Objective: To estimate intestinal coccidiae infection prevalence of in asymptomatic children from a marginal community in Lima. Material and Methods: Stool samples were collected from 79 asymptomatic children aged 7 months through 7 year-old from Asentamiento Humano “Las Casuarinas de Villa”. Direct smear and colored frotis by Kinyoun technique were prepared. Another portion was placed in small bottles with potasium bicromatum 2,5% to obtain sporulation. After 10 days, frotis were colored by Kinyoun. Results: Direct smear detected one sample with Cryptosporidium (1,3%). In frotis colored before sporulation, 3 with Cryptosporidium (3,8%) were found and one with Isospora belli (1,3%); in frotis colored post-sporulation 6 samples with Cryptosporidium (7.59%) were detected and one with Isospora belli. Conclusion: Sporulation increases Cryptosporidium detection.

Objetivos: Caracterizar las moléculas de respuesta humoral anti Paragonimus mexicanus/P. peruvianus para diferenciar la infección en fase aguda y fase crónica, mediante la evaluación de la dinámica de la respuesta inmune. Diseño: Observacional, longitudinal. Institución: Instituto de Medicina Tropical Daniel A. Carrión, Facultad de Medicina, UNMSM Material biológico: Animales de experimentación. Principales medidas de resultados: Determinación de IgG e IgM anti Paragonimus. Resultados: Existió diferencia significativa de medias de la DO entre los grupos crónico y no infectados para los anticuerpos IgG anti ES de Paragonimus. Los anticuerpos IgM anti Paragonimus tuvieron una ligera elevación entre los días 7 a 20 post inoculación (pi), y una tendencia hacia la disminución entre los días 40 y 60 pi. Conclusiones: La dinámica de producción de anticuerpos IgG e IgM anti P...

In this paper, the fullest information available about the Acanthocephalan discovered in Peru is presented, but also new hosts.

Objective: To determine the prevalence of human fasciolosis in an endemic area by means of an enzyme-linked immunosorbent assay (ELISA) using cystatin as a capture agent for the detection of specific antibodies to Fasciola hepatica cysteine proteinases. Material and methods: An ELISA plate was sensitized with cystatin, incubated with excretory-secretory products of adult flukes, and followed by standard ELISA procedures. Clinical applicability of the cystatin capture ELISA for the immunodiagnosis of fasciolosis was tested with 200 serum samples of children and adults from an endemic area in Chupaca province, Junin department. Results: Serum samples from the endemic area tested by cystatin capture ELISA showed 27/ 200 (13,5%) of positive cases. Conclusions: Fasciolosis remains a major health problem at Chupaca province, Junin department.

Objective: To standardize ELISA technique for human Strongyloides stercoralis infection diagnosis. Material and methods: A crude antigen was prepared using filariform larvae obtained from positive stool samples cultured with charcoal. Harvested larvae were crushed by sonication and washed by centrifugation in order to obtain protein extracts to be used as antigen. Final protein concentration was 600 µg/mL. Several kinds of ELISA plates were tested and antigen concentration, sera dilution, conjugate dilution and cut off were determined to identify infection. Sera from patients with both hyperinfection syndrome and intestinal infection demonstrated by parasitological examination were positive controls and sera from people living in non-endemic areas with no infection demonstrated by parasitological examination were negative controls. Results: Best values were 5 µg/mL for antigen, 1/64 fo...

In this paper, the fullest information available about the Acanthocephalan discovered in Peru is presented, but also new hosts.

OBJECTIVE: To describe the experience with ivermectin and thiabendazole in patients attended at the Tropical Medicine Institute “Daniel A. Carrión”- UNMSM. MATERIAL AND METHODS: During 2001 and 2002, ivermectin (0,2 mg/kg in single dosis) and thiabendazole (25 mg/kg/3days) were administered to 22 (Group 1) and 20 (Group 2) patients with diagnosis of Strongyloides stercoralis in stools. Controls were performed between 20 and 40 days following treatment. RESULTS: Mean age was 21,8 years (SD 22,6) for group 1 and 33,5 years (SD 14,2) for group 2. There were 12 males (54,5%) in group 1 and 7 (35%) in group 2. Ivermectin was 100% efficient while thiabendazole was 95%; only one case needed a second cycle because of high amount of parasites from the beginning; his next control was negative. Most frequent symptoms were diarrhea (71,4%), abdominal pain (61,9%) and epigastric pain (47,6%); al...

OBJECTIVE: To assess the prevalence of paragonimosis among elementary school students from three villages of Condebamba valley, Cajamarca - Perú. MATERIAL AND METHODS: 77 school-age children underwent parasitologic examination in stools, skin test and counterimmunoelectrophoresis in those positive for skin reactivity. RESULTS: From 77 skin tests performed, 2 were positive (2,6%), which were also positive by counterimmunoelectrophoresis. All 77 stool samples were negative for Paragonimus eggs. CONCLUSION: These results showed a decreasing prevalence of human paragonimiasis among Condebamba valley children.

Background: Paragonimiasis is a lung disease caused by Paragonimus trematodes genus. Human infection laboratory diagnosis is usually done by detection of parasite eggs in sputum or feces; however, findings may be negative and alternative diagnostic methods are required. Objectives: To compare three serologic tests for detection of Paragonimus mexicanus somatic antigen (PmAS) antibodies in serum samples of cats infected experimentally. Design: Experimental study. Setting: Instituto de Medicina Tropical “Daniel A. Carrión” bioterium, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Domestic cats 4-6 years old and P. mexicanus (PmAS) crude somatic antigen. Interventions: Blood samples were collected from twelve domestic cats infected with P. mexicanus. Serum samples were evaluated by enzyme-linked immunosorbent assay (ELISA), double diffusio...

Objective: To estimate seroprevalence of human toxocariosis in Lima inhabitants. Design: Cross-sectional study, non aleatory selection. Material and methods: To people living in Lima city urban marginal communities, an interview and clinical examination were done and serum samples obtained to detect antibodies against Toxocara by ELISA technique. Stool samples were also obtained to check parasites causing cross reactions with serology. Results: From 553 persons examined 23,3% were reactive. There were no sex differences and ELISA results related to anemia, leucocytosis, eosinophilia or intestinal parasites. People older than 15 yearold had twice the possibility to be reactive. Most frequent symptom in positive individuals was decrease of visual capacity. Most frequent parasites were Blastocystis hominis, Entamoeba coli, Giardia lamblia. Conclusions: Human toxocariosis is frequent in Lima...

Objective: To determine human toxocariosis prevalence in subjects presenting suspicious ocular symptoms. Material and methods: Subjects with symptoms and suspicion of intraocular toxocariosis damage attended at various Lima hospitals ophtalmology services were studied. Blood samples were obtained and Toxocara serology by ELISA technique was done, along with leukocyte counts. An epidemiological questionnaire was also applied to identify behaviors associated to infection risk. Results: Forty-five persons were studied, 19 male and 26 female, 55,6% were reactive by ELISA test. No differences in sex and serology results were observed; among participants between 15 and 45 years old, 63% were reactive. There were no significant differences in the epidemiological factors studied. No association between eosinophilia and serology was observed. Conclusions: Human infection by Toxocara is frequent i...

OBJECTIVES: To assess the prevalence of E. histolytica and E. dispar in a marginal population of Callao, Lima, using ELISAs. MATERIAL AND METHODS: Two ELISAs were used, one of them for both Entamoeba species (Entamoeba-ELISA), and an E. histolytica-specific ELISA. RESULTS: 128 stool samples from randomized Callao inhabitants were microscopically examined. Thirteen (10%) were microscopically diagnosed as having E. histolytica or E. dispar infection; and 7 (6%) were positive to Entamoeba–ELISA (sensitivity = 54%). Five of the 115 samples without cysts of E. histolytica or E. dispar were Entamoeba ELISA positive (specificity = 96%). All samples were negative to the E. histolytica-specific ELISA. CONCLUSIONS: The correlation between the microscopical identification and Entamoeba-ELISA was not good, it may be due to an overvaluation of the morphological diagnosis.

Objetive: To standardise ELISA technique for Toxocara canis human infection diagnosis by using excreted-secreted antigen prepared in our country. Material and methods: T. canis eggs were collected by incubation with formalin (2%) at 28oC in order to obtain third stage larvae that were freed and incubated in RPMI at 37°C for 7 days; the medium was replaced by a similar one and stored at - 20°C. Antigen was concentrated and protein dosage was made. Sera from patients with toxocariasis and newborns were used as positive and negative controls by ELISA technique, dilutions ¼ to 1/1024. Polystyrene plates were sensitised with antigen in several concentrations and conjugated peroxidase with horseradish IgG, anti human IgG and substrate OPD were used. Absorbance was read with spectrophotometer (Multiskan plus labsystems) at 492 nm. Cut off point was determined by negative sera absorbencies ar...

Objetivos: Implementar el ensayo PCR-RFLP-ITS2 para diferenciar especies del género Anopheles presentes en distintas localidades del Perú. Diseño: Descriptivo, observacional. Institución: D. A. Microbiología Médica, Facultad de Medicina, UNMSM; Centro de Biotecnología, Universidad Iberoamericana de Ciencias y Tecnología; Laboratorio Entomología Médica, Sección Parasitología, Instituto de Salud Pública; Laboratorio de Entomología Médica, Laboratorio de Referencia Regional, Gerencia Regional de Salud La Libertad; Dirección Ejecutiva de Salud Ambiental, Sub Región de Salud “Luciano Castillo Colonna”, DIRESA Piura. Material biológico: Mosquitos del género Anopheles. Intervenciones: Extracción de ADN de Anopheles Principales medidas de resultados: Se utilizó 79 ejemplares del género Anopheles de cinco departamentos del país. Se extrajo ADN de una parte de cada mosqu...

En el presente estudio se describe la aplicación de pruebas estandarizadas para el diagnóstico inmunológico de la hidatidosis humana en el Instituto de Medicina Tropical "Daniel A. Carrión", Universidad Nacional Mayor de San Marcos, Lima, Perú. Estas se emplearon para obtener la confirmación prequirúrgica de la parasitosis en situaciones clínicas, y para la detección de portadores asintomáticos de quistes hidatídicos mediante encuestas. Los resultados se utilizaron como fuente de datos para evaluar la calidad de la información que sobre el número de casos de la afección en distintas áreas ecológicas, se obtiene a partir de los casos hospitalarios notificados a los niveles oficiales. Los resultados demuestran la utilidad que puede brindar la extensión de la cobertura de los servicios para el inmunodiagnóstico de la hidatidosis a las áreas endémicas del país con fines ...

Objetivos: Detectar el genoma proviral de HTLV-1 mediante el desarrollo de reacción en cadena de la polimerasa (PCR). Diseño: Descriptivo. Institución: D.A. Microbiología Médica, Facultad de Medicina, UNMSM. Participantes: Personas con y sin sospecha de HTLV-I. Principales medidas de resultados: detección de HTLV-1 mediante PCR. Resultados: El 71,4% de los pacientes con sospecha clínica de HTLV-I fue reactivo por métodos Inmunológico. Elisa HTLV I-II Biokit detectó 5 casos reactivos (X=2,359 ± DE: 0,7309); los dos casos con sospecha clínica de HTLV- I fueron no reactivos (DO: 0,007 y 0,04); los tres casos con antecedente clínico de estrongiloidiosis fueron no reactivos al Elisa (DO: 0,029, 0,001 y 0,00). El promedio de los sueros no reactivos con antecedente clínico de HTLV-1 y estrongiloidiosis fue 0,0154 ±0,018. En el grupo de voluntarios sanos, el promedio de las DO fue...