IMPAIRMENT OF FINGERTIP VASOMOTOR REFLEXES IN LEPROSY PATIENTS AND APPARENTLY HEALTHY CONTACTS

Fingertip blood-flow velocity and its control by vasomotor reflexes we re studied in leprosy patients and in healthy controls with a laser Do ppler flowmeter. In newly registered patients, the flow was significan tly lower than in the healthy controls, and even lower values were rec orded in the longstanding patients with lower limb ulcers and/or defor mity. The newly registered patients showed substantially impaired vaso motor reflex responses in the fingertips to cold challenge of the oppo site hand or deep inspiratory gasp. Low blood flow and impairment of v asomotor reflexes were more prominent in those leprosy patients who sh owed clinical evidence of neuropathy and/or histological evidence of r eaction in a punch biopsy of leprosy skin lesions. This aspect of dysa utonomia to cold challenge was particularly prominent in apparently he althy, fully treated ex-patients. There was an unexpectedly high preva lence of impairment of vasomotor reflexes in newly registered and appa rently healthy, adequately treated leprosy patients. The method is ver y sensitive, and it remains to be established whether the lesions it d etects are nonprogressive residues, or previous nerve damage, or an in dication of on-going nerve damage. A minority of leprosy contacts show ed impairment of vasomotor reflexes. Those with two or more affected f ingers were more likely to have had a higher level of exposure to Myco bacterium leprae than those with one or no affected fingers. The cause of this unexpected impairment of fingertip vasomotor reflexes in a mi nority of leprosy control workers has not yet been determined.