SARS – the first comprehensive description of the damage caused by the virus

Research News in the Journal of Pathology

Doctors working near to the first outbreak of severe acute respiratory syndrome (SARS) Guangdong, China, have just published the first histopathological description of the effects of this viral infection in the Journal of Pathology.

Basing their findings on autopsies of three people who died of SARS, Dr Yanqing Ding and his colleagues showed the virus causes extensive disruption throughout the body.

The main pathological changes were in the lungs:

• All three victims had extensive pulmonary consolidation, significant pulmonary oedema, as well as localised haemorrhage and necrosis. There was also widespread hyaline membrane formation, local inflammation and damage to the cells lining the airways.

In addition:

• The researchers found massive necrosis within the spleen and local necrosis in lymph glands.
• There was systemic vasculitis, involving apoptosis of endothelial cells, infiltration of monocytes. Lymphocytes and plasma cells were also found in vascular walls within the heart, lung, liver, kidney, adrenal gland and striated muscle.
• Electron microscopy revealed clusters of viruses in lung tissue, and provides more evidence that the causal agent is a coronavirus.

“These findings help us understand the nature of this disease,” says Dr Ding.

The patients had all died in February 2003, and their first symptoms of the disease were extreme fevers and chills with generalised aching pains. Two had had unproductive coughs, while one produced mildly blood-stained sputum. Before they died they had dyspnoea and X-ray images had revealed shadows on the lungs. The patients showed no sign of illness before this infection.