Leishmania infantum in wild rodents: reservoirs or just irrelevant incidental hosts?

Wild rodents constitute a very large biomass of potential reservoirs for Leishmania spp. Therefore, an epidemiological study was carried out in a well-known focus of canine leishmaniasis from southern Spain, with the objective of detecting and characterizing Leishmania infantum infection in wild rodents. Blood, liver, spleen, bone marrow, and skin from 37 rodents (24 Apodemus sylvaticus, 9 Rattus rattus, and 4 Mus musculus) were analyzed by optical microscopy, culture, and two different polymerase chain reactions. L. infantum DNA was found in 27% (10 out of 37) of the trapped rodents, in a variety of tissues: bone marrow, spleen, or healthy skin (ear lobe). High prevalences of L. infantum infection were found in the three investigated rodent species. The presence of other trypanosomatids was also evidenced. These rodent species are abundant, widely distributed in Europe, and have a long enough lifespan to overcome the low sandfly activity season. They live in a suitable habitat for sandflies and serve as blood sources for these insects, which can become infected when induced to feed on Leishmania-infected animals. Whether they are reservoirs or just irrelevant incidental hosts, it is clear that the epidemiology of L. infantum is more complex than previously thought, and so is its control. The classic epidemiological cycle dog-sandfly-human is turning into a network of animal species that collaborate with the dog in the maintenance of the parasite under natural conditions and probably showing local differences.

[Utility of chest x-ray like approach to etiology of community acquired pneumonia in children]. / Utilidad de la radiografía de tórax en niños como aproximación a la etiología de neumonía adquirida en la comunidad.

INTRODUCTION: Chest X-ray (CR) utility to predict etiology in community-acquired pneumonia (CAP), in children has been controversial. Nevertheless, some authors propose the use of well standardized radiological patterns. OBJECTIVE: To evaluate usefulness of modified Swischuk's radiological patterns (RaP) to determine probable etiology in children hospitalized with CAP. PATIENTS AND METHODS: Eighty children were studied using 6 standardized RaP. The RaP were blindly and individually analyzed by 9 pneumologists, who registered the results (stage 1). Thereafter, (stage 2) a second evaluation adding clinical information was performed. Then, the patients complementary examinations and clinical evolution were included (stage 3). The reference standard (RS) was generated from a blind consensus. Every result was compared with the RS using Student test. RESULTS: According to RS, children were classified as having a virus-like pneumonia in 63% of cases, bacterial in 13%, mixed in 16%, atypical in 5% and ADV in 3%. The agreement of stage 1 and 2 with RS was 64 and 77%, respectively. Virus and bacterial RaP agreement increased from 66 to 82 % (p < 0.001) and from 82 to 90% (p < 0.05), respectively after incorporating clinical parameters. CONCLUSION: Modified Swischuk's RaP used in association with clinical elements allows a quite satisfactory approach to etiologic diagnosis of CAP.

Utilidad de la radiografía de tórax en niños como aproximación a la etiología de neumonía adquirida en la comunidad / Utility of chest x-ray like approach to etiology of community acquired pneumonia in children

Introduction: Chest X-ray (CR) utility to predict etiology in community-acquired pneumonia (CAP), in children has been controversial. Nevertheless, some authors propose the use of well standardized radiological patterns. Objective: To evaluate usefulness of modified Swischuk's radiological patterns (RaP) to determine probable etiology in children hospitalized with CAP. Patients and Methods: Eighty children were studied using 6 standardized RaP. The RaP were blindly and individually analyzed by 9 pneumologists, who registered the results (stage 1). Thereafter, (stage 2) a second evaluation adding clinical information was performed. Then, the patients complementary examinations and clinical evolution were included (stage 3). The reference standard (RS) was generated from a blind consensus. Every result was compared with the RS using Student test. Results: According to RS, children were classified as having a virus-like pneumonia in 63 percent of cases, bacterial in 13 percent, mixed in 16 percent, atypical in 5 percent and ADV in 3 percent. The agreement of stage 1 and 2 with RS was 64 and 77 percent, respectively. Virus and bacterial RaP agreement increased from 66 to 82 percent (p < 0.001) and from 82 to 90 percent (p < 0.05), respectively after incorporating clinical parameters. Conclusion: Modified Swischuk's RaP used in association with clinical elements allows a quite satisfactory approach to etiologic diagnosis of CAP.

Introducción: La utilidad de la radiografía de tórax.(RT) para establecer etiología en niños con neumonía adquirida en la comunidad (NAC) es cuestionada. Objetivo: Evaluar la utilidad de los patrones radiológicos (PRa) de Swischuk modificados para determinar la probable etiología en niños hospitalizados con NAC. Pacientes y Método: Se estudió 80 niños mediante el uso de seis PRa estandarizados. Se procedió al análisis secuencial por nueve neumólogos; individualmente de manera ciega (etapa 1), se registró el PRa. Posteriormente (etapa 2) se agregó información clínica. En seguida se incluyó exámenes complementarios y la evolución de cada niño (etapa 3). El estándar de referencia (ER) fue generado mediante consenso ciego. Se comparó cada resultado con el ER mediante t de Student. Resultados: Según el ER, las etiologías identificadas fueron: viral (63 por ciento), bacteriana (13 por ciento), mixta (16 por ciento), atípica (5 por ciento) y ADV (3 por ciento). El rendimiento de la etapa 1 y 2 fue 64 y 77 por ciento>, respectivamente. El PRa viral y bacteriano aumentó de 66 a 82 por ciento> (p < 0,001) y de 82 a 90 por ciento (p < 0,05), respectivamente, luego de incorporar elementos clínicos. Conclusión: La utilización de PRa de Swischuk modificados, asociados a elementos clínicos, permitió un adecuado rendimiento como aproximación del diagnóstico etiológico en NAC

Evaluación de la musculatura inspiratoria en niños con antecedentes de Mielomeningocele / Evaluation of inspiratory musculature in children with myelomeningocele

Background: Respiratory musculature function in patients with myelomeningocele (MMC) has not been evaluated sufficiently. Impairment in inspiratory muscles capacity could make patients prone to complications in clinical situations in which the respiratory work is increased. Objective: Evaluate inspiratory muscle function, measured with Maximal Inspiratory Pressure (MTP) in children with MMC. Method: In 13 children with MMC, MIP was obtained according to Black and Hyatt technique, using an aneroid gauge pressure. The results were compared to Szeinberg reference values by t Student, where p < 0.05 was considered significant. Results: The average age was 11.9 +/- 2.8 years and 10 female. Expected MIP average was 112 +/- 20 cmH(2)0, with lower limit of 92 cmH(2)0. The observed Pimax was 62 +/- 23 cmH(2)0, 33 percent less than the inferior limit expected (p < 0.05). Conclusions: These children present a decrease of inspiratory musculature force, making them suceptible to muscle fatigue in pathological conditions, requiring a greater respiratory effort and difficulties in mechanical ventilation weaning. We suggest that a regular study of inspiratory muscles is neccessary in MMC patients, in order to define a respiratory musculature training necessity.

Existe escasa evidencia que evalúe la función muscular respiratoria de niños con antecedente de mielomeningocele (MMC). La disfunción de la musculatura inspiratoria puede facilitar complicaciones respiratorias. Objetivo: Evaluar la función de la musculatura inspiratoria, medida a través de la Presión inspiratoria máxima (Pimax), en ni±os con antecedente de MMC. Pacientes y Métodos: En 13 niños se obtuvo Pimax mediante técnica de Black and Hyatt, utilizando un manómetro aneroide. Los valores obtenidos fueron comparados con los valores de referencia de Szeinberg utilizando t Student, considerando significativos p < 0,05. Resultados: La mediana de edad fue 11 años (rango: 8-18; 10 mujeres). La Pimax promedio esperada fue 112 +/- 20 cmH(2)0 (límite inferior 92 cmH(2)0) mientras la Pimax observada fue 62 +/- 23 cmH(2)0, siendo 33 por ciento menor que el límite inferior del valor esperado (p < 0,05). Discusión: Los niños con antecedente de MMC presentaron disminución de la fuerza de los músculos inspiratorios que los podría hacer más susceptibles a la fatiga muscular en situaciones que impliquen mayor trabajo respiratorio así como dificultades frente a la desconexión al ser sometidos a ventilación mecánica.

Effect of semiannual treatments of ivermectin on the prevalence and intensity of Onchocerca volvulus skin infection, ocular lesions, and infectivity of Simulium ochraceum populations in southern Mexico.

The effect of semiannual ivermectin treatment along with nodulectomy on filarial transmission levels were estimated during the three dry seasons of 1991-1993 in a hyperendemic village in southern Mexico. Parasitologic and ophthalmologic examinations were carried out every six months until five drug treatments were completed. Ivermectin mass treatment with a coverage of approximately 80% had a significant impact (P < 0.05) on the prevalence of skin infection and the mean microfilarial skin density (CMFL), which were reduced 38% and 89%, respectively. A gradual and significant (P < 0.05) decrease in the mean microfilariae number in the anterior chamber of the eye and in corneal opacities was also observed as the CMFL was reduced. After three treatments, these were reduced 84% and 69%, respectively. However, after two years of continuous intervention, no significant differences (P > 0.05) were observed in either the daily mean infective biting density and the daily mean transmission potential. This was probably due to the remaining microfilarial load provided by the untreated resident population and migrant groups. On the whole, our results confirm both the efficacy of ivermectin to alleviate the clinical manifestations of the disease and its minimal impact on Onchocerca volvulus transmission, and indicate the need both to achieve higher levels of drug coverage and to incorporate other measures to stop transmission until a macrofilaricide drug is found.

Brain-stem auditory evoked potentials in human immunodeficiency virus-seropositive patients with and without acquired immunodeficiency syndrome.

Brain-stem auditory evoked potentials were recorded in 35 human immunodeficiency virus (HIV)-seropositive subjects from the Centers for Disease Control groups III and IV, 24 HIV-negative drug abusers, and 62 normal healthy controls. None of the patients had evidence of neurological complications. History of alcohol consumption was an exclusion criterion. The values of central conduction times I-V and III-V showed significant differences between the HIV-seropositive subjects and normal healthy controls, as well as between the HIV-seropositive subjects and HIV-negative drug abusers. Central conduction times I-III showed no differences between groups, except in the left ear of Centers for Disease Control group IV compared with controls. No statistical differences were found in the central conduction times between HIV-negative drug abusers and normal healthy controls. The results suggest a subclinical involvement of the upper brain stem in HIV infection. It could be produced by direct action of the virus on central nervous system structures.

Treatment of ketoacidosis and diabetic coma by continuous intravenous administration of water, glucose, regular insulin and electrolytes.

The therapeutical scheme prescribed for the treatment of ketoacidosis and diabetic coma before the 1970s is quite stereotyped and inflexible in regard to the routes of administration and doses of insulin, as well as the management of dehydration and metabolic acidosis. This paper reports the experience of the Endocrinology Service of the General Hospital of the "La Raza" Medical Center for over 10 years. 35 patients with diabetic ketoacidosis were included in a treatment by continuous intravenous administration of glucose, water, insulin and potassium. These patients were programmed in a 12 hour study. The dose of insulin was estimated at a ratio of 1 IU per 1 gm of excess glucose over 2.0 gm/l. The amount of glucose administered was in ratio to the caloric requirements per kilo of bodyweight of the individual patient. The volume of water was administered on the basis of the degree of dehydration estimated. The potassium was prescribed at a ratio of 20 mEq/l of solution, or more if necessary. The patient's recovery was observed during a period of from 7 to 10 hours, with improvement of the hyperglycemia, dehydration and metabolic acidosis. The method has allowed us to observe the diabetic patient's rapid recovery when he has been in ketoacidosis or coma, without complications such as hypoglycemia. No mortality was observed.

[Administration of equally divided doses of propylthiouracil every two-eight hours in hyperthyroidism]. / Administración de igual dosis de propiltiouracilo fraccionada cada dos y cada ocho horas en el hipertiroidismo.

Serum propylthiouracil semi splitting occurs in 1.1 and 1.65 hours when administered in a single dose. In this work treatment for hyperthyroid patients is described; 350 mg were administered daily in divided doses, every two and eight hours. In group A fifteen patients received 50 mg every two hours from 8:00 to 20:00 hs. and in group B nine patients were administered 100, 100 and 150 mg at 8 hour intervals. The patients were hospitalized the first seven days and during this time circulating triiodothyronine and thyroxine concentrations were measured daily at 8:00 and 20:00 hrs. and then at 8:00 hrs. at days 8, 14, 21 and 28. After almost one week of treatment, in group "A", seven patients (46.6 per cent p 0.05) had normal concentration levels in both hormones. In group "B" only one patient reached normal levels in the first eight days. The administration of propylthiouracil every two hours is a useful procedure to attain the euthyroid state in less time than with other therapeutic patterns without undesirable side effects.