Severe Acute Respiratory Syndrome (SARS): A Brief Review With Exploration of the Outcomes, Prognostic Factors and Sequelae

Severe Acute Respiratory Syndromes (SARS) is a novel infectious disease with significant morbidity and mortality. While heated debates and vigorous scientific investigations are still ongoing over the treatment, prevention and infection control of this deadly disease, substantial data has been accumulated concerning the outcomes and prognostic factors. Postmortem findings of the deceased have revealed diffuse alveolar damage, together with evidence of fibrosis and organization. A number of predicting indicators such as advanced age, presence of co-morbidities, extensive radiological involvement, high coronaviral load and elevated serum lactate dehydrogenase have been identified to be independent predictors for adverse clinical outcomes such as admission to intensive care unit, mechanical ventilation, and death. A number of recovered SARS patients experienced exertional breathlessness, malaise, asthenia during the early recovery phase, while restriction and isolated reduction in diffusion capacity were the commonest lung function abnormalities identified during the subsequent follow-up visits. Radiological abnormalities including residual groundglass appearance and fibrosis were still detectable in these patients from their high-resolution computed tomography after recovery. Some recovered SARS patients were found to be suffering from psychological problems and avascular necrosis of the large joints.