Acute-Phase Disease
The only good opportunity for curing Chagas disease—that is, of completely eradicating the Trypanosoma cruzi (T. cruzi) parasite from the body—is if treatment can be started early in the course of the disease, during the acute phase.
There was an error. Please try again.
In any person diagnosed with acute T. cruzi infection, or if an infant is found to have a congenital infection, treatment should be given with antitrypanosomal drugs. The two drugs that have been shown to be effective against T. cruzi are benznidazole and nifurtimox. Women who are pregnant should not receive these drugs.
Benznidazole
Benznidazole usually has fewer side effects and is most often the treatment of choice. This drug must be taken for 60 days. Its most common side effect is skin rash.
Nifurtimox
Nifurtimox (which is not approved in the United States) tends to cause gastrointestinal symptoms. It can also produce insomnia, disorientation, and peripheral neuropathy. These side effects limit its usefulness. This drug has to be taken for at least 90 days.
Chronic Infection
With chronic Chagas disease, eradicating the T. cruzi parasite with antitrypanosomal therapy is much more difficult than it is during the acute phase, and may be impossible.
Still, most experts recommend treating with benznidazole or nifurtimox if the infected person with chronic Chagas disease is under age 55 or 50 and does not have advanced irreversible cardiomyopathy.
Antitrypanosomal therapy is not recommended if Chagas heart disease is already present, if severe Chagas gastrointestinal disease is present (such as megacolon), or if significant liver or kidney disease is present. In these people the chances of eradicating the T. cruzi infection is very low, and the risk of side effects is high.
Chagas Cardiac Disease
Treatment with antitrypanosomal drugs is not beneficial for established Chagas heart disease. Instead, treatment should be specifically aimed at managing the heart disease itself.
Chagas heart disease is a form of dilated cardiomyopathy that often produces heart failure, and people with this disease ought to receive all the standard treatments for dilated cardiomyopathy.
Treating Heart Failure
Medical therapy usually includes treatment with beta blockers, ACE inhibitors, and spironolactone. Diuretic therapy is used to help reduce edema and dyspnea.
Cardiac resynchronization therapy (CRT) appears to be as useful in Chagas heart disease as in any other form of heart failure. However, the usefulness of CRT in treating heart failure is largely limited to people who have left bundle branch block, whether they have Chagas disease or any other form of dilated cardiomyopathy. And, unfortunately, in Chagas disease right bundle branch block is more common than left bundle branch block—so CRT is suitable for fewer people with Chagas heart failure than with other kinds of heart failure.
One concern in performing transplant surgery in Chagas heart disease has been that the immunosuppressive therapy required after transplantation may cause the T. cruzi infection to reactivate. However, clinical studies have shown that reactivation of the infection after transplantation does not appear to be a common problem in Chagas heart disease.
The risk of thromboembolism (a condition that often produces deep venous thrombosis, pulmonary embolism, or stroke ) is increased in anyone with heart failure, but it appears to be a particular risk for people with Chagas heart disease. Most people with Chagas heart disease should be placed on either anticoagulant therapy (with Coumadin or a NOAC drug), or prophylactic aspirin to lower the high risk of thromboembolism.
Treating Cardiac Arrhythmias and Preventing Sudden Death
Therapy to prevent or treat serious cardiac arrhythmias is often necessary for people with Chagas heart disease because they are at increased risk for both bradycardias (slow heart rhythms) and tachycardias (fast heart rhythms).
Bradycardias occur with some frequency in people with Chagas disease. The bradycardias are caused both by disease of the sinus node and by heart block. If the slow heart rhythm is producing symptoms, or if it appears likely to produce severe symptoms such as syncope, therapy with a pacemaker is necessary.
If cardiac function is depressed to the point that these dangerous arrhythmias are particularly likely to occur, the insertion of an implantable defibrillator should be strongly considered. However, especially in Latin America, where implantable defibrillator therapy is often not readily available, patients with Chagas disease are very likely to be treated with the antiarrhythmic drug amiodarone instead, in an attempt to reduce their risk of sudden death.
Gastrointestinal Disease
Antitrypanosomal therapy does not improve the gastrointestinal disease caused by Chagas. Treatment is aimed at reducing symptoms by decreasing gastrointestinal reflux and controlling nausea and constipation with medications and diet. Surgical intervention may become necessary if megacolon or megaesophagus are present.
Prevention
In recent decades several Latin American countries have undertaken major efforts to eradicate or at least greatly reduce Chagas disease.
Generally, these efforts have focused on getting rid of the vector of the disease—that is, the “kissing bugs” that transmit the T. cruzi parasite from human to human.
Prenatal testing for T. cruzi has helped reduce congenital transmission of the disease. Women cannot be treated with antitrypanosomal drugs while pregnant, but treatment before pregnancy is often quite effective. Women currently infected with T. cruzi are also advised not to breastfeed, although transmission of the disease through breast milk has not been proven.
