The spectrum of pneumonia in 1983 at the Riyadh Armed Forces Hospital.

The agents causing pneumonia have been assessed in 112 adult patients admitted to the Armed Forces Hospital in Riyadh during a period of one year: pathogens were identified in 78 patients (69.6%). Sputum culture produced a significant isolate in 60 patients (53.5%), and in 17 (15.2%) the causative agent was suggested by serological tests. Streptococcus pneumonia was the commonest infecting agent (21.4%). Pneumonia due to Mycobacterium tuberculosis was diagnosed in eight patients, to Mycoplasma pneumoniae in seven, to Chlamydia psittaci in two and to Legionella pneumophila in one. Three renal transplant patients had pneumonia caused by Staphylococcus aureus, cytomegalovirus and Pneumocystis carinii respectively, the latter diagnosed by lung biopsy. Two patients with acute Brucella melitensis infections developed pneumonia. In 34 patients (30.4%) the causative organism was not identified. Most of the epidemiological and aetiological factors studied in this survey are inconsistent with previous reports on pneumonia from western countries. For example, the commonest age group affected was younger than in western series. Tuberculous and brucella pneumonia, not commonly seen in western countries, are diagnoses to be considered in Saudi Arabia.