Neumonía asociada a la ventilación mecánica (NAVM): factores de riesgo relacionados con la presencia de gérmenes multirresistentes(AU) / Ventilator-associated pneumonia: risk factors associated with the presence of multiresistant organism

La Neumonía Asociada a la Ventilación Mecánica (NAVM) afecta entre 10 por ciento y 65 por ciento de los pacientes, con una mortalidad atribuible que fluctúa entre 24 por ciento y 76 por ciento. Numerosas directrices recomiendan dividir la NAVM en precoz si ocurre dentro de las primeras 96 horas de ingreso a UCI o tardía si es posterior, ya que las tardías suelen ser ocasionadas por patógenos multirresistentes (PMR). Objetivo: Determinar si hay asociación entre la presencia de PMR con la NAVM tardía, uso previo de antibióticos, comorbilidady gravedad al ingreso a la UCI. Métodos: Estudio prospectivo de 12 meses. El diagnóstico de NAVM fue clínico asociado a cultivo cuantitativo en contaje significativo (106 UFC/ml para cultivo cuantitativo de aspirado endotraqueal, 104 UFC/ml para lavado broncoalveolar (LBA) vía broncoscópica). Resultados: Se enrolaron 48 pacientes con NAVM consecutivos, 19 mujeres, la edad promedio fue de 59+/-18,5 años. Los principales gérmenes involucrados fueron St Aureus meticilino resistente (54 por ciento), Acinetobacter sp (33 por ciento) y Pseudomonas aeruginosa (19 por ciento). El aislamiento de PMR no se asoció significativamente a la NAVM tardía (p >0,05), por el contrario el uso previo de antibióticos se relacionó más estrechamente con la presencia de PMR (p <0,0001). Al analizar variables clínicas sólo la escala de Glasgow más baja al ingreso a la UCI se asoció significativamente con la presencia de PMR (10,7+/-3,3 vs14,5+/-0,5, p <0,05). Conclusión: El uso previo de antibióticos se asocia significativamente a la neumonía por PMR independiente del momento en que se diagnostica la NAVM.

Ventilator-associated pneumonia (VAP) is a mechanical ventilation complication that affects about 10 percent to 65 percent of mechanical ventilated patients. The attributable mortality ranged between 24 percent to 76 percent. Most of the guidelines have recommended to classify VAP in early onset if diagnosis is made in the first 96 hours from ICU admission or late onset if the diagnosis is later. Early onset VAP is reported to be due to antibiotic-sensitive pathogens, while late-onset VAP is frequently attributed to antibiotic-resistant pathogens (ARP). The Aim of the study was to correlate the isolate of ARP with late-onset VAP, prior antimicrobial treatment, comorbidity and severity of illnesses. Methods: 12 months prospective study. VAP was define according a presumptive clinical diagnosis plus an isolation of a pathogen in a significant concentration (>106 CFU/ml for quantitative cultures of endotracheal aspirates, >104 CFU/ml for bronchoalveolar lavage from fiberoptic bronchoscopic). Results:We included 48 patients with VAP, 19 women, the average age was 59 +/- 18,5 years. 75 percent (36/48) were late-onset VAP. The organism most frequently isolated was methicillin resistant S. aureus (54 percent), Acinetobacter sp (33 percent), and Pseudomona aeruginosa (19 percent). ARP was not associated with late-onset VAP (p >0,05), by contrast prior antimicrobial treatment was closely associated to isolation of ARP (p<0,001). When analyzed clinical variables only lower Glasgow coma scale at ICU admission was associated with ARP-VAP (10,7+/-3,3 vs 14,5+/-0,5 p <0,05). Conclusion: Prior antimicrobial treatment was closely associated with ARP-VAP regardless of the timing of VAP Diagnosis.

Risk factors for Hospital-Acquired Pneumonia in nonventilated adults

Although most recent publications focus on Ventilator-associated Pneumonia, Non-Ventilator-associated Hospital-acquired pneumonia (NVHAP) is still worrisome. We studied risk factors for NVHAP among patients admitted to a small teaching hospital. Sixty-six NVHAP case patients and 66 controls admitted to the hospital from November 2005 through November 2006 were enrolled in a case-control study. Variables under investigation included: demographic characteristics, comorbidities, procedures, invasive devices and use of medications (Sedatives, Antacids, Steroids and Antimicrobials). Univariate and multivariable analysis (hierarchical models of logistic regression) were performed. The incidence of NVHAP in our hospital was 0.68 percent (1.02 per 1,000 patients-day). Results from multivariable analysis identified risk factors for NVHAP: age (Odds Ratio[OR]=1.03, 95 percent Confidence Interval[CI]=1.01-1.05, p=0.002), use of Antacids (OR=5.29, 95 percentCI=1.89-4.79, p=0.001) and Central Nervous System disease (OR=3.13, 95 percentCI=1.24-7.93, p=0.02). Although our findings are coherent with previous reports, the association of Antacids with NVHAP recalls a controversial issue in the physiopathology of Hospital-Acquired Pneumonia, with possible implications for preventive strategies.

Neumonía adquirida en la comunidad (NAC) y asociada al cuidado crónico de la salud (NACS) en 560 mayores de 65 años / Community-acquired pneumonia and associated chronic health care in 560 older than 65 year

Los mayores de 65 tienden a desarrollar neumonía. Evaluamos la epidemiología, el impacto de los factores de riesgo y las comorbilidades y el pronóstico de NAC y NACS en una cohorte de ancianos. Métodos. Se recolectaron prospectivamente datos en mayores de 65 años no-inmunosuprimidos, atendidos por NAC y NACS. Se definió neumonía por criterios clínicos y radiológicos; considerándose NAC en no internados durante los 15 días previos y NACS si además residían en alguna institución de cuidado crónico o geriátrico. Resultados. De 844 pacientes con NAC, 560 eran mayores de 65 (66.4%), y 100 (el 17.9% de ellos) eran NACS. Mediante análisis univariado se determinó que los portadores de NACS eran mayores, debieron internarse o se habían internado anteriormente por neumonía u otra razón más frecuentemente; también los pacientes con NACS presentaban más frecuentemente comorbilidad neurológica, conciencia alterada, aspiración, uso previo de antibióticos y clase V del PSI (p < 0.001 para todos estos). En análisis multivariado solo la edad mayor de 80 y la comorbilidad neurológica permanecieron más frecuentes en NACS. Los agentes más comunes fueron S. pneumoniae, M. pneumoniae, C. pneumoniae, L. pneumophila, P. aeruginosa, enterobacterias, S. aureus, H. influenzaey virus. No hubo diferencias en etiología entre NAC y NACS. La mortalidad a 30 días fue mayor en los pacientes con NACS (44.5 vs. 33.7%). Conclusión. En mayores de 65 la neumonía es más frecuente, más grave y su etiología es diferente respecto de los menores. La NACS presenta más gravedad y mayor mortalidad.

People older than 65 years are more susceptible to pneumonia. This paper presents an assessment of the impact of risk factors and co-morbidities and the prognosis of community-acquired pneumonia (CAP) and health care associated community-acquised pneumonia (HCAP) in the elderly. Methods. Prospective data collection in immuno-competent patients older than 65 years hospitalized for CAP or HCAP. Pneumonia was defined by radiographic and clinical criteria; CAP was considered in patients who were not hospitalized during the previous 15 days, while HCAP was diagnosed in those who developed pneumonia outside the hospital in a nursing home or long-term health care facility. Results. Out of 844 patients admitted with the diagnosis of pneumonia during 5 years, 560 were older than 65 (66.4%); 460 (54.6%) were classified as CAP and 100 (17.9%) as HCAP. In comparison with the CAP patients, patients with HCAP were older and had more often been admitted in the past for pneumonia or other reason, (p < 0.001). They also presented a higher frequency of neurologic co-morbidity, altered consciousness, aspiration, use of prior antibiotics and high risk pneumonia (risk class V of the Pneumonia Severity Index - PSI) (p < 0.001). In the multivariate analysis, age older than 80 and neurologic co-morbidity were more often significantly associated with HCAP. The more frequent identified microbial agents were S. pneumoniae, M. pneumoniae, C. pneumoniae, L.pneumophila, P. aeruginosa, enteric Gram - negative bacteria, S. aureus, H. influenzae and viruses. The etiology of CAP and HCAP was similar. Thirty - day mortality was higher in HCAP (44.5 vs. 33.7%). Conclusion. In patients older than 65, CAP is more frequent and severe, and the microbial etiology is different than in CAP of younger people. HCAP is even more severe and has higher mortality.

Ventilator-associated pneumonia in an adult clinical-surgical intensive care unit of a Brazilian university hospital: incidence, risk factors, etiology, and antibiotic resistance

The objective of this study was to evaluate clinical characteristics, etiology, and resistance to antimicrobial agents, among patients with ventilator-associated pneumonia (VAP). A case study vs. patients control under mechanical ventilation and hospitalized into clinical-surgical adults ICU of HC-UFU was performed from March/2005 to March/2006. Patients under ventilation for over 48 h were included in the study including 84 with diagnosis of VAP, and 191 without VAP (control group). Laboratory diagnosis was carried out through quantitative microbiological evaluation of tracheal aspirate. The identification of pathogens was performed by classical microbiological tests, and the antibiotics sensitivity spectrum was determined through the CLSI technique. VAP incidence rate over 1,000 days of ventilation was 24.59. The mean (± SD) duration of mechanical ventilation prior to VAP diagnosis was 23.2 ± 17.2 days. By multivariate analysis the risk factors predisposing for VAP were: mechanical ventilation time and mechanical ventilation > seven days, tracheostomy and use of > three antibiotics. Mortality rate was high (32.1 percent) but lower than that of the control group (46.5 percent). Major pathogens were identified in most of patients (95.2 percent) and included: Pseudomonas aeruginosa (29 percent), Staphylococcus aureus (26 percent), Enterobacter/Klebsiella/Serratia (19 percent) and Acinetobacter spp. (18 percent), with expressive frequencies of P. aeruginosa (52 percent), S. aureus (65.4 percent) and Enterobacteriaceae (43.7 percent) resistant to imipenem, oxacillin and 3/4 generation cephalosporins, respectively. In conclusion, our observation showed VAPs caused by multiresistant microorganisms, the prescription of > three antibiotics, and mortality with unacceptably high rates. The practice of de-escalation therapy appears to be urgently needed in order to improve the situation.

Neumonía por virus parainfluenza 3 en paciente inmunocomprometido / Parainfluenza 3 pneumonia in an immunocompromised patient

Un paciente de 45 años bajo tratamiento corticoidal por una probable sarcoidosis y una pancitopenia moderada ingresa por una neumonía que no responde a antibióticos ni a tratamiento antimicótico indicado a raíz del aislamiento de Aspergillus fumigatus en expectoración. Desarrolla una insuficiencia respiratoria progresiva e hipotensión y una inmunofluorescencia para virus parainfluenza 3 resulta positiva. Fallece al séptimo día y la necropsia muestra una neumonía necrotizante, daño alveolar difuso y abundantes partículas virales.

Pneumonias comunitárias / Community acquired pneumonias

São apresentadas as pneumonias mais comuns adquiridas na comunidade, com discussão dos aspectos diagnósticos, condutas terapêuticas e preventivas

Neumonía extrahospitalaria del adulto mayor / Extrahospitalary pneumonia of the senior adults

La neumonía del adulto mayor es una afección frecuente y seria, que tiene características especiales en sus manifestaciones clínicas; en su expresión semiológica y radiológica y en su comportamiento en lo que respecta a evolución, resolución y respuesta al tratamiento antibiótico. Lo anterior se debe a las modificaciones provocadas por la edad y las afecciones crónicas en los mecanismos defensivos celulares y humorales frente a las infecciones respiratorias bacterianas y virales. Dado que su pronóstico depende en gran medida de la oportunidad del tratamiento antibiótico, se enfatiza la necesidad de sospechar y pesquisar la posibilidad de neumopatía aguda, en el sujeto de edad aún frente a manifestaciones clínicas atípicas y larvadas. Se hace hincapié, asimismo, en la utilidad pero también en las limitaciones de los exámenes bacteriológicos y de la radiografía de tórax. Se señala la utilidad de los tratamientos antibióticos asociados. Finalmente se mencionan las principales complicaciones, destacando, entre ellas, la resolución lenta o aún la no resolución de algunas neumonías del anciano, enumerando sus principales causas