Human T-cell activation with Toxoplasma gondii antigens loaded in maltodextrin nanoparticles.

Toxoplasmosis is the most prevalent parasitic zoonosis worldwide, causing ocular and neurological diseases. No vaccine has been approved for human use. We evaluated the response of peripheral blood mononuclear cells (PBMCs) to a novel construct of Toxoplasma gondii total antigen in maltodextrin nanoparticles (NP/TE) in individuals with varying infectious statuses (uninfected, chronic asymptomatic, or ocular toxoplasmosis). We analyzed the concentration of IFN-γ after NP/TE ex vivo stimulation using ELISA and the immunophenotypes of CD4+ and CD8+ cell populations using flow cytometry. In addition, serotyping of individuals with toxoplasmosis was performed by ELISA using GRA6-derived polypeptides. Low doses of NP/TE stimulation (0.9 µg NP/0.3 µg TE) achieved IFN-γ-specific production in previously exposed human PBMCs without significant differences in the infecting serotype. Increased IFN-γ expression in CD4+ effector memory cell subsets was found in patients with ocular toxoplasmosis with NP/TE but not with TE alone. This is the first study to show how T-cell subsets respond to ex vivo stimulation with a vaccine candidate for human toxoplasmosis, providing crucial insights for future clinical trials.

Genetic Variations in the Purinergic P2X7 Receptor Are Associated with the Immune Response to Ocular Toxoplasmosis in Colombia.

Ocular toxoplasmosis (OT) is characterized by inflammation within the eye and is the most recognized clinical manifestation of toxoplasmosis. The objective of this study was to identify new single-nucleotide polymorphisms (SNPs) in the P2RX7 gene that may have significance in the immune response to OT in Colombian patients. A case-control study was conducted to investigate the associations between SNPs (rs1718119 and rs2230912) in the P2RX7 gene and OT in 64 Colombian patients with OT and 64 controls. Capillary electrophoresis was used to analyze the amplification products, and in silico algorithms were employed to predict deleterious SNPs. Stability analysis of amino acid changes indicated that both mutations could lead to decreased protein structure stability. A nonsynonymous SNP, Gln460Arg, located in the long cytoplasmic tail of the receptor, showed a significant association with OT (Bonferroni correction (BONF) = 0.029; odds ratio OR = 3.46; confidence interval CI: 1.05 to 11.39), while no significant association between rs1718119 and OT risk was observed. Based on the 3D structure analysis of the P2RX7 protein trimer, it is hypothesized that an increase in the flexibility of the cytoplasmic domain of this receptor could alter its function. This SNP could potentially serve as a biomarker for identifying Colombian patients at risk of OT.

CD8+ T-cell Exhaustion Phenotype in Human Asymptomatic and Ocular Toxoplasmosis.

This work analyzed exhaustion markers in CD8+ T-cell subpopulations in 21 samples of peripheral blood mononuclear cells (PBMCs) from individuals with ocular toxoplasmosis (n = 9), chronic asymptomatic toxoplasmosis (n = 7), and non-infected people (n = 5) by using RT-qPCR and flow cytometry techniques. The study found that gene expression of PD-1 and CD244, but not LAG-3, was higher in individuals with ocular toxoplasmosis versus individuals with asymptomatic infection or uninfected. Expression of PD1 in CD8+ central memory (CM) cells was higher in nine individuals with toxoplasmosis versus five uninfected individuals (p = .003). After ex vivo stimulation, an inverse correlation was found between the exhaustion markers and quantitative clinical characteristics (lesion size, recurrence index, and number of lesions). A total exhaustion phenotype was found in 55.5% (5/9) of individuals with ocular toxoplasmosis. Our results suggest that the CD8+ exhaustion phenotype is involved in the pathogenesis of ocular toxoplasmosis.

ROP39 is an Irgb10-specific parasite effector that modulates acute Toxoplasma gondii virulence.

Toxoplasma gondii (T. gondii) is a zoonotic apicomplexan parasite that is an important cause of clinical disability in humans. On a global scale, one third of the human population is infected with T. gondii. Mice and other small rodents are believed to be responsible for transmission of T. gondii to the domestic cat, its definitive host. Interferon-inducible Immunity-Related GTPases (IRG proteins) are important for control of murine T. gondii infections. Virulence differences between T. gondii strains are linked to polymorphic rhoptry proteins (ROPs) that cooperate to inactivate individual IRG family members. In particular, the pseudokinase ROP5 isoform B is critically important in laboratory strains of mice. We identified T. gondii ROP39 in complex with ROP5B and demonstrate its contribution to acute T. gondii virulence. ROP39 directly targets Irgb10 and inhibits homodimer formation of the GTPase leading to an overall reduction of IRG protein loading onto the parasitophorous vacuolar membrane (PVM). Maintenance of PVM integrity rescues the parasite from IRG protein-mediated clearance in vitro and in vivo. This study identifies a novel T. gondii effector that is important for specific inactivation of the IRG resistance system. Our data reveal that yet unknown T. gondii effectors can emerge from identification of direct interaction partners of ROP5B.

Detection of Giardia duodenalis and Toxoplasma gondii in soil and water samples in the Quindío River basin, Colombia.

Two zoonotic protozoan pathogens, Giardia duodenalis and Toxoplasma gondii, are important causes of waterborne infections in the Quindío region in Colombia. No previous data exist on how contamination occurs at the source for drinking water consumed by the human population in this region. Our aim was to describe the frequency of G. duodenalis and T. gondii DNA in 11 sampling points during a five-month period in water and adjacent soil at the Quindío River basin (Andean region in the central western part of Colombia). The study employed nested PCR for T. gondii, using the B1 gene as the amplification target, and single-round PCR for G. duodenalis assemblage A and assemblage B, amplifying the gdh gene, followed by DNA sequencing. In 50 soil samples, 28% (14/50) were positive for T. gondii. For G. duodenalis, distribution was in equal parts for assemblage A (8%; 4/50) and assemblage B (8%, 4/50). Genotyping of T. gondii sequences showed two soil samples with type I strain, another two samples of soil with type III strain, but most samples were of unidentified strains. In water samples, T. gondii was detected in 9.1% (5/55), G. duodenalis assemblage A in 34.5% (19/55), and G. duodenalis assemblage B in 12.7% (7/55). T. gondii DNA positivity was associated with lower soil temperature (p = 0.0239). Presence of G. duodenalis and T. gondii was evidenced in soil and water samples in the Quindío River basin, indicating soil as the potential source of contamination for the river that it is destined for human consumption. Monitoring these protozoa in drinking water is necessary to prevent public health risks in human populations.

Frequency of natural antibodies and concordance analysis for anti-TOXOPLASMA IgM tests in Colombian sera of pregnant women.

Interpretation of IgM anti-Toxoplasma can be problematic given the phenomena of "natural" IgM. We analyzed 1,503 sera obtained during prenatal care program, and we established natural and false-positive results by doing follow-up. In 101 samples the concordance between enzyme linked immunosorbent assay (ELISA) and two semi-automatized systems: electro-chemiluminescence immunoassay (ELECSYS) and vitek immunodiagnostic assay system (VIDAS) was calculated. In 1,503 serum, 71 (4,7%) had ELISA IgG negative and ELISA IgM positive results and in 44 of these had a second sample 4 weeks later. In second samples, 27 (61,3 %) were IgM and IgG negative (false positive result in the first sample) and 13 (29,5%) were ELISA IgM positive and IgG negative (natural IgM). ELISA assay had a poor concordance with enzyme-linked fluorescent immunoassay as well as ELECSYS tests, contrarily, enzyme-linked fluorescent immunoassay and ELECSYS had optimal concordance, with 100 of 101 sera obtaining the same result by both tests. We recommended to use automatized assays to measure IgM anti-Toxoplasma.

Eficacia y tolerabilidad de Nitazoxanida para parasitismo intestinal en escolares atendidos en el Centro de Salud de la Universidad del Quindío / Efficacy and tolerability of Nitazoxanide for intestinal parasitism in schoolchildren treated at the Health Center of the University of Quindío

Resumen Objetivo: Describir la efectividad del tratamiento antiparasitario intestinal brindado a niños de cuatro a nueve años atendidos en el centro de Salud de la Universidad del Quindío entre Julio de 2017 a marzo de 2018. Materiales y métodos: Estudio observacional prospectivo. Se extrajeron datos de historias clínicas de pacientes con rango de edad de 4 a 9 años, quienes consultaron en el Centro de Salud de la Universidad del Quindío y se diagnosticaron mediante coprológico con blastocistosis o giardiasis. Se seleccionaron las historias cuyo tratamiento fuese Nitazoxanida y tuviesen un coprológico control postratamiento. Se presentan estadísticas descriptivas; porcentaje de eficacia y tolerabilidad. Resultados: De 15 niños tratados con Nitazoxanida, respondieron al tratamiento 10, en quienes no se hallaron parásitos en el coprológico control. Con una eficacia del 83,3% (IC95% 60 - 100) en blastocistosis, 57,1% (IC95% 32 - 82%) en giardiasis. Conclusión: Se evidenciaron resultados porcentuales similares a los reportados en la literatura, siendo más eficaz en blastocisotisis que en giardiasis.

Abstract Objective: To describe the effectiveness of the intestinal antiparasitic treatment given to children ranging between 4 and 9 years old that were attended in the Health Center of the University of Quindío in the period of July 2017 and March 2018. Materials and methods: Prospective observational study. Data were extracted from medical records of patients with an age range of 4 to 9 years, who consulted at the Health Center of the University of Quindío and were diagnosed through coprological tests with Blastocystis and Giardiasis. The clinical records were selected by whose treatment was done with Nitazoxanide or Albendazole with coprological results of post-treatment check-up. Descriptive statistics are presented along with percentage of efficacy and tolerability. Results: From 15 children treated with Nitazoxanide, 10 responded to the treatment, who presented no parasites in the coprological check-up. The remaining population presented some type of parasitic infection (n = 5). With an efficiency of 83,3% (IC95% 32 - 82%) in blastocystis, and 57,1% (IC95% 32 - 82%) in giardiasis. Conclusion: Percentage results similar to those reported in the literature were evidenced, being more effective in blastocystis than in giardiasis.

Conocimientos, actitudes y prácticas sobre toxoplasmosis en dos comunas de Armenia, Quindío, con alta prevalencia de la infección / Knowledge, attitudes, and practices related to toxoplasmosis in two districts of high prevalence in Armenia, Quindío / Conhecimentos, atitudes e práticas sobre toxoplasmose em duas comunas de Armenia, Quindío, com alta prevalência de infecção

Resumen Objetivo: Describir los conocimientos, las actitudes y las prácticas acerca de la toxoplasmosis en dos comunas de Armenia, Quindío, con alta prevalencia de la infección. Metodología: Estudio descriptivo con población de dos comunas de Armenia, Quindío. Se aplicó un cuestionario autodiligenciado tipo conocimientos, actitudes y prácticas. Esta herramienta incluyó elementos sobre el parásito Toxoplasma gondii, sus vías de transmisión, aspectos clínicos, diagnósticos y de tratamiento generales, así como prácticas para evitar la infección. El instrumento se aplicó antes y después de una intervención educativa. Se describieron las frecuencias en el número de respuestas correctas antes y después de la intervención para cada comuna. Resultados: Participaron 27 personas, con una media de edad de 57 años. El 59 % fueron mujeres. El 48% había completado la educación media y el 40,7 % la primaria. El conocimiento del agente causal antes de la intervención fue del 22 %, mientras que posterior a la intervención fue del 92,3 % en la comuna 1 y del 81,8 % en la comuna 6. Posterior a la intervención, cerca del 90 % de los encuestados reconoció la retina como la principal estructura afectada y todos los encuestados reconocieron el consumo de agua hervida como factor protector. Conclusión: Los conocimientos sobre la toxoplasmosis en las dos comunas eran limitados. Luego de la intervención educativa, se evidenció un aumento en el porcentaje de respuestas correctas en la mayoría de las preguntas. Se recomienda realizar nuevas intervenciones educativas y en salud pública, para evaluar los efectos de estas a largo plazo.

Abstract Objective: To describe knowledge, attitudes and practices related to toxoplasmosis in two districts of high prevalence in Armenia, Quindío. Methodology: descriptive study; the population of two districts of Armenia, Quindío were engaged. A self-administered questionnaire regarding knowledge, attitudes, and practices was applied. This tool included elements related to Toxoplasma gondii, its transmission pathways, general clinical, diagnostic and treatment aspects, as well as practices to prevent infection. The instrument was applied before and after an educational intervention. Frequencies were described as the number of correct answers before and after the intervention for each district. Results: 27 people participated, with an average age of 57 years. 59 % were women; 48 % had completed high school and 40.7 % had completed elementary school. Before the intervention, the knowledge of the causal agent was 22 %, while after the intervention, it was 92.3 % in district 1 and 81.8 % in district 6. After the intervention, about 90 % of participants recognized the retina as the main compromised structure and all participants recognized the consumption of boiled water as a protective factor. Conclusion: The knowledge regarding toxoplasmosis in the two districts was limited. After the educational intervention, there was an increase in the percentage of correct answers in most of the questions. New educational and public health interventions are recommended to assess the long-term effects of these interventions.

Resumo Objetivos: O objetivo deste estudo é descrever os problemas, as ações e as práticas sobre a toxoplasmose nas comunidades da Armênia, Quindío, onde se nota alta prevalência da infecção. Metodologia: Este é um estudo descritivo que abrange uma população de duas comunas na Armênia, Quindío. Foi implementada uma ferramenta, que consiste em questionários destinados àquela população e aplicáveis pelos seus próprios membros, que correspondem a conhecimentos, atitudes e práticas. Essa ferramenta inclui elementos sobre o parasito Toxoplasma gondii, suas vias de transmissão, aspectos clínicos gerais, diagnósticos e tratamento, e práticas de prevenção. O instrumento foi aplicado antes e após uma intervenção educativa exata. Foram descritas as frequências do número de acertos, antes e depois da intervenção para cada comuna. Resultados: participaram 27 pessoas, com média de idade de 57 anos, das quais 59 % eram mulheres e 48 % tinham ensino médio completo e 40,7 % ensino primário. O conhecimento do agente causal antes da intervenção havia em 22 %, enquanto que após a intervenção, passou para 92,3 % na comuna 1, e 81,8 % na comuna 6. Após a intervenção, cerca de 90 % dos entrevistados reconheceram a retina como a estrutura mais afetada e todos os entrevistados reconheceram que o consumo de água fervida é um fator de proteção. Conclusão: Desconhecimento sobre a toxoplasmose nas duas comunas. Após a intervenção educativa, houve evidência de aumento do percentual de acertos na maioria das questões. Recomenda-se a realização de novas intervenções educacionais e de saúde pública, para avaliar os efeitos destas a longo prazo na populacão.

In vitro evaluation of new 4-thiazolidinones on invasion and growth of Toxoplasma gondii.

Treatments for toxoplasmosis such as pyrimethamine have shown numerous side effects. It has been reported that the likelihood of relapse associated with pyrimethamine-based therapy in patients with HIV and toxoplasmic encephalitis (TE) can have significant implications, even for patients who often develop new lesions in areas of the brain previously free of infection. This led us to research for new agents against Toxoplasma gondii. Recent findings have shown the potent biological activity of 4-thiazolidinones. We proposed to design and synthesize a new series of 2-hydrazono-4-thiazolidinones derivatives to evaluate the in vitro growth inhibition effect on T. gondii. The growth rates of T. gondii tachyzoites in Human Foreskin Fibroblast (HFF) cell culture were identified by two in vitro methodologies. The first one was by fluorescence in which green fluorescent RH parasites and cherry-red fluorescent ME49 parasites were used. The second one was a colorimetric methodology using ß-Gal parasites of the RH strain constitutively expressing the enzyme beta-galactosidase. The 4-thiazolidinone derivatives 1B, 2B and 3B showed growth inhibition at the same level of Pyrimethamine. These compounds showed IC50 values of 1B (0.468-0.952 µM), 2B (0.204-0.349 µM) and 3B (0.661-1.015 µM) against T. gondii. As a measure of cytotoxicity the compounds showed a TD50 values of: 1B (60 µM), 2B (206 µM) and 3B (125 µM). The in vitro assays and molecular modeling results suggest that these compounds could act as possible inhibitors of the Calcium-Dependent Protein Kinase 1 of T. gondii. Further, our results support the fact that of combining appropriate detection technologies, combinatorial chemistry and computational biology is a good strategy for efficient drug discovery. These compounds merit in vivo analysis for anti-parasitic drug detection.

Blastocystis Subtypes and Culture Characteristics of Isolates from Human Stools Related with the Presence of Gastrointestinal Symptoms: A Case-Control Study.

PURPOSE: To stablish if Blastocystis subtypes influences gastrointestinal symptoms. METHODS: Case-control study. We obtained sequencing for Blastocysts subtyping from 13 patients with gastrointestinal symptoms (diarrhea or abdominal pain) and 12 from individuals without symptoms. RESULTS: 12 sequences were from Subtype 2 and one from Subtype 3 in symptomatic individuals and nine samples were from Subtype 1, one from Subtype 2, and two from Subtype 3 in asymptomatic individuals. The prevalence of subtype 2 in symptomatic individuals was vastly different compared to the frequency in asymptomatic individuals (84.6% vs. 16.6%; OR 27.5 95% CI 3.2-233; Fisher exact test p = 0.0010201335). After in vitro culture, 22 isolates were obtained. Significant differences were observed for the 12 isolates from Subtype 2 that get a smaller number of total cells with dominant growth of vacuolar forms, compared with Subtypes 1 and 3, after eight days of culture. CONCLUSION: Our results suggest that gastrointestinal symptoms in Colombian individuals with Blastocystis infection depend on the infecting subtype with peculiar phenotypic characteristics in in vitro culture.

High frequency of ocular toxoplasmosis in Quindío, Colombia and risk factors related to the infection.

OBJECTIVES: To determine the frequency of retinochoroidal lesions by ocular toxoplasmosis and their relationships with risk factors, in residents of two districts with high exposure to Toxoplasma, in Armenia-Quindío, Colombia. METHODS: Cross-sectional analyses of fundoscopy screening, serological tests, and questionnaires were performed to determine risk factors associated with ocular toxoplasmosis retinochoroidal lesions. Differences in proportions were analyzed using the chi-squared test. RESULTS: Of 161 individuals examined, 17 (10.5%) exhibited retinochoroidal scars suggestive of old inactive Toxoplasma gondii infection. All 17 individuals were seropositive for T. gondii antibodies. Consumption of bottled water was protective against T. gondii infection among individuals in this study. There were no specific epidemiological risk factors associated with ocular toxoplasmosis retinochoroidal lesions. CONCLUSION: Ocular toxoplasmosis is an important cause of visual impairment in Armenia-Quindío, Colombia. The consumption of boiled or bottled water is a major preventive public health measure to reduce infection by T. gondii and the subsequent onset of OT.

Evaluation of the impact of the first evidence-based guidelines for congenital toxoplasmosis in Armenia (Quindío) Colombia: An observational retrospective analysis.

Background: Colombia implemented the world's first evidence-based guidelines for congenital toxoplasmosis in 2013, no evaluation of its impact has been reported. Methods: We reviewed the clinical charts of cases referred to the specialized consultation of the health care centre at Universidad del Quindío during an 18-year period (2001-2019), where the diagnosis criteria and the correlation between prenatal treatment and symptoms at birth were analysed. Additionally, we described the diagnosis criteria and treatment for mothers during pregnancy at a primary prenatal care centre in the city of Armenia during 2018. Institutional consent was obtained to review clinical charts. Findings: At the referral centre, we found that before the implementation, 27.3% did not have prenatal diagnosis but after implementing the clinical practice guidelines, all mothers were diagnosed during pregnancy. In addition, we observed that prenatal treatment was associated with fewer symptoms and this improved significantly over time after implementing the guidelines. At the primary health care centre in 2018, we found that all mothers were diagnosed and treated, as recommended by the national guideline. Interpretation: The national guideline has had a positive impact by improving early diagnosis and treatment of prenatal toxoplasmosis and reducing severe forms, as observed at the referral centre. Funding: Colombian Ministry of Science.

Ocular Toxocariasis in Parasitology Consultation in Quindío, Colombia: Description of Cases and Contact Studies.

We report diagnosis, treatment and evolution of cases of ocular toxocariasis in specialized consultation in Quindío, Colombia. No cases were seen during the 2000-17 period, but five cases were confirmed from November 2017 to March 2019; two children resulted with definitive loss of vision on the affected eye. Studies in contacts found that 12 of 19 (63%) family members and 15 of 25 (60%) children <15 years of age living on the same street were positive for IgG Toxocara antibodies. Epidemiological studies are necessaries to establish the reasons for the increase in cases at this region.

Human peripheral blood mononuclear cells as an ex vivo model to study the host parasite interaction in Toxoplasma gondii.

Toxoplasma gondii is a parasite that can invade any cell in the human body. Here, we implemented and described an ex vivo model with human peripheral blood mononuclear cells (PBMCs) without using culture supplements/antibiotics and without cryopreserved cells (EXMOWS) to study the interactions between T. gondii and human cells. To establish the EXMOWS, three independent tests were carried out. Firstly, blood samples from 5 individuals were included to assess the viability and adherence of PBMCs in plate culture. In a second trial, blood samples from three seropositive and two seronegative individuals for T. gondii were used to evaluate human PBMCs cells: parasites, multiplicity of infection (MOI) 1:1, 1:3 and 1:5 at different times post infection (1 h, 6 h and 24 h). The possible immunomodulatory effect of the infection for this EXMOWS were evaluated in a third trial where HFF cells were infected with T. gondii and co-cultured with PBMCs obtained from anti-Toxoplasma IgG positive and IgG negative individuals. One hour was enough time for T. gondii infection of human PBMCs and 2 h was the minimum incubation time to guarantee adherence before carrying out any infection assay. A minimum of 1:3 MOI was necessary to guarantee efficient infection in human PBMCs with T. gondii RH-GFP. All protocols, including PBMCs isolation and stimulation, should be conducted the same day. This EXMOWS can be adapted to study the early stages of interaction with other microorganisms of human interest, without need of using cryopreservation and supplements/antibiotics.

Serotyping, host genes and cytokines response in human ocular toxoplasmosis.

In human ocular toxoplasmosis, serotype is related with greater severity. We analyzed Toxoplasma GRA6 serotype in 23 patients with ocular toxoplasmosis (13 confirmed, two co-infections- and eight unconfirmed cases) and 20 individuals chronically infected with Toxoplasma but without ocular involvement. In patients with ocular toxoplasmosis, we also studied host gene polymorphisms related to immune response (IL-1ß; IL-1α; IL-10; IFN-γ; TNF-α, IL-12), IL-17R, TLR-9, and P2RX7. Additionally, eight patients were studied for the production of TNFα, IL1-ß, IFN-γ and IL-10 by their peripheral leukocytes after ex vivo stimulation with soluble Toxoplasma antigens. There were no differences in the distribution of serotypes (GRA6-I versus GRA6 non-I) between infected individuals with- or without ocular involvement. Seropositivity for GRA6-I was associated with higher number of retinal lesions and higher levels of IL-1ß. Two polymorphisms were associated with specific clinical manifestations of ocular toxoplasmosis: IL-10 -819 C/T with bilateral lesions and IL-12 + 169,774 A/C with synechia. Higher levels of IL-10 were found in patients with the allele G/G at the polymorphic region IL-10 -1082. People with a GRA6 I serotype and possessing the allele G/G at the polymorphic region TNFα-857 suffered from an increased number of retinal lesions. We found a positive association between host cytokine genes polymorphisms and GRA6 serotypes correlated with specific clinical manifestations and immune response in ocular toxoplasmosis.

First Detection of Toxoplasma gondii DNA in a Wild Bat from Colombia.

INTRODUCTION: Toxoplasma gondii infections have been reported for many warm-blooded animals around the world including chiropterans. However, in Colombia, the country that holds the highest taxonomic richness of this order of mammals in the Neotropics, up to date there are no reports of T. gondii in bats (Carollia brevicauda). PURPOSE: The objective of the present study was to detect T. gondii DNA from internal bat organs from Quindío, Colombia. RESULTS: We report the first detection of T. gondii DNA from internal bat organs in the department of Quindio, Central Andes of Colombia. Out of three silky short tail bat (Carollia brevicauda) specimens collected at the natural reserve "La Montaña del Ocaso", organs were recovered (lungs, liver, heart, kidneys, small and large intestine) and tested for T. gondii through PCR for B1 sequence, with 1/3 (33.3%) positive result for the presence of T. gondii DNA in bat kidney tissues. CONCLUSION: Taking into consideration the high diversity of bat species in Colombia, and the complexity of the ecological and functional relationships that these organisms establish in the ecosystems they inhabit, we discuss on the urgent need for more detailed research and surveys for Toxoplansma in bats and other mammalian wild species.

Severe acute multi-systemic failure with bilateral ocular toxoplasmosis in immunocompetent patients from urban settings in Colombia: Case reports.

PROPOSE: To report two cases of severe acute multi-systemic failure with bilateral ocular toxoplasmosis in immunocompetent patients from urban settings in Colombia. OBSERVATIONS: We report two immunocompetent male patients aged 44- and 67-years-old who, despite not having visited the Amazonian region in Colombia, had severe bilateral posterior uveitis and extensive-bilateral macular lesions and multiple organ failure that required admission to an intensive care unit. Toxoplasma gondii was positive by PCR assay in vitreous humor samples. Patients were treated with intravitreal clindamycin and dexamethasone in addition to systemic treatment with trimethoprim-sulfamethoxazole. In both patients, infection by atypical strains was confirmed; in one case by serotyping and in another one by genotyping (ROP 18 virulent allele). After 2 and 4 months of treatment respectively, the patients showed improvement of the posterior uveitis and its systemic manifestations. However, there was no significant visual acuity improvement due to bilateral extensive macular involvement. CONCLUSIONS AND IMPORTANCE: Clinicians should be aware that toxoplasmosis originating from South America could be associated with severe acute multisystemic and intraocular bilateral involvement, even in patients with no history of exposure to jungle environments.

In memoriam Doctor Miguel Guzmán Urrego 1933-2019 / In memoriam Doctor Miguel Guzmán Urrego 1933-2019

El Dr. Miguel Guzmán, pionero de la microbiología en Colombia falleció en el mes de Abril de 2019 y desde Infectio, de quien fue su fundador y primer editor, queremos rendirle un homenaje por su contribución al desarrollo de la investigación y la enseñanza de la microbiología médica, haciendo un resumen de su vida y obra.

Dr. Miguel Guzman, pioneer of microbiology in Colombia passed away in April 2019 and from Infectio, whose founder and first editor, we want to pay tribute to him for his contribution to the development of research and teaching of medical microbiology, making a summary of his life and work.