Strep pneum. Flashcards
1
Q
A
2
Q
What is the historical first-line treatment for pneumococcal infections?
A
Penicillin (IV or oral)
Penicillin has been used historically for pneumococcal infections but faces increasing resistance.
3
Q
When can penicillin still be used for pneumococcal infections?
A
If the strain is penicillin-susceptible and the patient has a mild infection
High-dose IV penicillin G may be used for serious infections if susceptibility is known.
4
Q
What is preferred over penicillin for respiratory infections and why?
A
Amoxicillin due to better oral bioavailability
Amoxicillin is the first-line treatment for community-acquired pneumonia (CAP) in outpatients.
5
Q
What are the common uses for amoxicillin?
A
- Mild-moderate pneumonia (if susceptible)
- Otitis media
- Sinusitis
6
Q
What are ceftriaxone and cefotaxime used for?
A
Moderate to severe pneumococcal infections
They are first-line treatments for pneumococcal meningitis, often combined with vancomycin.
7
Q
What is the role of cefuroxime?
A
Alternative oral cephalosporin for less severe pneumonia
It is sometimes used when oral therapy is needed.
8
Q
Why are cephalosporins used instead of penicillin?
A
Due to penicillin resistance and coverage of more resistant strains
9
Q
When are macrolides like azithromycin used?
A
When penicillin allergy is present
Azithromycin is used for mild CAP, otitis media, sinusitis, and atypical pathogens.
10
Q
What is a significant concern regarding macrolides for pneumococcus?
A
Increasing macrolide resistance (~30% of S. pneumoniae strains)
Macrolides should not be used alone for serious pneumococcal infections.
11
Q
What conditions warrant the use of fluoroquinolones?
A
- Severe pneumonia
- Penicillin-resistant pneumococcus
- Patients with comorbidities (COPD, diabetes, immunosuppression)
12
Q
Why are fluoroquinolones not first-line treatments?
A
Growing fluoroquinolone resistance and risks of tendon rupture, QT prolongation, and C. difficile infection
13
Q
In what scenarios can doxycycline be used?
A
- Mild community-acquired pneumonia (CAP)
- Outpatient treatment in penicillin-allergic patients
- Atypical pneumonia coverage
14
Q
Why is doxycycline not preferred for pneumococcus?
A
Common resistance to S. pneumoniae and unreliability for serious infections
15
Q
When is vancomycin used?
A
When penicillin-resistant S. pneumoniae is suspected and for severe infections
It is often combined with ceftriaxone for meningitis.
16
Q
Why is vancomycin not used for all pneumococcal infections?
A
Narrow-spectrum drugs are preferred to prevent resistance
17
Q
When is Penicillin (IV/oral) used?
A
If strain is susceptible, mild infections
Historical first-line, but resistance is an issue.
18
Q
What is the first-line use of Amoxicillin?
A
First-line for pneumonia, otitis media
Better oral absorption than penicillin.
19
Q
What conditions are Ceftriaxone (IV) and Cefotaxime (IV) used for?
A
Severe pneumonia, meningitis, bacteremia
Covers resistant S. pneumoniae.
20
Q
When is Cefuroxime (Oral) indicated?
A
Alternative to amoxicillin for mild pneumonia
Oral cephalosporin option.
21
Q
What is Azithromycin used for?
A
Mild pneumonia, atypical coverage, penicillin allergy
Increasing resistance limits use.
22
Q
When should Levofloxacin or Moxifloxacin be used?
A
Severe pneumonia, high resistance concerns
Stronger, but resistance & side effects.
23
Q
What is the use of Doxycycline?
A
Mild pneumonia, penicillin allergy
Not reliable due to resistance.
24
Q
When is Vancomycin used?
A
Severe infections, meningitis, drug-resistant cases
Last resort for resistant S. pneumoniae.
25
What is the Gram stain characteristic of Streptococcus pneumoniae?
Gram-Positive
## Footnote
It stains purple due to its thick peptidoglycan cell wall.
26
What type of hemolysis does Streptococcus pneumoniae exhibit on blood agar?
Alpha-Hemolytic
## Footnote
It produces partial hemolysis, resulting in greenish discoloration.
27
What is the role of the polysaccharide capsule in Streptococcus pneumoniae?
Helps evade the immune response
## Footnote
It particularly aids in avoiding phagocytosis by macrophages.
28
Is Streptococcus pneumoniae catalase-positive or catalase-negative?
Catalase-Negative
## Footnote
This characteristic differentiates it from staphylococci.
29
What is the most common cause of bacterial pneumonia in adults?
Community-acquired pneumonia (CAP)
## Footnote
Streptococcus pneumoniae is the major pathogen responsible.
30
What serious infection of the meninges is caused by Streptococcus pneumoniae?
Meningitis
## Footnote
This can lead to neurological damage or death.
31
What is otitis media?
Middle ear infection
## Footnote
It is especially common in children and caused by Streptococcus pneumoniae.
32
What type of infection is sinusitis?
Infection of the sinuses
## Footnote
It can lead to sinus pressure and headache.
33
What is bacteremia?
Bloodstream infection
## Footnote
Often seen in severe cases of pneumonia or meningitis.
34
How does smoking affect the risk of pneumococcal pneumonia?
Increases risk due to ciliary dysfunction, impaired immune response, and increased bacterial colonization
## Footnote
Smoking damages the cilia, reduces immune cell activity, and raises colonization rates.
35
What are some examples of immunocompromised individuals at higher risk for severe pneumococcal infections?
Patients with HIV, cancer, organ transplants, or receiving immunosuppressive treatments
## Footnote
Their immune systems are less able to fight off infections.
36
What is one consequence of pneumococcal infections in immunocompromised individuals?
Higher risk of bacteremia and meningitis
## Footnote
These infections can be more severe and spread to the bloodstream and central nervous system.
37
What is a significant risk factor for pneumococcal infections in older adults?
Declining immune function with age
## Footnote
This includes reduced T-cell activity and immunoglobulin production.
38
What chronic diseases are common in the elderly that increase their risk for pneumococcal infections?
* Chronic obstructive pulmonary disease (COPD)
* Diabetes
* Heart disease
* Asthma
## Footnote
These conditions make the lungs more susceptible to infection.
39
What happens to the respiratory tract's ability to clear bacteria as people age?
It becomes less efficient
## Footnote
This increases the chances of pneumonia.
40
True or False: Older adults tend to develop less severe pneumonia.
False
## Footnote
They tend to develop more severe and complicated pneumonia.
41
What is Invasive Pneumococcal Disease (IPD)?
Cases where the bacteria invade sterile sites like the blood, cerebrospinal fluid (CSF), or other tissues.
## Footnote
It includes serious conditions such as bacteremia, pneumococcal meningitis, and pneumococcal endocarditis.
42
What are the three types of conditions included in Invasive Pneumococcal Disease?
* Bacteremia
* Pneumococcal meningitis
* Pneumococcal endocarditis
## Footnote
These conditions involve serious infections affecting sterile sites.
43
What is Bacteremia?
Bacterial infection in the blood.
## Footnote
It is a serious condition that falls under Invasive Pneumococcal Disease.
44
What is Pneumococcal meningitis?
Infection of the meninges.
## Footnote
This condition is part of Invasive Pneumococcal Disease and can lead to severe complications.
45
What is Pneumococcal endocarditis?
Infection of the heart valves.
## Footnote
This is another serious manifestation of Invasive Pneumococcal Disease.
46
What is Non-invasive Pneumococcal Disease?
Diseases like otitis media, sinusitis, and non-bacteremic pneumonia where bacteria do not invade deeper tissues.
## Footnote
These conditions are localized infections in the respiratory system.
47
Name three examples of Non-invasive Pneumococcal Disease.
* Otitis media
* Sinusitis
* Non-bacteremic pneumonia
## Footnote
These diseases are less severe compared to invasive forms.
48
What drug class does Penicillin belong to?
Beta-lactam antibiotic (Penicillin subclass)
## Footnote
Penicillin is a well-known antibiotic used primarily against bacterial infections.
49
What is the mechanism of action of Penicillin?
Inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs)
## Footnote
This prevents the cross-linking of peptidoglycan, essential for bacterial cell wall integrity.
50
Which bacteria are Penicillin effective against?
Gram-positive bacteria:
* Streptococcus pneumoniae
* Streptococcus pyogenes
* Enterococcus
## Footnote
Penicillin has limited efficacy against Gram-negative bacteria and does not cover MRSA.
51
What are the common clinical uses of Penicillin?
Historically first-line for pneumococcal infections; used if strain is susceptible; IV Penicillin G for serious infections
## Footnote
Examples include pneumococcal meningitis.
52
What are the side effects of Penicillin?
Allergic reactions, GI upset, hemolytic anemia
## Footnote
Allergic reactions can range from mild rashes to severe anaphylaxis.
53
What drug class does Amoxicillin belong to?
Aminopenicillin (Beta-lactam)
## Footnote
Amoxicillin is a commonly prescribed antibiotic with a broader spectrum than Penicillin.
54
What is the mechanism of action of Amoxicillin?
Inhibits PBPs, disrupting peptidoglycan synthesis
## Footnote
Similar to Penicillin, it affects bacterial cell wall formation.
55
What is the spectrum of activity of Amoxicillin?
Gram-positives and more Gram-negative coverage:
* H. influenzae
* E. coli
* Proteus mirabilis
## Footnote
It does not cover MRSA.
56
What are the clinical uses of Amoxicillin?
First-line for mild-to-moderate pneumonia, otitis media, sinusitis, bronchitis
## Footnote
It has better oral bioavailability compared to Penicillin.
57
What are the side effects of Amoxicillin?
Rash, GI upset, allergic reactions
## Footnote
Rash is especially noted in patients with Epstein-Barr virus infection.
58
What class do Cephalosporins belong to?
Beta-lactams
## Footnote
Cephalosporins are a significant class of antibiotics with various generations.
59
What is the mechanism of action of Cephalosporins?
Inhibits PBPs, preventing cell wall synthesis
## Footnote
This is similar to both Penicillin and Amoxicillin.
60
What are the notable generations of Cephalosporins for pneumococcal infections?
Ceftriaxone (3rd gen, IV), Cefotaxime (3rd gen, IV), Cefuroxime (2nd gen, oral)
## Footnote
Ceftriaxone and Cefotaxime are used in severe infections, while Cefuroxime is an alternative for mild pneumonia.
61
What are the side effects of Cephalosporins?
Allergic reactions, GI upset, biliary sludging (Ceftriaxone)
## Footnote
Biliary sludging is particularly concerning in neonates.
62
What class of antibiotics do Macrolides belong to?
Macrolide antibiotic
## Footnote
Examples include Azithromycin and Clarithromycin.
63
What is the mechanism of action of Macrolides?
Inhibits 50S ribosome, preventing bacterial protein synthesis
## Footnote
This action inhibits the growth of bacteria by blocking protein production.
64
What is the spectrum of activity of Macrolides?
Covers Gram-positives and atypicals:
* S. pneumoniae
* Mycoplasma
* Chlamydia pneumoniae
* Legionella
## Footnote
There is increasing resistance in *S. pneumoniae*.
65
What are the clinical uses of Macrolides?
Mild community-acquired pneumonia, atypical pneumonia coverage, used in penicillin-allergic patients
## Footnote
They are often chosen for patients who cannot tolerate beta-lactams.
66
What are the side effects of Macrolides?
QT prolongation, GI upset
## Footnote
GI upset is most common with erythromycin.
67
What drug class do Fluoroquinolones belong to?
Fluoroquinolone antibiotic
## Footnote
Examples include Levofloxacin and Moxifloxacin.
68
What is the mechanism of action of Fluoroquinolones?
Inhibits DNA gyrase (topoisomerase II and IV), blocking DNA replication
## Footnote
This prevents bacterial cell division.
69
What is the spectrum of activity of Fluoroquinolones?
Covers S. pneumoniae, Gram-negatives, atypicals
## Footnote
They are stronger than macrolides but should be used judiciously to prevent resistance.
70
What are the clinical uses of Fluoroquinolones?
Severe pneumonia requiring hospitalization, when first-line options fail
## Footnote
They are reserved for more serious infections.
71
What are the side effects of Fluoroquinolones?
Tendon rupture, QT prolongation, GI side effects
## Footnote
The risk of tendon rupture is especially high in the elderly or those on steroids.
72
What drug class does Doxycycline belong to?
Tetracycline antibiotic
## Footnote
It is a broad-spectrum antibiotic used for various infections.
73
What is the mechanism of action of Doxycycline?
Inhibits 30S ribosomal subunit, blocking protein synthesis
## Footnote
This action prevents bacterial growth.
74
What is the spectrum of activity of Doxycycline?
Covers S. pneumoniae, atypicals, MRSA (skin infections)
## Footnote
It is not as reliable as beta-lactams.
75
What are the clinical uses of Doxycycline?
Mild pneumonia in penicillin-allergic patients, atypical pneumonia
## Footnote
It is often used when patients cannot take standard antibiotics.
76
What are the side effects of Doxycycline?
Photosensitivity, GI upset
## Footnote
It should be avoided in pregnancy and children under 8 years due to potential tooth discoloration.
77
What drug class does Vancomycin belong to?
Glycopeptide antibiotic
## Footnote
Vancomycin is critical for treating serious Gram-positive infections.
78
What is the mechanism of action of Vancomycin?
Binds D-Ala-D-Ala of peptidoglycan precursors, blocking cell wall synthesis
## Footnote
This action is crucial for combating resistant bacterial strains.
79
What is the spectrum of activity of Vancomycin?
Strong Gram-positive coverage:
* MRSA
* Resistant S. pneumoniae
## Footnote
It does not cover Gram-negative bacteria.
80
What are the clinical uses of Vancomycin?
Severe, drug-resistant pneumococcal infections, meningitis, MRSA pneumonia
## Footnote
It is often used in combination with other antibiotics for enhanced efficacy.
81
What are the side effects of Vancomycin?
Nephrotoxicity, ototoxicity, 'Red Man Syndrome'
## Footnote
Red Man Syndrome is a histamine reaction due to rapid IV infusion.
82
What is key in preventing pneumococcal infections?
Vaccination
## Footnote
Vaccines such as PCV13 and PPSV23 help reduce the burden of disease.
83
Which vaccines are mentioned as helpful in preventing pneumococcal infections?
* PCV13
* PPSV23
## Footnote
These vaccines are essential for reducing the incidence of pneumococcal disease.
84
How does smoking affect the risk of pneumococcal disease?
Increases the risk of infection
## Footnote
Quitting smoking significantly reduces the risk of pneumococcal disease.
85
What action can significantly reduce the risk of pneumococcal disease?
Quitting smoking
## Footnote
Smoking cessation is crucial for lowering infection risk.
86
What is important for managing the risk of pneumococcal infections in high-risk individuals?
Proper management of chronic conditions and immunization
## Footnote
Conditions like diabetes and COPD need careful management.
87
Who are considered high-risk individuals for pneumococcal infections?
* The elderly
* Immunocompromised patients
## Footnote
These groups should receive targeted immunization to prevent infections.
88
Where does *S. pneumoniae* normally colonize?
The nasopharynx
## Footnote
*S. pneumoniae* typically remains on mucosal surfaces.
89
In which populations can *S. pneumoniae* breach mucosal defenses?
Immunocompromised individuals, children, elderly
## Footnote
These groups are at higher risk for systemic infections.
90
What serious conditions can result from *S. pneumoniae* breaching mucosal defenses?
* Meningitis
* Bacteremia
* Pneumonia with pleural effusion
## Footnote
These conditions arise due to systemic infections.
91
What characterizes pneumococcal meningitis?
* Purulent inflammation
* Massive neutrophil infiltration
* High amount of pus in CSF
* Increased intracranial pressure
## Footnote
These features contribute to severe symptoms.
92
What are common symptoms of increased intracranial pressure in meningitis?
* Headache
* Neck stiffness
* Photophobia
* Altered mental status
## Footnote
These symptoms indicate severe neurological distress.
93
What is the recommended treatment for pneumococcal meningitis?
* High-dose ceftriaxone
* Vancomycin
* Dexamethasone
## Footnote
This combination addresses potential antibiotic resistance and reduces inflammation.
94
Fill in the blank: Pneumococcal meningitis is characterized by _______ due to massive neutrophil infiltration.
[Purulent inflammation]
95
True or False: *S. pneumoniae* can only cause local infections.
False
## Footnote
*S. pneumoniae* can cause systemic infections if it breaches mucosal barriers.
96
What leads to symptoms like headache and neck stiffness in pneumococcal meningitis?
Increased intracranial pressure
## Footnote
This pressure results from purulent inflammation and neutrophil infiltration.
