Pneumonia

Last updated: January 17, 2026

Table Of Contents

Pneumonia
CURB-65 score
Pneumococcal vaccine
Community-acquired pneumonia (CAP)
Hospital-acquired pneumonia (HAP)
Mycoplasma pneumonia
Legionellosis
Coxiella Pneumonia (Q fever)
Pneumocystis jirovecii Pneumonia (PCP)
GBS Pneumonia
Klebsiella pneumonia

Pneumonia is a generalized infection of the lung parenchyma

Bottom Line Treatment for Pneumonia

Type of Pneumonia	Treatment	Alternative
Community-acquired (CAP)	3rd Generation Cephalosporin + Macrolide	Fluoroquinolone
Hospital-acquired (HAP)	Vancomycin + Piperacillin/Tazobactam
HIV/AIDS	TMP-SMX + Steroids + Cover for Community-acquired
Outpatient < 65 yo	Macrolide only

CURB-65 score

This score is used to determine whether a patient with pneumonia will be admitted.

Pneumococcal vaccine

Who to vaccinate?
- Anyone who requests a vaccination
- Prison inmates
- Older adults
- Asplenia
- Immunocompromised
- COPD
- Congestive Heart Failure
- Healthcare workers*

Community-acquired pneumonia (CAP)

Pneumonia that develops when the patient is not being hospitalized. The most common cause of pneumonia in all patient groups (excluding children) is Streptococcus pneumoniae. Treatment progression is based on symptom resolution and CXR.

Common pathogens causing Pneumonia

Pathogen	Association
Streptococcus pneumoniae	Most common
Staphylococcus aureus	Recent viral infection (influenza)
Haemophilus influenzae	COPD, smokers
Klebsiella pneumoniae	Alcoholism, diabetes, “currant jelly” sputum (hemoptysis from necrotizing disease)
Anaerobes	Poor dentition, aspiration, foul-smelling sputum
Mycoplasma pneumoniae	Young, healthy patients
Chlamydophila pneumoniae	Hoarseness
Legionella	Contaminated water sources, air conditioning, ventilation systems, gastrointestinal signs and symptoms
Chlamydia psittaci	Birds, placenta, sheep
Coxiella burnetti	Animals at the time of giving
Pneumocystis	AIDS < 200 CD4

Risk factors
- Cigarette smoking
- Fluid in lungs (effusion)
- Splenectomy
- Immune status
- Age (>60 yrs, < 2 yrs)
- Alcohol consumption
Symptoms
- Sputum (may not be present in atypical pneumonia)
- Fever
- Cough
Physical findings
- Rales and Rhonchi
- Dullness to percussion
- Egophony (increased resonance over affected fields if lobar pneumonia)
Investigations
- Chest X-ray: lobar consolidation (in streptococcal pneumonia); diffuse infiltrates (other causes)
When to admit
- Symptoms of respiratory compromise (hypoxia, hypercapnia, tachypnea)
- Sepsis (hypotension, tachycardia)
- Patient > 65 years old
- Significant concomitant illness (cancer, COPD, CHF)
- Immunodeficiency (HIV/AIDS, Asplenia, On steroids)
Emergency Treatment
- Oxygen (as needed)
- Fluid resuscitation (if hemodynamically unstable)
- Intubation
Outpatient treatment
- PO Macrolide OR Fluoroquinolone
  - Macrolide: Azithromycin, Clarithromycin
  - Fluoroquinolone: Moxiflocacin, Levofloxacin, Gatifloxacin (only IV)
Inpatient Treatment
- Third generation cephalosporin e.g. ceftriaxone AND Macrolide, OR
- Fluoroquinolone
ICU Treatment ***Add Beta-lactam to cover pseudomonas (if allergic to penicillin switch beta-lactam to aztreonam – effective against Gram-negatives)
- Beta-lactam AND Macrolide OR,
- Beta-lactam AND Fluoroquinolone OR,
- Aztreonam and Fluoroquinolone
Inpatient and ICU anti-pseudomonal coverage (Risk – Cystic fibrosis, Immunosuppressed)
- Pipercilin-tazobactam (Beta lactam)
- Ticarcilin-clavulanate **(Beta-lactam)
- Ceftazidime (3rd gen cephalosporin)
- Cefepime (4th gen cephalosporin)
- Tobramycin (Aminoglycoside)
- Amikacin (Aminoglycoside)
Supportive care
- Chest Physiotherapy (Incentive spirometry)
- Oxygen monitoring
- Oxygen supplementation
- Antipyretics
- Analgesia
- Proper hydration
- Diet and activity

Hospital-acquired pneumonia (HAP)

Pneumonia that develops if the patient has been hospitalized for > 48 hours. Very important to get sputum cultures. Should always be empirically treated with coverage for Pseudomonas and MRSA (broad enough to cover other causes)

Empiric Treatment
- Anti-psuedomonals: Ceftazidime, Cefipime, Pipericilin-tazobactam, ticarcilin-clavulanate, Tobramycin, Amikacin AND,
- Anti-MRSA: Vancomycin, Linezolid

Mycoplasma pneumonia

“Walking pneumonia”. The most common pneumonia in teenagers and young adults. Has mild symptoms of cough, coryza, and low-grade fever with a complete interstitial pneumonia picture on chest X-ray.

Investigations
- Chest X-ray: interstitial infiltrates
- Cold agglutinin assay: best diagnostic test
Treatment
- Azithromycin

Legionellosis

Usually occurs in older adults and smokers. Classic risk factors in air-conditioning. Will have additional gastrointestinal symptoms (nausea, diarrhea) and neurological symptoms (incoordination), with relative bradycardia

Investigations
- Legionella urine antigen
Treatment
- Doxycycline or Macrolide

Coxiella Pneumonia (Q fever)

Pneumonia after exposure to sheep placenta. The diagnosis is serology. Treatment is doxycycline

Pneumocystis jirovecii Pneumonia (PCP)

Common in AIDs patients. Tends to be very hypoxic (+ HIV/AIDS status and severity is an indication to test)

Investigations
- Chest X-ray
- Bronchoalveolar lavage: Best diagnostic
Treatment
- TMP/SMX OR Pentamidine (if sulfur allergy)
***Dapsone and Atovaquone are NOT USED FOR THERAPY (only for prophylaxis)

GBS Pneumonia

#1 cause of pneumonia and sepsis in neonates. Mothers will be GBS + (with poor prenatal care, did not get penicillin). Can be fatal. Can also cause meningitis.

Treatment
- Gentamicin OR Rifampicin

Klebsiella pneumonia

Associated with alcoholics. “Currant jelly sputum”

Treatment
- 3rd gen cephalosporin (Ceftriaxone, Cefotaxime)

Reference Intervals ›

Biochemistry

ACTH	P: <80 ng/L
ALT	P: 5–35 U/L
Albumin	P: 35–50 g/L
Aldosterone	P: 100–500 pmol/L
Alk. phosphatase	P: 30–130 U/L
α-Amylase	P: 0–180 IU/dL
α-Fetoprotein	S: <10 kU/L
Angiotensin II	P: 5–35 pmol/L
ADH	P: 0.9–4.6 pmol/L
AST	P: 5–35 U/L
Bicarbonate	P: 24–30 mmol/L
Bilirubin	P: 3–17 μmol/L
BNP	P: <50 ng/L
CRP	P: <10 mg/L
Calcitonin	P: <0.1 mcg/L
Calcium (ionized)	P: 1.0–1.25 mmol/L
Calcium (total)	P: 2.12–2.60 mmol/L
Chloride	P: 95–105 mmol/L
Cholesterol	P: <5.0 mmol/L
VLDL	P: 0.128–0.645 mmol/L
LDL	P: <2.0 mmol/L
HDL	P: 0.9–1.93 mmol/L
Cortisol AM	P: 450–700 nmol/L
Cortisol Midnight	P: 80–280 nmol/L
CK ♂	P: 25–195 U/L
CK ♀	P: 25–170 U/L
Creatinine	P: 70–100 μmol/L
Ferritin	P: 12–200 mcg/L
Folate	S: 2.1 mcg/L
FSH	P: 2–8 U/L ♂; >25 menopause
GGT ♂	P: 11–51 U/L
GGT ♀	P: 7–33 U/L
Glucose (fasting)	P: 3.5–5.5 mmol/L
Growth hormone	P: <20 mu/L
HbA1C (DCCT)	B: 4–6%
HbA1C (IFCC)	B: 20–42 mmol/mol
Iron ♂	S: 14–31 μmol/L
Iron ♀	S: 11–30 μmol/L
Lactate (venous)	P: 0.6–2.4 mmol/L
Lactate (arterial)	P: 0.6–1.8 mmol/L
LDH	P: 70–250 U/L
LH	P: 3–16 U/L
Magnesium	P: 0.75–1.05 mmol/L
Osmolality	P: 278–305 mosmol/kg
PTH	P: 0.8–8.5 pmol/L
Potassium	P: 3.5–5.3 mmol/L
Prolactin ♂	P: <450 U/L
Prolactin ♀	P: <600 U/L
PSA	P: 0–4 mcg/mL
Protein (total)	P: 60–80 g/L
Red cell folate	B: 0.36–1.44 μmol/L
Renin (erect)	P: 2.8–4.5 pmol/mL/h
Renin (recumbent)	P: 1.1–2.7 pmol/mL/h
Sodium	P: 135–145 mmol/L
TBG	P: 7–17 mg/L
TSH	P: 0.5–4.2 mU/L
T4	P: 70–140 nmol/L
Free T4	P: 9–22 pmol/L
TIBC	S: 54–75 μmol/L
Triglycerides	P: 0.50–2.3 mmol/L
T3	P: 1.2–3.0 nmol/L
Troponin T	P: <0.1 mcg/L
Urate ♂	P: 210–480 μmol/L
Urate ♀	P: 150–390 μmol/L
Urea	P: 2.5–6.7 mmol/L
Vitamin B12	S: 0.13–0.68 nmol/L
Vitamin D	S: 50 nmol/L

Arterial Blood Gases

pH	7.35–7.45
PaCO₂	4.7–6.0 kPa
PaO₂	>10.6 kPa
Base excess	±2 mmol/L

Urine

Cortisol (free)	<280 nmol/24h
Hydroxyindole acetic acid	16–73 μmol/24h
Hydroxymethylmandelic acid	16–48 μmol/24h
Metanephrines	0.03–0.69 μmol/mmol cr.
Osmolality	350–1000 mosmol/kg
17-Oxogenic steroids ♂	28–30 μmol/24h
17-Oxogenic steroids ♀	21–66 μmol/24h
17-Oxosteroids ♂	17–76 μmol/24h
17-Oxosteroids ♀	14–59 μmol/24h
Phosphate (inorganic)	15–50 mmol/24h
Potassium	14–120 mmol/24h
Protein	<150 mg/24h
Protein/creatinine ratio	<3 mg/mmol
Sodium	100–250 mmol/24h

Haematology

WCC	4.0–11.0 ×10⁹/L
RBC ♂	4.5–6.5 ×10¹²/L
RBC ♀	3.9–5.6 ×10¹²/L
Hb ♂	130–180 g/L
Hb ♀	115–160 g/L
PCV ♂	0.4–0.54 L/L
PCV ♀	0.37–0.47 L/L
MCV	76–96 fL
MCH	27–32 pg
MCHC	300–360 g/L
RDW	11.6–14.6%
Neutrophils	2.0–7.5 ×10⁹/L (40–75%)
Lymphocytes	1.0–4.5 ×10⁹/L (20–45%)
Eosinophils	0.04–0.44 ×10⁹/L (1–6%)
Basophils	0–0.10 ×10⁹/L (0–1%)
Monocytes	0.2–0.8 ×10⁹/L (2–10%)
Platelets	150–400 ×10⁹/L
Reticulocytes	0.8–2.0% / 25–100 ×10⁹/L
Prothrombin time	10–14 s
APTT	35–45 s

Paediatric

Pulse Rate (bpm)
Neonate	140–160
Infant <1yr	120–140
1–5 years	110–130
5–12 years	80–120
>12 years	70–100
Respiratory Rate (tachypnoea)
0–2 months	≥60/min
2–12 months	≥50/min
1–5 years	≥40/min
>5 years	≥30/min
Blood Pressure (mmHg)
Term	65/45
1 year	75/50
4 years	85/60
8 years	95/65
10 years	100/70
Weight Formulas
3–12 months	(a + 9)/2 kg
1–6 years	2a + 8 kg
>6 years	(7a − 5)/2 kg
Haemoglobin (g/dL)
Term newborn	13–20
1 month	11–18
2 months	10–15
1–2 years	10–13
>2 years	11–14
MUAC (6 months–5 years)
Obese	>17.5 cm
Normal	13.5–17.4 cm
At risk	12.5–13.4 cm
Moderate malnutrition	11.5–12.4 cm
Severe malnutrition	<11.5 cm
Developmental Milestones
Social smile	1.5 months
Head control	4 months
Sits unsupported	7 months
Crawls	10 months
Stands unsupported	10–12 months
Walks	12–13 months
Talks	18 months
CSF WBC (/mm³)
Term newborn	0–25
>2 weeks	0–5

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