Chagas Disease

Carlos Chagas described the tropical parasitic infection caused by Trypanosoma cruzi initially in 1909, while working in a remote area collecting bugs for malaria research. The protozoan T. cruzi is endemic to Central and South America and constitutes a significant public health concern in much of South America. The life cycle of T. cruzi involves transmission to humans from the feces of an insect vector. The acute phase is characterized by fever, malaise, and generalized lymphadenopathy. In many individuals, it is not recognized as Chagas' disease during this phase. Of infected individuals, only approximately 10% to 30% progress to the chronic phase (22). Esophageal histology reveals a hypertrophic muscular layer and a significant decrease in the number of ganglion cells in Auerbach's plexus.

The dysphagia that occurs with Chagas' disease can occur anywhere from weeks to years following infection. Initially, the dysphagia is intermittent; however, as the disease progresses, it becomes persistent and more severe. Regurgitation, aspiration with pneumonia, and weight loss are common. Roberto Dantas described esophageal motor abnormalities as documented by barium esophagram or manometry in 25% of asymptomatic individuals (23). These findings typically consist of dysrhythmic contractions in early phases. As the disease progresses, the manometric findings show decreasing peristaltic amplitudes and eventually aperistalsis, which is the hallmark of this disease. Radiographically, barium swallows show a dilated atonic esophagus, similar to that seen in primary achalasia. The diagnosis can be confirmed by serology; however, false positives can occur in patients with collagen vascular disease, leishmaniasis, malaria, and syphilis (24). Treatment of the acute disease, even when recognized, is successful in eradicating the organism less than 50% of the time. Typically, benznidazole and nifurtimox are used. Treatment of the esophageal disease is similar to that of primarily achalasia, namely, pneumatic dilation and chemical (botulinum toxin) or surgical myotomy.

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