Pneumonia & Fungal Infectionsl Flashcards
Compre typical & atypical pneumonia
T: rapid onset, more severe symptoms, productive cough, dense consolidation on chest X-ray
S.pneumoniae, K.pneumoniae, H.influenzae, P.aeruginosa
AT: slower onset, less severe symptoms, nonproductive cough, patchy interstitial pattern on chest X-ray
Mycoplasma pneumoniae, chlamydophilo pneumoniae, chlamydia psittaci, Legionella pneumophilia, viruses & fungi.
Causative agents of community vs hospital-acqiured pneumonia
Strept.pneumoniae - C
Gram negative bacilli, S.aureus - H
Typing of S.pneumoniae is by …… using …..
Polysaccharide capsule
Specific antisera
Write a short note on virulence factors of S.pneumoniae
- Capsule, antiphagocytic
- IgA protease
- Pneumolysin, membrane damaging toxin
- Autolysin, breaks peptide cross-linking of peptidoglycan
Mention sites which pneumococci can invade
Blood stream, pleural cavity, meninges
The reaction used for typing of Strept.pneumoniae
Quellung reaction
Describe the character of sputum in S.pneumoniae & K.pneumoniae
S: rust-coloured , from blood coughed up from the lungs
K: currant-jelly sputum, thick, tenacious, blood-tinged
Diagnostic specimens of S.pneumoniae & H.influenzae
Sputum & BAL
Grwoth of S.pneumoniae is inhibited by……& colonies have ……. appearnce
Bile & optochin
Draughtsman
Compare the two vaccines of S.pneumoniae
13-valent pneumococcal conjugate vaccine, given to immunocompromised & children under age of 5 yrs.
23-valent pneumococcal vaccine, given to individuals 65 yrs or older or 50 yrs or older if chronic disease is present.
Factors required by H.influenza in culture
Heme (factor V)
NAD (factor X)
Mention virulence factors of H.influenzae
Antiphagocytic polysaccharide capsule, pili, IgA protease.
Enriched medium for H.influenzae
Chocolate agar
What is satellitism?
H.influenzae grows well around colonies of S.aureus
Write a short note about H.influenzae vaccination
Conjugated polysaccharide capsule against type b capsular polysaccharide given between 2 and 18 months of age.
Name Klebsiella community acquired pneumonia
Friedlander’s pneumonia
Mention virulence factors of Klebsiella
- Huge polysaccharide capsule, antiphagocytic
- LPS
- Adhesins
What is the specimen of Klebsiella & pseudomonas
Sputum
Effect of Klebsiella on blood & MacConckey’s agar
Non hemolytic
LF
Klebsiella typing is done by
Capsular antigen
Pseudomonas is a major cause of …..
Ventilator-associated pneumonia
Mention predisposing factors to pseudomonas pneumonia
Cystic fibrosis, COPD, significant break in first-line defences e.g. endotracheal tube
Mention effect of pseudomonas on different culture media.
Nutrient agar: greenish coloration with exopigment production
Blood agar: hemolytic
MacConkey’s agar: NLF
ST: it is used in epidemiological studies to trace source of pseudomonas infection
Pyocin typing
Stains for mycoplasma
Giemsa or leishman
Two exclusive human pathogens causing atypical pneumonia
Mycoplasma pneumoniae
Chlamydophila pneumoniae
MOT of mycoplasma and age group
Respiratory droplets
Young adults
How many serotypes of mycoplasma pneumoniae
1
Describe the pathogenesis of mycoplasma
Attaches & damages respiratory cilia, produces CARDS toxin which causes inflammation & airway dysfunction
Respiratory mucosa is not invaded, it produces hydrogen peroxide which can cause local damage
First choice for lab diagnosis of mycoplasma
PCR
Specimen for isolation of mycoplasma
Throat swabs & sputum
Culture media of mycoplasma must contain
Horse serum & yeast extract
Pathogens treated by tetracycline
Mycoplasma & Chlamydophila & Chlamydia
Diseases caused by legionella pneumophilia
Legionnaire’s disease
Pontaic fever
Substances required for growth of Legionella
Iron & cysteine
Virulence factors of Legionella
LPS Intracellular survival (facultative)
How does legionella survive in nature
Within free-living amoeba