Respiratory Infection...............................

RESPIRATORY INFECTION.........................................................

1. RESPIRATORY TRACT INFECTIONS
Dr.SaraNeha
Department of Microbiology

3. UPPER RESPIRATORY TRACT
INFECTIONS
•Infections of airway
above glottis or vocal
cords
•Tonsillitis
•Pharyngitis
•Laryngitis
•Sinusitis
•Otitis media
•Rhinitis
1)Cough
2)Sore throat
3)Running nose
4)Nasal congestion
5)Headache
6)Low-grade fever
7)Facial pressure
8)Sneezing

4. Rhinitis or common cold
•Mostly caused by viruses:
•Rhinovirus
•Coronavirus
•Adenovirus
•Influenza virus
•Parainfluenza virus
•Human metapneumovirus
•Respiratory syncytial virus

5. Sinusitis
•Symptoms: Headache/facial pain, nasal mucus, Plugged nose
•Agents of acute sinusitis:
•Viruses (most common cause): Rhinoviruses, Influenza viruses,
Parainfluenza viruses
•Bacterial agents: Streptococcus pneumoniae, Haemophilus
influenzae, Moraxellacatarrhalis, Pseudomonas and other gram
negative bacilli (nosocomial sinusitis)
•Agents of chronic sinusitis: Obligate anaerobes, Staphylococcus
aureus

6. PHARYNGITIS & TONSILLITIS

7. PHARYNGITIS & TONSILLITIS

8. LARYNGITIS
•Influenza virus
•Parainfluenza virus
•Rhinovirus
•Adenovirus
•Coronavirus
•Human metapneumovirus
•Streptococcus pyogenes
•C. diphtheriae
•Epstein-Barr virus
Hoarseness of voice
Lowering & deepening of
voice

9. LARYNGOTRACHEOBRONCHITIS
(Croup)
Children, <3 years age
Inspiratory stridor
Hoarseness
Fever
Cough (barking)
Parainfluenza virus (M/C)
Influenza virus
Respiratory syncytial virus
Adenoviruses

10. Epiglottis
•Edema and inflammation of epiglottis and soft
tissue above vocal cords
•Age: children 2–6 years
•Symptoms: Fever, Difficulty in swallowing,
Inspiratory stridor
•Most common agent: Haemophilusinfluenzae
type b

11. Lower Respiratory Tract Infection
Community acquired Hospital acquired
PNEUMONIA

12. Community-acquired Pneumonia
(CAP)
•Streptococcus pneumoniae
•Mycoplasma pneumoniae
•Chlamydophila pneumoniae
•Chlamydia psittaci
•Legionella spp.
•Coxiella burnetii
•Viruses (Influenza, Adenovirus, Parainfluenza, RSV)

13. CURB-65score
-C(Confusion) = 1 point
-U(blood urea nitrogen >19 mg/dL) = 1 point
-R(respiratory rate >30 min) = 1 point
-B(BP <90/60) = 1 point
-65(Age ≥65 years) = 1 point
•Higher the score, greater is the mortality
•If the score ≤1, outpatient therapy is indicated
If the score >1, patient should be hospitalized

14. Hospital-acquired Pneumonia (hAP)
•VAP-Venticularassociated pneumonia,occurs
in patient that have been on mechanical
ventilation for more than 48 hours.
•Clinical signs-Purulanttracheal
discharge,fever, and respiratory distress in the
presence of microorganism.

15. CAUSATIVE ORGANISMS
Gram-negative bacilli (most common)
MDR non-fermenters
MDR Enterobacteriaceae
Staphylococcus aureus (both MRSA and MSSA)
S. pneumoniae (rarely, in early stage)
Influenza, adenovirus, parainfluenza, RSV

16. LOBAR PNEUMONIA

17. INTERSTITIAL PNEUMONIA

18. BRONCHITIS
•Inflammation of bronchus, which occurs
either as an extension of upper respiratory
tract infection such as influenza or may be
caused directly by bacterial agents such as
Bordetella.
•Common symptoms -fever, cough, sputum
production, and rarely croup-like features

19. BRONCHITIS
Bacterial agents:
B. pertussis
B. parapertussis
Mycoplasmapneumoniae
Chlamydophilapneumoniae
Viral agents:
Influenza viruses
Adenoviruses
Rhinoviruses
Coronaviruses

20. BRONCHIOLITIS
•Inflammation of the smaller airways (bronchioles)
•It presents as an acute viral infection that
primarily occurs in children less than 2 year
•Symptoms: Acute onset of wheeze, dyspnea,
cough, rhinorrhea, and respiratory distress
•Respiratory syncytial viruses account for 40–80%

21. BRONCHIOLITIS
•Respiratory syncytial viruses
•Parainfluenza viruses
•Rhinoviruses
•Influenza viruses
•Adenoviruses
•Enterovirus
•Human metapneumovirus

22. Laboratory Diagnosis
For URTI:
–Throat swab
–Nasopharyngeal aspirate
For LRTI:
•Sputum
•Induced sputum
•Tracheal aspirate
•Bronchoalveolarlavage (BAL)

23. Microscopy
•Albert staining
•Gram staining
•Acid fast staining
•GMS stain
•Immunofluorescence microscopy of
nasopharyngeal aspirate

25. Culture
•For bacteriological culture: Blood agar, chocolate agar and
MacConkeyagar
•For isolation of C. diphtheriae: Loeffler’sserum slope and
potassium telluriteagar
•For M. tuberculosis: LJ medium and incubated for up to 6–
8 weeks
•For fungal pathogen isolation: Sabourauddextrose agar
•Viral -Appropriate cell lines

26. CARROM COIN APPEARANCE OF
Streptococcus pneumoniae
SATELLITISM IN H. influenzae

27. COLONIES OF Candidaspecies ROUGH, TOUGH & BUFF COLONIES OF
Mycobacterium tuberculosis

28. FRIED EGG colonies of Mycoplasmaspp.

29. TREATMENT
•Community-acquired pneumonia (CAP)
Empiric regimen is determined by presence of co-
morbidity and prediction of prognosis by CURB-65
scoring system
•CAP, hospitalized (if CURB65 score >1):
-IV ceftriaxone plus azithromycin or
-IV levofloxacin
-Add vancomycin if CA-MRSA suspected

30. •CAP, outpatient (if CURB-65 score ≤1):
Oralazithromycinorazithromycin+amoxyclav
Orallevofloxacin

31. Hospital-acquired pneumonia (HAP)
•Empirical therapy: Gram-negative (e.g.
piperacillin-tazobactam or meropenem) +
Gram-positive coverage (e.g. vancomycin)
•Definitive therapy: The empirical treatment
should be tailored based on the organism
isolated and its