Clinical features and epidemiology of melioidosis pneumonia: results from a 21-year study and review of the literature.

BACKGROUND: Melioidosis is an important cause of community-acquired sepsis in Southeast Asia and northern Australia, and pneumonia is the most common presentation. Clinical manifestations range from acute fulminant sepsis to chronic infection mimicking tuberculosis. Pneumonia may be the primary presenting feature, or it can develop secondary to initial disease at a distant focus.
METHODS: A prospective database of all melioidosis patients at Royal Darwin Hospital (Australia) between 1989 and 2010 was reviewed.
RESULTS: Of 624 patients with culture-confirmed melioidosis, 319 (51%) presented with pneumonia as the primary diagnosis. Acute/subacute presentations accounted for the majority of primary pneumonia cases (91%); chronic disease was seen less commonly (9%). Secondary pneumonia developed in 20% of patients with other primary melioidosis presentations and was particularly common in those with positive blood cultures. Risk factors for presentation with primary pneumonia (compared with other primary presentations) were rheumatic heart disease or congestive cardiac failure, chronic obstructive pulmonary disease, smoking, and diabetes mellitus, with P < .05 for these conditions in a multivariate logistic regression model. Patients presenting with pneumonia more frequently developed septic shock (33% vs 10%; P < .001) and died (20% vs 8%; P <.001) compared with patients with other primary presentations. Multilobar disease occurred in 28% of primary pneumonia patients and was associated with greater mortality (32%) than in those with single-lobe disease (14%; P < .001).
CONCLUSIONS: Melioidosis pneumonia is often a rapidly progressive illness with high mortality, particularly among those with multilobar disease. Risk factors have been identified, and early diagnosis and treatment should be priorities.