Fabiana Lora

First Colombian Multicentric Newborn Screening for Congenital Toxoplasmosis

Aims To determine the incidence of congenital toxoplasmosis in Colombian newborns from 19 hospital or maternal child health services from seven different cities of five natural geographic regions (Caribbean, Central, Andean, Amazonia and Eastern). Materials and Methods We collected 15,333 samples from umbilical cord blood between the period of March 2009 to May 2010 in 19 different hospitals and maternal-child health services from seven different cities. We applied an IgM ELISA assay (Vircell, Spain) to determine the frequency of IgM anti Toxoplasma. The results in blood cord samples were confirmed either by western blot and repeated ELISA IgM assay. In a sub-sample of 1,613 children that were negative by the anti-Toxoplasma IgM assay, the frequency of specific anti-Toxoplasma IgA by the ISAGA assay was determined. All children with positive samples by IgM, IgA, clinical diagnosis or treatment during pregnancy were recalled for confirmatory tests after day 10 of life. Results 61 positive samples for specific IgM (0.39%) and 9 positives for IgA (0.5%) were found. 143 questionnaires were positive for a clinical diagnosis or treatment for toxoplasmosis during pregnancy. 109 out of the 218 children that had some of the criteria for postnatal confirmatory tests were followed. Congenital toxoplasmosis infection was confirmed in 15 children: 7 were symptomatic, and three of them died before the first month of life (20% of lethality). A significant correlation was found between a high incidence of markers for congenital toxoplasmosis and higher mean annual rainfall for the city. Conclusions Incidence for congenital toxoplasmosis is significantly different between hospitals or maternal child health services from different cities in Colombia. Mean annual rainfall was correlated with incidence of congenital toxoplasmosis.

Prevalencia de giardiasis y parásitos intestinales en preescolares de hogares atendidos en un programa estatal en Armenia, Colombia

OBJETIVO: El proposito de este estudio es el de obtener datos sobre la giardiasis y el parasitismo intestinal en una muestra significativa de los ninos en edades pre-escolares de los hogares de madres comunitarias del Instituto Colombiano de Bienestar Familiar (ICBF). MATERIALES Y METODOS: Se recolecto un seriado de tres muestras de heces en 328 ninos, con previo consentimiento del tutor legal. Se le realizo el analisis de laboratorio por examen directo microscopico y macroscopico utilizando Lugol al 1 %, solucion salina al 0,83 %, solucion salina-eosina, Kato Katz y formol-eter o metodo de concentracion de Ritchie (prueba comprobatoria). Las muestras positivas se conservaron en formol salino. RESULTADOS: Los parasitos con potencial patogeno tuvieron las siguientes prevalencias: Ascaris lumbricoides 2,4 %, Hymenolepsis nana 0,6 %, Trichuris trichura 2,1 %, Blastocystis hominis 6,1 % y Giardia lamblia 13 %. CONCLUSIONES: Este estudio muestra la baja frecuencia de los helmintos con respecto a los protozoos, por lo tanto estrategias de desparasitacion masiva con dosis unicas de Albendazol no tienen utilidad. Se recomienda la vigilancia periodica de parasitos por examenes en estos ninos. Se confirma que el parasito patogeno mas prevalente es Giardia lamblia en los ninos de las guarderias infantiles del ICBF. La prevalencia de Giardia no se relaciono de manera estadisticamente significativa con el estado nutricional de los ninos de las guarderias del ICBF. La mayoria de ninos infectados por Giardia son asintomaticos.

Evaluation of IgG anti-toxoplasma avidity and polymerase chain reaction in the postnatal diagnosis of congenital toxoplasmosis.

Confirmatory tests for congenital toxoplasmosis were evaluated in 23 infected and 31 uninfected newborns. Conventional polymerase chain reaction was better than real-time polymerase chain reaction, but did not identify additional cases. Avidity tests added 2 new cases that were not identified by other criteria. Overall sensitivity was 82.6%. Avidity assay, but not polymerase chain reaction, increased the sensitivity of confirmatory assays in congenital toxoplasmosis.

Striking Divergence in Toxoplasma ROP16 Nucleotide Sequences From Human and Meat Samples

BACKGROUND ROP16 is a protein kinase of Toxoplasma gondii identified in the mouse model as a virulent marker, but it is unknown whether this finding is relevant in human toxoplasmosis. METHODS We obtained the Toxoplasma ROP16 locus DNA sequence in samples from 12 patients with ocular toxoplasmosis, 1 sample from a patient with congenital toxoplasmosis, 22 samples from soldiers operating in the jungle, 2 samples from urban soldiers, and 10 samples from meat for human consumption. An enzyme-linked immunosorbent assay specific for antibodies against the ROP16 mouse-virulent peptide was performed in 46 serum specimens from patients with ocular toxoplasmosis and in 28 serum specimens from patients with chronic asymptomatic infection, of whom 19 had congenital infection and 11 had toxoplasmic lymphadenitis. RESULTS We found a striking divergence of the ROP16 nucleotide sequences. Ten of 12 sequences (83.3%) from patients with ocular toxoplasmosis clustered with those of mouse-virulent strains, whereas 7 of 7 ROP16 sequences (100%) from meat were clustered with those of mouse-avirulent strains. Only 11 of 104 serum specimens (10.5%) had specific antibodies against the mouse-virulent peptide, and there was no association between clinical forms and positive results of serological assays. CONCLUSIONS The majority of ROP16 nucleotide sequences from Colombian patients with ocular toxoplasmosis belonged to the group of mouse-virulent strains.

Determinación de la actividad antifúngica de extractos de Lantana camara frente a Candida spp.

Objetivo. El objetivo del trabajo fue determinar si los extractos de la planta Lantana camara presentan actividad antifungica frente a seis especies de Candida spp y un aislamiento humano de origen primario. Materiales. Se obtuvieron los extractos etanolicos totales por el metodo de percolacion y se hizo fraccionamiento cromatografico con eluyentes de diferente polaridad. Se caracterizaron los grupos funcionales mediante espectroscopia infrarroja. La actividad antifungica se evaluo frente a seis especies de Candida spp. (C. albicans, C. dubliniensis, C. krusei, C. guillermondii, C. tropicalis, C. parapsilosis y un aislamiento primario de C. albicans). La prueba de inhibicion del crecimiento se hizo con un ensayo en suero humano, observando con absorbancia a 600 nm las curvas de crecimiento relacionadas.

Estandarización del inmunoensayo ELISA para la detección de IgG anti-Toxoplasma gondii en ratón

* Grupo de Parasitologia Molecular -GEPAMOL- Centro de Investigaciones Biomedicas, Facultad de Ciencias de laSalud, Universidad del Quindio.Correspondencia: Jorge E. Gomez Marin, Grupo Estudio en Parasitologia Molecular (GEPAMOL), Centro deInvestigaciones Biomedicas Universidad del Quindio, Armenia (Q) Tel/Fax: +57-67-460168e-mail: gepamo2@uniquindio.edu.coNESTOR IVAN CARDONA*, FABIANA LORA* y JORGE ENRIQUE GOMEZ*