# Diagnostic methods for protozoan diseases: a review focused on leishmaniasis, Chagas disease and malaria **Authors:** Ada da Silva Matos, Rodrigo Nunes Rodrigues-da-Silva, Thais Stelzer Toledo, Laura Sant'Anna Ataides, Natália Debize da Motta, Cinthia Magalhães Rodolphi, Isabela Ferreira Soares, Francini Neves Ribeiro, Ana Luiza Carneiro Alencar, Fernanda de Moraes Maia, Josué da Costa Lima-Junior, Fernanda Nazaré Morgado PMC · DOI: 10.3389/fmicb.2026.1735371 · Frontiers in Microbiology · 2026-02-23 ## TL;DR This paper reviews diagnostic methods for three protozoan diseases—malaria, leishmaniasis, and Chagas disease—with a focus on Brazil's public health challenges and the importance of accurate diagnosis. ## Contribution The paper provides a comprehensive review of immunological and molecular diagnostic tools for protozoan diseases in the context of Brazil's epidemiology and social vulnerability. ## Key findings - Protozoan diseases like malaria, leishmaniasis, and Chagas disease are highly prevalent in Brazil due to ecological and socioeconomic factors. - Integration of clinical, epidemiological, and diagnostic data is crucial for early detection and control of these diseases in endemic areas. ## Abstract Protozoan diseases remain a serious public health challenge, particularly in countries such as Brazil, whose continental dimensions and diverse ecological settings allow for multiple transmission cycles, involving a wide range of vectors, reservoirs, intermediate and definitive hosts, suitable habitats, and a complex socioeconomic context that increases exposure to various diseases due to social vulnerability. Consequently, diseases such as malaria, leishmaniasis, and Chagas disease are highly prevalent in Brazil, affecting a significant portion of the population, especially in regions marked by greater social inequality. In this context, this study aims to present the epidemiological landscape of these diseases and discuss the role of immunological and molecular diagnostic tools, as well as the fundamental concepts that are essential for evaluating these diagnostic approaches. Overall, this review provides a detailed summary of established diagnostic approaches of these diseases and emphasizes the integration of clinical and epidemiological information with the application of sensitive and specific diagnostic techniques aimed at promoting early detection, monitoring, and control of infections in endemic areas, highlighting the important role of diagnosis as a strategic tool in public health. ## Linked entities - **Diseases:** malaria (MONDO:0005136), leishmaniasis (MONDO:0011989), Chagas disease (MONDO:0001444) ## Full-text entities - **Genes:** HSPA4 (heat shock protein family A (Hsp70) member 4) [NCBI Gene 3308] {aka APG-2, HEL-S-5a, HS24/P52, HSPH2, RY, hsp70}, HDGFL2 (HDGF like 2) [NCBI Gene 84717] {aka HDGF-2, HDGF2, HDGFRP2, HRP-2, HRP2}, IFNG (interferon gamma) [NCBI Gene 3458] {aka IFG, IFI, IMD69}, DNAJC5 (DnaJ heat shock protein family (Hsp40) member C5) [NCBI Gene 80331] {aka CLN4, CLN4B, CSP, DNAJC5A, mir-941-2, mir-941-3}, DSPP (dentin sialophosphoprotein) [NCBI Gene 1834] {aka DFNA39, DGI1, DMP3, DPP, DSP}, IL2 (interleukin 2) [NCBI Gene 3558] {aka IL-2, TCGF, lymphokine}, HDGFL3 (HDGF like 3) [NCBI Gene 50810] {aka CGI-142, HDGF-2, HDGF2, HDGFRP3, HRP-3}, REG3A (regenerating family member 3 alpha) [NCBI Gene 5068] {aka HIP, HIP/PAP, INGAP, PAP, PAP-H, PAP1}, ALB (albumin) [NCBI Gene 280717] - **Diseases:** hypotension (MESH:D007022), genetic disorders (MESH:D030342), convulsions (MESH:D012640), NTD (MESH:D009436), fever (MESH:D005334), CVL (MESH:D007898), vomiting (MESH:D014839), Protozoan diseases (MESH:D011528), P. vivax malaria (MESH:D016780), LV (MESH:D018487), leukopenia (MESH:D007970), arrhythmias (MESH:D001145), autoimmune conditions (MESH:D001327), nausea (MESH:D009325), hemorrhages (MESH:D006470), fatigue (MESH:D005221), NTDs (MESH:D058069), hepatosplenomegaly (MESH:C535727), dyspnea (MESH:D004417), weakness (MESH:D018908), Leishmania infection (MESH:D007896), swelling (MESH:D004487), headache (MESH:D006261), mucocutaneous leishmaniasis (MESH:D007897), physical disability (MESH:D059445), Malaria (MESH:D008288), HIV (MESH:D015658), American trypanosomiasis (MESH:D014355), cutaneous leishmaniasis (MESH:D016773), chronic (MESH:D002908), Infectious diseases (MESH:D003141), heart failure (MESH:D006333), hypersensitivity (MESH:D004342), loss of appetite (MESH:D001068), parasitic diseases (MESH:D010272), congenital infections (MESH:D007239), cardiovascular condition (MESH:D002318), thrombocytopenia (MESH:D013921), neurological, dermatological, and gastrointestinal alterations (MESH:D005767), chills (MESH:D023341), parasitemia (MESH:D018512), toxicity (MESH:D064420), pLDH (MESH:C538133), weight loss (MESH:D015431), tropical diseases (MESH:D015493), ulcers (MESH:D014456), hyperventilation (MESH:D006985), anemia (MESH:D000740), protozoal infections (MESH:D020808), altered consciousness (MESH:D003244), deaths (MESH:D003643), CL (MESH:D002971) - **Chemicals:** sulfadoxine-pyrimethamine (MESH:C001205), artemisinin (MESH:C031327), biotin (MESH:D001710), artesunate and amodiaquine (MESH:C515299), nifurtimox (MESH:D009547), adenine (MESH:D000225), HCl (MESH:D006851), ethanol (MESH:D000431), artesunate (MESH:D000077332), Matrix-M (MESH:C000625666), paromomycin (MESH:D010303), cytosine (MESH:D003596), phenol (MESH:D019800), water (MESH:D014867), Farnesol (MESH:D005204), essential oils (MESH:D009822), lumefantrine (MESH:D000078102), Glucantime (MESH:D000077485), 3,3',5,5'-tetramethylbenzidine (MESH:C021758), C (MESH:D002244), guanine (MESH:D006147), Pentostam (MESH:D000967), musk (MESH:C008563), thymine (MESH:D013941), MgCl2 (MESH:D015636), paraffin (MESH:D010232), T (MESH:D014316), artemether (MESH:D000077549), gold (MESH:D006046), acid (MESH:D000143), allopurinol (MESH:D000493), pyronaridine (MESH:C027871), Tween 20 (MESH:D011136), alcohol (MESH:D000438), PVDF (MESH:C024865), DAB (MESH:C000469), A (MESH:D001151), formaldehyde (MESH:D005557), benzamide (MESH:C037689), H2SO4 (MESH:C033158), saponin (MESH:D012503), Benznidazole (MESH:C009999), amiodarone (MESH:D000638), CO2 (MESH:D002245), polystyrene (MESH:D011137), SYBR Green (MESH:C098022), cipargamin (MESH:C552304), aluminum hydroxide (MESH:D000536), chloroform (MESH:D002725), primaquine (MESH:D011319), sesquiterpene (MESH:D012717), ganaplacide (MESH:C000599914), ALP (MESH:C001864), amphotericin B (MESH:D000666), ergosterol (MESH:D004875), miltefosine (MESH:C039128), OPD (MESH:C034193), tafenoquine (MESH:C055852), balsam (MESH:D001453), 2,4,5-trisubstituted benzamides (-) - **Species:** Leishmania shawi (species) [taxon 5680], Leishmania lainsoni (species) [taxon 5677], Human immunodeficiency virus 1 (no rank) [taxon 11676], Trypanosoma cruzi (species) [taxon 5693], Thermus aquaticus (species) [taxon 271], Mus musculus (house mouse, species) [taxon 10090], Leishmania guyanensis (species) [taxon 5670], Canis lupus familiaris (dog, subspecies) [taxon 9615], Leishmania infantum (species) [taxon 5671], Leishmania amazonensis (species) [taxon 5659], Anopheles (series) [taxon 44484], Leishmania lindenbergi (species) [taxon 651832], Plasmodium vivax (malaria parasite P. vivax, species) [taxon 5855], Leishmania mexicana (species) [taxon 5665], Leishmania naiffi (species) [taxon 5678], Plasmodium falciparum (malaria parasite P. falciparum, species) [taxon 5833], Homo sapiens (human, species) [taxon 9606], Lutzomyia longipalpis (species) [taxon 7200], Pf [taxon 1985359], Leishmania braziliensis (species) [taxon 5660], Plasmodium malariae (species) [taxon 5858] - **Mutations:** C -72 C, C -95 C ## Full text _Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/PMC12967969/full.md ## Figures 7 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12967969/full.md ## References 203 references — full list in the complete paper: https://tomesphere.com/paper/PMC12967969/full.md --- Source: https://tomesphere.com/paper/PMC12967969