Characteristics and local risk factors of community-acquired and health-care-associated Staphylococcus aureus pneumonia.

This study aims at identifying characteristics, risk factors and mortality of community-acquired (CAP) and health-care-associated pneumonia (HCAP) by Staphylococcus aureus (S. aureus). We retrieved adults with S. aureus CAP or HCAP diagnosed by blood or pleural effusion culture in 2.6 years, and compared with those of Streptococcus pneumoniae (S. pneumoniae) CAP or HCAP diagnosed by blood or respiratory culture, or urine antigen. We found 18 patients with CAP and 9 HCAP due to S. aureus (female 33%, 66.6 ± 12.4 years-old), and 48 patients with CAP and 15 HCAP due to S pneumoniae (female 41%, 69.5 ± 17.5 years). Diabetes mellitus (52% vs. 24%, p = 0.019), hemodialysis (11% vs. 0%, p = 0.046), skin lesions (44% vs. 0%, p < 0.001), cavitary nodules (37% vs. 1.6%, p < 0.001) and pleural effusions (48% vs. 18%, p = 0.007) were more common in staphylococcal than pneumococcal group. Three patients with staphylococcal pneumonia had acute myocardial infarction. Pneumonia severity index (139 ± 52 vs. 109 ± 43, p = 0.005) and 30-day mortality (41% vs. 9.5%, p = 0.001) were higher in staphylococcal group. Multivariate analysis showed underlying disease (especially cancer and cirrhosis), risk class 4/5, altered mentality, shock and bilateral pneumonia were risk factors for 30-day mortality.

Predictive Value of the Methicillin-Resistant Staphylococcus aureus Nasal Swab for Methicillin-Resistant Staphylococcus aureus Ventilator-Associated Pneumonia in the Trauma Patient.

Background: Many trauma centers have empiric treatment algorithms for ventilator-associated pneumonia (VAP) treatment prior to culture results that include antibiotic agents for methicillin-resistant Staphylococcus aureus (MRSA) coverage that can have adverse effects. This is the only study to evaluate risk factors and MRSA nasal swabs to risk-stratify trauma patients for MRSA VAP, thereby potentially limiting the need for empiric vancomycin. Patients and Methods: This was a single institution retrospective cohort study. Adult patients admitted to the trauma intensive care unit (ICU) between January 2013 and December 2017 who had a MRSA nasal swab and subsequently met criteria for VAP were included. Demographics, risk factors for MRSA pneumonia, and culture results were collected. Results: A total of 140 patients met inclusion criteria. The negative predictive value (NPV) of MRSA nasal swab at predicting subsequent MRSA pneumonia was 97%. The sensitivity, specificity, and positive predictive value were 50.0%, 96.2%, and 44.4%, respectively. Smokers were more likely to develop MRSA pneumonia, odds ratio: 7.0 (p = 0.02). When considering non-smokers with a negative MRSA nasal swab, NPV was 100%. Conclusions: This is the only study to date that assesses the utility of MRSA nasal swab and risk factor data to guide empiric VAP antibiotic therapy in trauma patients. Smoking was found to be a risk factor for MRSA pneumonia. The use of MRSA nasal swabs in combination with smoking status to guide empiric use of MRSA coverage antibiotic agents is recommended because of a 100% NPV. When utilized, as many as 68% of patients may safely be spared MRSA coverage antibiotic agents and the related adverse effects.

Healthcare-associated pneumonia: a prospective study in Spain.

OBJECTIVE: The aim of the study was to describe the epidemiological characteristics and factors related to outcome in Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated pneumonia (HCAP). METHODS: A 3-year prospective observational epidemiological case study of HCAP was conducted in seven Spanish hospitals. Microbiological and patient characteristics and outcomes were collected and classified by causative pathogen into 4 categories: "S. pneumoniae", "MRSA", "Others" and "Unknown". Patients were followed up 30 days after discharge. RESULTS: A total of 258 (84.6%) patients were enrolled (170 were men [65.9%]). Mean age was 72.4 years ± 15 years (95% CI [70.54-74.25]). The etiology of pneumonia was identified in 73 cases (28.3%): S. pneumoniae in 35 patients (13.6%), MRSA in 8 (3.1%), and other microorganisms in 30 patients (11.6%). Significant differences in rates of chronic obstructive pulmonary disease (p < 0.05), previous antibiotic treatment (p<0.05), other chronic respiratory diseases, inhaled corticosteroids (p <0.01), and lymphoma (p < 0.05) were observed among the four groups. Patients with MRSA pneumonia had received more previous antibiotic treatment (87.5%). Thirty-three (12.8%) patients died during hospitalisation; death in 27 (81.2%) was related to pneumonia. CONCLUSIONS: The etiology of HCAP was identified in only one quarter of patients, with S. pneumoniae being the most prevalent microorganism. Patients with chronic respiratory diseases more frequently presented HCAP due to MRSA than to S. pneumoniae. Death at hospital discharge was related in most cases to pneumonia.

Childhood pneumonia in low-and-middle-income countries: An update.

OBJECTIVES: To review epidemiology, aetiology and management of childhood pneumonia in low-and-middle-income countries. DESIGN: Review of published English literature between 2013 and 2019. RESULTS: Pneumonia remains a major cause of morbidity and mortality. Risk factors include young age, malnutrition, immunosuppression, tobacco smoke or air pollution exposure. Better methods for specimen collection and molecular diagnostics have improved microbiological diagnosis, indicating that pneumonia results from several organisms interacting. Induced sputum increases microbiologic yield for Bordetella pertussis or Mycobacterium tuberculosis, which has been associated with pneumonia in high TB prevalence areas. The proportion of cases due to Streptococcus pneumoniae and Haemophilus influenzae b has declined with new conjugate vaccines; Staphylococcus aureus and H. influenzae non-type b are the commonest bacterial pathogens; viruses are the most common pathogens. Effective interventions comprise antibiotics, oxygen and non-invasive ventilation. New vaccines have reduced severity and incidence of disease, but disparities exist in uptake. CONCLUSION: Morbidity and mortality from childhood pneumonia has decreased but a considerable preventable burden remains. Widespread implementation of available, effective interventions and development of novel strategies are needed.

Prior oropharyngeal colonization and ventilator-associated pneumonia

This study evaluated the relationship between previous colonization of the oropharynx and development of ventilator-associated pneumonia through the classification of genomic fingerprint pattern by pulsed-field gel electrophoresis of both oxacillin-resistant and oxacillin-susceptible Staphylococcus aureus isolates obtained from hospitalized patients in an intensive care unit.

Predictors of the pathogenicity of methicillin-resistant Staphylococcus aureus nosocomial pneumonia.

BACKGROUND AND OBJECTIVE: The clinical characteristics of patients with nosocomial pneumonia (NP) associated with methicillin-resistant Staphylococcus aureus (MRSA) infection are not well characterized. METHODS: Three hundred and thirty-seven consecutive patients with MRSA isolation from respiratory specimens who attended our hospital between April 2007 and March 2011 were enrolled. Patients characteristics diagnosed with 'true' MRSA-NP were described with regards to clinical, microbiological features, radiological features and genetic characteristics of the isolates. The diagnosis of 'true' MRSA-NP was confirmed by anti-MRSA treatment effects, Gram-staining or bronchoalveolar lavage fluid culture. RESULTS: Thirty-six patients were diagnosed with 'true' MRSA-NP, whereas 34 were diagnosed with NP with MRSA colonization. Patients with a MRSA-NP had a Pneumonia Patient Outcomes Research Team score of 5 (58.3% vs 23.5%), single cultivation of MRSA (83.3% vs 38.2%), MRSA quantitative cultivation yielding more than 10(6) CFU/mL (80.6% vs 47.1%), radiological findings other than lobar pneumonia (66.7% vs 26.5%), and a history of head, neck, oesophageal or stomach surgery (30.6% vs 11.8%). These factors were shown to be independent predictors of the pathogenicity of 'true' MRSA-NP by multivariate analysis (P < 0.05). CONCLUSIONS: 'True' MRSA-NP shows distinct clinical and radiological features from NP with MRSA colonization.

Risk factors for methicillin-resistant Staphylococcus aureus in patients with community-onset and hospital-onset pneumonia.

OBJECTIVES: The risk factors for methicillin-resistant Staphylococcus aureus (MRSA) pneumonia have not been fully characterized and are likely to be different depending on whether infection is acquired in the community or the hospital. METHODS: We conducted a case-control study of 619 adults hospitalized between 2005 and 2010 with either MRSA or methicillin-sensitive S. aureus (MSSA) pneumonia. Patients with a respiratory culture within 48 h of hospitalization had community-onset pneumonia whereas patients with a culture collected after this time point had hospital-onset pneumonia. RESULTS: Among patients with community-onset disease, the risk for MRSA was increased by tobacco use (OR 2.31, CI 1.23-4.31), chronic obstructive pulmonary disease (OR 3.76, CI 1.74-8.08), and recent antibiotic exposure (OR 4.87, CI 2.35-10.1) in multivariate analysis while patients with hospital-onset disease had an increased MRSA risk with tobacco use (OR 2.66, CI 1.38-5.14), illicit drug use (OR 3.52, CI 2.21-5.59), and recent antibiotic exposure (OR 2.04, CI 3.54-13.01). Hospitalization within the prior three months was associated with decreased risk (OR 0.64, CI 0.46-0.89) in multivariate analysis. CONCLUSIONS: This study suggests there are common and distinct risk factors for MRSA pneumonia based on location of onset. The decreased risk for MRSA pneumonia associated with recent hospitalization is unexpected and warrants further investigation. SUMMARY: This case-control study showed that there are common and distinct risk factors associated with MRSA pneumonia depending on whether the infection onset is in the hospital or in the community. Recent hospitalization was unexpectedly shown to be associated with decreased risk for MRSA pneumonia and warrants further investigation.

Ventilator-associated pneumonia due to meticillin-resistant Staphylococcus aureus: risk factors and outcome in a large general hospital.

BACKGROUND: Data about risk factors and impact on outcome of methicillin-resistant S. aureus (MRSA) in unselected patients with ventilator-associated pneumonia (VAP) are limited. AIM: To assess predisposing factors and outcome of VAP due to MRSA in a large teaching institution. METHODS: Prospective study carried out over four years in the three adult ICUs of our hospital. Patients with MRSA-VAP were compared with those with bacterial VAP due to other microorganisms. FINDINGS: Overall, 474 episodes of bacterial VAP were collected. Significant differences between MRSA-VAP (111) and VAP due to other microorganisms (363) were found for median age (68 vs. 62 years), median APACHE II score (12 vs. 11), neurosurgery (5.4% vs. 13.8%), abdominal surgery (35% vs. 19%), prior treatment with any antibiotic (82.9% vs. 64.5%) and with imipenem (24% vs. 11%) at present admission before VAP, and pleural effusion (12% vs. 5%). Multivariate analysis adjusted for confounding factors showed that higher APACHE II score, prior treatment with any antibiotic and pleural effusion were independent risk factors for MRSA. As for treatment and outcome, the differences between MRSA-VAP and other VAP were inadequate empiric treatment (70% vs. 53%), median cost of antibiotics per episode (€974 vs. €726), and in-hospital mortality (60% vs. 47%). At multivariate analysis, however, MRSA was not found to be an independent risk factor for mortality. CONCLUSION: MRSA is a common cause of VAP. Underlying conditions predispose to its high mortality.

[MRSA bloodstream infections in hospitals in Frankfurt/Main, Germany, 2010 : Results of the mandatory notification and suggestions for improvement]. / MRSA in Blutkulturen in Frankfurter Krankenhäusern 2010 : Ergebnisse der Meldepflicht nach Infektionsschutzgesetz und Vorschläge zu ihrer Verbesserung.

Since 1 July 2009 in accordance with the statuary order based on the German law for infectious diseases (Infektionsschutzgesetz), MRSA in blood and liquor must be notified to the public health authorities. The aim of extension of the notification to report is to improve the surveillance of nosocomial infections and the prevention of nosocomial MRSA infections. In addition to MRSA detection, data on symptoms and risk factors, e.g., medical devices, must also be reported. In this report, data of bloodstream MRSA infections in hospitals in Frankfurt/Main, Germany, for the first complete year (2010)were evaluated. In 2010, 58 MRSA-positive bloodstream infections were reported by the 17 hospitals in Frankfurt to the health protection authorities, i.e., 0.0360 MRSA/1,000 patient-days (range: 0- 0.109/1,000 patient-days). However, 10 of these infections initially had not been reported to the public health department in charge for the hospitals, but to the health departments according to the patient's addresses. Although most of the infections were reported from large hospitals (>100,000 patient-days/year), the highest incidences (0.0416/1,000 patient-days) were reported from small hospitals (<50,000 patient-days/year). Of the blood specimen, 13 (22.4%) were drawn on the first day of hospital stay, thus, indicating an imported infection. While 90% of the patients with MRSA in the bloodstream suffered from fever, 80% had sepsis and 34.5% suffered from pneumonia. Medical devices, such as central venous catheters and PEG, were reported from 60% of the patients. In the MRE network Rhine-Main region, the public health authorities asked for some more detailed information, such as risk factors for MRSA colonization (history for MRSA, recent hospital stay or antibiotic therapy, skin disorders, dialysis, residence in a retirements home), and for screening results as well as for the MRSA management, i.e., isolation of the patient and, if necessary, the contact patient. In 55% of the cases, the patients were identified by the clinics themselves as being patients with MRSA risk factors, mainly because of a history of MRSA (29%), recent hospital stay (71%), and antibiotic therapy during the last 6 months (52%). Screening was performed in 31 (53%) of the patients, most of them (71%) with positive MRSA nose swab. If the patients were screened, significantly fewer contact patients had to be screened and isolated later. Thus, to improve surveillance data on MRSA bloodstream infections, the notification route to the public health authorities responsible for the clinic hosting the patient must be strictly obeyed in order to avoid underreporting und underassessment of nosocomial infection. Although asking for clinical symptoms may be useful to validate the result in some cases, focus should be placed on risk factors and risk management, including screening and isolation. Only then can the aim of improving surveillance and reduction of nosocomial MRSA infection be achieved.

Nosocomial MRSA pneumonia: data from recent clinical trials.

MRSA infections, especially pneumonia have been associated with considerable morbidity and mortality and the management of MRSA infections is considered as an issue of high priority for scientific societies. Many studies which have been published during the last 10 years have provided evidence for MRSA pneumonia epidemiology, diagnosis and treatment. The main regime of antibiotic treatment recommended for MRSA pneumonia is either vancomycin or linezolid. Despite its pK/pD superiority over vancomycin, linezolid has to date failed to show clear advantage over vancomycin in recent clinical trials.

Impact of Staphylococcus aureus on the pathogenesis of chronic cystic fibrosis lung disease.

One of the first pathogens which can be isolated from the airways of cystic fibrosis (CF) patients is Staphylococcus aureus, which often persists in this hostile environment for many months or even years. The increase in infections due to the methicillin-resistant S. aureus (MRSA) worldwide and even more the emergence of community-acquired MRSA, which differ from nosocomial MRSA by lack of multiresistance and carriage of a phage-encoded toxin, Panton-Valentine leukocidin, attracts new attention to the epidemiology, pathogenesis, and impact of S. aureus in the background of CF. In this review, recent data and studies will be reported and discussed to give an overview of the latest research.

Necrotizing pneumonia in children submitted to thoracoscopy due to pleural empyema: incidence, treatment and clinical evolution.

OBJECTIVE: To assess the incidence of necrotizing pneumonia (NP) in children submitted to thoracoscopy, comparing patients with and without NP in terms of the presentation and clinical evolution. METHODS: A retrospective study of children with pleural empyema submitted to thoracoscopy. Thoracoscopy was performed in patients not previously submitted to thoracic drainage and in whom there was evidence of loculated effusion or pneumothorax, as well as in those previously submitted to thoracic drainage and in whom there was persistent pneumothorax or fever with purulent discharge. On the basis of the thoracoscopy findings, patients were distributed into two groups: those with NP (NP group) and those without (no-NP group). RESULTS: The study sample comprised 52 patients. Of the 24 patients with NP, 19 (79%) had undergone thoracic drainage prior to thoracoscopy, 11 (46%) presented with pneumothorax, and 16 (67%) developed bronchopleural fistula. In the NP group, the median drainage time and the median length of hospital stay were 18 and 19 days, respectively. Of the 28 patients without NP, 10 (36%) had undergone thoracic drainage prior to thoracoscopy, 9 (32%) presented pneumothorax, and 5 (18%) developed bronchopleural fistula. In the no-NP group, the median drainage time and the median length of hospital stay were 6 and 10 days, respectively. CONCLUSIONS: Pneumothorax should raise the suspicion of NP. Early thoracoscopy can be a valuable treatment option for NP in children because it hastens recovery in comparison with the medical treatment alone and avoids extensive late thoracotomy lung resections.

Pneumonia necrosante em crianças submetidas à toracoscopia por empiema pleural: incidência, tratamento e evolução clínica / Necrotizing pneumonia in children submitted to thoracoscopy due to pleural empyema: incidence, treatment and clinical evolution

OBJETIVO: Analisar a incidência de pneumonia necrosante (PN) em crianças submetidas a toracoscopia e comparar pacientes com e sem PN em relação às diferentes apresentações e evolução clínica. MÉTODOS: Estudo retrospectivo de crianças portadoras de empiema e submetidas a toracoscopia. A toracoscopia foi realizada em pacientes não submetidos a drenagem torácica prévia e evidência de derrame septado ou pneumotórax, assim como naqueles submetidos previamente a drenagem torácica e pneumotórax persistente ou febre e secreção purulenta. Baseado na presença de PN durante a toracoscopia, os pacientes foram divididos em dois grupos: com PN e sem PN. RESULTADOS: Participaram do estudo 52 pacientes. Dos 24 pacientes com PN, 19 (79 por cento) foram submetidos a drenagem torácica anterior à toracoscopia, 11 (46 por cento) apresentaram pneumotórax, e 16 (67 por cento) evoluíram com fístula broncopleural. Neste grupo, as medianas do tempo de drenagem e de hospitalização foram, respectivamente, 18 e 19 dias. Dos 28 pacientes sem PN, 10 (36 por cento) foram submetidos a drenagem torácica anterior à toracoscopia, 9 (32 por cento) apresentaram pneumotórax, e 5 (18 por cento) evoluíram com fístula broncopleural. Neste grupo, as medianas do tempo médio de drenagem e de hospitalização foram, respectivamente, 6 e 10 dias. CONCLUSÕES: A PN deve ser suspeitada na presença de pneumotórax. A toracoscopia precoce pode ser uma opção terapêutica de grande valor na PN da infância, pois acelera a recuperação quando comparada ao tratamento médico isolado e evita ressecções pulmonares extensas da toracotomia tardia.

OBJECTIVE: To assess the incidence of necrotizing pneumonia (NP) in children submitted to thoracoscopy, comparing patients with and without NP in terms of the presentation and clinical evolution. METHODS: A retrospective study of children with pleural empyema submitted to thoracoscopy. Thoracoscopy was performed in patients not previously submitted to thoracic drainage and in whom there was evidence of loculated effusion or pneumothorax, as well as in those previously submitted to thoracic drainage and in whom there was persistent pneumothorax or fever with purulent discharge. On the basis of the thoracoscopy findings, patients were distributed into two groups: those with NP (NP group) and those without (no-NP group). RESULTS: The study sample comprised 52 patients. Of the 24 patients with NP, 19 (79 percent) had undergone thoracic drainage prior to thoracoscopy, 11 (46 percent) presented with pneumothorax, and 16 (67 percent) developed bronchopleural fistula. In the NP group, the median drainage time and the median length of hospital stay were 18 and 19 days, respectively. Of the 28 patients without NP, 10 (36 percent) had undergone thoracic drainage prior to thoracoscopy, 9 (32 percent) presented pneumothorax, and 5 (18 percent) developed bronchopleural fistula. In the no-NP group, the median drainage time and the median length of hospital stay were 6 and 10 days, respectively. CONCLUSIONS: Pneumothorax should raise the suspicion of NP. Early thoracoscopy can be a valuable treatment option for NP in children because it hastens recovery in comparison with the medical treatment alone and avoids extensive late thoracotomy lung resections.

Expanded clinical presentation of community-acquired methicillin-resistant Staphylococcus aureus pneumonia.

BACKGROUND: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has been documented to cause community-acquired pneumonias (CAP), notable for necrotizing features. The frequency of occurrence, risk factors, and optimal treatment of CA-MRSA CAP are unclear. METHODS: This was a retrospective analysis of patients admitted to Northwestern Memorial Hospital from January 2005 to April 2007 with initial clinical presentation of pneumonia and respiratory or blood culture positive for CA-MRSA. Definition of CA-MRSA was based on sensitivity to trimethoprim/sulfamethoxazole and clindamycin. RESULTS: Fifteen patients with CA-MRSA CAP were identified during the 28-month period. Only one of the 14 patients tested had evidence of preceding influenza, and no seasonal pattern was seen. Seven patients were never admitted to the ICU. Eight of 14 with chest CT scans had evidence of lung necrosis. Nine of 15 had evidence of pleural effusions early in their hospital course, and five of nine required at least one pleural drainage procedure. Seven of 15 were immunocompromised (three HIV, one acute lymphocytic leukemia [ALL], one high-dose steroids, and two immunoglobulin deficiency) with an additional three patients with diabetes. Mortality was only 13% (two of 15); both deaths occurred in patients with severe immunocompromise (ALL post chemotherapy and AIDS). Fourteen of 15 patients were treated with antimicrobials that inhibit exotoxin production (clindamycin or linezolid). CONCLUSIONS: CA-MRSA pneumonia is not necessarily a post-influenza infection. Despite necrotizing features in many, the mortality of CA-MRSA pneumonia in our series is lower than previously reported, and patients do not routinely require ICU care. Treatment with antibiotics that inhibit exotoxin production and/or nontoxigenic strains may explain this improved outcome.

Pneumonia estafilocócica adquirida na comunidade / Community-acquired staphylococcal pneumonia

OBJETIVO: A pneumonia estafilocócica geralmente apresenta uma elevada taxa de morbidade e mortalidade. Normalmente ocorre em infecções por influenza (via aerógena) ou durante episódios de bacteremia (via hematogênica). MÉTODOS: Um estudo retrospectivo e descritivo foi realizado com os pacientes que foram admitidos em nosso hospital entre janeiro de 1992 e dezembro de 2003 com diagnóstico de pneumonia adquirida na comunidade causada por Staphylococcus aureus. Todos eles eram maiores de 14 anos e não usuários de drogas endovenosas. RESULTADOS: De um total de 332 casos de pneumonia adquirida na comunidade, foram encontrados 24 pacientes (7,3 por cento) com pneumonia estafilocócica. A idade mínima e máxima eram de, respectivamente, 14 anos e 89 anos. Quinze pacientes eram homens e nove eram mulheres. Doze pacientes preenchiam critérios para pneumonia grave. O radiograma de tórax evidenciou consolidação unilateral em 14 casos, bilateral em 10, derrame pleural em 15, rápida progressão radiológica das lesões pulmonares em 14, presença de cavitação em 6 e pneumotórax em 1 paciente. A maioria dos pacientes apresentou co-morbidades e diabetes mellitus foi a mais freqüente. Doze pacientes apresentaram complicações como empiema e choque séptico. Houve quatro óbitos, o que representou 16,6 por cento da amostra. CONCLUSÕES: A apresentação clínica da pneumonia causada por S. aureus é similar à apresentação das pneumonias originadas por outros agentes etiológicos. Os achados radiológicos, os dados epidemiológicos e os fatores de risco fornecem importantes indícios para o diagnóstico. Estes fatores são importantes para uma suspeição clínica, já que o S. aureus normalmente não é incluído nos tratamentos empíricos.

OBJECTIVE: Staphylococcal pneumonia typically presents high rates of morbidity and mortality. It typically occurs in cases of influenza (airborne transmission) or during episodes of bacteremia (blood-borne transmission). METHODS: A retrospective and descriptive study was conducted in patients admitted to our hospital between January of 1992 and December of 2003. All of he patients included had been diagnosed with community-acquired pneumonia caused by Staphylococcus aureus. All were older than 14 years of age, and none were intravenous drug users. RESULTS: Community-acquired pneumonia was identified in 332 cases, of which 24 (7.3 percent) were identified as cases of staphylococcal pneumonia. Age ranged from 14 to 89 years. Fifteen patients were male, and nine were female. Twelve patients met the criteria for severe pneumonia. Chest X-rays showed unilateral consolidation in 14 cases, bilateral consolidation in 10, pleural effusion in 15, rapid radiological progression of pulmonary lesions in 14, cavitation in 6 and pneumothorax in 1. Most of the patients presented comorbidities, of which diabetes mellitus was the most common. Twelve patients presented complications such as empyema and septic shock. Four patients died, translating to a mortality rate of 16.6 percent in our sample. CONCLUSIONS: The clinical presentation of pneumonia caused by S. aureus is similar to that of pneumonia caused by other etiological agents. Radiological findings, epidemiological data and risk factors provide important clues to the diagnosis. These factors are important for clinical suspicion, since S. aureus is not typically addressed in empirical treatment.

Pneumonia in HIV-infected persons: increased risk with cigarette smoking and treatment interruption.

RATIONALE: Bacterial pneumonia is a major cause of morbidity for HIV-infected persons and contributes to excess mortality in this population. OBJECTIVES: To evaluate the frequency and risk factors for occurrence of bacterial pneumonia in the present era of potent antiretroviral therapy. METHODS: We evaluated data from a randomized trial of episodic antiretroviral therapy. The study, Strategies for Management of Antiretroviral Therapy, enrolled 5,472 participants at 318 sites in 33 countries. Study patients had more than 350 CD4 cells at baseline. Diagnosis of bacterial pneumonia was confirmed by a blinded clinical-events committee. MEASUREMENTS AND MAIN RESULTS: During a mean follow-up of 16 months, 116 participants (2.2%) developed at least one episode of bacterial pneumonia. Patients randomized to receive episodic antiretroviral therapy were significantly more likely to develop pneumonia than patients randomized to receive continuous antiretroviral therapy (hazard ratio, 1.55; 95% confidence interval, 1.07-2.25; P = 0.02). Cigarette smoking was a major risk factor: Current-smokers had more than an 80% higher risk of pneumonia compared with never-smokers (hazard ratio, 1.82; 95% confidence interval, 1.09-3.04; P = 0.02). Participants who were on continuous HIV treatment and were current smokers were three times more likely to develop bacterial pneumonia than nonsmokers. Current smoking status was significant, but a past history of smoking was not. CONCLUSIONS: Bacterial pneumonia is a major source of morbidity, even for persons on potent antiretroviral therapy, including those with high CD4 cells. Efforts to reduce this illness should stress the importance of uninterrupted antiretroviral therapy and attainment and/or maintenance of nonsmoking status.

Infecciones adquiridas en la comunidad por Staphylococcus aureus resistente a meticilina en un hospital de agudos / Community-acquired methicillin-resistant Staphylococcus aureus infections in a hospital for acute diseases

Staphylococcus aureus resistente a meticilina (SAMR) es uno de los principales agentes asociados a infecciones intrahospitalarias; sin embargo, en los últimos años ha surgido como un patógeno emergente de la comunidad, causando infecciones graves, principalmente en jóvenes. Se describen 33 casos de infecciones por SAMR de origen comunitario, diagnosticadas entre mayo de 2005 y junio de 2006 en el HIGA "Eva Perón". Se estudiaron retrospectivamente los aislamientos; se confirmó la resistencia a meticilina mediante la detección del gen mecA, se investigó la presencia de genes que codifican dos factores de virulencia (leucocidina de Panton-Valentine -LPV- y g-hemolisina) y el tipo de casete mec mediante PCR. Todos los pacientes se encontraban sanos previamente. Cuatro pacientes menores de 12 años presentaron bacteriemia, uno con neumonía grave y los 3 restantes con infección osteoarticular; todos los pacientes mayores de 12 años presentaron infecciones de piel y partes blandas sin compromiso sistémico. Se constató la presencia de casete mec tipo IV en todos los aislamientos; la resistencia a meticilina no se acompañó de resistencia a otros antimicrobianos; los aislamientos fueron portadores de genes que codifican para LPV y para g-hemolisina. Es importante considerar la presencia de estas cepas de origen comunitario a fin de elaborar estrategias para su correcto tratamiento.

Methicillin- resistant Staphylococcus aureus (MRSA) is one of the most prevalent pathogens associated with nosocomial infections. However, most recently, MRSA has arisen as an emerging community pathogen, causing serious infections, mainly among young patients. We herein describe 33 cases of infections caused by community-acquired MRSA (CMRSA), diagnosed between May 2005 and June 2006, at "Eva Perón" Hospital. The isolations were retrospectively studied. Methicillin resistance was confirmed by means of the detection of the mecA gene, and the genes for two virulence factors (Panton-Valentine Leucocidin -PVL- and g-haemolysin) as well as the cassette mec type were screened by PCR. All the patients were previously healthy. Four patients under 12, presented bacteremia, one had serious pneumonia, and the three remaining patients had osteoarticular infections; all the patients over 12, had skin and soft tissue infections without systemic damage. The C-MRSA strains harboured cassette mec type IV, and the PVL and g-haemolysin genes. They were methicillin-resistant, with no other associated resistances. It is important to consider the presence of these community- acquired strains in order to develop strategies for their correct treatment.

[Detection of group B streptococcus in the cases died of neonatal pneumonia].

OBJECTIVE: From the 1970s, group B streptococci (GBS) have been widely recognized as an important pathogen in neonatal infectious disease, and it emerged as the leading cause of neonatal morbidity and mortality in the Western world. However, there are few data on the prevalence of neonatal GBS infections in China. The aim of this retrospective study was to estimate whether GBS is an important pathogen in severe neonatal pneumonia, and to develop a method for detection of GBS infections in fatal neonatal pneumonia. METHODS: A total of 234 neonatal cases (0 - 28 days) died in Beijing Children's Hospital from 1953 to 2004 were enrolled in this study. They were divided into two groups. Two hundred cases diagnosed as neonatal pneumonia were assigned to study group and the remaining 34 cases died of neonatal hemolysis or surgical operation without any confirmed infectious diseases were designated as control group. Formalin-fixed, paraffin-embedded lung tissues were used as source for total genomic DNA extraction. PCR and Southern blot analyses were applied to detect GBS specific cfb gene target sequence. And the clinical data of these cases were reviewed as well. RESULTS: In the study group, 52 cases were detected positive for GBS DNA by PCR (26%), 130 cases were positive by Southern blot (65%). In the control group, 1 case was detected positive GBS DNA by PCR (3%), and 6 cases were positive by Southern blot (18%). The positive rate was significantly lower in the control group than that in the study group (PCR, chi(2) = 8.82, P < 0.01; Southern blot, chi(2) = 26.77, P < 0.01). The positive rate in the neonates younger than 7 days (early-onset) was significantly higher than that in neonates older than 7 days (late-onset) (PCR: 37% vs. 13%, chi(2) = 15.537, P < 0.01; Southern blot: 72% vs. 52%, chi(2) = 4.37, P < 0.05). In the positive early-onset cases, 39% of whom were born prematurely (29/74). Out of the 200 cases, 75 had complete clinical data. Neither blood nor lung culture for GBS was performed in any of these cases. But risk factors were identified for 35 cases, such as premature delivery, low birth weight, premature rupture of the membrane and abnormal amniotic fluid. GBS was positive in all these cases. Severe apnea appeared to be a common symptom and was present in most of the early-onset GBS-positive cases, while cough and wheezing were found in most of the late-onset GBS-positive cases. In the control group, one PCR positive case was suffered from malignant teratoma. The other 5 positive cases confirmed by Southern blot were diagnosed as kernicterus, hepatoma, aproctia complicating with cysti-urethral fistula, neonatal physio logical bleeding and aproctia complicated with archo-perineal fistula. CONCLUSION: Group B Streptococcus is an important pathogen in fatal neonatal pneumonia, especially in early-onset cases. southern blot may be a sensitive method to detect GBS infection in archival tissues. In the clinical work, more attention should be paid to the neonates with GBS risk factors. And GBS detection and prevention in neonates should be put into clinical practice.

Staphylococcus aureus bacteremic pneumonia: differences between community and nosocomial acquisition.

OBJECTIVE: The aim of the study was to ascertain the clinical and epidemiologic characteristics of patients with nosocomial or community-acquired Staphylococcus aureus bacteremic pneumonia. METHODS: A prospective study of 134 cases diagnosed between January 1990 and December 1995 was performed. RESULTS: Fifty cases involved primary bacteremic pneumonias, of which 80% were nosocomial (the majority, 72%, in intensive care unit patients, of whom 57% were post-surgery). Of the 84 cases of secondary pneumonia, 36 were non-intravenous drug users (78% nosocomial, of whom 43% were in the intensive care unit), and 48 cases were intravenous drug users (98% community-acquired). CONCLUSIONS: Nosocomial S. aureus bacteremic pneumonia was especially frequent in intensive care unit patients (68.1%), and community-acquired pneumonia in intravenous drug users (72.3%). In non-intravenous drug users, clinical outcome and mortality were similar for nosocomial and community-acquired pneumonia.

[Pleuropulmonary staphylococcal infection in infants, in a hospital environment in Ouagadougou (Burkina Faso)]. / La staphylococcie pleuro-pulmonaire du nourisson en milieu hospitalier à Ouagadougou (Burkina Faso).

We observed 36 cases of pleuropulmonary staphylococcal infection (PPS) in infants aged 0 to 30 months, during a prospective study carried out between April 1st 1995 and March 31 1996 at the Pediatrics Department of Ouagadougou University Hospital. PPS accounted for 0.5% of all hospital admissions and 11.6% of all acute basal respiratory infections in children aged less than 30 months. Slightly more boys than girls were affected, with a sex ratio of 1.2. We identified the classic triad of symptoms: cough-fever-polypnea, associated with abdominal ballooning and a change in general condition. On X rays, the typical images showing parenchymatous bubbles were the second most frequent observation (27.8%) after parenchymatous opacities (69.5%). The most frequently used antibiotics were oxacillin (Bristopen), gentamycin (Gentallin) and cefuroxime-axetil (Zinnat). The prognosis of PPS is poor, with a high mortality rate (27.8%) and a risk of pleural recurrence. Being very young, late hospitalization, malnutrition and leukopenia were identified as factors indicating a poor prognosis. Recygling of health care personnel for the management of acute respiratory infections, a decrease in malnutrition and an improvement in vaccination cover are essential if the mortality and morbidity of acute respiratory infections, and PPS in particular, are to be reduced.