Previous work has shown that plasma and tissue concentrations of histamine are elevated in rats with experimental diabetes mellitus and that leucocytes and platelets from patients with peripheral vascular disease have a higher histamine content than those from controls. The lens is a small clear structure that focuses light as it enters the eye. We undertook morphometric assessment of endoneurial microvessels in the sural nerves, taken from severely ischaemic amputated legs in nine chronic non-diabetic PVD. A total of 1030 patients treated for ABSSSI were evaluable; 527 (51%) had DM and/or PVD; 471 (46%) had DM alone; and 178 (17%) had PVD alone. If demonstrated in appropriate clinical studies including randomized trials, it would provide an interesting approach to prevent advanced and blinding stages of diabetic retinopathy, particularly in areas where access to care is limited. In a smaller study, it was established that NIDDM and PVD patients have significantly (P < 0·002) greater plasma 5-HT concentrations than controls. Out of 556 patients with a history of foot ulcer 123 (22.1%) underwent amputation. In univariate analysis, PVD was associated with an increased level of systolic blood pressure (SBP), BUN and Cr, cigarette smoking, CI, CHD, proteinuria and retinopathy. Peripheral vascular disease is a leading cause of disability among people older than 50 years and in those with diabetes. It is frequently found in people with coronary artery disease, because atherosclerosis, which causes coronary artery disease, is a widespread disease of the arteries. However, in mild cases of PVD there may be no symptoms.