Current British guidelines need revision

Community acquired pneumonia is the most common reason for acute admission to hospital, with an estimated 50 000 cases occurring each year in the United Kingdom.1 Over 90% of these patients are aged over 65 years and the associated mortality is 16-40%.2 Streptococcus pneumoniae is still the most common causative organism, probably responsible for up to 40% of cases; Mycoplasma pneumoniae (3-23%), Haemophilus influenzae (5-8%), and Legionella pneumophila (3-6%) are the next commonest.2 “Atypical” pathogens are, however, becoming more prominent in old people, and current guidelines on antibiotic treatment may not be appropriate in this age group.

Until recently pneumonia due to atypical pathogens has been considered uncommon in old people: a review of 11 studies of pneumonia identified Chlamydia and Coxiella spp as the cause in only 2% of patients …