Review Question - QID 217215

This patient who presents with low-grade fevers, a peripheral red lesion, and unilateral periorbital swelling most likely has Chagas disease. If left untreated, this disease can cause dilated cardiomyopathy.

Chagas disease is caused by infection with the protozoa Trypanosoma cruzi. This disease is transmitted by the triatomine, a type of reduviid bug (“kissing bug”) whose painless bite deposits infected feces into the host. The disease is most commonly seen in rural South America with poor sanitation, tropical environments, and immunosuppression being major risk factors. Acutely, Chagas disease presents with a painless red lesion at the site of entry, low-grade fevers, and the Romaña sign, which is unilateral periorbital swelling. If left untreated, chronic infection can result in dilated cardiomyopathy, megacolon, and megaesophagus. Treatment is with the anti-trypanosomal agents benznidazole or nifurtimox.

Pino-Marin et al. review the pathophysiology underlying chronic consequences of Chagas disease. They discuss how cardiac dysautonomia, parasite-mediated myocardial damage, and chronic immune-mediated injury are key factors in the development of dilated cardiomyopathy in these patients.

Figure/Illustration A is a clinical photograph of a patient with Chagas disease. The unilateral periorbital swelling observed (red circle) is a classic manifestation of the disease known as the Romaña sign.

Incorrect Answers:
Answer 1: Anemia is a chronic manifestation of malaria infection; however, this disease characteristically presents with cyclic high spiking fevers every 3-4 days. It may also be seen in Chagas disease but is less common in this disease.

Answer 3: Encephalopathy is a chronic manifestation of Trypanosoma brucei (African sleeping sickness) infection. The acute manifestations of this disease are a rash 1-2 months after initial contact, diffuse facial edema, and low-grade fevers.

Answer 4: Hepatosplenomegaly is a chronic manifestation of Leishmania donovani infection. The acute manifestations of this disease are high spiking fevers, abdominal pain, and weight loss. It may also be seen in Chagas disease but is less common in this disease.

Answer 5: Meningitis is a chronic manifestation of Naegleria fowleri infection, which occurs after exposure to freshwater containing the amoeba. The acute manifestations of this disease are nose bleed, loss of smell, severe headache, and photophobia.

Bullet Summary:
Chronic infection with Trypanosoma cruzi (Chagas disease) can result in dilated cardiomyopathy, megaesophagus, and megacolon.