SARS: pharmacotherapy

The pharmacotherapy for severe acute respiratory syndrome (SARS) is controversial and largely anecdotal. Most patients with suspected SARS should initially be treated with potent antibiotics before proceeding to 'anti-SARS' therapy. There is a spectrum of severity and rate of progression in SARS, and the stages of viral replication, inflammatory pneumonitis and residual pulmonary fibrosis are clinically non-distinct. Although now considered lacking in efficacy, ribavirin was used extensively in Hong Kong for treatment of SARS. Retrospective data suggest that the use of Kaletra (ritonavir and lopinavir), an anti-protease, could reduce mortality and improve outcomes, although the adverse reactions are also worrisome. Anecdotal experience strongly supports the use of steroid, at least in a subset of SARS patients, particularly with 'critical SARS' who display continued clinical instability or deterioration and progressive radiographic or HRCT deterioration. A retrospective study carried out of 72 probable SARS patients has shown that cases who received pulse methylprendisolone did not differ in cumulative steroid dosage or adverse reactions, although the former patients had less oxygen requirement, better radiographic outcome, and less likelihood of requiring rescue pulse steroid therapy than their counterparts. Nevertheless, lower dosage of steroid as initial therapy in SARS had also been associated with good clinical outcomes. Poor responders to initial therapy might benefit from rescue steroid therapy or intravenous Pentaglobin. Other drug treatments had also been tried in desperate patients, including the use of convalescence serum and plasmapheresis. Secondary infections could be troublesome, particular for patients with prolonged hospitalization and mechanical ventilation.