Actualización de la bronquiolitis aguda / Acute bronchiolitis update

La bronquiolitis aguda es una condición respiratoria frecuente en los niños menores de 2 años. Representa la principal causa de hospitalización infantil y se caracteriza por la presencia de sibilancias asociada a signos de una infección respiratoria alta. El agente etiológico más común es el virus respiratorio sincicial. Existe una falta de consenso con respecto a su definición clínica; y por ello, su tratamiento varía en todo el mundo. El diagnóstico es clínico, sin necesidad de emplear laboratorio o imágenes en forma rutinaria. Diversas revisiones han demostrado que los broncodilatadores, adrenalina, corticoides y antibióticos, entre otros, carecen de eficacia por lo que no se sugiere su empleo. El tratamiento sigue siendo de soporte, mediante la administración de oxígeno y manteniendo una adecuada hidratación. Cuando no se logra disminuir el trabajo respiratorio o corregir la hipoxemia se puede utilizar la presión positiva en la vía aérea para prevenir y controlar la insuficiencia respiratoria. Este artículo desarrolla una breve revisión de las principales características clínicas, epidemiológicas, radiológicas, así como algunos de los diferentes tratamientos publicados en las últimas dos décadas.

Acute bronchiolitis is a common respiratory condition in children under 2 years old. It represents the main cause of childhood hospitalization characterized by the presence of wheezing associated with signs of an upper respiratory infection. The most common etiologic agent is respiratory syncytial virus. There is a lack of consensus regarding its clinical definition; and therefore, its treatment varies around the world. Diagnosis is clinical, without the need for routine laboratory or imaging. Various reviews have shown that bronchodilators, epinephrine, corticosteroids, and antibiotics, among others, lack efficacy, so their use is not suggested. Treatment continues to be supportive, by administering oxygen and maintaining adequate hydration. When it is not possible to reduce the work of breathing or correct the hypoxemia, positive airway pressure can be used to prevent and control respiratory failure. This article develops a brief review of the main clinical, epidemiological, and radiological characteristics, as well as some of the different treatments published in the last two decades.

¿Hay una asociación entre deficiencia de vitamina D y riesgo de bronquiolitis y asma bronquial en la infancia?: Una revisión crítica / Is there a relation between vitamin D deficiency and an increased risk for bronchiolitis and bronchial asthma in childhood?: A critical revision

Se revisa críticamente la información científica relacionada con deficiencia de vitamina D (DVD) y riesgo de infecciones respiratorias agudas bajas (IRAB) o asma bronquial en niños. Las IRAB, en especial por virus respiratorio sincicial (VRS) están asociadas a una alta carga de enfermedad. Al no contar aún con una vacuna para ellas, las medidas preventivas y de sostén son las más importantes. El DVD es prevalente en todos los ambientes geográficos, con consecuencias ligadas al metabolismo de calcio y óseo, pero también alteraciones de la inmunidad. Hay evidencia inicial de una asociación entre DVD y mayor riesgo de IRAB, especialmente durante los primeros meses de vida; alelos de algunos polimorfismos del receptor de vitamina D podrían asociarse a un mayor riesgo de IRAB. Este escenario cosmopolita, justifica estudiar el impacto de medidas de suplementación de VD adaptadas a las realidades locales, a la madre durante el embarazo y/o al niño en los primeros meses de vida, que impacten sobre el riesgo de presentar IRAB y asma.

We critically review the information about vitamin D deficiency (VDD) and risk of lower respiratory infections and asthma in children. Acute lower respiratory infections (ALRI), particularly those due to respiratory syncytial virus (RSV) are associated with a high burden of disease. In theabsence of a vaccine for them, prevention and support during illness are important measures to reduce the risk of acquiring the condition or decreasing its severity. VDD has been described as prevalent in all geographical environments; its consequences are linked to calcium and bone metabolism, but also to impaired immunity. Recent evidence of an association between VDD and increased risk of ALRI, especially during the first few months of life has been demonstrated; alleles of some polymorphism of vitamin D receptor may be involved in an increased risk of LRTI. It is justified to study the impact of measures of vitamin D supplementation adapted to local environments, including the appropriate doses to the mother during pregnancy and/or to the child in the first months of life, on the risk of ALRI, or asthma in later ages.

Estado oxidante e antioxidante de crianças com bronquiolite aguda / Oxidative and antioxidative status of children with acute bronchiolitis

OBJETIVO: O estresse oxidativo demonstrou contribuir para a patogênese de doenças pulmonares inflamatórias agudas e crônicas. Nosso objetivo foi avaliar o estado oxidante/antioxidante de crianças com bronquiolite aguda por meio de mensuração da capacidade antioxidante total do plasma, estado oxidante total e índice de estresse oxidativo. MÉTODOS: As crianças com bronquiolite aguda encaminhadas para o Departamento de Emergência Pediátrica do hospital universitário entre janeiro e abril 2012 foram comparadas a controles saudáveis de mesma idade. Os pacientes com bronquiolite aguda tiveram essa doença classificada como leve e moderada. O estado oxidante e antioxidante foi avaliado pela mensuração da capacidade antioxidante total do plasma, estado oxidante total e índice de estresse oxidativo. RESULTADOS: Foram incluídas 31 crianças com bronquiolite aguda com idade de três meses a dois anos e 37 crianças saudáveis. O estado oxidante total (EOT) foi maior em pacientes com bronquiolite aguda do que no grupo de controle (5,16±1,99 µmol H2O2 em comparação a 3,78±1,78 µmol H2O2 [p = 0,004]). A capacidade antioxidante total (CAT) foi significativamente menor em crianças com bronquiolite que no grupo de controle (2,51±0,37 µmol Trolox equivalente/L em comparação a 2,75±0,39 µmol Trolox Eqv/L) (p = 0,013). Os pacientes com bronquiolite moderada apresentaram níveis de EOT mais elevados que os com bronquiolite leve e os do grupo de controle (p = 0,03, p < 0,001). Os pacientes com bronquiolite moderada apresentaram níveis de IEO mais elevados que os do grupo de controle (p = 0,015). O nível de saturação de oxigênio de pacientes com bronquiolite foi inversamente correlacionado ao nível de EOT (r = -0,476, p < 0,05). CONCLUSÃO: O equilíbrio entre os sistemas oxidante e antioxidante é interrompido em crianças com bronquiolite moderada, indicando que o fator de estresse poderá ter um papel na patogênese da doença.

OBJECTIVE: Oxidative stress has been shown to contribute to the pathogenesis of acute and chronic lung inflammatory diseases. This article aimed to evaluate the oxidant/antioxidant status of children with acute bronchiolitis through the measurement of plasma total antioxidant capacity, total oxidant status, and oxidative stress index. METHODS: Children with acute bronchiolitis admitted to the pediatric emergency department of a university hospital between January and April of 2012 were compared with agematched healthy controls. Patients with acute bronchiolitis were classified as mild and moderate bronchiolitis. Oxidative and antioxidative status were assessed by measurement of plasma total antioxidant capacity, total oxidant status, and oxidative stress index. RESULTS: Thirty-one children with acute bronchiolitis aged between 3 months and 2 years, and 39 healthy children were included. Total oxidative status (TOS) was higher in patients with acute bronchiolitis than the control group (5.16±1.99 µmol H2O2 versus 3.78±1.78 µmol H2O2 [p = 0.004]). Total antioxidant capacity (TAC) was lower in children with bronchiolitis than the control group (2.51±0.37 µmol Trolox eqv/L versus 2.75±0.39 µmol Trolox eqv/L [p = 0.013]). Patients with moderate bronchiolitis presented higher TOS levels than those with mild bronchiolitis and the control group (p = 0.03, p < 0.001, respectively). Patients with moderate bronchiolitis had higher oxidative stress index levels than the control group (p = 0.015). Oxygen saturation level of bronchiolitis patients was inversely correlated with TOS (r = -0.476, p < 0.05). CONCLUSION: The balance between oxidant and antioxidant systems is disrupted in children with moderate bronchiolitis, which indicates that this stress factor may have a role in the pathogenesis of the disease.

Infección por metapneumovirus en pacientes internados en un hospital pediátrico / Metapneumovirus infection in patients in a pediatric hospital

La infección respiratoria es un importante motivo de internación en pediatría. Ultimamente se identificó a los Metapneumovirus como agentes etiológicos de infecciones respiratorias. Se estudiaron 897 niños internados a los cuales se les realizó el estudio de detección de virus respiratorios, incluyendo Metapneumovirus, por inmunofluorescencia indirecta entre noviembre y diciembre de 2009. Se detectaron 55 pacientes con muestras positivas para virus respiratorios en secreciones nasofaringeas: 33 de ellas fueron positivas para Metapneumovirus. Se analizaron las características epidemiológicas, clínicas y evolutivas de niños con Metapneumovirus en forma retrospectiva. La edad media fue de 45 meses (r =0 a 204) y el 60% eran mayores de un año. Diecisiete de los mayores de un año (85%) presentaron comorbilidades. La bronquiolitis fue la forma clínica más frecuente en los menores de un año [9 (69%) y 8 (61%)] requirieron oxígeno. Todos tuvieron buena evolución. Conclusiones: Metapneumovirus fue causa de internación en los menores de un año y en los mayores con enfermedad de base. La presentación clínica fue similar a la producida por otros virus. Se observó su predominio sobre otros virus como causa de infección respiratoria entre noviembre y diciembre de 2009.

Respiratory infection is a common cause for hospital admission in children. Recently, the metapneumovirus has been identified as a causative agent of respiratory infection. Between Novem-ber and December 2009, 897 pediatric inpatients were studied for respiratory viruses, including the metapneumovirus, using indirect immunofluorescence techniques. Of all patients, 55 had positive nasopharyngeal samples for respiratory viruses; 33 were positive for the metapneumovirus. The epidemio-logical and clinical features and outcome of the children with metapneumovirus were retrospectively analyzed. Mean age was 45 months (r = 0 to 204) and 60% was older than one year. Seventeen of the children older than one year (85%) presented with comorbidities. Bronchiolitis was the most com-mon clinical presentation in children younger than one year. Nine (69%) and eight (61%) children, respectively, required oxygen therapy. Outcome was good in all patients. Conclu-sions: Metapneumovirus was the cause of hospital admission in children under one year of age and in children older than one year with an underlying disease. Symptoms were similar to those produced by other viruses. Between November and December 2009, the metapneumovirus was more commonly observed than other viruses as a cause of respiratory infection.

Bronquiolite associada à exposição a aroma artificial de manteiga em trabalhadores de uma fábrica de biscoitos no Brasil / Bronchiolitis associated with exposure to artificial butter flavoring in workers at a cookie factory in Brazil

OBJETIVO: Relatar quatro casos de bronquiolite decorrente de exposição a aroma artificial de manteiga em uma fábrica de biscoitos no Brasil. MÉTODOS: Descrevemos os achados clínicos, espirométricos e tomográficos nos quatro pacientes, assim como achados de biópsia pulmonar em um dos pacientes. RESULTADOS: Os quatro pacientes eram homens jovens, não fumantes, e desenvolveram obstrução persistente ao fluxo aéreo (relação VEF1/CVF reduzida e VEF1 de 25-44% do previsto) após 1-3 anos de exposição a diacetil, sem a utilização de equipamentos de proteção individual, em uma fábrica de biscoitos. A TCAR mostrou achados indicativos de bronquiolite. Em um paciente, a biópsia pulmonar cirúrgica mostrou bronquiolite obliterante associada a células gigantes. CONCLUSÕES: A bronquiolite decorrente de exposição a flavorizantes artificiais deve ser considerada em trabalhadores com obstrução ao fluxo aéreo no Brasil.

OBJECTIVE: To report the cases of four patients with bronchiolitis caused by exposure to artificial butter flavoring at a cookie factory in Brazil. METHODS: We described the clinical, tomographic, and spirometric findings in the four patients, as well as the lung biopsy findings in one of the patients. RESULTS: All four patients were young male nonsmokers and developed persistent airflow obstruction (reduced FEV1/FVC ratio and FEV1 at 25-44% of predicted) after 1-3 years of exposure to diacetyl, without the use of personal protective equipment, at a cookie factory. The HRCT findings were indicative of bronchiolitis. In one patient, the surgical lung biopsy revealed bronchiolitis obliterans accompanied by giant cells. CONCLUSIONS: Bronchiolitis resulting from exposure to artificial flavoring agents should be included in the differential diagnosis of airflow obstruction in workers in Brazil.

Risk factors for respiratory syncytial virus [RSV] bronchiolitis in children. a hospital based study

Respiratory syncytial virus [RSV], historically being the major causative agent. RSV causes respiratory disease in young children worldwide and by the age of two years most children have been infected. The aim of this study was to investigate the effect of passive smoking alone and in conjunction with breastfeeding and Crowding index and Family history of atopy in determining the risk of bronchitis in Children under of 5 years of age. We studied 100 consecutive Children aged from [1]day to [60]months [56boys and 44 girls],median age 30 months, who required hospital admission for acute bronchiolitis at the Pediatric Department, Children Welfare teaching hospital, medical city complex-Baghdad. The cases were compared with 100 patients at the same age groups with no history of Bronchilolitis .The following parameters was studied in both groups: Exposure to passive smoking, type of feeding [Breast, Bottle, and Mixed], Family history of atopy, and crowding index. High level of exposure to passive smoking on the other hand significantly increase the risk of having bronchiolitis by [2.3] times compared to those with negative exposure. Breast feeding significantly decrease the risk of having bronchiolitis by 5 times compared to those on mixed and bottle feeding. A positive family history of atopy significantly increase the risk of bronchiolitis by [9.5]times . Subjects with moderately high crowding index [interquartile range]has 6.3 times of having increase the risk of bronchiolitis compared to those of living in uncroweded residence [first quartile crowding index].Highly crowding index [forth quartile]significantly increase the risk by 101 times compared to the those in un crowded [first quartile]residence. Although Smoking, Lack of Breast feeding and family history of atopy are important risk factors for RSV bronchiolitis But Crowding seems to be the most important risks factors for RSV bronchiolitis in this study

Bronquiolitis constrictiva: ¿qué conocemos acerca de esta enfermedad fibrosante de las vías aéreas?

OBJETIVOS: 1. Identificar la bronquiolitis constrictiva como una enfermedad fibrosante a diferencia de la bronquiolitis proliferativa, una condición inflamatoria de las vías aéreas. 2. Describir las causas de la bronquiolitis constrictiva y su asociación a enfermedades sistémicas. 3. Identificar los hallazgos clínicos, radiológicos y fisiológicos de la bronquiolitis constrictiva. 4. Conocer y entender el manejo y tratamiento de la bronquiolitis constrictiva. 5. Describir la evolución clínica de la bronquiolitos constrictiva. La bronquiolitis constrictiva es una enfermedad respiratoria que afecta las pequeñas vías aéreas y es importante reconocerla debido a su naturaleza fibrosante e irreversible. Los términos utilizados en el mundo para describir esta condicion son variables. En esta revisión, el término Bronquiolitis obliterans constrictiva (BOC) será usado para describir este síndrome que se presenta como una condicion fibrótica de las pequeñas vías aéreas. Patología generalmente utiliza el término bronquiolitis constrictiva y lo usará independientemente si hay o no obliteración total de las vías aéreas; clínicamente la enfermedad se manifiesta, especialmente, cuando hay obliteración de las pequeñas vías aéreas.

Enfermedad pulmonar difusa asociada al consumo de tabaco / Smoking related interstitial lung disease: case report

The relationship between cigarette smoke and interstitial lung diseases (ILD) is not clear. Respiratory bronchiolitis (RB), usually found as an incidental histologic abnormality in otherwise asymptomatic smokers, is characterized by the accumulation of cytoplasmic golden-brown-pigmented macrophages within respiratory bronchioles. A small proportion of smokers have a more exaggerated response that, in addition to the bronchiole-centered lesions, provokes interstitial and air spaces inflammation and fibrosis extending to the nearby alveoli. This set of histologic changes is called RB-ILD, and it results in clinical symptoms. Desquamative interstitial pneumonia (DIP) is characterized by panlobular involvement, diffuse mild-to-moderate interstitial fibrosis, and massive alveolar filling with macrophages. It is well known that the histopathologic patterns of RB-IID and DIP may overlap, and that the key features for differentiating these disorders are the distribution and the extent of the lesions: bronchiolocentric in RB-IID and diffuse in DIP. It has been proposed that RB, RB-IID and DIP may be different components of the same histopathologic disease spectrum, representing various degrees of severity of the same process caused by chronic smoking, although this is still controversial. To illustrate the problem, we present the clinical case of a heavy-smoker patient with progressive dyspnea and radiographic pulmonary infiltrates suggesting of smoking related interstitial lung disease.

La enfermedad pulmonar difusa asociada al consumo de tabaco no ha sido claramente definida, la bronquiolitis respiratoria (RB) es un hallazgo morfológico frecuente en fumadores asintomáticos, se caracteriza por la acumulación de macrófagos pigmentados en los bronquiolos respiratorios. Sólo una pequeña proporción de los sujetos fumadores presenta una respuesta inflamatoria exagerada que compromete el intersticio y espacio alveolar, lo cual corresponde a la bronquiolitis respiratoria asociada a enfermedad pulmonar difusa (RBIID), que se manifiesta por disnea de esfuerzos y tos. La neumonía intersticial descamativa (DIP) se caracteriza por compromiso panlobular, fibrosis intersticial discreta e infiltración masiva del espacio aéreo por macrófagos. El patrón histopatológico de RBIID y DIP se pueden sobreponer, siendo los principales elementos diferenciadores entre ambas entidades, la distribución y extensión de las lesiones: compromiso bronquiolo-céntrico en RBIID y difuso en DIP. Se ha planteado que la RB, RBIID y DIP pueden constituir diferentes fases de una misma enfermedad asociada al consumo de tabaco, lo cual aún es motivo de controversia. Con el propósito de ilustrar este problema, se presenta el caso clínico de un paciente fumador que consultó por disnea progresiva, tos e infiltrados pulmonares bilaterales sugerentes de enfermedad pulmonar difusa asociada al tabaquismo.

Etiologia das bronquiolites. (Carta ao Editor) / The etiology of bronchiolitis. (Letter to the Editor)

A bronquiolite é responsável por elevados índices de hospitlização de crianças, em todo o mundo. Nos Estados Unidos, a bronquiolite é a primeira causa de internação de lactentes; no Hospital Universitário da USP é secundada pelas pneumonias. O principal agente etiológico da bronquiolite...

Respiratory syncytial virus infection in patients visiting King Khalid University Hospital

Respiratory syncytial virus [RSV] is a leading cause of lower respiratory tract infections in infants and young children worldwide. The involvement of lower respiratory tract, manifest clinically as bronchiolitis or pneumonia is the hallmark of severe RSV disease. This study aimed to assess the prevalence of RSV among patients visiting King Khalid University Hospital, King Saud University, Riyadh. Nasopharyngeal aspirate samples were obtained from patients with acute respiratory symptoms visiting King Khalid University Hospital in the period between 1999 and 2003. Samples were sent to the virology unit for detection of RSV hntigens using direct immunofluorescence test. 19.3% of the nasopharyngeal aspirate samples were positive for RSV. Most of the cases were in the age group 0-6 months [58.9%], followed by age group > 6- 12 months [19.8%]. Seasonal variation showed that most of the RSV cases were predominant during winter and early spring months. Infections with RSV are a common cause of morbidity and mortality among Saudi patients. A better understanding of the epidemiology of RSV infections may be used for timely, specific antiviral therapy and prophylaxis

Relación entre bronquiolitis aguda con factores climáticos y contaminación ambiental / Association of acute bronchiolitis with climate factors and environmental contamination

BACKGROUND: Annually, acute bronchiolitis (AB) occurrence peaks during winter and is probably associated with air pollution. AIM: To relate the number of ambulatory consultations, emergency and hospital admission due to AB with climatic factors and air pollution. PATIENTS AND METHODS: Patients of less than 1 year old with AB that consulted to outpatient clinics, the emergency room or were admitted to the Pediatrics ward of the Catholic University Hospital, were enrolled. Information about respiratory syncytial virus (RSV) was obtained from the Catholic University Medical Investigation Center. Indices of air pollution such as particulate matters of less than 10 microns/m3 (PM 10), of less than 2.5 microns/m3 (PM 2.5), CO, SO3 and O3 were obtained from the Metropolitan Environmental Service. Temperature, humidity and precipitations were obtained from the Chilean Meteorological Service. RESULTS: Ninety nine consultations in out patient clinics and 442 in emergency rooms were collected (55 per cent male, mean age 4.8 months). One hundred fifty two were admitted (34.4 per cent). Thirty percent of children consulting in emergency rooms were younger than 3 months and 43 per cent of them were hospitalized. The RSV study was made in 307 patients and 52 per cent were positive. There was a higher rate of hospital admissions among RSV positive than RSV negative patients (52.5 and 22 per cent respectively, p < 0.001). No association between environmental variables or air pollution and the number of consultations was observed. Young age and smoking inside the household were the main risk factors for hospital admission due to acute bronchiolitis. CONCLUSIONS: Environmental variables did not influence the number of cases of acute bronchiolitis. Young age and exposure to tobacco smoke were risk factors for hospital admission.

Bacterial coinfections in infants with bronchiolotis

Although bronchiolitis is a viral infection of the lower respiratory tract in children, yet, antibiotics are widely prescribed in the treatment of those patients. This study investigated the frequency of bacterial co-infection in infants with bronchiolitis, in relation to the clinical signs, X-Ray findings and total and differential leukocytic count. The overall aim was to try to find out simple clinical and/or investigation criteria to rationalize antibiotic therapy in such patients. Sixty-nine patients with clinical diagnosis of bronchiolitis [34 boys and 35 girls] with age range of 1 - 15 months, mean 5.09 +/- 2.84 months were included in the study. Bacterial coinfection was diagnosed by culture of sputum obtained by tracheal aspirate done under direct laryngoscopic visualization, using sterile mucous extractor. Bacteria was isolated from 37.6% of the studied children, Staphylococci, pneumococci, beta hemolytic streptococci were the most common invaders. High and prolonged fever, toxic look, wide spread crepitations on chest auscultation, were more frequently encountered in patients with concomitant bacterial infection, and the difference was statistically significant. Radiological picture of wide spread infiltrates and/or consolidation was a characteristic feature of patients with positive bacterial culture 61.4%, compared to 4.6% in those with no bacterial isolates. Meanwhile, higher total leukocytic count was observed in patients with bacterial coinfection [mean 11.7 +/- 3.8] compared to those with negative culture [9.89 +/- 3.1]. Patients with bacterial coinfection required significantly longer duration of in-patients treatment [7.6 '2.9 days] compared to those without [4.7 +/- 1.9]. Among the above mentioned clinical and investigations criteria, X Ray findings showed high specificity [95.3%], positive and negative predictive values [88.8%, and 80.3%], but is less sensitive in diagnosis of bacterial coinfection [61.5%]. The presence of wide spread crepitations is more sensitive [79.9%], carries high negative predictivity [85%], but less specific [79%]. The presence of both together is highly specific [97.6%], but less sensitive and predictive. It was concluded that careful clinical assessment of patients with bronchiolitis can help to identify candidates for antibiotic therapy, particularly so, if radiological facilities are available

Chlamydia trachomatis en las infecciones respiratorias agudas del tracto inferior en menores de 6 meses / Chlamydia trachomatis in low tract acute respiratory infections in infants under 6 months of age

En este trabajo retrospectivo se presentan los resultados de serología para Chlamydia trachomatis, de detección de sus antígenos así como de infecciones mixtas a virus y clamidia en niños menores de 6 meses con neumonía o bronquiolitis internados en hospitales públicos de Buenos Aires. Se estudiaron 297 sueros pertenecientes a dos poblaciones: a) niños con etiología viral y bacteriana negativa y b) niños en los que no se excluyó previamente etiología viral ni bacteriana. Los anticuerpos anti-C. trachomatis (IgG e IgM) se investigaron por enzimoinmunoensayo (EIE), microinmunofluorescencia (MIF) y/o inmunofluorescencia indirecta (IFI). En 145 aspirados nasofaríngeos (ANF) se investigó Virus Sincicial Respiratorio (RSV) y Adenovirus por IFI. En 25 pacientes con diagnóstico de infección reciente por clamidia se determinó antígeno clamidial en el ANF por EIE. Se determinó la presencia de infección reciente por C. trachomatis en el 15 por ciento de los casos (45/297) mediante la detección de IgM específica, seroconversión para IgG en muestras pareadas y/o títulos elevados y estables de IgG. El 29,6 por ciento de los pacientes presentó IgG (88/297). La frecuencia de infección reciente en las dos poblaciones de niños fue similar. En neumonías se registró una frecuencia significativamente mayor de infección reciente por C. trachomatis (24,3 por ciento) que en bronquiolitis (11,6 por ciento) (p<0,007). En el 40 por ciento de los pacientes con infección reciente por C. trachomatis (10/25) se pudo demostrar la presencia de antígeno clamidial en ANF. El 62 por ciento de los niños con infección reciente fueron menores de 2 meses de edad. En el análisis de las historias clínicas no se observaron diferencias significativas entre los niños con infección reciente por C. trachomatis versus los que presentaron diagnóstico negativo. Se detectó RSV en el 37 por ciento de los casos estudiados, Adenovirus en el 4 por ciento e infección mixta RSV-clamidia en el 5,5 por ciento. Estos resultados señalan la importancia en nuestro medio de C. trachomatis en las neumonías y bronquiolitis en menores de 6 meses y sugiere la necesidad de su diagnóstico rápido para instituir el tratamiento específico.

Evaluacion etiologica y clinica de infecciones respiratorias agudas bajas en una poblacion infantil / Etiological and clinical evaluation of low acute respiratory infections in children

Se estudió el agente etiológico viral y los principales parámetros clínicos y epidemiológicos de las infecciones respiratorias agudas bajas (IRAB) en una población de 80 niños menores de 4 años internados con diagnóstico de neumonía, bronquiolitis, neumonitis u otros. En los 33 casos confirmados de etiología viral, que constituyeron el 41,3 por ciento del total, el diagnóstico más frecuente fue la bronquiolitis, en tanto que la neumonía lo fue en aquélios en que no se demostró presencia viral. El 63,8 por ciento de la población estudiada eran menores de 6 meses y el grupo de 2 a 5 meses presentó el más alto porcentaje de casos de etiología viral. Predominó en todo el grupo el Virus Sincicial Respiratorio (RSV) 78,8 por ciento (26 casos), seguido por Adenovirus 9,1 por ciento (3 casos), Influenza 6,1 por ciento (2 casos) y Parainfluenza 3 por ciento (l caso). Hubo sólo l caso de infección por 2 virus (RSV e Influenza A). El pico máximo de incidência fue en el mes de junio (comienzo del invierno). La mayoría de los pacientes 77,5 por ciento (62 casos) permaneció internado menos de 10 días. La mortalidad global fue del 7,5 por ciento. La utilización de la asistencia respiratoria mecánica en las bronquiolitis severas reduce la tasa de mortalidad, en tanto que las neumonías por Adenovirus presentan una evolución tórpida con complicaciones. Se estableció un tratamiento antibiótico en el 61,2 por ciento (49/80) de los pacientes. El 34,7 por ciento (l7/49) de los pacientes tratados tuvo un diagnóstico virológico positivo. La disponibilidad del diagnóstico virológico rápido puede contribuir a la disminución del uso innecesario de los antibióticos.

The pulmonary toxicity of cinnamon dust in rats.

The histopathological effect of a single intratracheal dose of respirable cinnamon dust, cinnamon dust extract, and cellulose dust on the lungs of rats was studied sequentially one, seven days and one month after treatment. Exposure to respirable cinnamon and cellulose dusts resulted in alveobronchiolitis at the end of the first and seventh day, and fibrotic changes by the end of the first month. As the extract of cinnamon dust caused no histopathological alterations, it is assumed that the cellulose content of cinnamon dust was responsible for the histological reactions.

Patología de la pequeña vía aérea / High resolution CT in adult bronchiolitis

Las anormalidades bronquiales pueden ser detectadas por aumento o disminución de la densidad del parénquima pulmonar. Cuando ésta disminuye se manifiesta por la existencia de lesiones de tipo destructivo; enfisema, bullas, quistes, bronquioloectasias, o indirectamente por disminución de la perfusión y atrapamiento aéreo. El aumento de densidad puede ser detectado cuando hay engrosamiento de la pared del bronquiolo, inflamación, fibrosis y obstrucción de la luz. Las enfermedades representantes son: la bronquiolitis obliterante, bronquiolitis obliterante con neumonía en organización, bronquiolitis respiratoria y la panbronquiolitis. La Tomografía Computada con alta resolución es la mejor modalidad de imagen para estudiar el parénquima y la vía aérea pulmonar, a través del conocimiento de la anatomía del lóbulo secundario. Si bien es cierto que muchos de los signos para el diagnóstico son indirectos y poco específicos, poder detectar las lesiones favorece el tratamiento médico y orienta la realización de una biopsia pulmonar que dará el diagnóstico definitivo