Tirza Saavedra

Loxoscelismo en Chile: estudios epidemiológicos, clínicos y experimentales

Se presenta un enfoque panoramico de estudios epidemiologicos, clinicos y experimentales referentes a Loxosceles laeta y loxoscelismo efectuados en 1955-1988 en Santiago, Chile. Se estudiaron 216 casos de loxoscelismo. Los hechos mas relevantes fueron: 52,8% correspondio a mujeres; edad entre 7 meses y 78 anos; 84,3% fue loxoscelismo cutaneo (LO y 15,7% loxoscelismo cutaneo-visceral (LCV); 73,6% sucedio en epoca calurosa; en 86,6% el accidente ocurrio en la vivienda, especialmente en dormitorios, mientras la persona dormia o se vestia. La arana fue vista en 60,2% de los casos e identificada en laboratorio como L. laeta en 17,7% (10,6% de los 216 casos). Los sitios mas frecuen temente afectados fueron las extremidades con 67,6%, lancetazo urente fue el sintoma inicial mas frecuente. Dolor, edema y placa livedoide, la cual posteriormente se transformaria en escara necrotica, fueron las manifestaciones locales predominantes. En LCV hematuria y hemoglobinuria fueron constantes, ictericia, fiebre y compromiso de conciencia se presentaron en la mayoria de los casos. Tratamiento: LC con antihistaminicos o corticoides inyectables, LCV con corti-coides inyectables. La condicion de los pacientes en el ultimo control fue: curacion completa en 75,5%, curacion con secuela cicatrizal en 8,3%, muerte en 3,7% (todos con LCV) y abandono en 12,5%. Adicionalmente, se ha efectuado una serie de estudios experimentales, tanto in vivo como in vitro para esclarecer aspectos basicos sobre el veneno de L. laeta y el tratamiento del loxoscelismo.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 loxosce lism were studied. The most relevant features were: 84.3% corresponded to cutaneous loxosce lism (CD and 15.7% to viscerocutaneous loxos celism (VCD; 73.6% ocurred in hot season; in 86.6% of cases the accident happened in the hou se, particularly in bedrooms, while the people were sleeping or dressing. The spider was seen in 60.2%r of cases and identified in the laboratory as L. laeta in 10.69c 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, we re the predominant local manifestations. In VCL, hematuria and hemoglobinuria were cons tant, while jaundice, fever and sensorial involve ment were present in most of the cases. CL patients were parenterally treated with antihistamine 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.

Benign Tumors and Pseudotumors of the Nail A Novel Application of Sonography

Objective. The purpose of this study was to determine the scope of high‐resolution sonography in the detection of benign tumors and pseudotumors of the nail unit. Methods. We performed a retrospective study of the sonographic findings in 103 consecutive patients with benign tumors and pseudotumors of the nail that were medically derived and confirmed histologically. Statistical analysis (Student t test) was performed comparing clinical and sonographic diagnoses. Results. Common benign tumors and pseudotumors of the nail can be detected on sonography, and they present different sonographic morphologic characteristics. According to origin, the lesions were considered ungual in 73% (n = 75) and periungual in 27% (n = 28) of the cases. Sonography showed their nature (solid or cystic), location, and extension as well as regional blood flow. In 35% of the cases, the use of sonography modified the clinical diagnosis, although the detailed anatomic information provided by sonography was useful in the planning of surgery in all cases. The addition of sonography was significant (P < .001) for the diagnosis of subungual exostosis and granulomas in comparison to clinical diagnosis. Conclusions. Sonography is a noninvasive imaging method that can reliably detect common benign tumors and pseudotumors of the nail and provide precise data about their characteristics. This imaging modality can support diagnosis and surgery and can allow a better definition and improvement of the cosmetic outcome of the treatment.

The role of ultrasound in rheumatic skin and nail lesions: a multi-specialist approach

The skin and nails are commonly involved in rheumatic conditions, both by the primary disease and/or long-term immunosuppressive treatments. These superficial affections may also imply a worsening of the quality of life in patients and cosmetic sequels. The latest advances in ultrasound technology show that skin and nail abnormalities are now recognizable and therefore susceptible to follow-up non-invasively. Thus, an ultrasound examination of these superficial tissues may be an adjunct tool for evaluating the progression and/or severity of rheumatic diseases in their primary or secondary manifestations.

Hidatidosis humana en Chile. Seroprevalencia y estimación del número de personas infectadas

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 (June1999) 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, from 13,894 delivering mothers and 11,077 middle grade school children) 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

Calcinosis cutánea distrófica facial secundaria a acné

Actas Dermosifiliogr. 2009;100:615-34 622 como enfermedad de Bowen y carcinoma espinocelular 5,6, siendo la incidencia mayor en varones con lesiones de larga evolucion localizadas en la cabeza, el cuello y otras areas fotoexpuestas 7. El mecanismo molecular de esta transformacion no esta claro. Diversas teorias involucran las proteinas encargadas de la regulacion del ciclo celular, cuya alteracion provocaria la aparicion de otros tumores. Tambien se han implicado el antigeno carcinoembrionario 8, la hormona del crecimiento 9 y las proteinas p63, bcl-2 y bcl-6 en su etiopatogenia 10,11. Ademas, por todos es conocido el papel del VPH en la aparicion de carcinomas epidermoides. En nuestro caso se detecto la cepa 59 en uno de los bloques enviados. Se trata de una cepa de alto riesgo oncogenico, aunque la concentracion viral en la muestra fue muy baja. Como conclusion, cabe senalar que un rapido crecimiento o transformacion de una queratosis seborreica puede ser un signo de desarrollo de un carcinoma epidermoide. En estos casos se recomienda una adecuada y completa extirpacion de la lesion.

Inmunodiagnóstico de la triquinosis humana

An indirect hemagglutination test (IHAT) and an ELISA test for trichinosis using as antigen a larvae soluble fraction from Trichinella spiralis was carried out for the detection of IgG, IgM and IgA specific antibodies in 113 serum samples from patients confirmed or suspected to have trichinosis by strong clinical and epidemiological evidences (Group I). The same tests were also performed on 110 serum samples corresponding to patients without strong evidences of having trichinosis (Group II). In Group I the corresponding sensitivities for RHAI, ELISA IgG, ELISA IgM, ELISA IgA were: 82.3-85.8-88.5 and 88.5% respectively. Seventeen patients were tested again a week after the first analysis (10 of them corresponded to negative ones), increasing the positivity: 23.5-100.0;35.3-100.0;41.2-100.0 and 41.2-100.0% for RHAI, ELISA IgG, ELISA IgM and ELISA IgA, respectively. Other two patients were followed-up for 5 years. IHAT and ELISA IgG remained positive, whereas ELISA IgM and ELISA IgA were constantly negative betweeen 17 and 32 months in one case, and between 48 and 60 months in the other (this last one had presented a severe clinic disease). In the group II, four patients were positive with IHAT, however only one for ELISA IgA, the latter also presented ELISA IgM near the cut off. The use of ELISA IgG, ELSIA IgM and ELISA IgA in the immunodiagnosis of trichinosis is discussed.