Timely request
Tomás Agustín Orduna
Physician specialized in Tropical Medicine and Infectious Diseases
Muñiz Hospital- Mundo Sano Foundation
About two decades ago, a young woman of about 23 years of age came to my office. She had tested positive for Chagas disease by two different techniques. Diagnosis was the result of a timely request for laboratory tests indicated by a colleague, a gynaecologist, within the frame of pre-natal evaluation.
The patient was certainly “confused”, since she found no reasons for being infected. That is, in the social imaginary, this possibility is only related to living or having lived in poor dwellings with presence of vincuchas. That was not the case of my patient, who belonged to the upper-middle class of Buenos Aires city. She also discarded other possibilities related to trips or accommodation at “risky” sites; she had also not received blood transfusions that may justify the infection. Regarding her mother, at least according to the data that we had the possibility to know during that consultation, she had not lived in rural areas nor had she been exposed to other “known” risks, since, as her daughter, she had also been born and lived in that city.
Given the patient’s emotional distress of knowing that she was infected, and thinking of the possibility of having a baby, her great fear was related to the possibility of transmitting the infection to her child. Likewise, she also thought of what would happen to her, if she would progress to a heart disease, which she was told might happen.
To clear up some of her doubts, initially I tried to calm her down and mentioned the options we had for her follow-up. First, and in relation to a possible vertical transmission, I told her that it occurred on average in 10% of the infected women, but that the implementation of the diagnosis methods to the child at birth and during follow-up, the detection of parasite presence and the possible further treatment ensured a 100% cure. This information relieved her.
As a response to the question about her chances to become infected, I mentioned what is known, about 30% of the patients. After this answer, we addressed the option of treatment with antiparasitic drugs, since she was very young and it might be an opportunity to stop or prevent progression to a heart disease. On the other hand, although our guidelines about management of people infected with Trypanosoma cruzi still did not include formal recommendations about this, I mentioned works showing that treatment of infected women might be a primary prevention method of vertical Chagas, since the absence of transmission in previously treated women compared with untreated ones was already evident.
In other words, treating her might be a great benefit to her and might prevent infection of her future child. At this point of the consultation, I noticed that she was better, less tense and distressed, and hopeful regarding the proposals offered. However, we still had to find out how she had become infected. Hence, I mentioned the need to evaluate her mother. She agreed to make the proposal to her mother and I ordered the corresponding tests.
Some weeks later, the patient came to the office with her mother and brought the requested pre-treatment tests. Her mother was very worried because her serological tests were also positive. I would say that I expected that result due to the lack of another epidemiological factor in my patient. Again, I explained the controls and tests that were necessary for her evaluation, she asked about options of a specific treatment, I answered with data of the available evidence, considering her age (55 years). Therefore, I suggested that we should focus on knowing if she had any health effects of infection and emphasized the need for regular follow-up.
During the elaboration of the medical history, we learned that her mother, i.e., the initial patient’s grandmother, was born in a rural area in Jujuy and lived there until her young adulthood. There was the fact, the necessary link between vectors and my patient... vertical transmission over two generations! I was relieved, because a point that intrigued me was clarified. The grandmother, almost 80 years old, was fine, had no heart disease of any kind –at least not confirmed in the regular health controls. After some time, the granddaughter confirmed that her grandmother was positive.
This experience, which I had in the “office of regional pathologies”, was a very good example of the need to explore the different epidemiological possibilities to find the exposure to the risk of infection with T. cruzi.
As a summary of what I think is relevant, I mention again the timely request for serological tests by a gynaecologist, a colleague whom I did not get to know, but who undoubtedly was very well trained and aware of our main endemic disease and the need to screen for Chagas disease in prenatal tests. Likewise, this “family cohort” clearly shows what we have been observing and supporting in our teaching activities: today Chagas disease should be considered all throughout the country and in urban areas within and outside the endemic provinces, due to internal migrations from rural areas with a history of houses infested with vinchucas. We should not forget other possible transmission routes: vertical, as in this case, or transfusions received before the approval of the Law of safe blood.
Finally, I would like to stress the need to think of the relationship between Chagas disease and the mother-child pair, since screening and specific treatment of infected pre-fertile and fertile women is a primary tool for the prevention of vertical Chagas disease. Let us do all that is necessary to apply the acquired knowledge and the supporting evidence. It is our duty as members of the health team!