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Microbiology Flashcards

1
Q

Give some examples of penicillins.

A

Flucloxacillin
amoxillicin
benzylpenicillin
penicillin V

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2
Q

Describe the mechanism of action of penicillins.

A
  • attaches to penicillin-binding proteins on forming bacterial cell walls
  • this inhibits transpeptidase enzyme which cross-links bacterial cell wall
  • failure to cross-link induce cell autolysis
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3
Q

When should flucloxacillin be used?

A
  • soft tissue infection
  • staphylococcal endocarditis
  • otitis externa
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4
Q

Which drug should be used in non-severe CAP?

A

amoxicillin

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5
Q

List common side effects of penicillins.

A
  • diarrhoea
  • vomiting
  • liver function impairment
  • hypersensitivity reactions (anaphylaxis)
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6
Q

Clavulonic acid is often given alongside which drug? And why?

A

amoxicillin, as it is beta-lactamase susceptible (mechanism of resistance) - forming co-amoxiclav

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7
Q

Gentamicin is an example of which type of antibiotics?

A

aminoglycosides

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8
Q

How does gentamicin work?

A
  • binds to 30s ribosomal subunit, inhibiting protein synthesis, inducing a prolonged post-antibiotic bacteriostatic effect
  • bactericidal action on cell wall results in rapid killing early in dosing interval and is prominent at high doses
  • provides a synergistic effect when used alongside other antibiotics (e.g. flucloxacllin or vancomycin in gram+ve infections)
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9
Q

When should gentamicin be used clinically?

A
  • severe gram -ve infections e.g. biliary tract infection, pyelonephitis, HAP
  • some severe gram +ve infections e.g. soft tissue infection, endocarditis
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10
Q

Nephrotoxicity and ototoxicity are caused by high-dose prolonged exposure to which antibiotic?

A

Gentamicin

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11
Q

Describe the importance of careful dosing in gentamicin prescribing.

A
  • give high initial dose to take advantage of rapid killing
  • leave long dosing interval to minimise toxicity
  • measure trough level to ensure it is not accumulating
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12
Q

How many days should you limit gentamicin use to?

A

3 days - minimise risk of SE

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13
Q

Which antibiotics work by interfering with bacterial DNA replication and repair? Give an example of one.

A

Quinolones

e.g. ciprofloxacin

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14
Q

Describe the spectrum of use and action of ciprofloxacin.

A

Broad spectrum bactericidal - both gram+ve and gram-ve cover

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15
Q

List the indications of quinolone antibiotic use.

A
  • gram-ve bacterial infection
  • respiratory tract infection
  • upper urinary tract infection
  • peritoneal infection
  • gonorrhoea
  • prostatitis
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16
Q

Give some side effects of ciprofloxacin.

A
  • GI toxicity
  • QT wave prolongation
  • C. diff. infection (antibiotic associated diarrhoea)
  • tendonitis (rare)
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17
Q

Ceftriaxone and cephalexin are examples of which type of antibiotic?

A

Cephalosporin

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18
Q

What is the mechanism of action of cephalosporins?

A
  • attaches to penicillin-binding-proteins on forming bacterial cell walls
  • this inhibits transpeptidase enzyme which cross-links bacterial cell wall
  • failure to cross-link induces bacterial cell autolysis
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19
Q

Are penicillins or cephalosporins more susceptible to beta-lactamases?

A

penicillins

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20
Q

Describe the coverage of cephalosporins.

A

both gram+ve and gram-ve

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21
Q

When should cephalosporins be used?

A

serious infection - septicaemia/pneumonia/meningitis

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22
Q

What are the common side effects of cephalosporins?

A
  • hypersensitivity reactions
  • antibiotic-associated C. diff. diarrhoea
  • liver function impairment
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23
Q

How is cephalosporins excreted?

A

kidneys

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24
Q

Cephalosporins have a long half-life, what impact does this have on their use?

A

needs to be given once daily

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25
Q

Which antibiotic group is bactericial, inhibiting cell-wall synthesis in gram+ve bacteria?

A

glycopeptides e.g. vancomycin

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26
Q

Which antibiotic is most commonly utilised in MRSA infection?

A

vancomycin

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27
Q

What are the clinical uses of vancomycin?

A
  • severe gram+ve infections
  • MRSA
  • severe C. diff. infection
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28
Q

Vancomycin has many side effects. What are they?

A
  • fever
  • rash
  • local phlebitis at site of injection
  • nephrotoxicity
  • ototoxicity
  • blood disorders - neutropaenia
  • anaphylactoid reaction if infusion rate too fast
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29
Q

How is vancomycin administered?

A

either given as a continuous IV infusion or as a pulsed infusion regimen

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30
Q

Why is therapeutic drug monitoring undertaken with vancomycin?

A

it has a narrow therapeutic range

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31
Q

Give two examples of macrolides.

A

clarithromycin

erythromycin

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32
Q

Describe the mechanism of action of macrolides.

A
  • bacteriostatic and bacteriocidal
  • binds to 50s ribosomal subunit
  • inhibits bacterial protein synthesis
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33
Q

When should macrolides be used?

A
  • atypical organisms causing pneumonia/severe CAP
  • severe campylobacter infection
  • mild/moderate skin and soft tissue infection
  • otitis media
  • Lyme disease
  • H. pylori eradication therapy
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34
Q

Which antibiotics use the hepatic enzyme cytP450 pathway? And so what drugs do they interact with?

A

macrolides - and so interact with all drugs using this pathway e.g. simvastatin, atorvastatin, warfarin

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35
Q

What important patient information needs to be given when administering macrolides?

A
  • risk of diarrhoea
  • senses of smell and taste may be disturbed
  • tooth and tongue discolouration may occur
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36
Q

Describe the mechanism of action of trimethoprim.

A
  • inhibits folate metabolism pathway and leads to impaired nucleotide synthesis
  • therefore interferes with bacterial DNA replication
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37
Q

What are the indications of trimethoprim?

A
  • first line antibiotic in uncomplicated UTI
  • acute/chronic bronchitis
  • pneumocystis pneumonia
  • gram -ve, gram +ve and some MRSA cover
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38
Q

List the side effects of trimethoprim.

A
  • elevated serum creatinine
  • hyperkalaemia - especially in those with impaired renal function
  • depressed haematopoiesis
  • rash and GI disturbance
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39
Q

Note some important PK and PD of trimethoprim.

A
  • penetrates well into the prostate - suitable for men with uncomplicated UTI
  • avoid in first trimester of pregnancy
  • resistant organisms
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40
Q

What are the 4C’s that cause C. diff infection?

A

clindomycin, co-amoxiclav, cephalosporin, ciprofloxacin

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41
Q

Briefly describe the pathophysiology of C. diff infection.

A
  • infection causes pseudomembranous colitis leading to severe diarrhoea, abdominal pain, fever and nausea
  • toxins induce inflammation and cell death
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42
Q

List some anaerobes.

A
  • clostridium

- bacteroids

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43
Q

List some gram+ve coccus bacteria.

A
  • staphylococcus
  • streptococcus
  • enterococcus
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44
Q

List some gram-ve rod bacteria.

A
  • pseudomonas
  • haemophilus
  • E. coli
  • other coliforms
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45
Q

List the 6 investigations that must be carried out within 1hr of sepsis recognition.

A
  1. Perform blood cultures
  2. Antibiotic administration
  3. Oxygen to achieve target saturation
  4. Measure lactate and Hb
  5. IV fluids
  6. Monitor urinary output hourly
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46
Q

IV amoxicillin should be administered in?

A

Group A strep infections
pneumococcus
meningococcus

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47
Q

List some gram+ve rod bacteria.

A

Clostridia
Bacillus
Listeria

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48
Q

Meningococcus is an example of what type of bacteria?

A

Gram-ve coccus

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49
Q

What is the SIRS criteria?

A
  • Temperature: <36 °C or >38 °C
  • Heart rate: >90/min
  • Respiratory rate >20/min or PaCO2 <32 mmHg (4.3 kPa)
  • WBC <4x10^9/L or >12x10^9/L
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50
Q

What is the standard short course therapy for tuberculosis?

A

Isoniazid & rifampicin for full 6 months

Pyrazinamide & ethambutol for first 2 months

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51
Q

Which antibiotics are not safe to use during pregnancy? And why?

A

Tetracyclines: bone abnormalities
Trimethoprim: neural tube defects
Gentamicin: ototoxicity
Quinolone: bone abnormalities

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52
Q

Horizontal gene transfer has more importance in antimicrobial resistance. What are the three mechanisms of horizontal transfer?

A

Conjugation
Transduction
Transformation

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53
Q

Describe the four main mechanisms of antibiotic resistance.

A
  1. Production of enzyme that inactive or modify antimicrobials eg beta lactamases
  2. Target modification
  3. Decreasing cell permeability
  4. Bacteria export drug from inside cell, drug exchanges for protons
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54
Q

What does MRSA stand for?

A

Methicillin (flucloxicillin) resistant staphylococcus aureus

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55
Q

Which inherited condition is linked to a defect in the gene coding for NADPH oxidase? What is the consequence of this disease?

A

Chronic granulomatous disease

Recurrent bacterial and fungal infections - abscesses, lung, lymph nodes, skin

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56
Q

Describe the pathophysiology of neutropenia in cancer patients.

A

Cytotoxic chemotherapy and therapeutic irradiation
Decreased proliferation of haemopoietic progenitor cells
Neutropenia

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57
Q

What is the clinical definition of neutropenia?

A

<0.5x10^9/L or <1.0x10^9/L and falling

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58
Q

What antibiotics should be prescribed in the immediate management of neutropenic shock?

A

Pipercillin & tazobactam

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59
Q

What pathogens commonly cause cellulitis?

A

Beta haemolytic strep group A

S. Aureus

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60
Q

Which antibiotic should be prescribed initially in cellulitis?

A

Flucloxicillin

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61
Q

Describe the management plan for necrotising fasciitis.

A

Urgent surgical debridement
Clindomycin
Immunoglobulin

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62
Q

How would you manage a presentation of COPD exacerbation with green sputum?

A

Hospitalisation
Administer doxycycline or amoxicillin
<5 days

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63
Q

What are the clinical features of malaria?

A

fever, malaise, headache, myalgia, diarrhoea, anaemia, jaundice, renal impairment

64
Q

How is malaria treated?

A

Riamet, quinine, doxycycline

65
Q

What are the clinical features of dengue fever?

A

‘breakbone fever’ - headache, fever, retro-orbital pain, myalgia, rash, cough, sore throat, nausea, diarrhoea

66
Q

What is seen in laboratory findings in dengue fever?

A

leucopenia, thrombocytopenia, transaminitis

67
Q

How is dengue fever managed?

A

symptomatic

68
Q

Describe the serious complication of dengue fever which is less likely to occur in travellers.

A

dengue haemorrhagic fever

increased vascular permeability, thrombocytopenia, fever, bleeding

69
Q

Which two pathogens cause enteric fever?

A

S. typhi

S. paratyphi

70
Q

Describe the clinical features of typhoid and paratyphoid.

A

GI: diarrhoea vs constipation, abdo pain, rectal bleeding, bowel perforation
neurological: headache, enteric encephalopathy
bacteraemia

71
Q

How would a diagnosis of enteric fever be made?

A

travel history
blood culture
stool culture

72
Q

How is enteric fever treated?

A

quinolones - effective but resistance an issue
cephalosporins - empirical therapy
azithromycin

73
Q

List causes of viral haemorrhagic fever.

A

Lassa, Ebola/marburg, CCHF, SAVHFs, RVF, DHF, yellow fever

74
Q

Discuss the natural history of viral haemorrhagic fever.

A

exposure - non-specific febrile illness - haemorrhagic manifestations - sepsis syndrome/shock - death

75
Q

How is viral haemorrhagic fever managed?

A

supportive
correct coagulative/anaemia
ribavirin?

76
Q

Define diarrhoea.

A

abnormal frequency and/or fluid stool - usually indicates small bowel disease and causes fluid and electrolyte loss

77
Q

What is dysentery?

A

inflammatory disorder of large bowel leading to blood and pus in faeces, pain, fever and abdo cramps

78
Q

What is haemolytic uraemic syndrome and which pathogen causes it?

A

E. coli 0157
microangiopathic haemolytic anaemia
thrombocytopenia
acute renal failure

79
Q

Which pathogen causing gastroenteritis is associated with Guillain-Barre syndrome (ascending paralysis due to demyelination)?

A

campylobacter

80
Q

Which pathogen is associated with causing cramps, vomiting and diarrhoea in reheated fried rice?

A

bacillus cereus

81
Q

The clinical features associated with Clostridium botulinum infection differ from the usual symptoms of gastroenteritis such as diarrhoea and vomiting. What are they?

A

flaccid paralysis
progressive muscle weakness
resp. failure

82
Q

What is the antibiotic treatment for Clostridium difficile?

A

moderate - metronidazole

severe - oral vancomycin

83
Q

What are the five viruses that cause gastroenteritis?

A

norovirus, rotavirus, sapovirus, adenovirus, astrovirus

84
Q

How many genogroups does norovirus have? Which genotype is the most common?

A

5 - only 3 affect humans

GII-4

85
Q

Describe the clinical features of norovirus and how it is treated.

A

N&V, diarrhoea, abdo cramps, headache, myalgia, fever, dehydration
symptomatic therapy - fluids, antispasmodics, analgesics, antipyretics

86
Q

What vaccine is available for rotavirus?

A

rotarix - protects against severe infection in first two years

87
Q

Which antibodies and Igs are important in immunity against rotavirus?

A

VP7 and VP4

secretory IgA

88
Q

Which two strands of adenovirus commonly cause gastroenteritis?

89
Q

What are the complications associated with rotavirus?

A

severe chronic diarrhoea, dehyrdation, electolyte imbalance, metabolic acidosis

90
Q

How is the qSOFA score used to detect sepsis?

A

A score of ≥2 of:

  • Confusion (<15 of Glasgow Coma Scale)
  • Respiratory rate ≥22/minute
  • Systolic blood pressure ≤100mmHg
91
Q

A patient presents with a red, hot, swollen knee joint with pain and loss of movement. He also says that he has a fever. What are the initial investigations that you would carry out?

A

blood cultures, joint aspirate, FBC, CRP, imaging

92
Q

What is osteomyelitis?

A

progressive infection of bone characterised by death of bone and the formation of sequestra

93
Q

How might osteomyelitis be spread?

A

haematogenous

contiguous - overlying infection e.g. cellulitic ulcer, trauma, surgery

94
Q

Which bacteria commonly cause septic arthritis?

A

streptococcus

MRSA/MSSA

95
Q

Name an infection which causes spinal deformity and instability, cord compression, paraplegia and disability.

A

vertebral discitis - infection of a disc space and adjacent vertebrae

96
Q

What are the risk factors associated with developing a prosthetic joint infection following primary arthroplasty?

A

RA, diabetes, poor nutritional status, obesity, concurrent UTI, steroids, malignancy

97
Q

List some risk factors associated with developing a prosthetic joint infection following revision arthroplasty.

A

prior joint surgery, prolonged operating room time, pre-op infection

98
Q

What two ways might a prosthetic joint infection spread?

A

local and haematogenous

99
Q

Which antibiotics might be used as prophylatic therapy for PJI?

A

cephalosporins (+vanc if MRSA suspected)

100
Q

What are the surgical options available in prosthetic joint infections?

A
  1. DAIR - debride, antibiotics, implant retained, if <30 days
  2. Take joint out > 30 days Girdlestone procedure
101
Q

List some of the typical and atypical pathogens that cause pneumonia.

A

typical - strep. pneumoniae, haemophilus influenzae, moraxella catharralis
atypical - mycoplasma pneumoniae, legionella pneumoniae

102
Q

What is the most common cause of community acquired pneumonia?

A

streptococcus pneumoniae

103
Q

What the clinical features and examination findings associated with typical pneumonia?

A

CF: abrupt onset cough, fever, pleuritic chest pain
Examination: dull percussion, coarse crepitus, increased vocal resonance

104
Q

Which strain of H. influenzae has been vaccinated against because it causes epiglottitis?

105
Q

Which pathogens commonly cause pneumonia in patients with a bad underlying lung disease such as COPD or CF?

A

H. influenzae

M. catharralis

106
Q

What features of a clinical history would make you suspect a legionella pneumoniae infection?

A

near public waters, AC, warmer parts of world - aerosol of water or soil infects macrophages in lungs

107
Q

Which pathogen is responsible for an atypical presentation of pneumonia which is initially flu-like with resp. symptoms developing over time?

A

legionella pneumoniae

108
Q

Which investigation is crucial in diagnosing legionella pneumoniae infection?

A

urine antigen test

109
Q

Which antibiotics are effective against atypical pneumonia infection?

A

ciprofloxacin

clarithomycin

110
Q

List the clinical features associated with the atypical mycoplasma pneumoniae.

A

non-specific flu-like, fever, cough

outwith lungs = haemolysis, GB syndrome, erythema multiforme, cardiac, arthritis

111
Q

Discuss the CURB65 clinical assessment score for diagnosing severe pneumonia.

A 
C = confusion
U = urea > 7
R = RR > 30
B = BP dia < 60 and sys < 90
65 = over 65
> 2 + multilobular consolidation on CXR and/or hypoxia on room air = severe pneumonia
112
Q

List the viral causes of the common cold and how it presents.

A

rhinovirus, coronavirus

sore throat, rhinorrhoea, nasal obstruction, sinusitis, otitis media

113
Q

What are the common viral causes of pharyngitis and how does its presentation differ from bacterial?

A

adenovirus, rhinovirus, influenza, parainfluenza, EBV
sore throat + pharyngeal inflammation = pharyngitis
+ nasal symptoms = viral

114
Q

Croup presents in childhood with a very distinctive cough. What pathogen most commonly causes this?

A

parainfluenza virus 1-4

115
Q

A child presents with a three week history of cough and week long history of wheeze and fast heart rate. Which pathogen is associated with this presentation?

A

respiratory syncytial virus - bronchiolitis

116
Q

What medications are available to treat RSV infection? List some side effects associated with these.

A
  1. Ribivirin
    - tiredness, nausea, fever, pains
    - severe: RBC breakdown, liver problems
  2. Palivizumab
    - prophylactic monoclonal antibody
    - given IM monthly - expensive
117
Q

Influenza presents with a 3-5 day history of flu-like and respiratory symptoms. What complications are associated with this virus?

A
  • common: otitis media, sinusitis, pneumonia, dehydration, exacerbation of underlying disease
  • uncommon: encephalopathy, Reye syndrome, myositis, myocarditis
118
Q

What groups are more susceptible to severe influenza infection?

A

> 65s, <6m, pregnancy, obesity, diabetes, immunosuppression, organ damage

119
Q

Which virulence factor produced by Staphylococcus aureus is associated with severe rapidly progressing necrotising infection?

A

Panton-Valentine leucocidin

120
Q

A 27 year old man with HIV has a raised red lesion on his back and a clinical diagnosis of Kaposi’s sarcoma is made. Which virus is associated with Kaposi’s sarcoma?

A

human herpes virus 8

121
Q

What are the symptoms of TB?

A

cough, fever, night sweats, SOB, weight loss, haemoptysis, pleural effusion

122
Q

Describe the progression of infection of TB.

A
  1. TB is inhaled - mycobacterium tuberculosis
  2. TB meets macrophages and secretes a substance that prevents the lysosome from fusing with the phagosome so TB remains within macrophages
  3. Haematogenous spread
  4. Reactivation of TB - after immunosuppression, HIV infection or smoking leads to cavitary TB
  5. Cavities open into bronchi, allowing spread by coughing
123
Q

Discuss the lab tests used to detect TB.

A

T spot test
tuberculin skin test - Mantoux reaction for latent TB
Zeihl Neelson stain - purple rods specific for TB
AAFB positive lab test

124
Q

Granuloma is a pathological hallmark of TB. Can you describe its appearance?

A

central caseous necrosis surrounded by epithelial cells, Langhan’s giant cells and lymphocytes

125
Q

What are the side effects associated with the drugs prescribed in TB?

A

rifampicin = reddish urine
isoniazid = liver toxicity
pyrazanimade
ethambutol = vision

126
Q

A young woman presents with history of burning on urination and vaginal discharge. You require a urine culture and there appears to be a gram -ve diplococci bacteria present. What is the diagnosis?

A

gonorrhoea

127
Q

Where should a swab be taken to carry out a NAAT test for gonorrhoea and chlamydia?

A
  • male: urine sample +/- throat swab (MSM)

- female: vulvovaginal swab

128
Q

What are the symptoms of disseminated gonorrhoea?

A

skin pustules, septic arthritis, meningitis, endocarditis

129
Q

Discuss the antibiotic treatment of gonorrhoea.

A

ceftriaxone and azithromycin

130
Q

What is a major complication of chlamydia in females?

A

tubal damage/infertility

131
Q

What antibiotics should be used following diagnosis of chlamydia?

A

doxycyline and azithromycin

132
Q

What is lymphogranuloma venereum associated with chlamydia?

A

lymphotrophic chlamydia
severe proctitis causing constipation and rectal bleeding
inguinal ‘bubos’

133
Q

What pathogen causes syphilus?

A

Treponema pallidum bacteria

134
Q

Describe the natural progression of syphilus.

A
  • 3 weeks: first lesion = chancre = firm, painless, non-itchy skin ulcer
  • 8-16 weeks: second lesion = rash = symmetrical, reddish, non-itchy on trunk
  • latent syphilus (+ve serology only)
  • 10-40 years: tertiary syphilus: gumma, CV, neurological
135
Q

What are some of the most generalised symptoms of syphilus?

A

fever, malaise, hair loss, weight loss, headache

136
Q

Describe the treatment for syphilus.

A

single IM benzathic benzylpenicillin

137
Q

Name three viral STIs.

A

genital warts
molluscum contagiosum
herpes simplex

138
Q

What vaccination is available for genital warts?

A

Gardasil - HPV 6, 11, 16, 18

139
Q

What treatment is available for genital warts?

A

physically ablative

topical agents

140
Q

Pox virus causes which viral STI and causes raised, pearl-like papules or nodules in pubic area/groin?

A

molluscum contagiosum

141
Q

Describe the classical presentation of herpes simplex.

A

clusters of inflamed papules and vesicles on outer surface of genitals resembling cold sores

142
Q

What is the name of the drug used in the treatment of herpes simplex virus?

143
Q

What is the mechanism of action of aciclovir?

A

A guanosine derivative, converted to triphosphate by infected host cells. Aciclovir triphosphate then inhibits DNA polymerase, terminating the nucleotide chain and inhibiting viral DNA replication.

144
Q

What is the mechanism by which HIV causes illness?

A
  • infects cells of the immune systems which carry CD4 receptors to allow HIV entry
  • causes depletion of CD4 T helper cells by direct viral killing of cells, apoptosis of uninfected ‘bystander cells,’ CD8+ cytotoxic T cell killing of infected CD4+ cells
  • abnormal B cell activation resulting in excess/inappropriate Ig production
  • CD4+ cells fall below 200 - risk of opportunistic infections and cancers
145
Q

Describe the mechanisms by which the drugs available for HIV work.

A
  • fusion inhibitor/R5 inhibitor
  • NRTI/NNRTI
  • integrase inhibitor
  • protease inhibitor
146
Q

What is HIV latency?

A

a state of reversibly non-productive infection of individual cells
long symptomatic period between initial infection and AIDS

147
Q

What are the two main clinical markers of HIV?

A
  1. CD4 cell count: risk of opportunistic infection increases sharply below 200/mm^3
  2. HIV-1 plasma RNA using ELISA: viral load test, below 10^4 low, above 10^5/ml high
148
Q

Describe the presentation of acute HIV infection.

A 
fever, malaise, headache, weight, N&amp;V
liver and spleen enlargement
lymphadenopathy
pharyngitis and oral sores/thrush
maculopapular rash
149
Q

What are the differential diagnoses of acute HIV infection?

A
  • infectious mononucleosis: rash, pharyngitis, lymphadenopathy
  • secondary syphilus
  • drug rash
  • viral infections: CMV, rubella, influenza, parvovirus
150
Q

What does HAART stand for, what is it and what is its aim?

A
  • highly active anti-retroviral treatment
  • ‘triple therapy’: 2 nucleosides + 1 drug from another class
  • aim: suppress viral load to undetectable and CD4 recovery
151
Q

List some of the short and long term toxicities associated with HAART treatment of HIV.

A
  • short: rash, hypersensitivity, CNS, GI, renal, hepatic

- long: lipodystrophy, renal, hepatic, lipid, bone

152
Q

What are the drug interactions associated with HAART?

A

mediated by CYP450 - PPIs, statins, antipsychotics

153
Q

Describe three microbiological characteristics of C. difficile.

A

anaerobic, gram+ve bacilli, spore forming, toxin producing, antibiotic resistant, part of normal bowel flora

154
Q

What parameters would you use to assess and classify the severity of CDAD?

A
  • colonic dilatation > 6cm
  • WCC > 15
  • creatinine > 1.5X baseline
  • temp > 38.5
  • immunosuppression
155
Q

What are the GI complications of CDAD

A

pseudomembranous colitis, toxic megacolon, perforation

156
Q

Which organisms commonly associated with CAP are normally resistant to beta-lactam therapy?

A

mycoplasma, legionella, chlamydia

Phase 3 (10 decks)

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