Microbiology

Question 1

what is the triad for legionella pneumonia

Answer 1

pneumonia + lymphopenia, hyponatraemia and deranged LFTs

Question 2

how is legionella causing pneumonia initially diagnosed

Answer 2

diagnositic test of choice:urinary antigen
chest x-ray findings are non-specific but may include:
a mid-to-lower zone predominance of patchy consolidation
pleural effusions in around 30%

Question 3

what are the symptoms of legionnaires disease

Answer 3

flu-like symptoms including fever (present in > 95% of patients)
dry cough
relative bradycardia
confusion
lymphopaenia
hyponatraemia
deranged liver function tests
pleural effusion: seen in around 30% of patients

Question 4

how is legionnaires disease managed

Answer 4

treat with erythromycin/clarithromycin