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H Schenone

Publications and source records attributed to H Schenone.

At least 37 records · Page 2Linked to original sources
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[Loxoscelism in Chile. Epidemiologic, clinical and experimental studies].

A panoramic sight of epidemiological, clinical and experimental studies, referring to Loxosceles laeta and loxoscelism, carried out in 1955-1988, in Santiago, Chile is presented. Two-hundred and sixteen cases of loxoscelism were studied. The most relevant features were: 84.3% corresponded to cutaneous loxoscelism (CL) and 15.7% to viscerocutaneous loxoscelism (VCL); 73.6% occurred in hot season; in 86.6% of cases the accident happened in the house, particularly in bedrooms, while the people were sleeping or dressing. The spider was seen in 60.2% of cases and identified in the laboratory as L. laeta in 10.6% of all cases. The sites more frequently bitten were the limbs with 67.6%; a burning-stinging was the most frequent initial symptom. Pain, edema and livedoid plaque, which developed later into a necrotic eschar, were the predominant local manifestations. In VCL, hematuria and hemoglobinuria were constant, while jaundice, fever and sensorial involvement were present in most of the cases. CL patients were parenterally treated with antihistaminic drugs or corticoids, while VCL ones were treated with corticoids by injection. The condition of patients in the last follow up was: complete cure in 75.5%, cure with a scarfed sequela in 8.3%, death in 3.7% (all VCL) and abandonment in 12.5%. Additionally, a series of experimental studies, both in vivo and in vitro, has been performed in order to clarify basic aspects on L. laeta venom and the treatment of loxoscelism.

Adolescent↗
PubMedDate not supplied

Seroepidemiology of human toxoplasmosis in Chile.

A series of already published and unpublished seroepidemiological surveys for toxoplasmosis, carried out in Chile in 1982-1994, is reviewed, expanded and analyzed. The surveys included 76,317 apparently healthy individuals of different ages (0.57% of the country's total population), from 309 urban and rural-periurban localities. Urban groups were integrated by blood donors, delivering mothers and middle grade schoolchildren, while rural-periurban individuals corresponded to unselected family groups. Blood samples were collected in filter paper. The presence of antibodies to Toxoplasma gondii was determined by the indirect hemagglutination test (IHAT), titers > or = 16 were considered positive. The test resulted positive in 28,124 (36.9%) of the surveyed people. Two hundred and six (0.3%) individuals presented IHAT titers > or = 1000, probably corresponding to acute or reactivated infections. A progressive increase of positive IHAT from northern to southern regions of the country was noted, phenomenon probably related to geographical conditions and to a higher production and consumption of different types of meat in the latter regions. It is postulated that ingestion of T gondii cysts by humans is epidemiologically as important as ingestion of oocysts. The result presented stress the epidemiological importance of toxoplasmosis in humans, and warn about eventual implications in immunocompromised patients and in transplacental transmission, organ transplants and transfusions.

Adult↗
PubMedDate not supplied

Congenital Chagas disease of second generation in Santiago, Chile. Report of two cases.

Congenital Chagas disease (CChD) has been reported in different countries, mostly in Latin America. In 1987 a fatal case of CChD of second generation (CChDSG) was published. Within a period of six months--1989-1990--two cases of CChDSG were diagnosed and studied in the city of Santiago. Two premature newborns, sons of two sisters, with moderate liver and spleen enlargement, were found to have positive serology for Chagas disease and xenodiagnoses. The mothers, urban residents all their lives, without antecedents of triatomine bugs contact or blood transfusions, showed positive serology and xenodiagnoses. Their mother (grandmother of the infants), lived 20 years in a Northern rural Chagas disease endemic locality, in a triatomine infested house. Afterwards, she moved to Santiago, where she married and has resided up to now. Serology and xenodiagnoses were also positive. All the Trypanosoma cruzi infected individuals were successfully treated with nifurtimox.

Chagas Disease↗
PubMedDate not supplied

[Cutaneous loxoscelism with edematous predominance].

Loxoscelism is the clinical condition produced by the venom of spiders belonging to the genus Loxosceles. Human cases of loxoscelism have been observed in diverse countries of different continents in temperate and tropical regions. In Chile loxoscelism is caused by Loxosceles laeta, spider with domestic habits. Loxoscelism can be observed into two well definited clinical variants: cutaneous loxoscelism (CL) and systemic or viscerocutaneous loxoscelism (VCL) which occur in around 83.3 and 16.7% cases respectively. Within the universe of CL patients a clinical modality in which necrotic lesion is not present or is insignificant, but presenting a remarkable edema, particularly when the bite is on the face, which has received the name of CL with an edematous predominance (CLEP). In this paper the individual description and the assambled analysis of 10 cases, four males and six females, age ranging from 6 to 68 years, of CLEP are presented. Nine cases occurred in warm periods spring through fall and one in winter. In six cases the accident causing spider was seen and two of these were identified as L. laeta adult females. In all cases the patients went or were transported to emergency medical services 4-24 h after the bite. The predominant initial symptom was a burning stinging sensation at the site of the bite, followed by intensive pain which expanded the neighbour areas concomitantly with the emerging and progressive edema. In four of the nine patients in who the bite was on the face, the edema involved all of it, closed both eyelids and expanded to the neck and upper part of the thorax. In three cases the enormous edema was the only significant clinical manifestation, whereas in the remaining seven conjunctly with the edema, a small violaceous plaque or a blister of serous content gave place to a little livedoid plaque (diameter 0.3-0.8 cm) which evolved to desquamation without leaving any scarring. The edema was characterized by its brilliant rose color, painful and hard which is not accompanied by regional adenopathy. Treatment of the 10 patients depended on the moment in they were seen by us. It consisted on parenteral administration, according to age and weight, of 5-10 mg of chloroprofenpyridamine maleate every 8 hours for be continued every 12-24 hours until the patient was discharged. Parenteral route was preferred in order that it was going to be adequately absorbed. With the beginning of the antihistaminic treatment a clear diminution of pain and edema was obtained, being possible its total disappearance within 4-10 days. CLEP occurs in about 4% of loxoscelism cases, has a benign prognosis and an early response to adequate medical treatment. Without discarding the sensibility factor of the affected individual, there exist the impression that the edema may abort the necrotic process when it dilutes the enzymatic process produced by L.laeta venom. In Chile, the differential diagnosis must be planted with the following clinical entities: bites of hematophagous insects on the face, bee stings, Chagas' disease with facial port of entry and angioneurotic edema.

Adult↗
PubMedDate not supplied

[Epidemiological status of Chagas disease in the endemic area from Region II of Antofagasta].

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.

Adult↗
PubMedDate not supplied

[Longitudinal study, by xenodiagnosis, of parasitemia in patients with chronic Trypanosoma cruzi infection].

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.

Adult↗
PubMedDate not supplied

[Human hydatidosis in Chile. Seroprevalence and estimate of the number of infected people].

Chile is located in the southwestern border of South America. The country is 4,329 km long and 96-342 wide. From north to south it is divided into five marked different biogeographical zones: deserts, steppes, bushes, forests (cattle raising) and austral (sheep raising). Population (June 1999) 15,017,760 (14.6% rural). Human hydatidosis is endemic in Chile. According to Ministry of Health information about 320 cases are registered each year. In order to find out the likely prevalence of human hydatidosis in Chile, a series of serosurveys was carried out in 1988-1997 throughout the total country. By using the indirect hemagglutination reaction and ELISA for hydatidosis (tests with good sensibility and specificity) 60,790 unselected apparently healthy persons: 41,399 from urban areas (16,428 blood donors, 13,894 delivering mothers and 11,077 middle grade schoolchildren) and 19,361 from rural areas--from randomly selected family groupings--were studied. A total individuals 82 (136/100,000) resulted positive: 36 (87/100,000) urban and 46 (241/100,000) rural, being the prevalence higher in rural areas, particularly in the southern austral zone (mean 1068/100,00). These figures agree with those observed in clinical epidemiological studies. In conformity with the present results, in the whole country 17,002 individuals should have hydatidosis: 10,318 urban and 6,784 rural. All these possible infected people, not necessarily should present pathology in the future, as it has been observed in autopsies from unselected individuals, performed at the Medico-Legal Service in Santiago, in whom 71.3% of diagnosed hydatosis with hydatid cysts in many different locations, was an autopsy finding.

Adolescent↗
PubMedDate not supplied

[Epizootic outbreaks of trichinosis in 2 pig farms from the Metropolitan Region of Chile].

In Chile swine trichinosis has presented a progressive decreasing in the last two decades of XX century. T. spiralis pig infection descended from an average of 0.683 per 1000 in 1980-1984 to 0.315 in 1985-1989 and to 0.115 in 1990-1996. In the particular case of Metropolitan Region this decreasing has been more marked: from an average of 0.058 per 1000 in 1990-1994 to 0.003 in 1995-1999. Between the end of June 1999 and middle January 2000 in Metropolitan Region abattoirs T. spiralis was detected in 15 (4.9%) out of 306 swine from two pigsties located in El Monte (E.M.) and Padre Hurtado (P.H.) 45 and 30 km south-west from Santiago. In the same period another four pigs from the same premises were found infected in abattoirs of other regions. During inspection visits it was stated that both pig farms had deficient sanitary conditions. Phototrichinoscopy was positive in three out of five Rattus norvegicus collected in E.M. In pigsty PH the examination of diaphragm samples of 25 dogs and 17 cats resulted negative. In the premises originating T. spirali infected swine the Metropolitan Environmental Health Service Abattoirs Program carries out an epidemiological vigilance consisting in the follow-up of animals destined for slaughtering in order to initiate prophylactic actions oriented to eliminate eventual sources of trichinosis infection for human and rearing pigs.

Abattoirs↗
PubMedDate not supplied

[Parasitology and entomology in the 29th century in Latin American narrative].

In the present review of twelve pieces produced by distinguished 20th century Latin American writers--Jorge Luis Borges from Argentina, Jorge Amado and João Ubaldo Ribeiro from Brazil, José Donoso from Chile, Gabriel García Márquez from Colombia, Alejo Carpentier from Cuba, Miguel Angel Asturias from Guatemala, Octavio Paz from Mexico, Mario Vargas Llosa from Perú, Horacio Quiroga and Mario Benedetti from Uruguay and Arturo Uslar-Pietri from Venezuela--paragraphs or parts of paragraphs in which parasitological or entomological situations of the most varied hues are referred to or described, have been extracted in a selective form. Sometimes in these descriptions appear, local or regional expressions, without ignoring colorful folklore representations. For a easier interpretation these or part of these paragraph sentences have been arranged by thematic similarities. In a varied and kaleidoscopic vision, it will be possible to find protozoiasis (malaria, Chagas disease, leishmaniasis, amebiasis), helminthiases (ascariasis, hydatidosis, trichinosis, schistosomiasis, cysticercosis, onchocerciasis), parasitoses produced by arthropods (pediculosis, scabies, tungiasis, myiasis), passing progressively to hemaphagous arthropods (mosquitoes, gnats, horse flies, bedbugs, ticks), venomous arthropods (Latrodectus spiders, scorpions, wasps, bees), mechanical vectors (flies and cockroaches), culminating with a conjunction of bucolic arthropods (butterflies, crickets, grasshoppers cicadas, ants, centipedes, beetles, glow worms, dragonflies).

Animals↗
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[Environmental contamination with Toxocara sp. eggs in public squares and parks from Santiago, Chile, 1999].

Most of cases of visceral larva migrans syndrome are caused by Toxocara canis larvae. Man acquires the infection by accidental ingestion of ripe eggs of the helminth. In order to find out the frequency of the presence of Toxocara sp. eggs in dog fecal specimens from public places of Santiago city in 1999 july-september a study was carried out in 84 squares and 12 parks from 32 counties. Three fecal samples were collected in each of these places, making a total of 288. Each sample was processed according to a modified Telemann method and three smears of each were microscopically examined. Toxocara sp. eggs were found in 39 (13.5%) fecal specimens. In 28/84 (33.3%) squares and in 8/12 (66.7%) parks these eggs were detected. These results make necessary the control of dogs and cats populations with the aim of reduce the presence of animals without responsible owners. It should be advisable to prevent dogs and cats defecation in public areas grounds, trying to exclude these animals from recreation areas.

Animals↗