A longitudinal study over six years was undertaken of 494 residents of the municipality of Mambaí, Goiás. Two hundred and twelve (43%) were seropositive in 1975/76 and 199 of 464 of the same patients group, positive in 1980/82 (42.8%). At both examination single radiographs of the oesophagus were obtained immediately after ingestion of 75ml of barium sulphate solution and a second X-ray taken one minute later. Among the 201 seropositive patients without megaesophagus in the first study 4 (2%) evolved megaesophagus during the six years of observation. During this time, using Rezende's classification, patients with established megaesophagus, changed their group in the following manner. Only one Group I patient changed to group II. Only one group II patient progressed to group IV. Progress of megaesophagus in the affected patients ocurred in 2.8% of 212 patients. Also four patients with grade I megaesophagus initially had a normal oesophagogram on the follow up examination. Ten patients had doubtful oesophagogram initially and six on follow up, 75% of these patients were seropositive. This study could indicate that a doubtful oesophagogram is an early sign of megaoesphagus.
Longitudinal study of development of megaoesophagus; Chagas' disease; Barium swallow technique; Chagasic megaoesophagus