Infectious Diseases & Antibiotics Flashcards Preview

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Flashcards in Infectious Diseases & Antibiotics Deck (140)
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1
Q

Which causes of gastroenteritis are relate to uncooked poultry?

A

Salmonella (non-typhoid)

Campylobacter

2
Q

What is the most common bacterial cause of gastroenteritis?

A

Campylobacter

3
Q

What is the most common infective cause of bloody diarrhoea without fever?

A

E. coli

4
Q

What is the main complication of E. coli? What does it consist of?

A

Haemolytic uraemic syndrome - triad of

Haemolytic anaemia

Acute kidney injury

Thrombocytopenia (low platelets)

5
Q

What is the name of the toxin produced by E. coli?

A

Shiga toxin

6
Q

How does typhoid fever present?

A

Systemic upset – headache fever Arthralgia

Relative bradycardia (pulse is lower than expected for temperature)

Abdominal pain and distension

Constipation or diarrhoea (pea soup diarrhoea)

Rose spots (more common in paratyphoid)

7
Q

How is typhoid fever treated?

A

Ciprofloxacin

8
Q

How is Shigella transmitted?

A

Faeces contaminated water/food

9
Q

How does shigella present?

A

Bloody diarrhoea
Abdominal cramps

Fever

Vomiting

Can cause haemolytic uraemic syndrome - AKI, haemolytic anaemia, low platelets

10
Q

How is shigella infection treated?

A

Management is mostly supportive

If severe azithromycin/ciprofloxacin can be used

11
Q

How does dengue fever present?

A

Retro-orbital headache
Facial flushing
Maculopapular rash

Fever
Myalgia
Arthralgia
Pleuritic pain
Lymphadenopathy
12
Q

How is dengue fever treated?

A

Supportive treatment with fluids and potentially blood transfusions

13
Q

What is giardiasis?

A

A parasitic infection caused by the protozoa giardia lamblia

14
Q

How is Giardiasis transmitted?

A

Faeco-oral

15
Q

How does Giardiasis infection present?

A

Long-lasting diarrhoea with associated weight loss due to malabsorption

Steatorrhoea

Associated with lactose intolerance - this may continue beyond treatment

Abdominal pain and excess flatulence

Vomiting and fever are uncommon

16
Q

How is Giardiasis treated?

A

Metronidazole

Note: After treatment there can be transient lactose intolerance

17
Q

What antibiotic is used for rheumatic fever?

A

Stat dose IV Benzylpenicillin

Oral Penicillin V

18
Q

What antibiotics are used for the initial management of IE (no culture)?

A

Native valve -> Amoxicillin

Prosthetic valve -> Vancomycin + Rifampicin + Gentamicin

19
Q

What antibiotics are used for IE which has been confirmed to be caused by a staph infection?

A

Native valve -> Flucloxacillin

Prosthetic valve -> Flucloxacillin + Rifampicin + Gentamicin

20
Q

What organism causes cellulitis and which antibiotics are used?

A

Most common organism = staph aureus

1st line = Flucloxacillin (Clarithromycin/Erythromycin if pen allergic)

If severe = Co-amoxiclav or a cephalosporin

21
Q

What organism causes Erysipelas and what antibiotic is used?

A

Usually caused by strep pyogenes

First line is Fluclox

22
Q

What is the first and second line treatment for impetigo? What about if it’s widespread?

A
  1. Hydrogen peroxide cream
  2. Topical fusidic acid
  3. Oral flucloxacillin
23
Q

What organism most commonly causes acute otitis media and wha is the antibiotic of choice?

A

Organism = strep pneumoniae/haem influenzae

Abx = Amoxicillin (or Clarithromycin)

24
Q

What are indications for Abx in acute otitis media?

A

Symptoms lasting more than 4 days

Systemically unwell

Immunocompromised

Under 2 years with bilateral otitis media

Perforation/discharge

25
Q

What is the most common organism that causes otitis externa and what is the antibiotic of choice?

A

Organism = Pseudomonas and staph aureus

Abx = topical Neomycin + Dexamethasone

If tympanic membrane is perforated = Ciprofloxacin + Dexamethasone

26
Q

How is malignant otitis external managed?

A

IV Ciprofloxacin

27
Q

What is the most common organism that causes tonsillitis and what is the antibiotic of choice?

A

Organism = strep pyogenes

Abx = Penicillin V (or Clarithromycin)

28
Q

What is the triple eradication therapy for H.pylori?

A

PPI + Amoxicillin + Clarithromycin/Metronidazole

If pen allergic - PPI + Clarithromycin + Metronidazole

29
Q

What antibiotic is used for diverticulitis?

A

Oral co-amoxiclav

If no improvement -> IV Ceftriaxone + metronidazole

30
Q

What is the most common organism that causes peritonitis and what is the antibiotic of choice?

A

Organism = E.coli

Abx = IV Cefotaxime / Tazocin

31
Q

What prophylaxis do patients who have had an episode of spontaneous bacterial peritonitis require?

A

Oral Ciprofloxacin

32
Q

What is the first line management for C.diff? What if it is life-threatening? What indicates a life-threatening infection?

A

First line = oral Vancomycin

Life-threatening = oral Vancomycin + IV Metronidazole

Life-threatening = hypotensive

33
Q

What antibiotics are used for neutropenic sepsis?

A

IV Tazocin

34
Q

What is used to treat encephalitis?

A

IV Aciclovir

35
Q

What is the most common cause of meningitis and how is it treated?

A

Organism = Neisseria meningitidis

<3 months = IV Cefotaxime + Amoxicillin
3m-50 years = IV Cefotaxime
>50 years = IV Cefotaxime + Amoxicillin

Ceftriaxone is an alternative to Cefotaxime

Not Cefuroxime

36
Q

What prophylaxis are close contacts of someone with diagnosed meningitis given?

A

Oral ciprofloxacin or rifampicin

37
Q

What is the antibiotic used for intrapartum prophylaxis of Group B strep?

A

IV Benzylpenicillin

38
Q

What is the causative organism of UTI and what is the antibiotic of choice?

A

Nitrofurantoin/Trimethoprim

1st and 2nd trimester = Avoid trimethoprim

At term = Avoid nitrofurantoin

39
Q

What is the causative organism and treatment for osteomyelitis?

A

Organism = staph aureus

Abx = 6 weeks fluclox IV (or clindamycin)

40
Q

What is the causative organism and antibiotic of choice for septic arthritis?

A

Organism = staph aureus

Abx = flucloxacillin + rifampicin

41
Q

What is the antibiotic of choice for BV?

A

Metronidazole

42
Q

What is the antibiotic of choice for Trichamonas?

A

Metronidazole

43
Q

What is the antibiotic of choice for Chlamydia?

A

Doxycycline

In pregnancy = Azithromycin/erythromycin

44
Q

What is the antibiotic of choice for Gonorrhoea?

A

IM Ceftriaxone

45
Q

What is the antibiotic of choice for Syphilis?

A

IM Benzathine Benzylpenicillin

46
Q

What antibiotic is used for COPD exacerbations?

A

Amoxicillin / Doxycycline / Clarithromycin

47
Q

What is the most common organism which causes COPD exacerbations?

A

Haemophilus influenzae

48
Q

What antibiotic can be used for acute bronchitis and when is it used?

A

Doxycycline

If raised CRP >100 / systemically unwell / co-morbidities (asthma/COPD)

49
Q

What antibiotics are used for community-acquired pneumonia?

A

CURB-65 score

0/1 -> Amoxicillin
2 -> Amoxicillin + Clarithromycin (admission)
3-5 -> IV Co-Amoxiclav + Clarithromycin (admission)

50
Q

What antibiotic is used for hospital-acquired pneumonia?

A

Co-amoxiclav

If severe -> Tazocin

51
Q

Which antibiotics are used for aspiration pneumonia?

A

IV Cephalosporin + Metronidazole

52
Q

Which antibiotics are used for TB?

A

Isoniazid 6m
Rifampicin 6m
Pyrazinamide 2m
Ethambutol 2m

53
Q

What antibiotic is first line for campylobacter? When should it be given?

A

Clarithromycin, if immunocompromied

54
Q

What are complications of camylobacter infection?

A

Guillan barre syndrome

Reactive arthritis

55
Q

Which type of pneumonia is predisposed by a preceding influenza infection?

A

Staph aureus

56
Q

Which type of pneumonia is classically in alcoholics?

A

Klebsiella

57
Q

Which pneumonia classically causes a bilateral consolidation and potentially haemolytic anaemia/erythema multiforme (target lesions?

A

Mycoplasma pneumoniae

58
Q

Which bacteria is most commonly associated with eating undercooked rice?

A

Bacillus cereus

59
Q

Pneumonia symptoms + pain in extremities?

A

Mycoplasma pneumoniae

Due to autoimmune haemolytic anaemia

60
Q

What is the most common type of Malaria?

A

Plasmodium Falciparum

61
Q

How does Malaria typically present?

A
Returning traveller
High fever
Malaise
Myalgia
Headache
Jaundice
62
Q

What are complications of malaria?

A

Hypoglycaemia

Cerebral malaria (seizures)

ARDS

Acute renal failure

DIC

63
Q

How is malaria diagnosed?

A

Schizonts on blood film

64
Q

How can malaria be excluded?

A

Need at least 3 blood samples on 3 different days

65
Q

What are signs of malaria?

A

Haemolytic anaemia

Hepatosplenomegaly

Jaundice

Low platelets

66
Q

What is the most common non-falciparum malaria?

A

Plasmodium vivax

67
Q

Malaria with cyclical fever every 48 hours?

A

Plasmodium vivax / plasmodium ovale

68
Q

How is malaria treated?

A

Chloroquine

Patients with ovale/vivax need Primaquien following acute treatment

69
Q

How does amoebiasis present?

A

Can be asymptomatic, present with amoebic dysentry or liver abscessess

Amoebic dysentry = Profuse bloody diarrhoea

If amoebiasis liver abscess - fever, RUQ pain

70
Q

How does Cholera present?

A

Traveller’s diarrhoea

Profusely watery diarrhoea

Abdominal cramps

Patient will be severely dehydrated

71
Q

How does leprosy present? How is it treated?

A

Patches of hypopigmented skin with sensory loss over the patches

Triple therapy - Rifampicin/Dapsone/Clofazimine

72
Q

What is leptospirosis? Who does it occur in and how does it present?

A

Infection which is spread by infected rat urine

In sewage workers/farmers/vets

Fever, flu-like symptoms

Red eyes

AKI

Hepatitis

73
Q

What is the causative organism of Lyme disease?

A

Borrelia Burgdorferi

74
Q

How does Lyme disease present?

A

Early features = Erythema migrans (bulls-eye rash)
Usually 1-4 weeks after bite
PAINLESS
May be systemic features - headache, lethargy, fever

Late features = Heart block/pericarditis/facial nerve palsy/meningitis

75
Q

How is Lyme disease diagnosed?

A

Usually can be diagnosed clinically with erythema migrans

76
Q

How is Lyme disease treated?

A

Doxycycline

Amoxicillin if Doxy is CI

77
Q

What is the usual carrier of Toxoplasmosis?

A

Cat

78
Q

How does Toxoplasmosis present?

A

Resembles mononucleosis

Fever

Malaise

Lymphadenopathy

79
Q

How can Toxoplasmosis affect patients with HIV?

A

Can cause CNS symptoms - headache/confusion/drowsiness

Will present on CT as ring-enhancing lesions

80
Q

How is Toxoplasmosis treated?

A

Pyrimethamine + Sulphadiazine

81
Q

What are the two causes of pneumonia + deranged LFTs?

A

Legionella

Mycoplasma

82
Q

How does legionella pneumonia present?

A

Dry cough

Deranged LFTs

Low lymphocytes

Low sodium

83
Q

How is legionella diagnosed?

A

Urinary antigen

84
Q

How is mycoplasma diagnosed?

A

serology

85
Q

How does mycoplasma pneumonia present?

A

Flu like symptoms

Dry cough

Bilateral consolidation

Cold autoimmune haemolytic anaemia

Erythema multiforme

86
Q

How is Legionalla + Mycoplasma treated?

A

Macrolide

87
Q

What is the first line treatment for MRSA?

A

Vancomycin

88
Q

What pathogen causes TB?

A

Mycobacterium tuberculosis

89
Q

How is primary TB seen on a CXR?

A

Ghon focus (caseating granuloma)

90
Q

How is TB meningitis seen on lumbar puncture?

A

Raised protein

Low glucose

Raised lymphocytes

91
Q

How is latent TB diagnosed?

A

Mantoux test or Interferon-gamma blood test

92
Q

How is active TB diagnosed?

A

Sputum culture = gold standard but this can take a long time

Ziehl-Neelsen stain is often used

93
Q

What are options for malaria prophylaxis?

A

Doxycycline

Mefloquine

Proguanil + Atovaquone

94
Q

Which types of hepatitis are spread faeco-orally?

A

Hepatitis A

Hepatitis E

95
Q

Which types of hepatitis are spread bloodbourne?

A

Hepatitis B

Hepatitis C

Hepatitis D

96
Q

Hepatitis B antibodies: HbsAb(Anti-HbS) positive

A

Immunised

97
Q

Hepatitis B antibodies: HBcAb and HBsAb

A

Previous infection and now resolved

98
Q

Hepatitis B antibodies: HBsAg and HBcAb

A

Chronic infection

99
Q

How to manage a neonate whose mother has Hepatitis B?

A

HBIG within 24 hours of birth

Full course of vaccinations

100
Q

How is HIV monitored?

A

CD4 T-cell count

HIV viral load

101
Q

What is the progression of HIV?

A

Acute primary infection (seroconversion) = fever, malaise, lymphadenopathy
Usually 2-4 weeks post exposure

Asymptomatic phase - progressive loss of CD4 T cells

Early symptomatic phase

AIDS

102
Q

What are AIDS defining illnesses?

A
Kaposi's sarcoma
Pneumocystis pneumonia
CMV infection
Oesophageal/bronchial candidiasis
Lymphoma
TB
103
Q

How is HIV diagnosed?

A

p24 antigen
Antibody (takes longer to become positive)
PCR

104
Q

How is HIV treated?

A

Triple antiretroviral therapy - NRTI/NNRTI/Protease inhibitor

105
Q

What is Kaposi’s sarcoma?

A

AIDS defining illness
Caused by HHV8
Papules/macules/nodules across body

106
Q

How is PCP treated?

A

Co-trixomazole

107
Q

Who needs PCP prophylaxis?

A

HIV with CD4 count <200

108
Q

What antibiotic should be given in the case of an animal or human bite?

A

Oral co-amoxiclav

109
Q

What is the most common cause of viral meningitis?

A

Enteroviruses e.g. Coxsackie

110
Q

What is seen on lumbar puncture in viral meningitis?

A

Lymphocyte predominant

Normal glucose

Raised protein ???

111
Q

What is the most common cause of necrotising fasciitis?

A

Strep pyrogenes

112
Q

How is necrotising fasciitis treated?

A

IV Abx + urgent surgical debridement

113
Q

What is seen on CXR in PCP?

A

Interstitial pulmonary infiltrates

114
Q

What might make you suspect meningococcal meningitis?

A

Non-blanching rash

115
Q

How is meningococcal meningitis treated in hospital?

A

Prior to admission = IM benzylpenciilln

In hospital = IV Benzylpenicillin or IV Ceftriaxone

If sensitivity to penicillin and cephalosporins = Chloramphenicol

116
Q

How is bacterial meningitis (aetiology unknown) treated in hospital?

A

3yrs-50 years = Cefotaxime/Ceftriaxone

> 50 years = Ceftriaxone/Cefotaxime + Amoxicillin

117
Q

How long is HIV Post-exposure prophylaxis?

A

4 weeks

118
Q

What are side effects of tetracyclines?

A
Discolouration of teeth
Photosensitivity
Black hairy tongue
Angioedema
IIH
119
Q

Which types of gastroenteritis present within hours of eating the contaminated food?

A

Staph aureus

Bacillus cereus

120
Q

What is the incubation period of Salmonella?

A

24-48 hrs

121
Q

What is the incubation period of E.coli?

A

24-48 hours

122
Q

Which causes of gastroenteritis have an incubation period of more than 7 days?

A

Giardiasis

Amoebiasis

123
Q

Which macrolides are safe in pregnancy?

A

Erythromycin or Azithromycin

NOT Clarithromycin

124
Q

Which malignancies are associated with EBV?

A

Burkitt’s Lymphoma
Hodgkin’s Lymphoma
Nasopharyngeal carcinoma

125
Q

What is the most severe complication of Chagas disease?

A

Cardiomyopathy

126
Q

What is the most common cause of pneumonia in patients who have CF?

A

Pseudomonas

127
Q

What should be tested for in everyone diagnosed with TB?

A

HIV

128
Q

What can cause a false negative Mantoux test in a patient with TB?

A
Sarcoidosis
Immunosuppression - AIDS, steroids
Lymphoma
Fever
Hypoalbuminaemia
Anaemia
129
Q

What can cause a false positive Mantoux test in a patient who does not have TB?

A

BCG vaccination

130
Q

HIV + Neuro symptoms – How can you tell the diagnosis from MRI head?

A

Multiple ring enhancing lesions = Toxoplasmosis

Single homogenous enhanced lesion = Lymphoma

131
Q

Chancroid vs. Syphilis Chancre vs Lymphogranuloma vereneum?

A

Painless ulcer and painless lymphadenopathy = Syphilis (Chancre)

Painless ulcer and painful lymphadenopathy = LGV

Painful ulcer and painful lymphadenopathy = Chancroid

132
Q

Which bacteria stains with India ink?

A

Cryptococcus

133
Q

How does cryptococcosis present on LP?

A

High opening pressure

India ink staining positive

134
Q

Which types of hepatitis have an increased risk of developing hepatocellular carcinoma?

A
Hepatitis C (Most common)
Chronic hepatitis B
135
Q

How is hep A managed?

A

Self limiting

136
Q

Which drug should be given alongside isoniazid?

A

Pyridoxine (Vitamin B6)

137
Q

What is used to treat cytomegalovirus retinitis?

A

IV Ganciclovir

138
Q

Which antibiotic used for whooping cough?

A

Clarithromycin

139
Q

What is schistosomiasis and how does it present?

A

Parasitic flatworm infection
Enters from water - from freshwater swimming

Initially presents with a swimmer’s itch

Can then lead to hepatosplenomegaly, RUQ pain

Chronic = haematuria + dysuria

140
Q

How is schistosomiasis treated?

A

Praziquantel