Clinical<FONT FACE=Symbol>¾</FONT>neurological and electroneuromyographic evaluation of the indeterminate chronic form of Chagas disease

Abstract

EUSTÁQUIO CLARET DOS SANTOS** Objective-To evaluate if alterations exist in patients with the indeterminate chronic form of Chagas disease, through a clinical-neurological and electroneuromyographic study. Method-From March 1996 to April 1999, 49 patients with the indeterminate chronic form of Chagas disease sent to me by the "Chagas Disease OutPatient Reference Centre" of the Clinical Hospital of the Federal University of Minas Gerais (UFMG) were submitted to the clinicalneurological and electroneuromyographic study. Seventysix healthy volunteers, who had no Chagas disease, were examined and some of the reference values for the electroneuromyographic study were thus obtained. The electroneuromyographic study consisted of sensory and motor conduction of nerves of superior and inferior members; late response study ("F" wave and "H" reflex) of tibial posterior nerve; electromyography strictly defined; and computed motor unit counting. Results-Considering the anthropometric characteristics of the two groups (sex, color, age and height) no differences were found that could influence the results. The exam of muscular force and sensibility (superficial and deep) of the Chagas disease patients was normal. There were reflex alterations in significant number in Chagas disease patients (83.7% for the radial; 81/6% for the triceps; 72.4% for the biceps; 49% for the ankle; 38.8% for the patellar). The electroneuromyographic study including the motor unit counting was normal in 13 of the 49 Chagas disease patients (26/5%). The great majority of the Chagas disease patients presented a normal study result of sensitive and motor conduction (71.4%). The carpal tunnel syndrome was observed in nine patients with the indeterminate chronic form (18.4%). In everybody there was a decrease of the speed of sensitive conduction of the median nerve. An increase of distal motor latency was present in five patients (10.2%). Other conduction alterations found were: a decrease of the speed of sensitive conduction of the ulnar nerve in one case (2.0%); decrease of the speed of motor conduction of the fibular nerve in one case (2.0%); reduction of the width of the potential motor of the right ulnar nerve in one case (2.0%);