Claudia Menghi

Dientamoeba fragilis: Técnicas moleculares para dilucidar su modo de transmisión

RESUMEN Dientamoeba fragilis es un protozoariointestinal humano. Su prevalencia mundial oscilaaproximadamente entre 1,4% y 19%. Muy pocose sabe actualmente sobre su virulencia,patogenicidad, modo de transmision; y no se haidentificado aun un estadio quistico. Un amplioespectro de sintomas gastrointestinales ha sidodescrito en un gran numero de pacientesinfectados: diarrea, flatulencia, colicos, y perdidade peso, entre otros. La asociacion simultaneaentre las infecciones causadas por D. fragilis y Enterobius vermicularis llevo a Burrows ySwerdlow en 1956 a especular sobre el probablerol de los huevos de E. vermicularis en larestriccion de uno de los cuatro pacientes (calles1, 2 y 3) y los productos de PCR de la cepa controlde D. fragilis , obtenidos luego del tratamientocon la misma enzima (calles 4, 5 y 6). (Figura3). Una “semi-nested” PCR con los “primers”DF5 y TRD3 genero un producto de PCR finalque contenia cinco sitios de restriccion para Hinf I.Cinco fragmentos de restriccion (597 pb, 209pb, 127 pb, 87 pb y 76 pb) se muestran en laFigura 3, calle 2. Otra “semi-nested” PCR sedesarrollo con la combinacion de los “primers”TRD5 y DF3. El producto de PCR obtenido nocontenia ningun sitio de restriccion para

Evaluación de la disfunción vaginal en mujeres embarazadas sintomáticas y asintomáticas mediante la utilización de los estados vaginales básicos (EVB) y su comparación con el estudio microbiológico convencional

Infections of the lower genital tract associated to maternal and perinatal complications frequently occur during pregnancy. The aim of this study was to evaluate vaginal dysfunction through the analysis of basic vaginal states (BVS) using the methodology of balance of the vaginal content (BAVACO) and to compare it with the microbiological study of candidiasis, trichomoniasis and bacterial vaginosis (BV). Pregnant patients (1238) were examined from 2010 to 2012. In asymptomatic (A) (n: 1046) and symptomatic pregnant women (S) (n: 192) BVS I was 59.5% and 26% of the patients, respectively. BVS II was observed in 19.7% of A and in 17.2% of S. BVS III was only detected in A in 0.4%. BVS IV was observed in 14.4% of A and in 38% of S. BVS V was detected in 6% of A and in 18.8% of S. Yeasts were associated to BVS I and II in 55.5% and 23.2% of A, respectively; and in 32.4% and 31% of S, respectively. Trichomonas were associated to BVS I in 50% of A, to IV in 44.4% of S and to V in 33.3% of S. BAVACO susceptibility to detect yeasts was 80.4% and 85.5% in A and S, respectively; 40% and 75% in A and S, respectively, to detect trichomonas and 100% in A and S to detect BV. BAVACO specificity was 100% for all pathogens in A and S. The study of BVS proved useful as a guide to evaluate vaginal dysfunction, regardless of symptomatology. Therefore, this study is recommended as prenatal control.

Unusual localization of an hydatid cyst: first reported case in Buenos Aires, Argentina

Hydatidosis is a parasitic infection caused by the tapeworm larva of Echinococcus spp. Its relevance lies in its wide distribution, great number of clinical cases and outstanding morbility. Hydatid infection of the orbit comprises far less than 1% of the total incidence. This is a case of a patient from Argentina complaining of a two-week evolution proptosis of the right eye. A microscopic examination revealed the presence of protoscolices of Echinococcus spp. in the fluid obtained during the surgical proceedings. The patient was treated with oral albendazole. To our knowledge, this is the first case of ocular hydatidosis diagnosed in the city of Buenos Aires, Argentina.

Difilobotriosis humana: primer caso por consumo de sushi en Buenos Aires, Argentina

* Area Parasitologia, Departamento de Bioquimica Clinica, Facultad de Farmacia y Bioquimica. Hospital deClinicas, Universidad de Buenos Aires.** Servicio de Dermatologia, Facultad de Medicina, Hospital de Clinicas, Universidad de Buenos Aires.Correspondencia: Claudia I. Menghi Teodoro Garcia 2350 7° A (05411)47763979. Ciudad de Buenos Aires,Argentina. e-mail: cmenghi@fibertel.com.ar

Optimization of Trichomonas vaginalis Diagnosis during Pregnancy at a University Hospital, Argentina

The aim of this study was to evaluate different methods for Trichomonas vaginalis diagnosis during pregnancy in order to prevent maternal and perinatal complications. A total of 386 vaginal exudates from pregnant women were analyzed. T. vaginalis was investigated by 3 types of microscopic examinations direct wet mount with physiologic saline solution, prolonged May-Grunwald Giemsa (MGG) staining, and wet mount with sodium-acetate-formalin (SAF)/methylene blue method. PCR for 18S rRNA gene as well as culture in liquid medium were performed. The sensitivity and specificity of the microscopic examinations were evaluated considering the culture media positivity or the PCR techniques as gold standard. The frequency of T. vaginalis infection was 6.2% by culture and/or PCR, 5.2% by PCR, 4.7% by culture, 3.1% by SAF/methylene blue method and 2.8% by direct wet smear and prolonged MGG staining. The sensitivities were 83.3%, 75.0%, 50.0%, and 45.8% for PCR, culture, SAF/methylene blue method, and direct wet smear-prolonged MGG staining, respectively. The specificity was 100% for all the assessed methods. Microscopic examinations showed low sensitivity, mainly in asymptomatic pregnant patients. It is necessary to improve the detection of T. vaginalis using combined methods providing higher sensitivity, such as culture and PCR, mainly in asymptomatic pregnant patients, in order to prevent maternal and perinatal complications.

Pulmonary hydatidosis from Southern Argentina

Hydatidosis or cystic echinococcosis is a zoonosis caused by the larval stage of the cestode Echinococcus. Even though different measures are taken including the use of a vaccine in livestock to stop transmission, the continuous diagnoses of cases, mainly of liver and pulmonary hydatidosis, show the failure of the control programs for hydatidosis in our country. A clinical case of pulmonary hydatidosis in a patient from a rural endemic area in Southern Argentina is described.

Trypanosoma cruzi en el líquido cefalorraquídeo de un paciente con SIDA

La enfermedad de Chagas es una parasitosis causada por Trypanosoma cruzi y es endemica en Latinoamerica. La infeccion puede reactivarse en pacientes inmunocomprometidos y provocar meningoencefalitis difusa o lesiones pseudotumorales; ambas resultan clinica y radiologicamente indistinguibles de otras patologias neurologicas que afectan a pacientes con SIDA, como la toxoplamosis cerebral. La reactivacion de la infeccion de Chagas en inmunodeprimidos se confirma por la presencia de T. cruzi. Al Hospital de Clinicas concurrio un paciente de 35 anos procedente de la provincia del Chaco, con un cuadro de debilidad progresiva en hemicuerpo derecho y cefalea subita punzante intensa (1). Estos sintomas habian aparecido la semana previa a la consulta. La RMN cerebral revelo la presencia de una lesion expansiva frontoparietal izquierda con realce anular y edema periferico. La serologia para VIH fue positiva, con un recuento de CD4 de 18 cel/mm3 y una carga viral de 133-400 copias/ml. Se comenzo con tratamiento antirretroviral y empirico para toxoplasmosis. La serologia resulto positiva para Chagas y negativa para toxoplasmosis, VDRL, HCV y HBV. La prueba de antigenemia para criptococo, la deteccion de T. cruzi en sangre y la PCR en liquido cefalorraquideo para toxoplasmosis, virus de Epstein Barr y virus JC resultaron negativas. La tincion con Giemsa en liquido cefalorraquideo (Figura) permitio detectar tripomastigotes de T. cruzi; esto condujo al diagnostico de chagoma cerebral y evito la biopsia cerebral. Se suspendio el tratamiento para toxoplasmosis y se inicio el tratamiento con benznidazol, tras lo cual el paciente tuvo una buena evolucion clinica y radiologica. A todo individuo VIH positivo proveniente de zona endemica que presente lesion cerebral se le debe solicitar serologia para Chagas y la busqueda de T. cruzi, para determinar la presencia de una reactivacion.

Human Cystic and Alveolar Echinococcosis

Opinion statementEchinococcus granulosus causes human cystic echinococcosis, whereas Echinococcus multilocularis produces human alveolar echinococcosis. The latter constitutes a slowly progressive but often fatal disease. Cystic echinococcosis is widely distributed and represents a serious problem in sheep- and cattle-raising areas. Eggs released from gravid proglottids in faeces from definitive hosts may contaminate water, fruits, or weeds, and be eaten by humans or other intermediate hosts where a hydatid cyst develops. Histopathological and microscopic examinations, imaging techniques and serologic tests as well as molecular studies are used in diagnosis. Whenever possible, hydatid cysts should be removed surgically, taking precaution to avoid rupture that could lead to seeding, metastatic proliferation and anaphylactic shock. In cases when surgery is not possible, chemotherapy with albendazole or, alternatively, mebendazole combined with praziquantel is used. The close contact with infected dogs is a risk factor for humans. Prevention includes eliminating infection in definitive hosts—especially domestic dogs—by periodic deworming and preventing them from consuming raw entrails from butchered animals. Introduction of vaccines in sheep has been successful as it remarkably diminishes hydatid cysts, with regard to number and size. However, in spite of the different measures taken, the continuous report of cases in endemic countries shows that those measures are insufficient. Widespread vaccine administration to domestic animals acting as intermediary hosts shows promise in achieving a long-term disease prevention and control. In conclusion, current interventions need to be sustained and combined with effective vaccines.

Hydatidosis of the Central Nervous System in South America

In this chapter, we reviewed the epidemiology of cystic hydatidosis in South America, especially focusing on hydatidosis of the central nervous system. Echinococcus granulosus and E. multilocularis are the most frequent species in humans. Hydatidosis is endemic in several Latin American countries, including Argentina, Bolivia, Brazil, Chile, Peru, and Uruguay. The global occurrence of hydatid cysts of the central nervous system is uniformly low, with a reported incidence of 0.9–2.1 % of all cases of hydatidosis.

Malaria importada en Buenos Aires: diagnóstico de 2 casos

Se presentan 2 casos de malaria importados1 del continente africano que fueron diagnosticados en la Ciudad Autonoma de Buenos Aires. Caso 1: un joven de 36 anos de origen nigeriano concurrio para la consulta al Hospital de Clinicas de la Ciudad de Buenos Aires, por presentar sintomas de fi ebre, dolor de cabeza, malestar general, sudoracion nocturna y fuertes escalofrios. La fi ebre y los escalofrios se presentaban en forma periodica, con intervalos entre 36 y 48 horas. En el examen clinico se observo esplenomegalia. El extendido fi no y la gota gruesa tenidos con colorante de Giemsa revelaron solamente la presencia de elementos parasitarios intraeritrociticos en forma de anillos pequenos. Los globulos rojos no exhibian cambios en cuanto al tamano. En base a estos datos y la historia clinica del paciente, se diagnostico malaria por Plasmodium falciparum. El paciente fue tratado con mefl oquina. Caso 2: un paciente de 30 anos oriundo de Senegal concurrio al Hospital de Clinicas de la Ciudad de Buenos Aires, por presentar fi ebre intermitente de 4 dias de evolucion y fuertes escalofrios. El paciente refi rio haber padecido sintomas similares unos anos antes, los que remitieron luego del tratamiento con artesunato y amodiaquina. El estudio microscopico del extendido fi no y la gota gruesa tenidos con colorante de Giemsa revelo la presencia de globulos rojos agrandados que en su interior presentaban formas ameboides y anulares correspondientes a Plasmodium vivax.