Staphylococcus aureus y Alergias. ¿Mito o Realidad?

During the past few years, there have been several studies regarding the connection between bacterial infections and the development of allergic episodes. Staphylococcus aureus has gained a leading role during the process of finding this association. Investigations have been made that relate S. aureus with common pathologies in allergic patients, among them Atopic Dermatitis, Rhinitis, Sinusitis, Conjuntivitis and Asthma. Results demonstrate the presence of this bacterium in patients with these pathologies and typical elements of the immune response related to atopic disorders. Other factors that can take part in this association are: allergic genotype, state of nasal carrier of this microorganism, the microbiological and immunological characteristics of the bacterium and the response at the time it enters the organism. The role that S. aureus plays in the worsening of the allergic episode is clearly demonstrated in different studies, however, there is not an antigen which by itself causes this connection, because the phenomenon is produced by several determinants of pathogenicity of this bacterium (toxins mainly), that later aggravate hypersensitivity states. In addition, the allergic genotype determines the predominant deviation of the immune answer to the TH2 type, chronic and exaggerated, that contributes to the aggravation of these pathologies. After making an extensive bibliographical revision, there is clearly a link between S. aureus like an aggravating factor of allergic pathologies, especially in the case of nasal carriers of this microorganism.Durante los últimos años se ha estudiado a nivel mundial la relación entre infecciones bacterianas y el desarrollo de cuadros alérgicos. Siguiendo esta línea investigativa, llevamos a cabo una revisión bibliográfica que tuvo como objetivos los siguientes: determinar la posible relación entre ciertos procesos alérgicos y Staphylococcus aureus, describir los procesos inmunopatológicos mediante los cuales puede crearse dicha relación, establecer el papel determinante de la condición deportador nasal de S. aureus en la exacerbación de alergias en individuos atópicos y por último, construir un modelo teórico que explique la posible relación entre esta bacteria y ciertas alergias La posible relación entre la presencia de S. aureus y patologías comunes en pacientes atópicos, tales como Dermatitis atópica, Rinitis, Sinusitis, Conjuntivitis y Asma se encuentra determinada por múltiples factores, como lo son: la existencia de un genotipo alérgico en el individuo que desvía la respuesta inmunitaria al tipo TH2, de naturaleza crónica; las características microbiológicas propias de esta bacteria, capaces de producir una respuesta inmunitaria significativa una vez que ingresa al organismo y con especial importancia se encuentra el estado de portador nasal de S. aureus como denominador común en pacientes que padecen patologías atópicas. De este modo, surge la hipótesis de la influencia que ejerce la presencia de S. aureus en la cavidad nasal del paciente sobre la reacción de hipersensibilidad, aún sin que el individuo sea infectado por dicha bacteria. Los resultados obtenidos de la bibliografía demuestran una clara evidencia del rol que juega S. aureus en el agravamiento del cuadro alérgico, no obstante, no ha sido posible determinar la existencia de un único antígeno como causante de esta relación, por el contrario, un conjunto de determinantes de patogenicidad de dicha bacteria (superantígenos principalmente), se han encontrado como responsables de la exacerbación de los estados de hipersensibilidad

Staphylococcus aureus y alergias. ¿Mito o realidad?

Durante los últimos años se ha estudiado a nivel mundial la relación entre infecciones bacterianas y el desarrollo de cuadros alérgicos. Siguiendo esta línea investigativa, llevamos a cabo una revisión bibliográfica que tuvo como objetivos los siguientes: determinar la posible relación entre ciertos procesos alérgicos y Staphylococcus aureus, describir los procesos inmunopatológicos mediante los cuales puede crearse dicha relación, establecer el papel determinante de la condición de portador nasal de S. aureus en la exacerbación de alergias en individuos atópicos y por último, construir un modelo teórico que explique la posible relación entre esta bacteria y ciertas alergias La posible relación entre la presencia de S. aureus y patologías comunes en pacientes atópicos, tales como Dermatitis atópica, Rinitis, Sinusitis, Conjuntivitis y Asma se encuentra determinada por múltiples factores, como lo son: la existencia de un genotipo alérgico en el individuo que desvía la respuesta inmunitaria al tipo TH2, de naturaleza crónica; las características microbiológicas propias de esta bacteria, capaces de producir una respuesta inmunitaria significativa una vez que ingresa al organismo y con especial importancia se encuentra el estado de portador nasal de S. aureus como denominador común en pacientes que padecen patologías atópicas. De este modo, surge la hipótesis de la influencia que ejerce la presencia de S. aureus en la cavidad nasal del paciente sobre la reacción de hipersensibilidad, aún sin que el individuo sea infectado por dicha bacteria. Los resultados obtenidos de la bibliografía demuestran una clara evidencia del rol que juega S. aureus en el agravamiento del cuadro alérgico, no obstante, no ha sido posible determinar la existencia de un único antígeno como causante de esta relación, por el contrario, un conjunto de determinantes de patogenicidad de dicha bacteria (superantígenos principalmente), se han encontrado como responsables de la exacerbación de los estados de hipersensibilidad.TitleStaphylococcus aureus and allergic disease. Mith or reality ?AbstractDuring the past few years, there have been several studies regarding the connection between bacterial infections and the development of allergic episodes. Staphylococcus aureus has gained a leading role during the process of finding this association. Investigations have been made that relate S. aureus with common pathologies in allergic patients, among them Atopic Dermatitis, Rhinitis, Sinusitis, Conjuntivitis and Asthma. Results demonstrate the presence of this bacterium in patients with these pathologies and typical elements of the immune response related to atopic disorders. Other factors that can take part in this association are: allergic genotype, state of nasal carrier of this microorganism, the microbiological and immunological characteristics of the bacterium and the response at the time it enters the organism. The role that S. aureus plays in the worsening of the allergic episode is clearly demonstrated in different studies, however, there is not an antigen which by itself causes this connection, because the phenomenon is produced by several determinants of pathogenicity of this bacterium (toxins mainly), that later aggravate hypersensitivity states. In addition, the allergic genotype determines the predominant deviation of the immune answer to the TH2 type, chronic and exaggerated, that contributes to the aggravation of these pathologies. After making an extensive bibliographical revision, there is clearly a link between S. aureus like an aggravating factor of allergic pathologies, especially in the case of nasal carriers of this microorganism

IgA Nephropathy in Elderly Patients.

Some studies suggest that the incidence of IgA nephropathy is increasing in older adults, but there is a lack of information about the epidemiology and behavior of the disease in that age group. In this retrospective multicentric study, we analyzed the incidence, forms of presentation, clinical and histologic characteristics, treatments received, and outcomes in a cohort of 151 patients ≥65 years old with biopsy-proven IgA nephropathy diagnosed between 1990 and 2015. The main outcome was a composite end point of kidney replacement therapy or death before kidney replacement therapy. We found a significant increase in the diagnosis of IgA nephropathy over time from six patients in 1990-1995 to 62 in 2011-2015 (P value for trend =0.03). After asymptomatic urinary abnormalities (84 patients; 55%), AKI was the most common form of presentation (61 patients; 40%). Within the latter, 53 (86%) patients presented with hematuria-related AKI (gross hematuria and tubular necrosis associated with erythrocyte casts as the most important lesions in kidney biopsy), and eight patients presented with crescentic IgA nephropathy. Six (4%) patients presented with nephrotic syndrome. Among hematuria-related AKI, 18 (34%) patients were receiving oral anticoagulants, and this proportion rose to 42% among the 34 patients older than 72 years old who presented with hematuria-related AKI. For the whole cohort, survival rates without the composite end point were 74%, 48%, and 26% at 1, 2, and 5 years, respectively. Age, serum creatinine at presentation, and the degree of interstitial fibrosis in kidney biopsy were risk factors significantly associated with the outcome, whereas treatment with renin-angiotensin-aldosterone blockers was associated with a lower risk. Immunosuppressive treatments were not significantly associated with the outcome. The diagnosis of IgA nephropathy among older adults in Spain has progressively increased in recent years, and anticoagulant therapy may be partially responsible for this trend. Prognosis was poor. This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2019_07_16_CJASNPodcast_19_08_.mp3

IgA Nephropathy in Elderly Patients

Some studies suggest that the incidence of IgA nephropathy is increasing in older adults, but there is a lack of information about the epidemiology and behavior of the disease in that age group. In this retrospective multicentric study, we analyzed the incidence, forms of presentation, clinical and histologic characteristics, treatments received, and outcomes in a cohort of 151 patients ≥65 years old with biopsy-proven IgA nephropathy diagnosed between 1990 and 2015. The main outcome was a composite end point of kidney replacement therapy or death before kidney replacement therapy. We found a significant increase in the diagnosis of IgA nephropathy over time from six patients in 1990-1995 to 62 in 2011-2015 (P value for trend =0.03). After asymptomatic urinary abnormalities (84 patients; 55%), AKI was the most common form of presentation (61 patients; 40%). Within the latter, 53 (86%) patients presented with hematuria-related AKI (gross hematuria and tubular necrosis associated with erythrocyte casts as the most important lesions in kidney biopsy), and eight patients presented with crescentic IgA nephropathy. Six (4%) patients presented with nephrotic syndrome. Among hematuria-related AKI, 18 (34%) patients were receiving oral anticoagulants, and this proportion rose to 42% among the 34 patients older than 72 years old who presented with hematuria-related AKI. For the whole cohort, survival rates without the composite end point were 74%, 48%, and 26% at 1, 2, and 5 years, respectively. Age, serum creatinine at presentation, and the degree of interstitial fibrosis in kidney biopsy were risk factors significantly associated with the outcome, whereas treatment with renin-angiotensin-aldosterone blockers was associated with a lower risk. Immunosuppressive treatments were not significantly associated with the outcome. The diagnosis of IgA nephropathy among older adults in Spain has progressively increased in recent years, and anticoagulant therapy may be partially responsible for this trend. Prognosis was poor. This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2019_07_16_CJASNPodcast_19_08_.mp3