Radiographic Findings in 20 Patients with Hantavirus Pulmonary Syndrome Correlated with Clinical Outcome

Hantavirus is a rare rodent-borne pathogen responsible for the Hantavirus pulmonary syndrome. The objective of this study was to review the clinical and radiographic findings of patients presenting with Hantavirus pulmonary syndrome in northern Alberta, Canada. We retrospectively reviewed the cases of 20 patients who presented with Hantavirus pulmonary syndrome from 1989 to 1999. Two patterns of presentation were identified. One group (13/20 patients) presented with fulminant clinical and radiographic findings and required intensive care support. Six (46%) of the 13 died within a few days of presentation. Some presented in respiratory failure with bilateral parenchymal infiltrates or a rapid progression from mild bilateral interstitial changes to bilateral interstitial and alveolar infiltrates with pleural effusions. The radiographic findings paralleled these clinical symptoms. The second group (7/20) consisted of patients whose clinical course was more limited, as were their corresponding radiographic findings. These patients had a limited hospital stay, and only minimal changes were identified on radiographs. None of the second group of patients died. Clearly, in our study, the patients with Hantavirus pulmonary syndrome presented as two groups: those with the fulminant form of the illness and those with the limited type. Of the patients we studied, the group with the fulminant form presented with severe clinical symptoms and radiographic signs of pulmonary disease and had a 46% mortality rate. The group with the limited form presented with mild clinical symptoms and minimal radiographic changes and had no mortalities.