ID Flashcards

1
Q

How can you distinguish between HIV dementia and Alzheimer’s disease?

A

Absence of higher cortical dysfunction such as aphasia, agnosia and apraxia, dysphagia help to distinguish from classical cortical dementia such as Alzheimer’s disease.

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2
Q

When are HIV infected patients at risk of OI and malignancy?

A

CD4 200-500: HZV, pneumococcal pneumonia, oral candidiasis, Tb

CD4 50-200: PJP, CNS toxoplasmosis, crytococcosis, kaposi’s sarcoma, NHL, PCNS lymphoma

CD4

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3
Q

Which haematology malignancy has the highest RF for developing invasive fungal infection?

A
AML
Allogenic HSCT (part cord blood as source)
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4
Q

Which transplants have the highest risk fro developing fungal infections?

A

Heart, lung and liver transplant.

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5
Q

When is the Mantoux test considered positive?

A

> = 5 mm:
HIV or risk factors, close TB contacts, CXR evidence of TB.
=10mm
Indigent/homeless, residents of endemic Tb areas, residents of developing nations, IV drug use, chronic illness, NH, prisoners and health care workers
=15 mm for all other persons, BCG vaccination

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6
Q

How do you treat P. falciparum?

A

Riamet (Artemether and lumefantrine)
Malarone (Atovaquone + Proguanil)
Quinine sulphate + doxycycline

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7
Q

How do you treat severe malaria/chloroquinine resistant?

A

IV artesunate or

IV quinine

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8
Q

How do you Tx P. vivax, ovale, malariae?

A

Chloroquinine
Follow with 14 d course of primaquine for vivax and ovale
Exclude G6PD def prior to use of primaquine

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9
Q

MOA Artemether?

A

is metabolised to the active metabolite artenimol (dihydroartemisinin). Combination with lumefantrine acts in the food vacuole of the malaria parasite interfering with the conversion of haem to nontoxic haemozoin; also inhibits nucleic acid and protein synthesis.

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10
Q

How does Typhoid present (Salomella typhi)? Spread? Tx?

A
Clinical:
Fever
Abdo pain
Constipation (not diarrhoea)
Rose spots

Spread:
Faecal oral spread, usually water borne
Consider achlorydia in chronic setting

Tx:
Ciprofloxacin
Ceftriaxone
Azithromycin

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11
Q

Which organism is the likely cause of dental disease?

A

Strep viridans

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12
Q

Which organism is the likely cause of prolonged indwelling vas catheter and IVDU?

A

S. aureus

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13
Q

Which organism is the likely cause of procedures involving gut and perineum?

A

Enterococcus faecalis

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14
Q

Which organism is the likely cause of bowel malignancy?

A

Strep bovis

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15
Q

Which organism is the likely cause of soft tissue infection?

A

Staphlococci

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16
Q

Causes of culture negative endocarditis?

A

Coxiella brunette
Bortenella
Chlamydia
Legionella

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17
Q

What are the major and minor criteria for IE?

Dx criteria

A

2 major or 1 major + 3 minor or 5 minor

Major
1. +ve BC fro IE. Typical organisms growing in 2 cultures in absence of a primary focus

  1. ECHO evidence of mass, abscess, dehiscence
  2. Positive serological test fro Q fever
  3. New valvular regurgitation
Minor
Fever>38
Vascular phenomena
Immunoogoc phenomena
Microbiological evidence
Echo findings consistent with IE but not meeting the major criteria
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18
Q

What is the Tx for syphilis in patients with a penicillin allergy?

A

Doxycycline 100 mg PO BD

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19
Q

Are penicillins effective against Mycobacterium avium complex?

A

No

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20
Q

Increased number of which interleukins are associated with critical illness?

A

IL 6, 8, 15, interleukin 12p70

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21
Q

What are the histopathological changes associated with H1N1 virus infection?

A
varying degrees of diffuse alveolar damage with hyaline membranes and septal oedema, targets aleveolar lining cells (Type 1 and 11 pneumocytes)
Tracheitis
Necrotising bronchiolitis
Pulmonary vascular congestion
Alveolar haemorrhage
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22
Q

What is the explanation for the ability of the virus to cause severe viral pneumonitis in humans?

A

Ability to increase ex-vivo replication in human bronchial epithelium at 33C

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23
Q

What is the explanation for the ability of the virus to cause severe viral pneumonitis in humans?

A

Ability to increase ex-vivo replication in human bronchial epithelium at 33C

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24
Q

Which virus is responsible for (i) pandemics and epidemics, (ii) smaller localised milder outbreaks?

A

Influenza A

Influenza B

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25
Q

What is the pathophys of H1N1 virus?

A

The enzyme neuraminidase (N) present on the viral envelope facilitates cell penetration and the release of replicated viruses from the cell surface.

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26
Q

Influenza:
Localised outbreaks due to?
Epidemic and pandemic due to?
The annual influenza epidemics is best explained by which mechanism?

A

Localised outbreaks:
Antigenic drift in H and N influenza (local - A and B)

Epidemics and pandemics:
Antigenic SHIFT in H and N proteins (Influenza A).

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27
Q

What mechanism explains the new influenza A subtypes?

A

Antigenic SHIFT

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28
Q

List the gram +ve cocci

A

Staph
Enterococci
Strep

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29
Q

List the gram –ve cocci

A

Nessierua menin + gono

Moraxella

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30
Q

List the gram +ve bacilli (ABCDL)

A
Actinomyces
Bacillus
Clostridium
Diptheria
Listeria
Remaining organisms are gram –ve bacilli (rods)
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31
Q

Which mutation in viral neuraminadase confers high level resistance to oseltamavir?

A

His275Tyr mutation

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32
Q

What is the likely cause of vancomycin resistance in enterococci?

A

Changes in cell wall to prevent binding

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33
Q

What is the mechanism of resistance of H. influenza?

A

production of beta lactamase

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34
Q

Do patients with a PFO require abx prophylaxis prior to Sx?

A

no

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35
Q

Which patients with cardiac conditions require IE abx prophylaxis before Sx ?

A

A prosthetic heart valve
Valve repair with prosthetic material
A prior history of infective endocarditis
Many congenital (from birth) heart abnormalities, such as single ventricle states, transposition of the great arteries, and tetralogy of Fallot, even if the abnormality has been repaired

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36
Q

What is the most common fungal infection in immunocompromised pts?

A

Candida

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37
Q

What is the mortality rate of invasive aspergillus infections in immunocompromised patients? What are the RF?

A
94%
Neutropenia > 21d
CMV
GVH
Corticosteroids
RTx
Diagnosis by PCR for Aspergillus. -ve pcr has high NPV
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38
Q

What is the Tx for MAC?

A

Ethambutol
Rifampicin
Clarithromycin

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39
Q

Do you get a rash with malaria?

A

no

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40
Q

When does the rash typically start for dengue?

A

3 days

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41
Q

Aetiology of dengue?

A

Flavavirus spread by the mosquito Aedes agyptii

Incubation of 3-14 d

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42
Q

What are the 3 syndromes of Dengue?

A

Classic

  • abrupt fever, severe back pain, transitory maculopapular rash.
  • defervescence and recrudescence of fever

Dengue haemmorhagic fever

  • fever lasting 2-7 d
  • hemorrhagic manifestation e.g. positive tourniquet test or spontaneous bleeding
  • thrombocytopenia, Plts
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43
Q

What is the Mx of dengue?

A

Supportive

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44
Q

What are the lab findings for Dengue?

A
  • neutropenia
  • thrombocytopenia
  • increased transaminases
  • diagnosed by dengue serology (4 x rise in antibody titre over 2 weeks)
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45
Q

Main causes of fever in a returned traveller?

A

Dengue - rash
Malaria - no rash
Typhoid (S. typhi) - a type of enteric fever along with paratyphoid fever

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46
Q

Aetiology of Malaria?

A

Transmitted by female mosquito

P. falciparum- most common, most severe and highest mortality
P. vivax
P. ovale
p. malariae - benign
P. knowlesi - hyperparasitemia
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47
Q

How do you Dx Malaria?

A

Thick and thin films
Immunochromatographic test (ITC)
Antigen capture test - rapid diagnosis. High sensitivity for P. falciparum if > 100 parasites/uL
haemolytic anaemia

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48
Q

What is the Tx for P. viviax, oval and malaria?

A

chloroquine/hydroxychloroquine

Primaquine as anti-relapse therapy for 14 days after chloroquine

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49
Q

Tx for P. vivax chloroquine resistant?

A

Riamet (Arthemether-lumafantrine) 1st line in Indonesia, Timor, PNG, Solomon island and Vanuatu

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50
Q

What is the Tx for P. falciparum?

A

1st line- Riamet (Arthemether-lumafantrine)
2nd line - Malarone (Artovaquone and Proguinil)
3rd line - Quinine and doxy

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51
Q

What is the Tx for severe Malaria (jaundice, reduced LOC, anaemia, pulmonary odema, hypoglycaemia))?

A

IV artesunate

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52
Q

What is the Tx for malaria in pregnancy?

A

quinine and clindamycin

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53
Q

Chemoprophylaxis for Malaria (chloroquinine resistant or sensitive)?

A

Chloroquinine sensitive, use chloroquinine

Chloroquinine resistant, use atovoquone and proguinil

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54
Q

How do you Dx Schistosomia haematobium? What is it?

A

Trematode, found in Africa or middle east.

Eosinophilia - hallmark of disease

Stool culture - ova detected (at 40-50d of infection)
Urine culture - ova detected (at 40-50 d of infection)

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55
Q

Clinical presentation of Schistosomia haematobium?

A
fever
chills
cough
urticarial rash
hepatomegaly
lymphadenopathy
haematuria
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56
Q

Tx of Schistosomia haematobium?

A

Praziquantel

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57
Q

What causes Leptospirosis? How does it present? Dx? Tx? Complications?

A

Spirochete leptospira interrogans
fever, chills, myalgia, diarrhea, conjunctival suffusion
Dx- leptospira serology
Tx- amoxycillin, doxycline or Ceftriaxone
Complications- hemorrhage, jaundice, acute renal failure, aseptic meningitis

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58
Q

What is the most common cause of diarrhoea in an adult traveller to a developing country?

A

Enterotoxigenic E. coli (ETEC)

40-70% of traveller’s diarrhoea

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59
Q

Causes of watery diarrhoea?

A

ETEC
Vibrio cholera
Viral

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60
Q

Causes of bloody diarrhoea?

A

Shigella
Slamonella
Campylobacter
Entameba histolytica

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61
Q

Causes of prolonged diarrhoea?

A

Giardia

Crypto

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62
Q

What is the Tx of traveller’s diarrhoea, mild and mod?

A

Mild - fluids +/- loperamide

Mod- single dose azithromycin or single dose oral norfloxacin

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63
Q

Organism responsible for typhoid? Geographic location? Incubation period? Clinical presentation? Tx?

A

Salmonella typhi/paratyphi
Common in India, Vietnam, SE Africa, middle east
Incubation 7-21 d
Fever, abdo pain, CONSTIPATION, Rose spots.
Ceftriaxone 2g IV or azithro 1 d OD if India or Vietnam
Cipro 500 mg BD for 7-10d if outside India/Vietnam

64
Q

What is chronic salmonella in stool or urine for > 1y associated with?

A

Gallbaldder Ca

65
Q

Tx of Giardia?

A

Tinidazole

66
Q

Returned traveller with prolonged hx of diarrhoea. Dx?

A

Giardia

67
Q

Clinical presentation of Entamoebe histolytica (amoebic abscess? Geography? Tx?

A

Fever, RUQ pain, diarrhoea
Usually presents 8-20 weeks
Returned traveller from Africa
Tinidazole and paromomycin

68
Q

Life threatening fungal infection requiring urgent surgical debridement? where is the origin of the infection usually? Tx of refractory disease?

A

Zygomycosis caused by zygomycetes
May affect GI or skin and usually begins in the nose and parasinuses
prone to disemmination
Liposomal amphotericin B

69
Q

Antifungal Tx consist of?

A

Fluconazole
Echinocandins
Amphotericin B

70
Q

Is fluconazole effective against candida krusei?

A

No

71
Q

Dx of aspergillus fumigata?

A

Culture
Bx
Galactomannan ELSA
- Moderate accuracy for Dx in immunocompromised patients
- galactomanan is the major constituent in the cell wall, released during growth of hyphae
PCR assays

72
Q

Tx of Aspergillus fumigata?

A

1st line - Voriconazole

2nd line - amphotericin

73
Q

Tx of TB?

A

2 months of rifampicin, isoniazid, ethambutol and pyrazinamide followed by 4 months of rifampicin and isoniazid.

74
Q

Which TB drug is associated with a high rate of mono resistance?

A

Isoniazid

75
Q

Which strategy has most effectively reduced the incidence of infections with multi-resistant TB in a population?

A

Directly observed Tx with short course therapy

76
Q

Organism associated with Endocarditis in dental disease, soft tissue infections, gut malignancy, prolonged indwelling vas catheter/IVDU and procedures involving gut and perineum.

A
Dental - strep viridians
soft tissue infections - Staph species
Gut malignancy - strep bovis
Prolonged vas cath/IVDU - Stap aureus
Procedures involving gut and peritoneum - Enterococcus faecalis
77
Q

What investigation abnormalities due you expect in advanced HIV infection?

A
Decrease in
- CD4
- CD4:CD8 ratio
-NK cells
Increase in
-CD8 suppressor/cytotoxic T-cells
- B cells spontaneously secreting immunoglobin
78
Q

Treatment for a patient with severe community acquired pneumonia and history of immediate hypersensitivity to penicillin?

A

Moxifloxacin. 10% chance of hypersensitivity to cephalosporins.

79
Q

Treatment for pt with MRSA pneumonia not responding to Vancomycin and deteriorating?

A

Linezolid. Inhibits protein synthesis and action against many gram positives including E. faecalis

80
Q

What is the most common life threatening hospital infection?

A

HAP

10 to 20% of patients who are on ventilators for longer than 48 hours

81
Q

What is the most common cause of recurrent bacterial meningitis?

A

Head trauma
The majority of patients in whom meningitis develops as a complication of closed head trauma have a basilar skull fracture, which causes the subarachnoid space to be connected to the sinus cavity and is associated with an increased risk of infection.
Mean time is 11 days from injury to onset of meningitis.
Leakage of cerebrospinal fluid is the major risk factor

82
Q

What is the best screening test for syphilis?

A

T. pallidum enzyme immunoassay (EIA).
Detects both IgM and IgG antiboides which as the earliest tests to be positive
A positive test is confirmed with TPHA/PAA

83
Q

In patients with HIV and TB, when should HIV Tx commence?

A

CD4 count = 50 and severe clinical disease, initiate Tx within 2-4 weeks of starting TB Tx

CD4 count >=50 who do not have severe clinical disease -> can be delayed 2-4 weeks but must be started within 8-12 weeks of starting TB Tx

84
Q

Why is Rifabutin the preferred rifamycin to use in HIV infected pts with active TB on a PI based regime?

A

The risk of substantial drug interactions with PIs is lower with Rifabutin than with Rifampin

85
Q

Should ART and TB Tx be continued in a pt with Immune reconsititution Inflammatory Syndrome?

A

Yes

86
Q

When should TB Tx commence in HIV infected pregnant women with active TB?

A

As early as feasible

87
Q

Can Interferon Gamma Release Assay (IGRA) distinguish between active and latent TB?

A

No

88
Q

What is the Tx of choice in a pt with pneumococcal meningitis with a penicillin allergy?

A

Vanc + Cipro

Alternative is moxiflox as single agent

89
Q

For what dental procedures is endocarditis prophylaxis required?

A

Extraction
Periodontal procedures including Sx, sub gingival scaling and root planning
Replanting avulsed teeth
Apicoectomy (root end Sx)

90
Q

Fever in returned traveller. DDx?

A
Malaria
Typhoid and paratyphoid
Dengue fever
Anmoedbic liver abscess Hepatitis
Respiratory infections
STI, HIV
Schistosomiasis
91
Q

Most common abx causing C. diff?

A

Amoxycillin

92
Q

What Ix findings suggest an empyema?

A

pH

93
Q

What is associated with C. diff infection as vs. colonisation?

A

NAP1 strain - more virulent strain, may occur without abx use

94
Q

What is the most common arbovirus illness transmitted world wide?

A

Dengue fever, transmitted by mosquitos A. aegypti.

95
Q

What is the most common manifestation of chronic Q fever infection?

A

Endocarditis

96
Q

What si the Tx for outpt Community MRSA?

A

Clindamycin

97
Q

What is schistosomiasis? Dx? Tx?

A

Infection with trematode/fluke
Intermediate host is a snail releases circariae in fresh water
Dx - eggs in stool or urine
Tx- Paziquantel

98
Q

What is the MOA of multi drug resistant gram negative bacteria?

A

Genes coding resistance located in the plasmid of bacteria

99
Q

Which antimicrobials cause cardiac complications e.g. prolong QT?

A

Macrolides - azithro, clarithro, erythro
Azoles - voriconazole >fluconazole
Fluoroquionolones - ciproflox, levoflox, nalidixic

100
Q

Resistance to which antimicrobial agent is the strongest predictor of MDR TB?

A

Rifampacin

101
Q

What does MDR TB, XDR TB mean? Tx?

A

MDR - Resistance to 1st line agents rifampicin and isoniazid
XDR - MDR resistance plus resistance to one fluoroquinolone and one injectable e.g. amikacin
1st line - RIPE/HRZE
2nd line - fluoroquinolone, aminoglycasies, thionamides (ethionamide, prothionamide), cycoserine, PAS, capreomycin

102
Q

List the live vaccines.

A
M - MMR
O - Oral polio
B - BCG
Y - Yellow fever
Je - lmojev
V - varicella
R - rotavirus
T - oral typhoid
103
Q

The 4 Cs in measles? Dx? Complications of Measles?

A

Prodrome of cough, coryza, conjunctivitis and Koplik spots for 3-4 days then one of rash that progresses inferiorly starting at the head (Face->neck->trunk->limbs
Symptoms start 10 days after exposure.
Dx - IgM standard test
Complications - pneumonia, ADEM (scute dissemminated encephalomyelitis)

104
Q

What is the 1st line therapy for candidaemia?

A

Echinocandins e.g. anindulafungin

105
Q

Which type of gastro can be sexually acquired?

A

Shigella

106
Q

What is the most common cause of aseptic meningitis? If there is sexual exposure, what cause should be considered?

A

Enterovirus most common

HSV2 if sexual exposure

107
Q

What is the Tx for P falciparum and P-vivax in non severe malaria?

A

Artemether - lumefantrine

108
Q

What infection is should be considered in an indigenous person with Hodgkin’s lymphoma commenced on RCHOP and develops fever, vomiting, haemoptysis, infiltrates on CXR and eosinophilia? Tx

A

Strongyloides

Ivermectin 200 mcg/kg OD

109
Q

Which yeast appears as gram +ve on gram stain?

A

Cryptococcus

110
Q

Who should receive rabies post exposure prophylaxis? What is the prophylaxis?

A

If you have been exposed to rabies, even if no symptoms

Vaccine IM day 0,3,7,14 and HRIG up to 7 days after the first vaccine

111
Q

What is the classic presentation of typhoid?

A

Returned traveller that did not seek prertavel medical advice, ate local food, no precautions.
Fevers, headache, abdo pain, bradycardia, rose spots

112
Q

Which infections in returned travellers cause a rash?

A

Dengue
Chikungunya
Typhoid
Strongyloides

113
Q

Pt with HB sAb +ve, HB sAg -ve and HBV cAb +ve for Tx with Rituximab. Next step?

A

Antiviral Tx with entecavir or lamivudine

114
Q

Tigecycline is effective against pseudomonas? T/F

A

False, intrinsically resistant

Polymyxins (clinsitn and polymixin) are usually the cornerstones for therapy

115
Q

Causes of negative nitrite in urine dip stick despite culture positive UTI?

A

insufficient bladder incubation time for conversion of nitrate to nitrite
low urinary excretion of nitrate
Inability of some organisms to convert nitrate to nitrite e.g. enterococcus faceless and decreased urine pH (due to cranberry juice or other dietary supplements)

116
Q

What is the reason for adding Clindamycin to penicillin in the Tx of necrotising faciitis?

A

Anti-toxin effects against toxin-elaborating strains of streptococci and staph and MRSA

117
Q

What is the empiric Tx for endocarditis? What organism are covered?

A

Ceft, Flucolox, Gent

Cover staph, strep and enterococci

118
Q

Pt is on van and meropenem but continues to spike temperatures. What abx would you consider adding?

A

Fluconazole for candidaemia

119
Q

What is the rationale for using combinations in HIV protease inhibitors? MOA Ritonavir

A

Ritonavir component inhibits the CYP3A metabolism of lopinavir -> increased plasma levels of lopinavir

120
Q

MOA of lopinavir?

A

Binds to the site of HIV-1 protease activity nd inhibits the cleavage of viral Gag-Pol polyprotein precursors into individual functional proteins required for infectious HIV -> formation of immature noninfectious viral particles.

121
Q

How does toxoplasmic encephalitis present on imaging? LP? Tx?

A

Ringed enhancing lesions +/- mass effects

Increased OP
CSF -ve gram stain

Tx
Pyrimethamine-sulphadiazine with folinic acid
Add steroids if mass effect

122
Q

Which infections are Corticosteroid are beneficial/not beneficial?

A
Beneficial:
Severe typhoid
Hib meningitis in children
Croup
Tb leprosy
Severe pneumocystis pneumonia
Tb meningitis
Tb pericarditis
Type 1 lepra reaction
Katamaya fever
No benefits:
Meningococcal disease
Gram -ve septicaemia
Herpes Zoster
Cerebral malaria
Visceral leishmaniasis
123
Q

What serology is consistent with acute EBV infection?

A

EBV viral capsid antigen IgM +ve
EBV viral caspid antigen IgG +ve
EBV nuclear antigen IgG -ve

IgM and IgG viral capsid antigens usually present at onset of illness due to long incubation period

IgM wanes 3 months later so good marker of acute infection
IgG persist for life

In the setting of acute severe illness there with immune reactivation there may be serologic EBV reactivation with detectable IgM VCA without clinical EBV infection

Past infection

  • Viral caspid IgG +ve
  • EBV nuclear antigen +ve
124
Q

When is EBV nuclear antigen IgG expressed?

A

When the virus becomes latent
appears 6-12 weeks after onset of symptoms and persist throughout life
Presence in early illness excludes acute infection

125
Q

Asymptomatic bacteriuria. Tx indicated in?

A

Pregnancy
- 30-40% will develop symptomatic UTI and greater risk of pyelonephritis

Prior to urological intervention that will cause mucosal bleeding

126
Q

Which abx is least likely to cause C. diff?

A

Tigecylcine - tetracycline derivative

May be useful in Tx of C. diff

127
Q

How do PI affect:
Buprenorphine
Oxycodone
Methadone

A

Buprenorphine
- no effect

Oxycodone
- reduce dose

Methadone
- increase dose

128
Q

Which infections require public health notification?

A

Rubella - droplet and contact precaution

Influenza - droplet and contact precaution

Japanese encephalitis (JE) infection - no precautions

Measles - respiratory isolation (-ve pressure room)

Dengue - avoid mosq expossre

129
Q

Which pulmonary infections are common in HIV infected patients?

A

Bacterial pneumonia 60%
- strep pneumonia most common, then H. influenza, then S. aureus.

PJP 20%

Mycobacteria 18%

  • MTb 80%
  • MAC, mycobacterium kansasii 20%

Virus 5%

  • CMV
  • Influenza
  • Parainfluenza
  • RSV

Fungus 2%
- crypto
Aspergillus
Endemic fungal infections

Parasite 0.5%

  • toxoplasma gondii
  • strogyloides stercoralis
130
Q

Empirical Tx of meningitis?

A

If unknown organism

  • Dexamethasone 10 mg IV stat then 6hrly +
  • Ceftriaxone 4 g IV daily or 2 g BD or Cefotaxime 2 g 6 hrly

Add vancomycin if:

  • diploccoci are seen or - pneumococal antigen assay in CSF is +ve or
  • if the pt has known or supected otitis media or
  • sinusitis or
  • has been recently treated with a beta lactam
131
Q

Meningitis Tx in a pt with immediate hypersensitivity to penicillin or cephalosporins?

A

Vancomycin and ciproflox or moxiflox

132
Q

BCG vaccination will result in a false negative result. T/F

A

False, unlikely cause a false negative result

133
Q

Which antibiotic has the highest risk of SJS?

A

Sulphonamides RR 172

Bactrim RR 160

134
Q

Which HIV therapy subclass causes lipodystrophy?

A

Zidovudine (NRTI)

PI e.g ritonavir, atazanavir, lopinavir, darunavir

135
Q

Hospital acquired pneumonia:
Def
Common cause
Tx

A

> 48 hours

Causes:
Aerobic gram -ve bacilli.
(eg, Escherichia coli, Klebsiella pneumoniae, Enterobacter spp, Pseudomonas aeruginosa, Acinetobacter spp)

Others:
Gram +ve cocci (eg, Staphylococcus aureus, including methicillin-resistant S. aureus [MRSA], Streptococcus spp)

Tx:
Low risk of MDR vs. High risk of MDR

Low risk (low risk ward, ICU 5 d)

  • Tazocin
  • add Vanc if sever sepsis and ?MRSA
  • add Gent if severe sepsis and ?Pseudomonas
136
Q

Ventilator-associated pneumonia (VAP).

Def

A

HAP that develops more than 48 to 72 hours after endotracheal intubation.

137
Q

definition of multidrug resistance in gram-negative bacilli which are important cause of HAP, VAP.

A

resistance to at least two, three, four, or eight of the antibiotics typically used to treat infections with these organisms
- all beta -lactam and quinolone antibiotics

138
Q

Extensively drug-resistant (XDR) gram-negative bacilli?

A

Extensively drug-resistant (XDR) gram-negative bacilli are defined by resistance to all commonly used systemic antibiotics except colistin, tigecycline, and aminoglycosides.

139
Q

Definition of Panresistance gram-negative organisms?

A

Panresistance refers to those gram-negative organisms with diminished susceptibility to all of the antibiotics recommended for the empiric treatment of VAP, including cefepime, ceftazidime, imipenem, meropenem, piperacillin-tazobactam, ciprofloxacin, and levofloxacin.

140
Q

HIV AE

A

Refer to Ness notes

141
Q

Hep B prophylaxis.

A

Refer to evernote

142
Q

Bacteria and their MO resistance. refer to evernote.

A

evernote

143
Q
Enterococcus faecalis IE. 
Tx
Tx if resistance to gent
Tx if resistant to pen
Tx is resistance to vanc, gent and penicillin
A

Tx
- Benpen and gent

Tx if resistance to gent
- Ceftriaxone and gent

Tx if resistant to pen
- Vanc and gent

Tx is resistance to vanc, gent and penicillin
- Daptomycin or Linezolid

144
Q

MAC.
2 major clinical presentations
Dx criteria
Tx

A

Most common cause of pulmonary disease worldwide.

2 major Clinical presentations:

  • underlying lung disease, primarily white, middle aged or elderly (EtOH, COPD, CF, bronchiectasis)
  • Non smoking females > 50y with interstitial patterns on CXR

Diagnostic criteria:
Clinical (both required)
1. pul symptoms, nodular or cavitary opacities on CXR, HRCT showing bronchiectasis with multiple nodules AND
2. Appropriate exclusion of other diagnosis

Micro

  • +ve culture from 2 induced sputum samples OR
  • +ve cultures from at least one bronchial lavage OR
  • Transbronchial or other lung Bx with granulomas or AFB and +ve culture for NTM OR Bx showing granulomas or AFB and >= 1 sputum or bronchial washings that are culture +ve for NTM.
145
Q
Nocardia (an actinomycetes):
Gram +ve rods
Transmission
Presentation
Dx
Tx
A
Transmission
- inhalation, inoculation or ingestion
Presentation
- Lungs - single or multiple noduels
- CNS - parenchymal abcess
- Skin - cutaneous lesions, lymphocutaneous

Dx

  • tissue biopsy
  • aspiration
  • pcr most accurate

Tx
- Bactrim + Imipenem or mero or amikacin PLUS 12 months of prophylaxis

146
Q

Klebsiella pneumonia in UTI resistant to amp, ceft and mero. Tx?

A

Colisitin

147
Q

What infections do Klebsiella cause?

Resistance due to?

A

common cause of nosocomial pul infections in ventilated and unventilated patients.

Resistance due to betalatamases and New dehli metallo-beta-lactamse -1 which reduces efficiency of carbapenem and betalactamase inhibitors.

148
Q
Rubella:
Presentation
Spread
Ix
Tx
A

Presentation

  • Rash, appears on face and spreads caudally, last 3-4 days. Viral load disappears concurrently with rash.
  • fever
  • lymphadenopathy

Spread
- inhalation

Ix
- ELISA

Tx
- Supportive

149
Q

Mumps:
Presentation
Ix

A

Presentation

  • non specific prodrome of low grad fever, malaise and anorexia
  • then within 48 hrs development of parotitis

Ix:
serum amylase for parotitis
lymphoctosis and leukopenia
No other investigations required

Tx:
Supportive
If meningitis, admission for IVF

150
Q

Measles:
presentation
investigations
complication

A

Presentation

  • prodrome of fever, malaise, anorexia
  • conjunctivitis, cough, coryza
  • exanthema -> Koplik’s spots
investigations
- 3 samples required
- serum sample
swab of throat or nasopharynx
urine sample

complication

  • ADEM - acute disseminated encephalomyelitis. An postinfectious AI response
  • SSPE - sub sclerosing pan encephalitis. Occurs 7-10 years after infection
151
Q

Parvovirus B19:
Spread
Contagious period

A

Close contact
Droplet precautions advised when infective

Contagious period is during viral replication, 5-10 days after exposure.
No loner infective when rash appears.

152
Q

Clinical clues for spirochete infection?

A

Exposure to ticks, antecedent rash, knee joint involvement

153
Q

Familial Med Fever ( A periodic fever syndrome):
Pathogenesis
Presentation
Dx

A

AR
Patho:
- inflammasome mediated
- deficiency C5a/IL8 implicated

Dx:
Initial attack occurs before 10-20 yo
Charcterised by sporadic, unpredictable attacks of fever and serosal inflammation.
>= 1 major (typical attacks with peritonitis, pleuritis, monoarthritis)
>= 2 minor (incomplete attacks of above)
1 minor +5 supportive criteria (FHx, spontaneous remission, age of onset, ethnic origin etc)
1 minor plus >= 4 of the first five supportive criteria

Genetic testing used to support Dx

Tx:
Colchicine to relieve attacks.
Recurrence when attacks stopped.

154
Q
Gastroeneteritis:
Bugs causing symptoms for the following:
1-6 h
12-48h
2-3 d
>7 d
A

1-6 h
- S. aureus, B. cereus

12-48h
- Sal, E. coli, vibrio

2-3 d
- Camp, Cholera, Shigella

3-4 d

  • EHEC
  • supportive care

> 7 d

  • giardia, crypto
  • ameobiasis
155
Q

Which bacteria are nitrite negative?

A

Enterobacter
Pseudomonas
Saprophyticus