How Do Immunosuppressants Affect Chagas Disease?
At a Glance
Taking immunosuppressants or biologics can cause dormant Chagas disease to reactivate and multiply, leading to severe complications. To safely take these medications, you must be closely monitored with regular qPCR blood tests and may need preemptive antiparasitic drugs like benznidazole.
In this answer
3 sections
If you have chronic Chagas disease and need to start an immunosuppressive drug—such as a biologic, TNF-alpha inhibitor, high-dose corticosteroid, or chemotherapy—you are at a significant risk for Chagas disease reactivation [1][2][3]. While it is not necessarily dangerous to take these medications, doing so requires strict medical supervision. Suppressing your immune system allows the dormant Trypanosoma cruzi parasite to multiply, which can trigger a severe flare-up of the disease [1][3].
Understanding Chagas Disease Reactivation
During the chronic phase of Chagas disease, your immune system keeps the parasite in check, preventing it from multiplying rapidly. When you take medications that suppress your immune system (like rituximab, TNF-alpha inhibitors, or drugs used for cancer and organ transplants), this defense is weakened [4][5][6].
If the parasite begins to multiply rapidly, it causes reactivation. This can lead to severe, potentially life-threatening complications, including dangerous inflammation in the brain and spinal cord (meningoencephalitis), heart issues, or skin lesions [7][8][9]. Reactivation acts much like a severe form of the initial, acute phase of the infection.
Symptoms to Watch For
If you are on immunosuppressive medication, you must watch your body closely. Contact your doctor immediately if you develop symptoms that could indicate reactivation, such as:
- Persistent fever
- Severe headaches or confusion (signs of brain inflammation)
- Unexplained skin rashes, bumps, or lesions
- New or worsening chest pain and shortness of breath
- Seizures
How Your Care Team Will Protect You
To safely undergo immunosuppressive therapy, your doctors must proactively monitor and manage your Chagas disease.
1. Specialized Monitoring (qPCR Testing)
Standard blood tests for Chagas disease look for antibodies. Because you already have antibodies from your chronic infection, standard blood tests cannot tell if the parasite has suddenly started multiplying again. Furthermore, severe immunosuppression can sometimes make antibody levels falsely low [2][10].
Instead, your doctors must use a test called quantitative PCR (qPCR) or examine your blood directly under a microscope [11][2]. The qPCR test looks directly for the DNA of the parasite in your blood. Monitoring via qPCR is mandatory before you start your new medication, regularly during your treatment, and for a period after your treatment ends [12][5][4]. While exact timelines vary based on your specific medications, “regularly” often means weekly or monthly blood tests, especially in the early stages of immunosuppression [13][14][5]. This allows your care team to detect if the parasite is multiplying before you develop severe symptoms [15][11].
2. Preemptive Treatment
If your routine qPCR tests show a rising level of the parasite in your blood (called parasitemia), your doctors will likely start you on antiparasitic medication immediately [15][10][16]. This is called preemptive treatment.
The most common medication used is benznidazole [17][18]. Taking this medication can successfully reduce the parasite levels and prevent a severe clinical flare-up [16][19]. (Note that benznidazole can cause side effects like skin rashes or nerve tingling, which your care team will monitor). In some complex cases, such as those with central nervous system involvement, longer treatment courses or secondary maintenance therapies may be required [20].
Next Steps
Because guidelines for exactly how often to test can vary between institutions, it is critical that your prescribing doctor (such as a rheumatologist or oncologist) works closely with an infectious disease specialist who understands Chagas disease [21]. Together, they can create a safe, customized monitoring and treatment plan for your specific medication regimen.
Common questions in this guide
Why is it risky to take immunosuppressants if I have Chagas disease?
What are the signs of Chagas disease reactivation?
How will my doctors monitor my Chagas disease during treatment?
What happens if my qPCR test shows the Chagas parasite is multiplying?
Which doctors should manage my care if I need an immunosuppressant?
Questions to Ask Your Doctor
Curated prompts to bring to your next appointment.
- 1.Who will be responsible for ordering and interpreting my regular qPCR tests during my immunosuppressive therapy?
- 2.What is the exact schedule for my blood testing before, during, and after my treatment?
- 3.Do you have an infectious disease specialist with experience in Chagas disease on the team to co-manage my care?
- 4.What specific early symptoms of reactivation should I watch out for at home, and who should I call if I experience them?
- 5.If my qPCR test shows a rising parasite count, what is our immediate plan for preemptive treatment?
Questions For You
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References
References (21)
- 1
Chagas Disease in People with HIV: A Narrative Review.
Clark EH, Bern C
Tropical medicine and infectious disease 2021; (6(4)) doi:10.3390/tropicalmed6040198.
PMID: 34842854 - 2
Clinical and epidemiological features of chronic Trypanosoma cruzi infection in patients with HIV/AIDS in Buenos Aires, Argentina.
Benchetrit AG, Fernández M, Bava AJ, et al.
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases 2018; (67()):118-121 doi:10.1016/j.ijid.2017.11.027.
PMID: 29196277 - 3
New insights into Trypanosoma cruzi genetic diversity, and its influence on parasite biology and clinical outcomes.
Silvestrini MMA, Alessio GD, Frias BED, et al.
Frontiers in immunology 2024; (15()):1342431 doi:10.3389/fimmu.2024.1342431.
PMID: 38655255 - 4
Chagas disease reactivation in rheumatologic patients: association with immunosuppressive therapy and humoral response.
Ringer A, Ruffino JP, Leiva R, et al.
Clinical rheumatology 2021; (40(7)):2955-2963 doi:10.1007/s10067-021-05581-2.
PMID: 33438080 - 5
Chagas disease in the immunocompromised host.
Clark EH, Bern C
Current opinion in infectious diseases 2024; (37(5)):333-341 doi:10.1097/QCO.0000000000001035.
PMID: 38963802 - 6
Case report of Chagas disease reactivation: new diagnosis tool by direct microscopic observation of biopsy specimen and its preservation fluid.
Lopez-Albizu C, Bravo MP, Pico M, Fernandez ML
Revista da Sociedade Brasileira de Medicina Tropical 2020; (54()):e20200326 doi:10.1590/0037-8682-0326-2020.
PMID: 33338120 - 7
Epidemiological-clinical profile and mortality in patients coinfected with Trypanosoma cruzi/HIV: experience from a Brazilian reference center.
Hasslocher-Moreno AM, Sousa AS, Xavier SS, et al.
Revista da Sociedade Brasileira de Medicina Tropical 2022; (55()):e02402022 doi:10.1590/0037-8682-0240-2022.
PMID: 36287507 - 8
Cerebral Trypanosomiasis in an Immunocompromised Patient: Case Report and Review of the Literature.
Kaushal M, Shabani S, Cochran EJ, et al.
World neurosurgery 2019; (129()):225-231 doi:10.1016/j.wneu.2019.05.260.
PMID: 31176839 - 9
Reactivation of Chagas disease in organ transplant recipients: Panniculitis as the only skin manifestation in a three case series.
Souza BCE, Ang PL, Cerulli FG, et al.
The Australasian journal of dermatology 2021; (62(2)):231-232 doi:10.1111/ajd.13478.
PMID: 32981047 - 10
Reactivation of Chagas Disease in a Patient With Follicular Lymphoma Diagnosed by Means of Quantitative Real-Time Polymerase Chain Reaction.
Garzón MI, Sánchez AG, Goy MC, et al.
Open forum infectious diseases 2015; (2(2)):ofv060 doi:10.1093/ofid/ofv060.
PMID: 26180822 - 11
Multiple myeloma and Chagas disease: qPCR as a marker for preemptive antiparasitic therapy: a case reports series and review.
Carvalho NB, Freitas VLT, Seguro FS, et al.
Revista do Instituto de Medicina Tropical de Sao Paulo 2024; (66()):e10 doi:10.1590/S1678-9946202466010.
PMID: 38324876 - 12
Parasite load evaluation by qPCR and blood culture in Chagas disease and HIV co-infected patients under antiretroviral therapy.
Marcon GEB, Ferreira JJG, de Almeida EA, et al.
PLoS neglected tropical diseases 2022; (16(3)):e0010317 doi:10.1371/journal.pntd.0010317.
PMID: 35353834 - 13
Early polymerase chain reaction detection of Chagas disease reactivation in heart transplant patients.
da Costa PA, Segatto M, Durso DF, et al.
The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation 2017; (36(7)):797-805 doi:10.1016/j.healun.2017.02.018.
PMID: 28320630 - 14
Reactivation of Chagas disease among heart transplant recipients in the United States, 2012-2016.
Gray EB, La Hoz RM, Green JS, et al.
Transplant infectious disease : an official journal of the Transplantation Society 2018; (20(6)):e12996 doi:10.1111/tid.12996.
PMID: 30204269 - 15
Fulminant and fatal Trypanosoma cruzi reactivation in a patient with lymphoma.
Lukose G, Mertelsmann A, Rolon RMM, et al.
ASM case reports 2026; (1(2)) doi:10.1128/asmcr.00157-25.
PMID: 41503536 - 16
Quantitative PCR for parasitemia monitoring and preemptive therapy in patients with Chagas disease and autoimmune rheumatic disorders undergoing biologic treatment: a case series.
Carvalho NB, Freitas VLT, Aikawa NE, et al.
Revista da Sociedade Brasileira de Medicina Tropical 2025; (58()):e008022025 doi:10.1590/0037-8682-0419-2024.
PMID: 40465888 - 17
Case Report: Successful Lung Transplantation from a Donor Seropositive for Trypanosoma cruzi Infection (Chagas Disease) to a Seronegative Recipient.
Salvador F, Sánchez-Montalvá A, Sulleiro E, et al.
The American journal of tropical medicine and hygiene 2017; (97(4)):1147-1150 doi:10.4269/ajtmh.17-0156.
PMID: 28749767 - 18
American Trypanosomiasis (Chagas Disease).
Echeverria LE, Morillo CA
Infectious disease clinics of North America 2019; (33(1)):119-134 doi:10.1016/j.idc.2018.10.015.
PMID: 30712757 - 19
Prevalence of Chagas Disease among Solid Organ-Transplanted Patients in a Nonendemic Country.
Salvador F, Sánchez-Montalvá A, Sulleiro E, et al.
The American journal of tropical medicine and hygiene 2018; (98(3)):742-746 doi:10.4269/ajtmh.17-0735.
PMID: 29405102 - 20
Benznidazole in Cerebrospinal Fluid: a Case Series of Chagas Disease Meningoencephalitis in HIV-Positive Patients.
Fernández ML, Marson ME, Mastrantonio GE, et al.
Antimicrobial agents and chemotherapy 2021; (65(3)) doi:10.1128/AAC.01922-20.
PMID: 33361290 - 21
Parasitological, serological and molecular diagnosis of acute and chronic Chagas disease: from field to laboratory.
Schijman AG, Alonso-Padilla J, Longhi SA, Picado A
Memorias do Instituto Oswaldo Cruz 2022; (117()):e200444 doi:10.1590/0074-02760200444.
PMID: 35613155
This page provides educational information about managing Chagas disease while on immunosuppressive therapy. Always consult an infectious disease specialist and your prescribing doctor for a personalized monitoring and treatment plan.
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