Epidemics of vascular toxicity and pulmonary hypertension: what can be learned?

Epidemics of vascular disease caused by toxins and infectious agents affecting both humans and animals have been common in history. Examples of agents implicated include anorexients, ergotamine, mercury, arsenic, vinyl chloride, thorotrast, plant alkaloids, nitrites, toxic oil, tryptophan and bacterial, viral and parasitic infections. A major characteristic of these disorders is endothelial dysfunction, which may manifest itself in vasospastic disorders, sclerodermiform skin lesions, fibrosis, osteolytic lesions, polyneuropathy and portal and pulmonary hypertension. Angiosarcoma may also be a late outcome. These diseases are more common than is generally appreciated. The aetiology is usually multifactorial. This and other factors contribute to delayed recognition.