Seroprevalencia y factores de riesgo asociados a toxoplasmosis gestacional en el Nororiente Colombiano / Seroprevalence and risk factors for congenital toxoplasmosis in the northeastern region of Colombia / Soroprevalência e fatores de risco associados à toxoplasmose gestacional no nordeste da Colômbia

Introduction: Toxoplasmosis is a zoonosis prevalent in one-third of the world's population, adversely affecting maternal-fetal health by causing varying degrees of damage to the fetus. Objective: To assess the seroprevalence of Toxoplasma gondii IgG and IgM antibodies and associated risk factors in first-trimester pregnant women in Cúcuta, Colombia, in 2018. Materials and Methods: Cross-sectional and correlational study in 111 women who voluntarily participated. Specific IgM and IgG antibodies were detected by luminescence immunoassay (LIA). Results: Total seropositivity for IgM and IgG was 19.8% and 35.1%, respectively, 11.7% was for IgM only, and 53.2% corresponded to the overall seronegativity rate for T. gondii. Risk factors (CI = 95%) such as undercooked meat consumption (54.1% of cases, OR = 1.8, p = 0.120), tap water consumption (48.6%, OR = 1.4, p = 0.421), and goat or cow raw milk consumption (39.6%, OR = 0.78, p = 0.553) were identified; in addition, living with cats (23.4%) was identified as a risk factor significantly associated with parasite seropositivity (OR = 2.8, p = 0.025). Discussion and Conclusions: Our findings showed a possible risk of primary infection in more than half of the pregnant population, given the seronegativity against the parasite. A considerable frequency of suspected cases of very recent infection was also found. In addition to being associated with a previously recognized risk factor, this fact suggests the presence of other dietary risks that should be addressed through prevention strategies during prenatal care and the need to strengthen event surveillance.

Introdução: A toxoplasmose é uma zoonose prevalente em um terço da população mundial, que afeta negativamente a saúde materno-fetal, causando diversos graus de danos ao feto. Objetivo: Propôs-se avaliar o estado sorológico IgG e IgM anti - Toxoplasma gondii e fatores de risco relacionados, em gestantes no primeiro trimestre em Cúcuta, Colômbia, no ano de 2018. Material e Métodos: Estudo transversal e correlacional em Participaram 111 mulheres voluntariamente, que foram testadas para IgM e IgG específicos pelo imunoensaio LIA. Resultados: 19,8% e 35,1% do total de soropositividade foram encontrados para IgM e IgG, respectivamente, 11,7% foi apenas para IgM e 53,2% corresponde à frequência de soronegatividade geral para T.gondii; Foram identificados fatores de risco (IC=95%) , como consumo de carne mal cozida (54,1% dos casos, OR= 1,8, p=0,120 ), água da torneira (48,6%, OR=1,4, p=0,421), cru leite de cabra ou vaca (39,6%, OR=0,78, p=0,553 ), além de conviver com gatos (23,4%), sendo este último significativamente associado à soropositividade ao parasita ( OR=2,8 , p =0,025 ). Discussão e conclusões: Nossos achados revelam um possível risco de infecção primária em mais da metade da população gestante dada a sua soronegatividade contra o parasita, mas também uma frequência considerável de casos com suspeita de infecção muito recente, que, além de estar associada a um fator de risco previamente reconhecido , sugere outros aspectos de risco em torno da alimentação que devem ser impactados por meio de estratégias de prevenção durante o pré-natal, sugerindo a necessidade de fortalecer a vigilância em torno do evento.

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.

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.

Coinfections and differential diagnosis in immunocompetent patients with uveitis of infectious origin.

BACKGROUND: Making a definite diagnosis of infectious uveitis is a challenging task because many other infectious, and non-infectious uveitis, may have similar non-specific symptoms and overlapping clinical appearances. Co-infections in immunocompetent patients are not frequently proved with traditional serologic-diagnostic tools. METHODS: Descriptive transversal study, in a Uveitis Service of an Ophthalmology Reference Center, in Bogotá, Colombia, from July 2014 to February 2016. Aqueous humor (AH) and/or vitreous fluid, blood and serum samples were collected from consecutive patients suspected of having infectious uveitis. The diagnosis of ocular toxoplasmosis (OT) was confirmed by the Goldmann-Witmer coefficient (GWC) and by polymerase chain reaction (PCR). Differential diagnosis by PCR in AH was done for viral origin such as Cytomegalovirus (CMV), Herpes simplex virus type 1 (HSV1), Herpes simplex virus type 2 (HSV2), Varicella zoster virus (VZV), Epstein-Barr virus (EBV) and Mycobacterium tuberculosis. RESULTS: In 66 Colombian patients with uveitis of presumed infectious origin: 22 (33.3%) were confirmed as OT, 16 (24.2%) as undetermined OT, five (7.5%) as co-infections and 23 (34.8%) as other uveitis. Toxoplasma coinfection with M. tuberculosis was identified in one case by PCR and in four cases with HSV by GWC. The initial clinical diagnosis changed, after laboratory examination, in 21 cases (31.8%). CONCLUSIONS: Clinical diagnosis can be changed by laboratory examination in a significant proportion of cases of uveitis. Diagnosis of OT should combine the use of PCR and GWC to reach the maximum of confirmation of cases. The use of multiple laboratory methods is necessary to identify co-infections and viral infections that can mimic OT in immunocompetent patients.

Th1 and Th2 immune response to P30 and ROP18 peptides in human toxoplasmosis.

We determined the specific lymphocyte proliferative response and cytokine profile production regarding Toxoplasma P30 (2017 from virulent and non-virulent strain) and ROP18 protein-derived peptides (from clonal lineages I, II and III) in 19 patients having ocular toxoplasmosis, five suffering chronic asymptomatic infection, nine with congenital toxoplasmosis and eight Toxoplasma negative people. A Beckman Coulter FC500 flow cytometer was used for determining antigen-specific T cells (CD3+ CD4+ or CD3+ CD8+ cells) in peripheral blood culture. IFN γ and IL10 levels were determined in culture supernatants. Specific CD4+ and CD8+ T cell response to total antigen and P30- and ROP18-derived peptides was observed in infected people. Ocular toxoplasmosis patients had a preferential Th2 response after antigenic stimulation. Non-virulent peptide 2017 was able to shift response toward Th1 in congenitally infected children and virulent peptide 2017 induced a Th2 response in chronically infected, asymptomatic people. An immune response in human toxoplasmosis after ex vivo antigenic stimulation was Th1- or Th2-skewed, depending on a patient's clinical condition. Colombian ocular toxoplasmosis patients' immune response was Th2-skewed, regardless of the nature of antigen stimulus.