tract infection refers to infection in a urinary tract with functional or structural abnormalities (including indwelling catheters and calculi).Generally seen in:
- Men
- Pregnant women
- Children
- Patients who are hospitalised or in health care associated settings.
There are more likely to be caused by non–E.coli organisms

108
Q

UTI - RFs

A
  • Obstruction (intra or extra renal)
  • Vesicoureteric reflux
  • Haematogenous
109
Q

Urine Microscopy - White Cells and Squamous Epithelial Cells

A

White cells Pyuria – indicative of infection

Squamous epithelial cells – indicative of contamination

110
Q

Causes of Sterile Pyuria

A 
Prior treatment with antibiotics
Calculi
Catheterisation
Bladder neoplasm
TB
Sexually Transmitted Disease
111
Q

Fungal UTI

A

Remove catheter

Don’t need to give medication

112
Q

Hep A

A
  • Acute hepatitis IP 2-6 weeks
  • Often subclinical
  • Faecal-oral spread
  • Notifiable
  • Occupational risks
  • GUM clinics
  • There is a vaccine
113
Q

Hep B - General

A
  • DNA Virus
  • Sexual
  • Vertical
  • Blood products
  • ACUTE and CHRONIC
  • Chronic = 6 months or more
  • Can lead to cirrhosis and HCC/liver failure
  • Vaccine available
114
Q

Chronic Hep B - Rx

A 
Interferon alpha
Lamivudine
Tenofovir
Entecavir
Emtricitabine
115
Q

Hep C- General

A
  • RNA virus
  • Flaviviridae
  • Mainly blood product spread
  • 60-80% chronicity
  • Natural history
  • Acute HepC: 20-40% of people clear, 60-80% chronically infected
116
Q

Acute Hep C - Rx

A 
Peginterferon alfa-2b
Combination therapy (pegylated - not cleared as quickly)
117
Q

Hep D

A

Can’t get D without B

Rx: INFa

118
Q

Hep E

A

Like Hep A, but from Indochina, can be chronic and spread via pigs
Treatment: ribavirin
Vaccine - effective
Rare complications - CNS disease – Bell’s palsy, Guillain Barre, other neuropathy, Chronic infection

119
Q

Infective Endocarditis - Duke’s Criteria

A

BE FEVER

Major - BE:

  • Bacteraeima - >2 cultures, 12 hours apart.
  • Echo findings - vegetations

Minor- FEVER:

  • Fever of >38 degrees
  • Echo findings that don’t meet the major criteria
  • Vascular phenomenon e.g. embolization, stroke, PE
  • Evidence of immune complex formation or microbiology not meeting major criteria
  • Risk factors – murmur, IVDU

2 major, 1 major & 3 minor or 5 minor for diagnosis.

120
Q

Infective Endocarditis - Presentation and RFs

A

Symptoms & Signs:

  • FLAWS
  • Chest Symptoms (SOB, tightness)
  • Janeway lesions, osler’s nodes (painful), splinter haemorrhges, roth spots (eyes)

RFs:

  • Rheumatic heart disease
  • Congenital Heart disease
  • IVDU
121
Q

Subacute Infective Endocarditis

A

Takes weeks - months

Likely Strep Viridans

122
Q

Acute Infective Endocarditis

A

Takes days - weeks

Likely Staph Aureus

Assoc with IVDU and therefore Tricuspid Valve involvement.

123
Q

Other causes of IE

A

Gm –ve HACEK organisms

H - Heamophilius species 
A - aggregatibacter species 
C - cardiobacterium species
E - eikenella corrodens
K - kingella species
124
Q

IE - Rx

A

Strep Viridans – BenPen & Gent

MSSA - Flucloxacillin

MRSA – Vancomycin +
Other

Prosthetic valve - Vanc & Gent & Rifampicin

Liv Path (24 decks)

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