FDG-PET parameters predicting mediastinal malignancy in lung cancer

Background

Staging of mediastinal lymph nodes in non-small cell lung cancer (NSCLC) is mandatory. The maximum Standard Uptake Value (SUVmax) obtained using F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is the best non-invasive technique available for this evaluation, but its performance varies from center to center. The aim of the present study was to identify FDG-PET predictors of mediastinal malignancy that are able to minimize intercenter variability and improve the selection of subsequent staging procedures.

Method

A multicenter study of NSCLC patients staged through FDG-PET and endobronchial ultrasonography with needle aspiration (EBUS-NA) was performed using therapeutic surgery with systematic nodal dissection as gold standard. Intercenter variability and predictive power for mediastinal malignancy of different FDG-PET measures were assessed, as well as the role of these measures for selecting additional staging procedures.

Results

One hundred and twenty-one NSCLC patients, of whom 94 (72%) had ≥1 hypermetabolic spots in the mediastinum, were included in the study. Mean SUVmax of the primary tumor was 12.3 (SD 6.3), and median SUVmax of the highest hypermetabolic spots in the mediastinum was 3.9 (IQR 2.4-7). Variability of FDG-PET measures between hospitals was statistically significant (p = 0.016 and p < 0.001 respectively), but lost significance when SUVmax in the mediastinum was expressed as a ratio or a subtraction from the primary tumor (SUVmax mediastinum/tumor, p = 0.083; and SUVmax mediastinum - tumor, p = 0.428 respectively). SUVmax mediastinum/tumor showed higher accuracy in the ROC analysis (AUC 0.77 CI 0.68-0.85, p < 0.001), and showed predictive power for mediastinal malignancy when using a 0.4 cutoff (OR 6.62, 95%CI 2.98-14.69). Sensitivities and negative predictive values of clinical staging through EBUS-NA attained values ranging between 57% and 92% after FDG-PET, which improved with additional techniques when the tumor had a diameter >3 cm and/or a SUVmax mediastinum/tumor ratio >0.4.

Conclusion

The SUVmax mediastinum/tumor ratio is a good predictor of regional tumor extension in NSCLC. This measure is not influenced by intercenter variability and has an accuracy of over 70% for the identification of malignancy when using a 0.4 cutoff.

First Report of Damping-Off Caused by Cylindrocarpon pauciseptatum on Pinus radiata in Spain

In the fall of 2009, damping-off of Pinus radiata seedlings was observed in a pine nursery in Sant Feliu de Buixalleu, Girona Province, northeastern Spain. Plants exhibited needle blight, extensive root necrosis, and root death. Root sections of symptomatic plants were cut, washed under running tap water, surface disinfected for 1 min in a 1.5% sodium hypochlorite solution, and washed twice with sterile distilled water. Small fragments of discolored tissues were plated onto potato dextrose agar (PDA) supplemented with 0.5 g liter^-1 of streptomycin sulfate. Plates were placed at 25°C in the dark for 10 to 14 days, and all fungal colonies were transferred to PDA. A Cylindrocarpon sp. was consistently isolated from necrotic root tissues. Single-conidial isolates were obtained and grown on PDA and Spezieller Nährstoffarmer agar (SNA) (2) at 25°C for 10 days with a 12-h photoperiod. On PDA, the isolates developed abundant mycelium, which varied from white-to-grayish brown or golden brown. On SNA, all isolates produced two-septate, (35-) 39.4 (-40) × (7.5-) 7.7 (-8.75) μm, and three-septate, (32.5-) 40.9 (-52.5) × (7.5-) 7.7 (-8.75) μm, macroconidia. Microconidia, one-septate macroconidia, and chlamydospores were not observed. Identity of these isolates was determined by a multiplex PCR system using a set of three pair of specific primers (Mac1/MaPa2, Lir1/Lir2, and Pau1/MaPa2) (1), which generated a 117-bp product that was characteristic of Cylindrocarpon pauciseptatum Schroers & Crous. Morphological characteristics also supported this identification (4). Internal transcribed spacers regions (ITS1 and ITS4) of rDNA were obtained for isolate 1052 and deposited in GenBank (Accession No. HQ441248). This sequence was identical (100%) with the sequence of C. pauciseptatum (GenBank Accession No. HM036590). Pathogenicity tests were conducted with inoculum produced on wheat kernels that were soaked in distilled water in flasks for 12 h. Each flask contained 200 ml of kernels that were subsequently autoclaved three times after excess water was drained. Two fungal disks from a 2-week-old culture of C. pauciseptatum (isolate 1052) grown on PDA were placed aseptically in each flask. Cultures in flasks were incubated at 25°C for 4 weeks and shaken once a week. A plastic pot (220 cm³) was filled with a mixture of sterilized peat moss and 10 g of inoculum. A 1-month-old seedling of P. radiata was planted in plastic pots and placed in a greenhouse at 25 to 30°C in a completely randomized design with six replications. Controls contained sterile wheat kernels. The experiment was repeated. Symptoms developed 20 days after inoculation and consisted of root lesions, a reduction in root biomass, needle blight, and the death of all seedlings. The fungus was reisolated from affected seedlings. Damping-off was not observed on the control plants. C. pauciseptatum causing black foot disease of grapevine (3) was first found in Spain in 2008, but to our knowledge, this is the first report of C. pauciseptatum causing damping-off of P. radiata in Spain. References: (1) S. Alaniz et al. Plant Dis. 93:821, 2009. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Oxford, 2006. (3) M. T. Martin et al. Plant Dis. 95:361, 2011. (4) H. J. Schroers et al. Mycol. Res. 112:82, 2008.

Pulmonary nocardiosis: clinical experience in ten cases

BACKGROUND

Pulmonary nocardiosis is an infrequent infection whose incidence seems to be increasing due to a higher degree of clinical suspicion and the increasing number of immunosuppressive factors.

OBJECTIVE

To study the predisposing factors, clinical characteristics, diagnostic procedures, treatment and progress of pulmonary nocardiosis (PN).

METHODS

Review of 10 patients (9 male, 1 female, mean age 61) with PN in a 600-bed teaching hospital, diagnosed from 1992 to 1999.

RESULTS

Associated diseases observed were chronic obstructive pulmonary disease (COPD) in 6 patients, human immunodeficiency virus (HIV) infection in 3 and polymyalgia rheumatica in 1. Four patients had received oral corticotherapy for COPD for over a year (mean dose 13 mg/day of prednisone or equivalent). The main reason for consultation was an increase in dyspnea in the patients with COPD (6/6) and fever in those with HIV (3/3). Mean time between onset of symptoms and diagnosis was 5 weeks. In 8 patients, the infection occurred outside the hospital setting. The infection was restricted to the lung in 9/10; in the remaining case, the central nervous system (CNS) and subcutaneous tissue were affected. Lobar or multilobar consolidation was the most frequent radiographic pattern found (6/10). Sputum culture was positive when performed (8 cases). Diagnosis was made or confirmed by bronchoscopy (bronchoaspirate or protected specimen brush) in 5 patients. Germs isolated were: Nocardia asteroides (8/10), Nocardia farcinica (1/10), Nocardia otitidiscaviarum (1/10). Cotrimoxazole was the most used empirical treatment (6/10). Resolution was achieved in 5 cases. Four subjects died: 1 HIV patient with disseminated nocardiosis, and 3 COPD patients, 2 of whom had received long-term corticotherapy. Illness recurred in only 1 case, due to failure to comply with treatment.

CONCLUSIONS

(1) In our geographical setting Nocardia presents as a subacute or chronic pulmonary infection, mainly outside the hospital. (2) It tends to affect only the lung. (3) Diagnosis requires a high clinical suspicion, and can be made on the basis of a sputum culture. (4) Nocardia tends to attack patients with underlying COPD, or immunodepressed patients treated with glucocorticoids, or patients with HIV infection. (5) Mortality is high in both COPD and HIV patients. (6) In our area, cotrimoxazole seems to be the most commonly prescribed treatment.

Induced sputum in the diagnosis of peripheral lung cancer not visible endoscopically

The diagnosis of small peripheral lung cancer is difficult to achieve by non-invasive methods. We hypothesized that in these patients induced sputum might ncrease the diagnostic yield over spontaneous sputum, representing a good diagnostic alternative in selected patients. We prospectively evaluated 60 patients with peripheral lung lesions and normal bronchoscopic evaluation. Six samples of sputum (three spontaneous and three induced with nebulization of hypertonic saline) before bronchoscopy and six samples of sputum after bronchoscopy (three spontaneous and three induced) were obtained in each subject. Forty-two out of the 60 patients included were finally diagnosed with lung cancer. Eighteen patients were diagnosed with different benign conditions of the lung. Overall, malignant cells in sputum were observed in 21 patients and in all but one, the final diagnosis of lung cancer was achieved. Only one patient with a pseudoinflammatory tumour of the lung had a false-positive result in one spontaneous sputum sample. The diagnosis of lung cancer was obtained in 18 patients with the induced sputum (43%) and in 14 patients with spontaneous sputum (31%) (P=NS). Samples of induced sputum were more adequate for cytological analysis than samples of spontaneous sputum (P < 0.001). Of 13 patients with peripheral lung neoplasms of 2 cm or less in diameter, five were diagnosed using induced sputum (38%) and only one using spontaneous sputum (8%) (P<0.05). In conclusion, induced sputum is a valuable technique for the diagnosis of peripheral lung cancer. Induced sputum gives better quality specimens and better diagnostic yield in small lesions than the spontaneous sputum and may be indicated in selected patients with disseminated disease, inoperability or severe co-morbities.

Systemic inflammatory response after bronchoalveolar lavage in critically ill patients

Bronchoscopic bronchoalveolar lavage (BAL) may be followed by a systemic inflammatory response. Previous reports have suggested pneumonia as a predisposing condition and systemic cytokines as possible mediators. To test this hypothesis, systemic levels of interleukin (IL)-1beta, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were studied before and at 12 h and 24 h after bronchoscopically guided BAL in 30 mechanically ventilated patients (median age 67 (range 54-76) yrs, simplified acute physiology score II (SAPS II) 33 (12-56)), 20 of whom had pneumonia and 10 of whom were control patients without pneumonia. Arterial oxygen partial pressure to inspired oxygen fraction ratio (Pa,O2/FI,O2), body temperature, mean arterial pressure, and cardiac frequency were recorded. The majority of patients (28/30, 93%) received antibiotic treatment prior to the procedure. Pa,O2/FI,O2 ratio was lower at 12 h compared to baseline in patients with pneumonia (baseline median 192 (range 65-256); 12 h 160 (66-190) mmHg, p<0.001) and ventilated controls (baseline 293 (205-473); 12 h 226 (153-330) mm Hg p=0.011), but returned to baseline levels at 24 h (pneumonia: 194 (92-312), p=0.991; controls: 309 (173-487) mmHg, p=0.785). No changes in other clinical variables were observed. Systemic TNF-alpha levels before BAL (pneumonia: 35 (10-88); controls: 17 (0-33) pg x mL(-1)) did not increase at 12 h (pneumonia: 35 (0-64); p=0.735; controls: 16 (0-21) pg x mL(-1), p=0.123 comparison to baseline) or 24 h (pneumonia: 31 (0-36), p=0.464; controls: 19 (0-43) pg x mL(-1), p=0.358). No changes of IL-1beta (baseline: pneumonia 0 (0-13); controls 1 (0-32) pg x mL(-1)) or IL-6 (baseline: pneumonia, 226 (9-4300); controls, 53 (0-346) pg x mL(-1)) were detected. No deterioration of clinical variables and no increase in systemic cytokine release has been observed after bronchoalveolar lavage, in critically ill patients. The potential cytokine increase is probably too small, in relation to the pre-existing inflammatory response, to yield clinical significance in this population otherwise antibiotic therapy may have been protective.

Comparison of systemic cytokine levels in patients with acute respiratory distress syndrome, severe pneumonia, and controls

BACKGROUND

The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia.

METHODS

Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested.

RESULTS

Serum TNF-alpha levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1beta and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1beta: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1beta: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1beta: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-alpha (standardised coefficient beta = 0.410, p<0.001) and IL-1beta (standardised coefficient beta = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model.

CONCLUSIONS

Serum TNF-alpha levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-alpha and IL-1beta reflect the severity of the lung injury rather than the diagnosis.

Cytokine expression in severe pneumonia: a bronchoalveolar lavage study

OBJECTIVE

To assess the cytokine expression (tumor necrosis factor-alpha [TNF-alpha], interleukin [IL]-1beta, and IL-6) in severe pneumonia, both locally (in the lungs) and systemically (in blood).

DESIGN

Prospective sequential study with bronchoalveolar lavage (BAL) and blood sampling.

SETTING

Six-bed respiratory intensive care unit of a 1,000-bed teaching hospital.

PATIENTS

Thirty mechanically ventilated patients (>48 hrs) were allocated to either the pneumonia group (n = 20) or a control group (n = 10).

INTERVENTIONS

Protected specimen brush and BAL samples for quantitative cultures, and serum and BAL fluid TNF-alpha, IL-1beta, and IL-6 levels were measured on days 1, 3, and 7. In the control group, the procedure was done on day 1 only.

MEASUREMENTS AND MAIN RESULTS

Serum TNF-alpha levels were significantly higher in patients with pneumonia compared with controls (35 +/- 4 vs. 17 +/- 3 pg/mL, respectively, p = .001). IL-6 levels in serum and BAL fluid were higher in pneumonia than in control patients (serum, 837 +/- 260 vs. 94 +/- 35 pg/mL, respectively, p = .017; BAL fluid, 1176 +/- 468 vs. 234 +/- 83 pg/mL, respectively, p = .05). On days 1, 3, and 7 in patients with pneumonia, IL-1beta levels turned out to be higher in BAL fluid than in serum (71 +/- 17 vs. 2 +/-1 pg/mL on day 1; 49 +/- 8 vs. 6 +/- 2 pg/mL on day 3; and 47 +/- 16 vs. 3 +/- 2 pg/mL on day 7 for BAL fluid and serum, respectively, p < .05). No significant correlation between BAL fluid cytokine levels and lung bacterial burden was shown in presence of antibiotic treatment. Although no clear relationship was found between BAL fluid and serum cytokines and mortality, there was a trend toward higher serum IL-6 levels in nonsurvivors (1209 +/- 433 pg/mL) with pneumonia compared with survivors (464 +/- 260 pg/mL). In addition, serum TNF-alpha and IL-6 correlated with multiple organ failure score (r2 = .36, p = .004 for both) and with lung injury score (r2 = .30, p = .01, and r2 = .22, p = .03, for TNF-alpha and IL-6, respectively).

CONCLUSIONS

The present study describes the lung and systemic inflammatory response in severe pneumonia. The lung cytokine expression seems to be independent from the lung bacterial burden in the presence of antibiotic treatment. Because of the limited sample size, we did not find a clear relationship between serum and BAL fluid cytokine levels and outcome.

Role of glucocorticoids on inflammatory response in nonimmunosuppressed patients with pneumonia: a pilot study

The aim of the study was to assess the potential role of glucocorticoids (GC) in modulating systemic and pulmonary inflammatory responses in mechanically ventilated patients with severe pneumonia. Twenty mechanically ventilated patients with pneumonia treated at a respiratory intensive care unit (RICU) of a 1,000-bed teaching hospital were prospectively studied. All patients had received prior antimicrobial treatment. Eleven patients received GC (mean+/-SD dose of i.v. methylprednisolone 677+/-508 mg for 9+/-7 days), mainly for bronchial dilatation. Serum and bronchoalveolar lavage fluid (BALF) tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and C-reactive protein levels were measured in all patients. The inflammatory response was attenuated in patients receiving GC, both systemically (IL-6 1,089+/-342 versus 630+/-385 pg x mL(-1), p=0.03; C-reactive protein 34+/-5 versus 19+/-5 mg x L(-1), p=0.04) and locally in BALF (TNF-alpha 118+/-50 versus 24+/-5 pg x mL(-1), p= 0.05; neutrophil count: 2.4+/-1.1 x 10(9) cells x L(-1) (93+/-3%) versus 1.9+/-1.8 x 10(9) cells x L(-1) (57+/-16%), p=0.03). Four of the 11 (36%) patients receiving GC died compared to six (67%) who were not receiving GC (p=0.37). The present pilot study suggests that glucocorticoids decrease systemic and lung inflammatory responses in mechanically ventilated patients with severe pneumonia receiving antimicrobial treatment.

Pulmonary function tests and CT scan in the management of idiopathic pulmonary fibrosis

Relationships between pulmonary function testing and high-resolution computed tomography (HRCT) were studied in 39 untreated patients with idiopathic pulmonary fibrosis (IPF) at diagnosis, 23 of whom were followed during 7.5 +/- 0.3 mo (mean +/- SEM). At diagnosis, the extent of overall lung involvement in the HRCT scans showed a moderate but significant correlation only with FVC (r = -0.46, p = 0. 003) and DLCO (r = -0.40, p = 0.03). The extent of ground glass pattern also correlated with FVC (r = -0.58, p = 0.0001). Arterial PO2 at peak exercise (n = 13 patients) showed a significant association with the extent of both ground-glass pattern and overall lung involvement in HRCT (r = -0.60, p = 0.02; and r = -0.64, p = 0. 01, respectively). On multivariate analysis a significant independent correlation between the global disease extent in HRCT and both FVC and DLCO was observed. Changes over time in the total extent of the disease evaluated with HRCT scans were also related to those observed in DLCO and in FVC (r = -0.57, p = 0.01, and r = -0. 51, p = 0.01, respectively). The present study suggests that FVC and DLCO are the physiological variables that best reflect the global extent of disease in IPF and thus may provide significant information for the assessment of the disease's progression.

Gastric intramucosal acidosis in mechanically ventilated patients: role of mucosal blood flow

OBJECTIVE

To investigate whether gastric intramucosal acidosis is associated with a decreased gastric mucosal blood flow in mechanically ventilated patients.

DESIGN

Prospective, clinical investigation.

SETTING

University hospital intensive care unit.

PATIENTS

Seventeen mechanically ventilated patients with stable hemodynamic status.

INTERVENTIONS

Gastric tonometry and endoscopic assessment of mucosal blood flow.

MEASUREMENTS AND MAIN RESULTS

Six patients had gastric intramucosal acidosis (intramucosal pH [pHi] of 7.24 +/- 0.06), whereas the remaining 11 patients had pHi values within the normal range (7.44 +/- 0.01). No differences were found between intramucosal acidotic and nonacidotic patients with respect to their general and hemodynamic characteristics. Patients with intramucosal acidosis had a lower gastric mucosal blood flow, as assessed by laser-Doppler flowmetry, than nonacidotic patients (1.4 +/- 0.1 vs. 2.1 +/- 0.2 volts, respectively; p < .05). Reflectance spectrophotometry disclosed that patients with low gastric pHi had also a significantly (p < .05) lower hemoglobin content index (61 +/- 4 arbitrary units) than patients with normal pHi (81 +/- 3 arbitrary units), whereas oxygen saturation index was similar for both groups.

CONCLUSION

Our results support the hypothesis that gastric mucosal hypoperfusion underlies the development of intramucosal acidosis in mechanically ventilated patients.

Lung inflammatory response in pneumonia

In normal conditions, alveolar macrophages (AMs) are the main cells that respond to bacteria that reach lower airways. However, if the microbial inoculum is too high or too virulent to be stopped by AM alone, these cells recruit polymorphonuclear neutrophils (PMN) into the alveoli from the vascular compartment. Cytokines, such as tumour necrosis factor-alpha (TNF-alpha), interleukin-1-beta (IL-beta), interleukin-6 (IL-6), and interleukin-8 (IL-8), secreted by the AM are able to attract PMN enhanced for phagocytosis, ready to destroy the invading pathogens. However, excessive cytokine production has deleterious effects, with a systemic inflammatory response (sepsis) that can lead to multiorganic failure and death. Other cytokines, such as interleukin-10 (IL-10) balance this response, attenuating several inflammatory mechanisms. The inflammatory lung response in pneumonia has been well studied in animals, and more recently in humans, using bronchoalveolar lavage to measure some inflammatory mediators (TNF-alpha, IL-1 beta, IL-6, IL-8). From these studies, it seems that: 1) the inflammatory response to pneumonia is compartmentalized for most cytokines (in contrast to adult respiratory distress syndrome (ARDS)), except for IL-6 which is a general marker of inflammation. On the other hand, C-reactive-protein is an acute-phase protein synthesized by the liver through the stimulus of IL-6 that may also be an easy-to-measure marker of inflammation that is directly related to IL-6; 2) some of these cytokines may be useful as prognostic indices; 3) there is no clear relationship between the local lung bacterial burden and the intensity of the inflammatory response; and 4) the administration of granulocyte colony-stimulating factor (G-CSF) is a promising therapeutic approach that is still under clinical investigation. In the future, it is probable that the therapeutic goal in severe pneumonia will be to find the exact point at which inflammation is beneficial but not deleterious. The measurement of the inflammatory response may serve for this purpose.

Relationship between ventilator-associated pneumonia and intramucosal gastric pHi: a case-control study

PURPOSE

Prior investigations have suggested a clear relationship between nosocomial pneumonia and intramucosal gastric pH (pHi), a probable marker of bacterial translocation.

METHODS

We studied 33 patients (18 with pneumonia and 15 without) admitted to an intensive care unit and hospitalized longer than 72 hours with the aim of assessing the relationship between nosocomial pneumonia, pHi, and outcome. pHi was estimated at the time of inclusion of patients into the study. Arterial pH (pHa) and bicarbonate and stomach pH and tonometer PtCO2 were also recorded. Values of < 7.32 or delta pHa-pHi of > +0.06 were used to differentiate between normal and low pHi. Quantitative cultures of pharyngeal swabs, gastric lumen, and protected specimen brush from lower airways were also done.

RESULTS

The mean pHi values were 7.397 +/- 0.105 (range, 7.14 to 7.53) and 7.452 +/- 0.059 (range, 7.37 to 7.56) for patients with and without pneumonia, respectively (P = .073). Five patients, all with pneumonia, had pHi < 7.32. No patients without pneumonia had pHi < 7.32 (P = .04). The mean delta pHa-pHi was 0.04 +/- 0.07 (range, -0.11 to 0.13) and 0.05 +/- 0.09 (range, -0.09 to 0.28; P = .72) for patients with and without pneumonia, respectively. However, there were significant differences when tonometer PtCO2 values of both groups were compared (38.9 +/- 8.3 and 30.6 +/- 4.7 mm Hg, respectively; P = .025). Patients with pneumonia had higher alkaline gastric lumen pH (5.2 +/- 1.0) than those without pneumonia (3.8 +/- 1.4; P = .006). Nonsurvivors (n = 7) had more acidic pHi (7.33 +/- 0.11) than survivors (7.44 +/- 0.06; P = .045). The mean gastric lumen bacterial concentration was 4.14 +/- 1.01 Log10 CFU/mL in patients with pneumonia and 4.28 +/- 1.22 Log10 CFU/mL in patients without pneumonia (P = NS). When patients with and without intramucosal gastric acidosis (pHi < 7.32) were compared, the gastric bacterial burden was 4.42 +/- 0.82 Log10CFU/mL and 4.32 +/- 1.03 Log10 CFU/mL (P = .08), respectively.

CONCLUSIONS

Most patients with nosocomial pneumonia had no associated intramucosal gastric acidosis. However, low pHi was associated with increased mortality.

Stomach as a source of colonization of the respiratory tract during mechanical ventilation: association with ventilator-associated pneumonia

The aetiopathogenesis of ventilator-associated pneumonia (VAP) requires abnormal oropharyngeal and gastric colonization and the further aspiration of their contents to the lower airways. VAP develops easily if aspiration or inoculation of microorganisms occur in patients with artificial airways, in whom mechanical, cellular and/or humoral defences are altered. Well-known risk factors for gastric colonization include: alterations in gastric juice secretion; alkalinization of gastric contents; administration of enteral nutrition; and the presence of bilirubin. However, the role of the colonized gastric reservoir in the development of VAP remains debatable. Evidence in favour of the role of the stomach in the development of VAP comes mainly from randomized, controlled trials of selective gut decontamination and stress ulcer prophylaxis in the intensive care unit (ICU), in which reducing the bacterial burden of the stomach decreases the incidence of nosocomial respiratory infections. However, at least three studies of flora have found an absence of stomach origin of pneumonia occurring during mechanical ventilation. Prophylactic measures suggested to prevent VAP in relation to the gastric reservoir include: treatment for stress ulcers with sucralfate; prevention of duodenal reflux with metoclopramide; reduction of gastric burden and bacterial translocation by selective digestive decontamination; acidification of enteral feeding; and jejunal feeding. Gastro-oesophageal reflux can be prevented by using small bore nasogastric tubes and jejunal feeding. The aspiration of gastric contents can be reduced by positioning patients in a semirecumbent position, checking the patency of the tube cuff, and aspiration of subglottic secretions. The role of the stomach as a reservoir for microorganisms causing ventilator-associated pneumonia is still controversial but despite the debate, there is major evidence in the literature in favour of the gastric origin of part of these pulmonary infections.

Markers of ventilator-associated pneumonia

The diagnosis of ventilator-associated pneumonia (VAP) is difficult for several reasons. Firstly, clinical markers show a large percentage of false-positive and false-negative results. Secondly, microbiological diagnosis based on quantitative cultures of protected specimen brush (PSB), bronchoalveolar lavage (BAL), and endotracheal aspirates also present false-positive and false-negative results. Furthermore, definite results are delayed for 48-72 hours. For all these reasons it would be an advantage to have a biological marker of ventilator-associated pneumonia in clinical practice. Since clinical features of pneumonia in mechanically ventilated patients are neither specific nor sensitive, rapid markers of pneumonia might be of great assistance to the clinician in deciding whether to start an empiric antibiotic regimen. A marker of ventilator-associated pneumonia could be a rapid alternative diagnostic method which permits the definite diagnosis of pneumonia. Accordingly, specific markers of VAP, namely the presence of intracellular microorganisms, the detection of elastin fibres, the antibody-coated bacteria test, the level of endotoxin in bronchoalveolar lavage fluid, the local production of interleukin-8, the levels of lactate dehydrogenase, and decreased surfactant protein A, may be important as they can provide a rapid diagnosis of VAP. Among the markers alluded to above, the search for intracellular bacteria in polymorphonuclear leukocytes or macrophages is the most widely validated technique with an excellent specificity, provided that prior antibiotics are not given. However, this technique has its own limitations; it requires a considerable time effort for the microbiologist, and also compels the performance of BAL, a technique not always harmless to the patient.

The role of the gastric reservoir in ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a common complication of mechanical ventilation with an incidence ranging from 9-70% and averaging around 25%. The pathogenesis of VAP requires abnormal oropharyngeal and gastric colonisation and then aspiration of these contents into the lower airways. Another co-existing mechanism could be direct oropharyngeal or lower airways inoculation of microorganisms through contaminated respiratory therapy equipment. Ventilator-associated pneumonia develops easily if aspiration or inoculation of microorganisms occur in patients with artificial airways and in whom mechanical, cellular and/or humoral defences are altered. Both host factors and treatments may alter pulmonary defence mechanisms; these too may contribute to the development of VAP. An alternative mechanism to explain VAP is bacterial translocation, although this mechanism is still under investigation. Figure 1 illustrates a schema of the pathogenesis of VAP. In this paper we review the possible role of the gastric reservoir in the aetiology of VAP, emphasising the following issues: 1. Risk factors for gastric colonisation 2. Clinical evidence of gastric aspiration to the lower airways in mechanically ventilated patients 3. Clinical evidence and controversies surrounding the role of the gastric reservoir in ventilator-associated pneumonia 4. The role of bacterial translocation as a mechanism for the development of VAP 5. A summary of prophylactic measures.

[A decrease in the level of CPAP required after prolonged treatment in patients with the obstructive sleep apnea syndrome]

Application of continuous positive upper airway pressure (CPAP) is the treatment of choice in obstructive sleep apnea syndrome (OSAS). CPAP keeps the upper airway open by providing a "pneumatic splint" on the pharyngeal walls. However, it has been suggested that prolonged nasal CPAP treatment may also improve the physiopathological mechanisms responsible for OSAS by a variety of mechanisms such as the reduction of edema of the pharyngeal mucosa, modification of upper airway muscle dynamics; there may even be a reduction in the intensity of phenomena responsible for brief awakening and ending of apneic episodes. The objective of this study was to determine whether prolonged nasal CPAP is associated to a reduction of CPAP pressure required for eliminating apnea in patients with OSAS. We studied 22 patients (4 women) with OSAS diagnosed by conventional polysomnography, including study of neurological variables during sleep (electroencephalogram, ocular movement, submental electromyogram), respiratory variables (nasal air flow, thoracic-abdominal movement, O2 saturation in the blood), and others (electrocardiogram, leg movement). Treatment was exclusively with nasal CPAP. All 22 patients were middle-aged (52.3 +/- 10 years), presented a mean apnea/hypoapnea index of 65.2 +/- 24 per hour. CPAP levels needed to eliminate episodes of apnea, blood O2 desaturation and snoring at the time of diagnosis and after long-term treatment (8.5 +/- 4.6 months) were applied. Weight was recorder at both measurement times. Eighteen of the 22 patients (1 woman, mean age 53.1 +/- 11.4 years and apnea/hypopnea index 64.8 +/- 23.4 per hour) experienced no weight change during treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

[Anxiety scales and Goldberg's depression: an efficient interview guide for the detection of psychologic distress]

OBJECTIVES

Validation of Goldberg's Anxiety and Depression scales in our settings.

DESIGN

Transverse study. Two phases screening at population previously stratified and randomly allocated. SITE. National Health Institute's Primary Care Centres at the city of Zaragoza.

PATIENTS AND OTHER PARTICIPANTS

444 patients, aged 19 and older, who attend their general practitioner for a new episode of illness. The sample has been previously stratified by sex and age.

MEASUREMENTS AND MAIN RESULTS

At the first stage the sample has been studied with a Health Survey consisting of a variety of sound validity (General Health Questionnaire-28 items version, spanish version of Folstein's mini Mental Status Examination, CAGE and another drug and over the counter products screening questionnaire) and the new scales, that we attempt to validate. At the second stage "the possible cases" chosen at the first phase and 10% of possible non cases are assessed with a comprehensive Psychiatric Interview: EPEP (Standardized Polyvalent Psychiatric Interview).

CONCLUSIONS

The new scales E.A.D.G. have supported their validity for the screening of the most prevalent psychiatric disturbances in primary care settings. Their validity for the screening of the most prevalent psychiatric disturbances in primary care settings. They have outstanding and promising advantages when compared to traditional methods: brevity, simplicity, discriminatory ability between anxiety and depression and usefulness as an interview guideline.

[Epidemic Kaposi's sarcoma in women: presentation of 4 cases]

Epidemic Kaposi's sarcoma is the neoplasm most frequently manifested in infection by the human immunodeficiency virus. Its prevalence is considerably higher among homosexual males than among intravenous drug users with practically exclusive infection in this sex. Four cases of Kaposi's sarcoma in women with the human immunodeficiency virus are described. Two of these subjects were intravenous drug users and the other two were heterosexually promiscuous as the only conduct of risk for acquiring infection by the human immunodeficiency virus. Kaposi's sarcoma was the form of presentation of the syndrome of acquired immunodeficiency syndrome in these four patients.