RESUMEN
The spectrum of pulmonary diseases that can affect human immunodeficiency virus (HIV)-infected patients is wide and includes both HIV and non-HIV-related conditions. Opportunistic infections and neoplasms remain a major concern even in the current era of combination antiretroviral therapy. Although these diseases have characteristic clinical and radiological features, there can be considerable variation in these depending on the patient's CD4 lymphocyte count. The patient's history, physical examination, CD4 count and chest radiograph features must be considered in establishing an appropriate diagnostic algorithm. In this article, we propose different diagnostic approaches HIV infected to patients with respiratory symptoms depending on their clinico-radiological pattern.
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Técnicas de Diagnóstico del Sistema Respiratorio , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/etiología , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Algoritmos , Antirretrovirales/uso terapéutico , Recuento de Linfocito CD4 , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/fisiología , Humanos , Enfermedades Pulmonares/inmunología , Neumonía por Pneumocystis/diagnóstico por imagen , Neumonía por Pneumocystis/tratamiento farmacológico , Radiografía TorácicaRESUMEN
The Lurbach karst system (Styria, Austria) is drained by two major springs and replenished by both autogenic recharge from the karst massif itself and a sinking stream that originates in low permeable schists (allogenic recharge). Detailed data from two events recorded during a tracer experiment in 2008 demonstrate that an overflow from one of the sub-catchments to the other is activated if the discharge of the main spring exceeds a certain threshold. Time series analysis (autocorrelation and cross-correlation) was applied to examine to what extent the various available methods support the identification of the transient inter-catchment flow observed in this binary karst system. As inter-catchment flow is found to be intermittent, the evaluation was focused on single events. In order to support the interpretation of the results from the time series analysis a simplified groundwater flow model was built using MODFLOW. The groundwater model is based on the current conceptual understanding of the karst system and represents a synthetic karst aquifer for which the same methods were applied. Using the wetting capability package of MODFLOW, the model simulated an overflow similar to what has been observed during the tracer experiment. Various intensities of allogenic recharge were employed to generate synthetic discharge data for the time series analysis. In addition, geometric and hydraulic properties of the karst system were varied in several model scenarios. This approach helps to identify effects of allogenic recharge and aquifer properties in the results from the time series analysis. Comparing the results from the time series analysis of the observed data with those of the synthetic data a good agreement was found. For instance, the cross-correlograms show similar patterns with respect to time lags and maximum cross-correlation coefficients if appropriate hydraulic parameters are assigned to the groundwater model. The comparable behaviors of the real and the synthetic system allow to deduce that similar aquifer properties are relevant in both systems. In particular, the heterogeneity of aquifer parameters appears to be a controlling factor. Moreover, the location of the overflow connecting the sub-catchments of the two springs is found to be of primary importance, regarding the occurrence of inter-catchment flow. This further supports our current understanding of an overflow zone located in the upper part of the Lurbach karst aquifer. Thus, time series analysis of single events can potentially be used to characterize transient inter-catchment flow behavior of karst systems.
RESUMEN
During the last 30 years pulmonary involvement has played a major role in the history of HIV infection. Initially, the unexplained occurrence of pneumocystis revealed the emergence of AIDS and the suspicion of its African origin. Before the era of triple therapy the natural history of AIDS was dominated by the occurrence of repeated lung infections and respiratory physicians were at the forefront of their diagnosis, treatment and prophylaxis. With the provision of antiretroviral therapy (ART), the natural history of AIDS has been transformed in those patients who benefit from it. In addition to paradoxical reactions observed following the introduction of ART, the pulmonologist is also facing a chronic stage of controlled HIV infection, and unexpected events, the incidence of which increases with time: pulmonary arterial hypertension and lung cancer certainly, COPD and fibrosis perhaps but this story remains to be written.
Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/etiología , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/etiología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Antirretrovirales/uso terapéutico , Quimioprevención , Infecciones por VIH/diagnóstico , Infecciones por VIH/terapia , VIH-1 , Humanos , Enfermedades Pulmonares/prevención & control , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/prevención & controlRESUMEN
BACKGROUND: The emergence of novel A(H1N1)pdm2009 virus threatened to lead to frequent severe manifestations. OBJECTIVES: To describe the clinical, virological, and biological characteristics of the disease and identify the factors associated with severe presentations. STUDY DESIGN: This prospective multicenter study recruited consecutive hospitalized patients with confirmed A(H1N1)pdm2009 disease. Clinical, virological and biological assessments were carried out at inclusion and 30 days post-inclusion. Disease manifestations were assessed by an adjudication committee using pre-identified definitions of complications and severity scores. RESULTS: The study analyzed from November 30th, 2009 to February 8th, 2010, 40 hospitalized patients, 21 children and 19 adults. Eighteen (45%) were considered to have severe presentations. Except age, main characteristics in children and adults did not differ. The majority (18/21) of children and all adults had a respiratory presentation; extra-respiratory manifestations tended to be more frequent in children (12 vs. 6, P=0.10). Two children against 5 adults presented acute respiratory distress syndrome (ARDS, P=0.23), but more children suffered respiratory failure (7 vs. 1, P=0.046) without ARDS. At day 30, one death had occurred in each group. The main factor associated with non-severe presentation was an early (<48 h) implementation of oseltamivir treatment (P=0.038). CONCLUSIONS: Although the study failed to achieve its main objective, due mainly to the difficulty of carrying a study of this nature in the midst of a pandemic, it allowed the description of a panel of unusual and complicated forms and confirmed the added value of early oseltamivir treatment in limiting severity in hospitalized children and adults.
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Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/epidemiología , Gripe Humana/patología , Índice de Severidad de la Enfermedad , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Niño , Preescolar , Femenino , Francia , Hospitalización , Humanos , Lactante , Recién Nacido , Gripe Humana/complicaciones , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Oseltamivir/uso terapéutico , Estudios Prospectivos , Factores de Riesgo , Adulto JovenRESUMEN
A prospective study was carried out in two tertiary hospitals in Dakar to determine the main causes of sputum acid-fast bacillus (AFB) smear-negative pneumonia in HIV-infected patients. All clinical and microbiological records were reviewed by experts. Seventy patients were finally enrolled. Most of them were hospitalized at an advanced stage of AIDS. The median CD4 cell count was 62/mm(3) and the median body mass index (BMC) was 18 kg/m(2). Thirty-one patients (44 %) were known as seropositive for HIV infection prior to admission. Radiological opacities were localized in 70 % of patients and diffuse in 21 %. Fiberoptic bronchoscopy was performed in 50 patients (71 %). A definite or probable diagnosis was obtained in 55 patients (79 %). Bacterial pneumonia (usually due to Enterobacteriaceae and Pseudomonas aeruginosa), tuberculosis, Pneumocystis pneumoniae and other causes (Kaposi's sarcoma, atypical mycobacteria) were diagnosed in 67 %, 24 %, 5 %, and 13 % of these patients respectively. In conclusion, pneumonia of bacterial origin and tuberculosis can be incriminated in the majority of cases of AFB negative pneumonia observed in HIV patients in Dakar.
Asunto(s)
Infecciones por VIH/complicaciones , Hospitalización , Neumonía Bacteriana/microbiología , Árboles de Decisión , Humanos , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/etiología , Neumonía Bacteriana/terapia , Estudios Prospectivos , SenegalRESUMEN
BACKGROUND: Pooled analysis of the TORO comparative clinical trial data sets showed a significantly higher incidence rate (IR) of bacterial pneumonia (BP) among patients treated with enfuvirtide-containing combination antiretroviral therapy (ENF-cART) than in those treated with other cART regimens. OBJECTIVES: To examine the possible impact of ENF-cART on the risk of BP. METHODS: From the French Hospital Database on HIV, we selected two groups of patients among cART-treated patients who were prescribed a new cART regimen during the period 2001-2006, when their CD4 counts were <350 cells/mm(3). The ENF-cART and cART groups consisted of 1220 and 9374 patients, respectively. Poisson regression models were used to quantify the relationship between ENF-cART therapy and the risk of BP. RESULTS: At baseline the median CD4 counts were 100 and 211 cells/mm(3) and the median plasma viral load (pVL) values were 60 276 and 2702 copies/mL in the ENF-cART and cART groups, respectively. The respective BP IRs were 0.65 [95% confidence interval (CI) 0.25-1.06] and 0.31 (95% CI 0.25-0.38) cases per 100 person-years. After adjustment for age, the HIV transmission group, the time period, co-trimoxazole prophylaxis, and stratified CD4 cell counts and pVL values, we found that the BP risk ratio was not increased by enfuvirtide treatment (relative rate 1.39; 95% CI 0.46-4.13). In contrast, lower CD4 cell counts and higher pVL values were significantly associated with a higher risk of BP. CONCLUSIONS: ENF-cART is not associated with a significantly higher risk of BP than other cART regimens, although the value of the adjusted risk and the upper limit of the CI do not allow us to exclude a small increased risk.
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Fármacos Anti-VIH/efectos adversos , Terapia Antirretroviral Altamente Activa/efectos adversos , Proteína gp41 de Envoltorio del VIH/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Fragmentos de Péptidos/efectos adversos , Neumonía Bacteriana/inducido químicamente , Adulto , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Enfuvirtida , Femenino , Francia , Proteína gp41 de Envoltorio del VIH/uso terapéutico , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/uso terapéutico , Neumonía Bacteriana/epidemiología , Factores de RiesgoRESUMEN
Diffuse alveolar haemorrhage (DAH) is a feature of several immune and nonimmune disorders. Reported prognosis is poor, with in-hospital mortality ranging from 20% to 100%. Early identification of prognostic factors may be useful in the initiation of appropriate treatment. We retrospectively analysed the charts of all patients referred to a university hospital for DAH between 1980 and 2008. Variables associated with in-hospital and long-term mortality were determined using a logistic regression model and the Kaplan-Meier method, respectively. Immunosuppressed patients were excluded. Overall, 97 patients were included in the study. In-hospital mortality was 24.7%. Factors associated with in-hospital mortality were shock (OR 77.5, 95% CI 8.9-677.2), glomerular filtration rate <60 mL x min(-1) (OR 11.2, 95% CI 1.8-68.4) and plasmatic lactate dehydrogenase level more than twice the normal value (OR 12.1, 95% CI 1.7-84.3). Mortality among discharged patients was 16.4% with a median follow-up duration of 34 months. Factors associated with increased long-term mortality in univariate analysis were age over 60 yrs (p = 0.026), cardiovascular comorbidity (p = 0.027) and end-stage renal failure with dependence on haemodialysis (p = 0.026). Patients with immune and nonimmune DAH had similar outcomes. Early outcome depended on nonpulmonary organ failures. Conversely, late outcome was related to age, cardiac comorbidities and the need for haemodialysis.
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Hemorragia/mortalidad , Pacientes Internos/estadística & datos numéricos , Enfermedades Pulmonares/mortalidad , Alveolos Pulmonares/irrigación sanguínea , Adulto , Anciano , Comorbilidad , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Hipertensión Pulmonar/mortalidad , Estimación de Kaplan-Meier , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Modelos Logísticos , Enfermedades Pulmonares Intersticiales/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Diálisis Renal/mortalidad , Síndrome de Dificultad Respiratoria/mortalidad , Estudios RetrospectivosRESUMEN
The anti-CD20 antibody rituximab has been reported to induce a heterogeneous spectrum of lung disorders. The aim of the present study was to critically review data on the clinical presentations, causality assessments and management strategies of lung diseases possibly related to rituximab. A systematic literature review was performed on English-language reports in PubMed until September 2008. Cases of lung diseases ascribed to rituximab (n = 45) were identified, with three time-to-onset patterns. The most common presentation was acute/subacute hypoxaemic organising pneumonia (n = 37), starting 2 weeks after the last infusion (often around the fourth cycle) and resolving, in most cases, provided glucocorticoid therapy was given early. Acute respiratory distress syndrome occurred in five patients, within a few hours and usually after the first infusion. In the remaining three patients, macronodular organising pneumonia developed insidiously long after rituximab therapy and responded to steroids. Eight patients died. Based on time to onset, symptoms, and responses to discontinuation and rechallenge with rituximab and other drugs, 13 cases were highly compatible and 32 compatible with rituximab-induced lung disease. Knowledge of these presentations of rituximab-induced lung disease should prove helpful for diagnosis and causality assessment purposes. Time-to-onset data, suggesting different pathogenic mechanisms, support closer clinical and perhaps radiological monitoring between infusions, particularly in patients with a history of reversible respiratory symptoms.
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Anticuerpos Monoclonales/efectos adversos , Factores Biológicos/efectos adversos , Enfermedades Pulmonares Intersticiales/inducido químicamente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino , Hipersensibilidad a las Drogas/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Dificultad Respiratoria/inducido químicamente , RituximabRESUMEN
OBJECTIVE OF THE STUDY: To know the mechanisms and causes of death in Vietnamese VIH-infected patients hospitalized for tuberculosis. METHODS: Retrospective analysis of a monocentric cohort of 143 consecutive co infected patients admitted to Pham Ngoc Thach Hospital, in Ho Chi Minh City, between January 2004 and November 2004. MAIN RESULTS: All the patients were HIV-infected and AFB smear positive. The CD4 T lymphocyte count was 55/mm3 and the body mass index was 15.8 +/- 2 kg/m2. During the first three months after hospital admission and tuberculosis diagnosis, the percentage of deaths was 28.7% (41/143). The mechanisms of deaths were: progressive cachexia, acute respiratory failure, cardiogenic or bacteremic shock, coma and unexpected cardio respiratory arrest. The causes of death were tuberculosis (particularly mechanical complications such as compressive pneumothorax, pericarditis or pleuritis), metabolic disorders (mainly hyponatrémie and dyskaliema) and associated infection. In multivariate analysis, two parameters (available at admission) were predictive of short-term death: anemia (p=0.024) and hyponatrémie (p=0.026). CONCLUSION: The short term mortality of co infected patients with AIDS and tuberculosis remains high in developing countries. However, some causes of death such as compressive pneumothorax-pleuritis-pericarditis, metabolic disorder or even associated opportunistic infection i. e. pneumocystosis may be prevented or cured. Consequently, such patients must be carefully monitored and more particularly those with severe anemia and/or hyponatrémie at admission. Similarly appropriate diagnostic algorithms must be used in case of unfavorable evolution particularly to diagnose curable complication.
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Infecciones Oportunistas Relacionadas con el SIDA/mortalidad , Infecciones por VIH/mortalidad , Tuberculosis Pulmonar/mortalidad , Adulto , Índice de Masa Corporal , Recuento de Linfocito CD4 , Caquexia/mortalidad , Estudios de Cohortes , Coma/mortalidad , Muerte Súbita Cardíaca/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Hiponatremia/mortalidad , Masculino , Persona de Mediana Edad , Pericarditis/mortalidad , Pleuresia/mortalidad , Neumotórax/mortalidad , Insuficiencia Respiratoria/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Choque Cardiogénico/mortalidad , Choque Séptico/mortalidad , Vietnam/epidemiologíaRESUMEN
The definition of broncho-pulmonary aspergillosis infections in non-immunocompromised patients remains vague and a wide range of clinical, radiological and pathological entities have been described with a variety of names, i.e. simple aspergilloma, complex aspergilloma, semi-invasive aspergillosis, chronic necrotizing pulmonary aspergillosis, chronic cavitary and fibrosing pulmonary and pleural aspergillosis, pseudomembranous tracheobronchitis caused by Aspergillus, and invasive aspergillosis. However, these disease entities share common characteristics suggesting that they belong to the same group of pulmonary aspergillosis infectious disorders: 1- a specific diathesis responsible for the deterioration in local or systemic defenses against infection (alcohol, tobacco abuse, or diabetes); 2- an underlying bronchopulmonary disease responsible or not for the presence of a residual pleural or bronchopulmonary cavity (active tuberculosis or tuberculosis sequelae, bronchial dilatation, sarcoidosis, COPD); 3- generally, the prolonged use of low-dose oral or inhaled corticosteroids and 4- little or no vascular invasion, a granulomatous reaction and a low tendency for metastasis. There are no established treatment guidelines for broncho-pulmonary aspergillosis infection in non-immunocompromised patients, except for invasive aspergillosis. Bronchial artery embolization may stop hemoptysis in certain cases. Surgery is generally impossible because of impaired respiratory function or the severity of the comorbidity and when it is possible morbidity and mortality are very high. Numerous clinical cases and short retrospective series have reported the effect over time of the various antifungal agents available. Oral triazoles, i.e. itraconazole, and in particular voriconazole, appear to provide suitable treatment for broncho-pulmonary aspergillosis infections in non-immunocompromised patients.
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Aspergilosis/inmunología , Inmunocompetencia/inmunología , Enfermedades Pulmonares Fúngicas/inmunología , Antifúngicos/uso terapéutico , Aspergilosis/clasificación , Aspergilosis/diagnóstico , Aspergilosis/terapia , Humanos , Enfermedades Pulmonares Fúngicas/clasificación , Enfermedades Pulmonares Fúngicas/diagnóstico , Enfermedades Pulmonares Fúngicas/terapia , NeumonectomíaRESUMEN
Establishing the diagnosis of drug-related pulmonary disease (DRPD) remains a difficult task because of the large number of drug-related toxic situations and the variety of clinical presentations. PneumoDoc is a computer-based support system designed to facilitate the diagnosis of lung disease using chronological, clinical, imaging, and cytological (alveolar lavage) input. These intrinsic items are crosschecked against extrinsic items reported in the literature (Pneumotox). Data input is in the form of yes-no questions. The final output displays the characteristic features of the observed clinical situation and calculates the probability of DRPD defined in five categories: incompatible, doubtful, compatible, suggestive, and highly suggestive. Use of multiple drugs, interaction with cardiopulmonary disease, and the absence of reported cases are limitations of the system.
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Diagnóstico por Computador , Enfermedades Pulmonares/inducido químicamente , Árboles de Decisión , Sistemas Especialistas , Humanos , Bases del Conocimiento , Redes Neurales de la ComputaciónRESUMEN
Bronchiectasis, cancer and tuberculosis account for the majority of haemoptysis requiring intensive care unit admission. Bedside evaluation (volume and bronchoscopic active bleeding) is safe to screen patients for arteriography and bronchial artery embolisation (BAE). First-line interventional arteriography should be favour over surgery in patients with non traumatic life-threatening hemoptysis. Surgery must be reserved in cases of failure or recurrence of bleeding after BAE.
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Cuidados Críticos , Hemoptisis/terapia , Sangre , Broncoscopía , Embolización Terapéutica , Hemoptisis/clasificación , Hemoptisis/etiología , Hemoptisis/cirugía , Hospitales Universitarios , Humanos , Terapia por Inhalación de Oxígeno , Paris , Tomografía Computarizada por Rayos XAsunto(s)
Departamentos de Hospitales/tendencias , Medicina Interna/tendencias , Cardiología/organización & administración , Cardiología/tendencias , Predicción , Departamentos de Hospitales/organización & administración , Humanos , Medicina Interna/organización & administración , Paris , Neumología/organización & administración , Neumología/tendencias , Resucitación , Cirugía Torácica/organización & administración , Cirugía Torácica/tendenciasRESUMEN
The risk of Pseudomonas aeruginosa (Pa) acquisition, colonization, and infection during chronic bronchial disease varies according to the disease (cystic fibrosis, bronchial dilatation, post-tobacco abuse chronic obstructive bronchopneumonia), its evolutive stage, and a number of known or suspected factors. The involvement of Pa marks an important evolution of the disease, well demonstrated in cystic fibrosis. P. aeruginosa can adhere to epithelial cells (initial colonization) then organizes itself in complex structures evolving from simples microcolonies to macrocolonies in a structured biofilm supporting chronic colonization. P. aeruginosa can produce several factors of virulence, leading to the permanent destruction of host cells, thus inducing the regular liberation of pro-inflammatory mediators implementing a vicious circle worsening these chronic respiratory diseases and favoring their exacerbation. Chronic Pa suppuration has a systemic impact and justifies a global multidisciplinary management. In cystic fibrosis, the presence of P. aeruginosa is a major prognostic element. The current consensus is to detect the primary colonization as early as possible eradication is still possible and to treat it before it evolves to chronicity. But right now, this type of management has not been justified for other chronic bronchial diseases.
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Enfermedades Bronquiales/microbiología , Infecciones por Pseudomonas/epidemiología , Francia/epidemiología , Humanos , Incidencia , Pseudomonas aeruginosa , Medición de RiesgoAsunto(s)
Tos/terapia , Guías de Práctica Clínica como Asunto , Enfermedad Crónica , Francia , Humanos , Neumología , Sociedades MédicasAsunto(s)
Tos/diagnóstico , Tos/epidemiología , Técnicas de Diagnóstico del Sistema Respiratorio , Factores de Edad , Enfermedad Crónica , Europa (Continente)/epidemiología , Humanos , Prevalencia , Calidad de Vida , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios , Terminología como Asunto , Estados Unidos/epidemiologíaAsunto(s)
Tos/etiología , Enfermedades Respiratorias/complicaciones , Asma/complicaciones , Neoplasias de los Bronquios/complicaciones , Enfermedad Crónica , Tos/epidemiología , Tos/fisiopatología , Contaminación Ambiental/efectos adversos , Francia/epidemiología , Humanos , Neoplasias Pulmonares/complicaciones , Fumar Marihuana/efectos adversos , Fumar Marihuana/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Eosinofilia Pulmonar/complicaciones , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/fisiopatología , Fumar/efectos adversos , Fumar/epidemiología , Tuberculosis Pulmonar/complicaciones , Tos Ferina/complicacionesAsunto(s)
Tos/etiología , Asma/complicaciones , Enfermedades Autoinmunes/complicaciones , Enfermedad Crónica , Tos/fisiopatología , Medicamentos Esenciales/efectos adversos , Enfermedades del Sistema Endocrino/complicaciones , Insuficiencia Cardíaca/complicaciones , Humanos , Trastornos Mentales/complicaciones , Enfermedades del Sistema Nervioso/complicaciones , Rinitis Alérgica Perenne/complicacionesRESUMEN
Diagnostic probability of community-acquired pneumonia (CAP) depends on data related to age and clinical and radiological findings. The critical evaluation of data in the literature leads to the following conclusions: 1) the prevalence of CAP in a given population with acute respiratory disease is 5% in outpatients and 10% in an emergency care unit. This could be as low as 2% in young people and even higher than 40% in hospitalized elderly patients; 2) the collection of clinical data is linked to the way the patient is examined and to the expertise of the clinician. The absolute lack of "vital signs" has a good negative predictive value in CAP; presence of unilateral crackles has a good positive predictive value; 3) there is a wide range of X-ray abnormalities: localized alveolar opacities; interstitial opacities, limited of diffused. The greatest radiological difficulties are encountered in old people with disorders including chronic respiratory or cardiac opacities and as a consequence of the high prevalence of bronchopneumonia episodes at this age; 4) among patients with lower respiratory tract (LRT) infections, the blood levels of leukocytes, CRP and procalcitonine are higher in CAP patients, mainly when their disease has a bacterial origin. Since you have not a threshold value reliably demonstrated in large populations with LRT infections or acute respiratory disease, presence or absence of these parameters could only be taken as a slight hint for a CAP diagnosis.