Microbiology 2 and 3 - Microbiology of the Resp. tract Flashcards

1
Q

What are the causes of the classical flu?

A

Influenza A virusInfluenza B virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the cause of a flu like illness?

A

Parainfluenza viruses but many other causes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Does haemophilus influenzae cause flu?

A

Not a primary cause (it is a bacterium) but may be a secondary invader

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Complications of flu?

A

Primary influenzal pneumoniaSecondary bacterial pneumoniaBronchitisOtitis mediaInfluenza during pregnancy may also be associated with perinatal mortality, prematurity, smaller neonatal size and lower birth weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is flu treated?

A

Symptomatic (bed rest, fluids, paracetamol)Antivirals (only if patient is at risk of complications and when flu is circulating and early in disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What antivirals are used to treat flu?

A

OseltamivirZanamivir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are epidemics of flu associated with?

A

WinterMinor mutations in the surface proteins of the virus (antigenic drift)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the difference between epidemic and pandemic?

A

An epidemic occurs when a disease affects a greater number people than is usual for the locality or one that spreads to areas not usually associated with the disease. A pandemic is an epidemic of world-wide proportions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What type of flu can cause pandemics?

A

Influenza A only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What subtype of influenza A is avian flu?

A

H5N1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is influenza confirmed in the lab?

A

Direct detection of virus:PCR (nasopharyngeal swab, throat swab or other respiratory samples)Other labs/ hospitals may used immunofluorescence, antigen detection (near patient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Prevention of flu?

A

Killed vaccine (given to adult/ child (aged 6 months to 2 years) patients at high risk and healthy care workers)Live attenuated vaccine (more effective than killed vaccine in children aged 2-17, given to ALL children aged 2-5 and all primary school children administer intra-nasally)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When are antivirals used as a prophylaxis against flu?

A

After a contact with fluVery rarely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are 3 examples of atypical pneumonia?How are these treated?

A

Mycoplasma pneumoniaeCoxiella and Chlamydohila psittaciTetracycline and macrocodes e.g. clarithromycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Mortality of atypical pneumonias?

A

Varies with pathogen by generally lower than classical bacterial pneumonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How are the atypical pneumonias (mycoplasma, coxiella, psittaci) diagnosed?

A

By serology (send acute and convalescent bloods to lab)Virus detection (PCR on respiratory swabs/ secretions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Who tends to get mycoplasma pneumoniae?

A

Children and young adultsPerson to person spread

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What diseases does coxiella burnetti cause?

A

PneumoniaQ-fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is infection with coxiella burnetti associated with?

A

Sheep and goats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Complications of infection wit coxiella burnetti?

A

Culture negative endocarditis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What illness does infection with chlamoydophila psittaci cause?How does this usually present?

A

Psittacosis (parrot fever)Pneumonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What age do patients present with bronchiolitis?Symptoms

A

1st or 2nd year of lifeFeverCoryzaCoughWheezeSevere cases can cause grunting, decreased PaO2, intercostal/ sternal indrawing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Complications of bronchiolitis?

A

Respiratory and cardiac failure(especially if premature or pre-existing conditions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is usually the cause of Bronchiolitis?How is this confirmed?

A

Respiratory Syncytial VirusBy PCR on throat or perusal swab

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Therapy for bronchiolitis?

A

Supportive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is metapneumovirus?

A

A respiratory viral pathogen that causes acute respiratory tract infection in childrenMost children have antibody by age 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What diseases does metapneumovirus cause?

A

Second only to RSV in bronchiolitis2% of cases pf influenza-like illness Ranges in severity from mild to requiring ventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is metapneumovirus confirmed in the lab?

A

PCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is a cause of infantile pneumonia related to an STI?How is it diagnosed?

A

Chlamydia trachomatisPCR on urine of mother or perusal/ throat swabs of child

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does chlamoydophila pneumonias cause?

A

Mostly mild respiratory infecitonPerson to person spread

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the upper respiratory tract colonised with?

A

Gram positives:Alpha-haemolytic streptococci inc. strep pneumoniaeB-haemolytic streptococci inc. strep pyogenesStaph aureusGram negatives:Haemophilus influenzaeMoraxella catharalisMany others

32
Q

What are the 5 types of upper respiratory tract infections

A

SinusitisRhinitisPharyngitis (includes pharynx, tonsils and uvula)EpiglottitisLaryngitis

33
Q

What usually causes epiglottitis/

A

Haemophilus influenzae type B

34
Q

Clinical picture of epiglottitis?

A

Children (2-7):Acute onset (hours)Sore throatDroolingsevre croup/ stridorHigh tempAdult onset is days

35
Q

How do we test for epiglottitis?

A

Blood culture

36
Q

Why do we not test for epiglottis using a throat swab?

A

It can irritate the epiglottis further causing it to swell up further

37
Q

Treatment for epiglottis?

A

Usually admitted to ICU and treated with Ceftriaxone

38
Q

Are the conducting airways (trachea and bronchi) usually colonised?

A

No

39
Q

When do patients tends to get infection in their conducting airways (trachea and bronchi)?

A

Changes to airway e.g. trauma/ intubationAirway abnormalitiesVirulent pathogen

40
Q

What are the pathogenic causes of acute COPD exacerbation?

A

Can be environmentalHaemophilus influenzaeMoraxella catarrhalisStreptococcus pneumoniaeGram negativesVirus

41
Q

Why do patients with CF tend to get frequent infections?

A

Inefficient clearance and build-up of mucus

42
Q

What types of bacteria are often seen in CF patients?

A

Staph aureus. haemophilus influenzae, strep pneumoniae, pseudomonas aeruginosa, Burkholderia cepacia and MANY others

43
Q

What is whooping cough (pertussis)?

A

Acute tracheobronchitis

44
Q

What are the clinical features of whopping cough (pertussis)

A

Cold like symptoms for 2 weeksParoxysmal coughingRepeated voilent exhalations with severe inspiratory whoop, vomiting commonResidual cough for month or more

45
Q

What bacteria causes whooping cough?

A

Bordetella pertussis (gram negative coccobacillus)

46
Q

How is pertussis diagnosed?

A

Bacterial culture (pernasal swab)PCR (pernasal swab)Serology

47
Q

Treatment of pertussis?

A

Antibiotics if had cough for less than 21 days - clarithromycin (erythromycin if pregnant)

48
Q

Clinical features of CAP?

A

CoughIncreased sputumChest painDyspnoeaFeverCXR with infiltratesAcquired in the community

49
Q

Is legionella gram negative or gram positive?

A

Gram negative

50
Q

Clinical features of legionella pneumonia?

A

Flu like illness which may progress to severe pneumonia, with mental confusion, acute renal failure and GI symptoms

51
Q

How is legionella pneumonia spread?

A

No person to person spreadInhalation of contaminated water dropletsTherefore associated with shower heads, cooling towers, air conditioning

52
Q

Diagnosis of legionella pneumonia?

A

Legionella urinary antigen (detects serogroup 1 only)PCR available direct from sputum

53
Q

Treatment of legionella pneumonia?

A

Clarythromycin, erythromycin, levofloxacin

54
Q

What is the greatest risk for developing hospital acquired pneumonia?

A

Endotracheal intubation with mechanical ventilation (also risks with sedation, micro aspirations, aspirations of GI contents, immunosuppression)

55
Q

Microbiology of HAP?

A

60% = gram negative including E. coli, Klebsiella spp, pseudomonas app, CAP organisms, S aureus and anaerobes

56
Q

Treatment of a severe HAP?

A

IV amoxicillin, metronidazole and gentamicinStep down to PO co-trimoxazole + metronidazole

57
Q

Treatment of non-severe HAP?

A

PO amoxicillin + metronidazole

58
Q

What is the full name of PCP?

A

Pneumocystis jirovecii pneumonia

59
Q

What type of patients get this?

A

One of the most frequent and severe opportunistic infection in people with weakened immune systems e.g. aIDS, immunosuppression (people with a normal immune system can be asymptomatic with it either carrying it or eradication it)

60
Q

What type of organism is pneumocystitis jirovecii?

A

Fungus

61
Q

Does mycoplasma pneumonia cause a dry or wet cough?

A

Dry

62
Q

Symptoms of PCP?

A

FeverDry coughSOBFatigueHIV patients = sub-acute, low grade fever, severe pneumoniaNon-HIV = more acute high fever

63
Q

Diagnosis of PCP?

A

Microscopy (immunofluorescence of gargle)PCR

64
Q

Treatment of PCP?

A

Co-trimoxazole or pentamdine

65
Q

What are a list of causes of CAP?

A

Streptococcus pneumonia (Common)Haemophilus pneumoniae (common)Moraxella catarrhalis (common)Mycoplasma pneumonie (common, atypical)Chlamydias (pneumoniae (atypical), psiticci (atypical), trachomatis)PCPLegionella pneumoniae (atypical)Staphylococcus aureusCoxiella burnetti (atypical)Viruses

66
Q

Aside from PCP, what is another fungal chest infection?

A

Apergillus

67
Q

What causes aspergilus chest infection?

A

Usually aspergillum fumigates (common environmental fungus)

68
Q

What type of patients get aspergillus chest infection?

A

Immunocompromised/ supressed patients(causes severe pneumonia and invasive disease)

69
Q

What type of infection do immunocompetent patients infected by aspergillus get?

A

Localised pulmonary infectionAspergilloma (fungus ball) in pre-existing chest caivties

70
Q

How is aspergillus diagnosed?

A

Bronchoalveolar lavage ideally (fungal culture, PCR)Tissue (histopathology)

71
Q

Treatment of aspergillus?

A

Amphotericin BVoriconazoleSurgery

72
Q

Causes of TB?Appearance of TB?

A

Mycobacterium tuberculosisAcid alcohol fast bacilli with a thick waxy coat

73
Q

Pathogensis of TB?

A

Mycobacterium tuberculosis are engulfed by alveolar macrophages in alveoli but resist killing and multiply leading to a focus

74
Q

Types of TB?

A

90% asymptomatic and develop latent TB (alterations in immune function leads to reactivation and active TB)10% develop immediate active TB

75
Q

Clinical symptoms of TB?

A

Long term coughChest painSputum =?- haemoptysisWeakness or fatigueFever and chillsNight sweats

76
Q

Diagnosis of TB?

A

Microscopy of sputum/ tissueCulture on selective mediaPCRImmune reaction

77
Q

How is microscopy of mycobacterium tuberculosis prepared?

A

Ziehl-Neelsen (ZN) stain is used - red dye which is added to smear and heated to allow dye to penetrate waxy coat, acid/alcohol addedWaxy coat of mycobacterium retains the dye even after exposure to acid and alcohol