Boletin chileno de parasitologia最新文献

A serological survey was carried out in Osorno X Region, Chile (40 degrees 21'-40 degrees 46' South lat, and 73 degrees 26' -72 degrees-46' West long.). An indirect hemagglutination test (IHAT) for toxoplasmosis was performed to 305 persons--160 blood donors and 145 with sexually transmitted disease (STD). The age of the surveyed persons (167 males and 138 females) varied between 10 and 72 years. IHAT titers > 16 were considered as positive. The general prevalence was 20.3%--21.2% in blood donors and 19.3% in persons with some STD--with no differences between males and females. However, significant differences between males and females with STD were found (35.6% and 8.1% respectively). No differences between urban and rural inhabitants were found with a slight higher prevalence in the urban ones. No antibodies against Toxoplasma gondii were detected in six AIDS patients. The importance of performing toxoplasmosis immunodiagnosis and individual prophylaxis to avoid the infection in high risk group are recommended.

Formalin preserved fecal samples from 6,058 and 5,863 outpatients were examined for intestinal parasites during 1995 and 1996 respectively. Prevalence rates of infections by intestinal protozoa in both years were similar. By age group (0-9, 10-19 and > 20 years old) Blastocystis hominis was observed in 18.6-19.3, 37.0-31.1 and 25.3-25.4% in 1995-1996 respectively. Prevalence of Giardia intestinalis infections decreased from 16.6-17.4% in the 0-9 year-old children group to 4.1-4.5% in patients over 20 years. Overall percentages of infection by Entamoeba histolytica varied between 4.2 and 10.9. Rates of infections by G. intestinalis, E. histolytica, and Entamoeba coli observed during rainy-cold months (april-september) of the year versus drywarmy period (october-march) were the same. On the contrary, more cases of B. hominis infection 25.8% versus 18.2% (this difference being statistically significant, p > 0.001) were observed during rainy-cold months of the year.

Balantidium coli is the etiologic agent of balantidiasis, an infrequent zoonose of worldwide distribution. The objective of the present study was to determine the clinical and epidemiological aspects of balantidiasis in a rural community in the Bolivar State in Venezuela. Fifty persons and 12 pigs were evaluated. Fecal samples were analyzed by direct examination and by the methods of Faust and Willis. The global rate of intestinal parasitoses detected was 88.0% for the human population and 83.3% for the pigs. The prevalence of human and porcine balantidiais was 12.0% (6/50) and 33.3% (4/12), respectively. The disease was only detected in children, all of them with multiple parasites and with clinical manifestations. Deficient environmental sanitation, absence of basic services in the dwellings, low socioeconomic level, and the presence of pigs infected with B. coli are the factors that explain and maintain the conditions favorable to the transmission of balantidiasis in the population studied.

A 2-5 years follow-up of parasitemia, by the use of xenodiagnosis (XD) was carried out in nine patients with chronic T. cruzi infection who proceeded from chagasic endemic areas of Chile. The patients (mean age 55 years) were hospitalized in the chronic section of a psychiatry institution sited in a permanent triatomines free urban area. Clinical examination, X-rays images (cardiovascular, esophagus and colon) and electrocardiogram resulted normal in all the patients. Basic study unit of parasitemia was a XD box which contained 7 nymphs III of Triatoma infestans which was used in a serial XD consisting in the simultaneous application of a pair of boxes a day during three consecutive days, making a total of six boxes (42 nymphs). The minimal time of duration of infection (M.D.I.) for each patient was estimated that this was adquired close to hospitalization. The M.D.I. varied between 6 and 45 years. The global positivity of XD boxes ranged between 6.3 and 84.7%, being in three patients lower than 12% and in six patients higher than 52%. In considering the yield of XD it is important to stress that during all the study of the nine patients with chronic chagasic infection 1282 XD boxes were applied resulting positive 582 (45.4%). At the end of the follow-up all patients received specific treatment for chagasic infection with nifurtimox at the daily dose of 10 mg/kg of body weight during 60 days. According to the result, two main conclusions arise: 1.--Serial XD has a high efficiency for detecting, evaluate and evolve parasitemia in patients with chronic chagasic infection. 2.--Parasitemia may present low, medium or high levels in different individuals and has a variable and fluctuating character.

Cucullanus pinnai and Spinitectus jamundensis are cited parasitizing three freshwater fish species: Pimelodus albicans, Leporinus obtusidens and Prochilodus lineatus, captured in Termas de Río Hondo pond, province of Santiago del Estero, Argentina, in 1992 and 1995. The three fish species were parasited by S. jamundensis, but C. pinnai was found only in P. albicans and L. obtusidens. Morphologic and morphometric parasitological studies were carried out. The specimens described were drawned. In addition, the following parasitic infection indexes were calculated: prevalence, mean and maximum intensity. The two nematode species identified are described for the first time in Argentina and increased the host range cited for the parasite species studied in this work.

During 1997 a seroepidemiological study on Chagas' disease was carried out in 18 localities of three provinces (Tocopilla, El Loa and Antofagasta) of Region II (20 degrees 56'-26 degrees South Lat.; 70 degrees 38'-67 degrees West Long.), in order to assess the impact of the control program against Triatoma infestans launched in 1988, based on insecticide spraying of dwellings. By means of ELISA and an indirect hemagglutination test for Chagas' disease blood samples from 1,034 children under 10 years of age were examined, arising a 0.5% (3 cases) positivity. Test resulted positive in 2 (0.9%) children from the locality of San Pedro de Atacama and 1 (0.4%) from Calama city, all in the age group 6-10 year-old. However, none of their dwellings were found infested with T. infestants. These results indicate that the control program has a good possibility to prevent new human infections. It is advisable to continue the seroepidemiological and entomological vigilance and remark the necessity of increasing the effort in the study of transmission through other routes, to adopt or reinforce the pertinent preventive measures.

A 24-year-old woman 2-3 months after a normal parturation presented geophagy. Due to hypermenorrhea she consulted a gynecologist and in a hemogram a 57% (6,893 x mm3) hypereosinophilia was detected. A chest TAC showed bilateral pulmonary nodules. The following tests resulted positive: ELISA IgG for toxocariasis 1:1000, isohemagglutinins anti A 1:2048 and anti B 1:512. The patient was treated with albendazole and prednisone during 10 days. One month after treatment eosinophilia decreased to 2.590 x mm3 and ELISA IgG for toxocariasis descended to 1:128. Different aspects of human toxocariasis are commented. When hypereosinophia is observed in adult patients, toxocariasis must be checked.

Echinococcosis is an endemic zoonosis in the south of Chile, so we have the opportunity to treat many patients especially the liver location which is the most common situation of this disease. Hepatic hydatid cyst presents its own morbidity and mortality due its complications and associated with surgical procedures. Morbidity has rates between 11 and 86% and is related with previous surgical interventions, cysts complications, the necessity of perform additional procedures during surgery and the treatment of other disease locations. Mortality by otherwise has rates below 5%. But both, morbidity and mortality persist high in spite of technological advances and therapeutical improvement. The surgical treatment of hepatic hydatidosis can be divided in four phases: surgical area isolation, cysts evacuation, treatment of cyst complications (biliary tract rupture, hepatothoracic transit, etc.), and residual cavity treatment. For each one exist different alternatives. On the other hand, hydatid cyst surgery can be classified in conservative and resective procedures. In the first group we consider marsupialization, cystostomy, Knowsly or Posadas operation and cystojejunostomy. In the resective group we include pericystectomy, partial or subtotal cystectomy and the different types of hepatectomies. Finally, some other surgical procedures are under evaluation. These include the laparoscopic approach of liver echinoccosis with few studies in the field, but with hopeful results.

The prevalence of intestinal parasitsm in nursery schools from Ciego de Avila province was annually avaluated during 1989-1993. The percentage of infected children ranged from 16.6% to 31.6%. An increase of frequence of infection was observed from 1991. Protozoa were more predominant than helminths. In the whole five-year period studied Giardia intestinalis had a higher prevalence (19.6%) followed by Entamoeba histolytica (3.0%). The nematode most frequently found was Trichuris trichiura (0.5%).