Infectious DiseaseRespiratory
Atypical Pneumonia (Legionella / Mycoplasma / Chlamydophila)
Clinical features + targeted testing, macrolide / tetracycline / fluoroquinolone, public health (Legionella).
Source: BTS 2023; IDSA
Step 1 of ~3
info
Recognise
Suspect when CAP + atypical features:
• Legionella: severe pneumonia + hyponatraemia + transaminitis + diarrhoea + confusion + history of travel / hotel / spa / cooling tower.
• Mycoplasma: young adults, prolonged cough, extra-pulmonary features (rash — erythema multiforme; haemolytic anaemia — cold agglutinin; encephalitis; transverse myelitis).
• Chlamydophila pneumoniae: prolonged sore throat → cough.
• Chlamydophila psittaci: bird exposure (parrots, pigeons).
• Coxiella burnetii (Q fever): farm / animal exposure.
Related
Curated clinical cross-links plus same-class fallbacks.
Drugs
- Clarithromycin 500mg (Atypical CAP) · Macrolide antibiotic
- Inclisiran · PCSK9-targeted siRNA
- Doxycycline 100mg (Acne / Rosacea) · Oral tetracycline antibiotic (anti-acne / anti-rosacea)
- Lymecycline 408mg (Acne) · Oral tetracycline antibiotic (anti-acne)
- Erythromycin 2% Topical · Topical macrolide antibiotic (anti-acne)
- Minocycline · Tetracycline Antibiotic
Pathways
- Infective Endocarditis · ESC 2023 Infective Endocarditis Guidelines; NICE NG41
- Suspected Bacterial Meningitis (Adult) · NICE NG240 (2024); NICE NG143 (paeds)
- Neutropenic Sepsis · NICE CG151; ASCO 2018
- Clostridioides difficile Colitis · NICE NG199 (2021); IDSA/SHEA 2021
- Returning Traveller — Fever · NaTHNaC; PHE; ESCMID 2018
- Malaria — Diagnosis & Management · PHE 2016; WHO 2023
Decision support only. Always apply local guidelines and clinical judgement.