PNEUMONIA

( TYPICAL/ATYPICAL)

PNEUMONIA

• Insults

• Tissue response

• Mode of spread

• Classification

• Causative agents

• Clinical features

• Complications

• Differential diagnosis

• Investigations

• Treatment

• Poor prognosis

• References

RISK FACTORS

• Viral>>>Staph.aureus, G-ve bacilli
• Cigarettes/C.O.P.D>>>Impair mucociliary

function & phagocytosis

• Alcohol
• Head trauma
• Anasthaesia
• C.N.S lesions>>>decreased conciousness,dec

gag reflex>>>>>>>>>>ASPIRATION

• Foreign body/ tumours>>>Impair bronchial

drainage>>>Infection

INSULTS

• Dec leucocytes/ dec Ig>>>Recurrent

Pneumonia

• Steroids/Immunosuppression>>>opportuni

stic infections

• Severely ill
Ventillators
I.C.U
N.G tubes
A/B
Surgery>>>Nosocomial infections

TISSUE RESPONSE

. Strep. Pneumoniae/ H. Influenza:

lobar consolidation (NO tissue necrosis)

. Staph. Aureus/ G-ve bacilli:

Necrosis>>>cavitation (abcess), peribonchial

. Atypical: Viruses

Mycoplasma Pneumonia

Chlamydia Pneumonia/ Psittica

Legionella Pneumophila

Coxella Burnetti>>>>>>

Intrestitial, diff, bilateral

. Mycobacterium Tuberculosis/ Fungi:

Slow granulation.

MODE OF SPREAD

• Inhalation
• Aspiration
• Bld. stream

CLASSIFICATION

• Community
• Nosocomial

• Radiological
• Microbiological

• Immunocompromized
• Aspiration
• Recurrent

COMMUNITY AQUIRED

PNEUMONIA

Increase in winter( viruses & close contact)

• Strep.pneumonia 60% (G + C)

• H.influenza 10% (G-CB) >C.O.P.D

• Moraxella Catarrhalis (G-C) >C.O.P.D

• ATYPICAL: Legionella pneumophila(G-B)
Mycoplasma pneumonia
Chlamydophila
Viruses

• Staph. Aureus & G-ve Bacilli>>> less common
Staph (influenza), Klebsiella & G-ve (alcohol)

HOSPITAL ACQUIRED

PNEUMONIA

• Second most common nosocomial

infection

• Very ill>>> Increased mortality
• Polymicrobial: G-B (pseudomonas,

Klebsiella, E.Coli)

Anaerobes
Staph. Aureus
Pneumococci & others also

PNEUMONIA IN

IMMUNOCOMPROMIZED

Opportunistic organisms :
• Bact. : Nocardia/ Legionella
• Mycobacterium :M. Avium/

Intercellularae

• Viruses:CMV/ Herpes zoster
• Fungi: Candida/ Aspergillus
• Protozoa: Pneumocystis

carinii(Jeroveci)/ Toxoplasma gondii

CLINICAL FEATURES

• Symptoms: Fever, chills, cough,

haemoptysis, pleurisy, s.o.b, toxic.

• Examination: Consolidation.

VS. Atypical pneumonia.

COMPLICATIONS

• Hypoxia.
• Cardiopulmonary failure.
• Lung abcess.
• Empyema.
• Spread of infection.
• Lobar collapse
• Thromboembolism
• ARDS, renal failure, multiorgan failure

DIFFERENTIAL DIAGNOSIS

• Pulmonary infarction

• Tuberculosis

• Atelectasis

• Lung tumors

• Bronchiectasis

• Pulmonary oedema

• Hypersensitivity reactions: chemicals/ drugs

• Sarcoidosis

• Vasculitis

• Pulmonary hge

INVESTIGATIONS

• C.B.C: WBC/ differential
• C.X.R: consolidation/abcess/ effusion
• Sputum
• Pleural tap/ biopsy
• Bronchoscopy/ Lavage/ Biopsy
• ABG
• Bld. Culture
• Cold agglutinins
• Urinalysis

TREATMENT

• Hydration

• Analgesics/ antipyretics

• Oxygen

• Physiotherapy

• Antibiotics (clinical setting & CXR):

1- Community acquired ( bact.):

Penicillins- Amoxicillin- Clavulanic acid

2

nd

generation Cephalosporins

Trimethoprim- Sulphamethoxazole

Macrolides

Fluoroquinolones (Ciprofloxacin)

TREATMENT (cont’d)

• Antibiotics (cont’d):
2- Atypical : Erythromycin
3- G-ve : 3

rd

generation Cephalosporins +

Gentamycin, Pipracillin- tazobactam,
meropenum, imipenum- cilastatin.

4- Staph. Aureus : Augmentin/ cefuroxime/

Flucloxacillin, Vancomycin

5- Aspiration : Penicillin/ Clindamycin

RISK FACTORS FOR

MORTALITY

• Age >65 y.
• Presence of coexisting dis. : DM, COPD,

CRF, CCF, CLD, aspiration, altered mental

status, post splenectomy, alcohol.

• Physical : BP <90/60, temp. >38.3,

Extrapulm. Infection

• Lab findings : Leucocytes<4,000/

>30,000, PaO2<60 / PaCO2 >50, mech.

Vevt., Creatinine>1.2, Multilobar, spread,

Sepsis.

REFERENCES

• Davidson’s principles & practice of

medicine

• Scientific American Medicine
• UptoDate 2009