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B Misset

Publications and source records attributed to B Misset.

36 records · Page 2Linked to original sources
PubMed1994

Super-high-risk germ-cell tumors: a clinical entity. Report of eleven cases.

Among patients suffering from nonseminomatous germ-cell tumor, with a poor prognosis, a subset underwent respiratory failure and died very early in the course of their treatment. Between 1982 and 1989, 11 out of 56 such patients (20%) died within the first 5 weeks of chemotherapy. The clinical, radiological, biological and infectious characteristics of these patients were analyzed. Nine patients had extensive pulmonary metastases and the 2 others presented a bulky mediastinal mass with pleural effusion. All patients experienced acute respiratory distress during chemotherapy and underwent mechanical ventilation. All patients were febrile, and septicemia was documented in 7 cases. WHO grade 4 and grade 1-2 renal toxicities occurred in 3 and 4 patients respectively. There was no tumor lysis syndrome. All patients died within 35 days from the start of therapy; 4 were autopsied. These 11 patients represent a clinical entity, having what we called super-high-risk germ cell tumors. Early death is related to pulmonary distress within the first 5 weeks of therapy. The origin of the pulmonary distress is multifactorial: bulky disease of the chest, infection, and interstitial fibrosis. Immediate full-dose standard chemotherapy in association with intensive supportive care is recommended in the management of these patients.

Adult↗
PubMed1994

Mechanisms of failure to decontaminate the gut with polymixin E, gentamicin and amphotericin B in patients in intensive care.

The objective of the present work was to assess the possible mechanisms of the poor efficiency of selective decontamination of the digestive tract (SDD) in medical and surgical intensive care unit (ICU) patients. Sixty-four consecutive mechanically ventilated patients received gut decontamination with polymixin E, gentamicin and amphotericin B via a nasogastric tube and were assessed for oropharyngeal, gastric and fecal colonization and for the presence of each antibiotic in the stomach and feces. A decrease in fecal colonization with Escherichia coli was observed over 20 days but not with other gram-negative bacteria or gram-positive cocci. Fifteen and 26% of the fecal colonizing gram-negative bacteria were resistant to polymixin E and gentamicin, respectively, at admission. These proportions increased to up to 50% after 16 days of treatment. Although 50% of staphylococci were initially sensitive to gentamicin, all strains were resistant to this drug after four days of SDD. Both antibiotics were found in concentrations of less than 20 micrograms/g in 11 of 38 stools. Of these 38 stools, nine were not contaminated, 20 were colonized with resistant bacteria and 16 with strains sensitive to one antibiotic present in the stool. Therefore, the poor efficiency of gut decontamination observed was probably due to the great proportion of resistant strains on admission of the patients, to the selection of such resistant strains with SDD, to poor intestinal transit of the antibiotics, and to inactivation of the drugs by the feces. These results support stringent monitoring of fecal colonization in patients undergoing SDD in order to detect the fecal carriage of gram-positive and multiresistant gram-negative bacteria.

Adult↗
PubMed1994

Circulating interleukin-8 concentrations in patients with multiple organ failure of septic and nonseptic origin.

OBJECTIVES: Interleukin (IL)-8, a pro-inflammatory cytokine, is a potent chemoattractant factor and an activator of neutrophils produced by many cell types after stimulation by IL-1, tumor necrosis factor (TNF), or microbial products such as endotoxins. We investigated whether the presence of measurable IL-8 in plasma was associated with the clinical status of severely ill septic or nonseptic patients susceptible to the development of multiple organ failure. DESIGN: Cohort study. SETTING: A collaborative study between an intensive care unit and a research laboratory. SUBJECTS: Circulating IL-8 concentrations were measured in the plasma of 27 patients with sepsis syndrome and in 16 patients with noninfectious shock because these two conditions put patients at risk for the development of multiple organ failure. Sixteen of 27 patients with severe infection and 13 of 16 patients with noninfectious pathologies developed multiple organ failure. MEASUREMENTS AND MAIN RESULTS: A specific enzyme-linked immunosorbent assay (ELISA) for IL-8 was set up with a monoclonal and a rabbit polyclonal antihuman IL-8 using a sandwich technique. High concentrations of circulating IL-8 were found in the plasma of patients with sepsis syndrome. Among septic patients, a significant difference was observed between concentrations of IL-8 in survivors (n = 16) and nonsurvivors (n = 11) (81 +/- 13 pg/mL vs. 3326 +/- 1219 pg/mL, respectively; p = .001). A correlation was noticed between plasma IL-8 and IL-6 concentrations (r2 = .42; p = .001), while no correlation was observed between IL-8 and TNF-alpha values, or between IL-8 and IL-1 beta. Although the mortality rate of nonseptic, multiple organ failure patients was 92%, low plasma concentrations of IL-8 were found (78 +/- 34 pg/mL), while high plasma concentrations were measured in septic, multiple organ failure patients (mortality rate 69%) who were sampled at a similar stage. By contrast, increased IL-6 values were observed in both septic and nonseptic, multiple organ failure patients. CONCLUSIONS: In septic patients, high amounts of circulating IL-8 concentrations correlate with fatal outcome, whereas only low plasma concentrations of IL-8 are present in patients with nonseptic, multiple organ failure. This finding suggests that the signals involved in the exacerbation of IL-8 production are different, depending on infectious or noninfectious etiology.

Aged↗
PubMed1993

Expression of tumor necrosis factor-alpha gene in alveolar macrophages from patients with the adult respiratory distress syndrome.

The adult respiratory distress syndrome (ARDS) is a complex syndrome in which pathogenesis is multifactorial. TNF-alpha, known to be pivotal in tissue damage, has been shown to have high levels in blood and alveolar fluid in ARDS. The identification of the cells responsible for this production in the alveolar milieu has not yet been reported. In order to evaluate the TNF-alpha gene expression in ARDS we have analyzed by in situ hybridization, using RNA probes, alveolar macrophages (AM) obtained by BAL from seven patients with ARDS, eight patients with miscellaneous respiratory diseases, and three control patients. In freshly collected AM from patients with ARDS, 66 +/- 14.5% cells expressed the TNF-alpha gene without in vitro stimulation. This TNF-alpha expression does not result from the BAL procedure itself since only a few unstimulated control AM contained TNF-alpha mRNA transcripts. TNF-alpha expression in AM is not restricted to patients with ARDS since it has also been observed in miscellaneous respiratory diseases; however, this expression is a constant feature in ARDS. These results demonstrated the major role of AM in the intra-alveolar production of TNF-alpha, and they point out the necessity in ARDS for a specific intra-alveolar therapy.

Adult↗
PubMed1993

Is protected specimen brush a reproducible method to diagnose ICU-acquired pneumonia?

UNLABELLED: Protected specimen brush (PSB) is considered to be one of the standard methods for the diagnosis of ventilator-associated pneumonia, but to our knowledge, intraindividual variability in results has not been reported previously. PURPOSE: To compare the results of two PSB performed in the same subsegment on patients with suspected ICU-acquired pneumonia (IAP). STUDY DESIGN: Between October 1991 and April 1992, each mechanically ventilated patient with suspected IAP underwent bronchoscopy with two successive PSB in the lung segment identified as abnormal on radiographs. Results of the two PSB cultures were compared using 10(3) cfu/ml cutoff for a positive result. Four definite diagnoses were established during the follow up: definite pneumonia, probable pneumonia, excluded pneumonia, and uncertain pneumonia. POPULATION: Forty-two episodes in 26 patients were studied; 60 percent of patients received prior antibiotic therapy. Thirty-two microorganisms were isolated from 24 pairs of PSB. Definite diagnosis was definite pneumonia in 7, probable pneumonia in 8, excluded pneumonia in 17, and uncertain pneumonia in 10 cases. RESULTS: The PSB recovered the same microorganisms and argued for a good qualitative reproducibility. The distinction of positive and negative results on the basis of the 10(3) cfu/ml classic threshold was less reproducible. For 24 percent of the microorganisms recovered and in 16.7 percent of episodes of suspected IAP, the two consecutive samples gave results spread out on each side of the 10(3) cfu/ml cutoff. Discordance was higher when definite diagnosis was certain or probable than when diagnosis was excluded (p = 0.015). There was no statistical effect of the order of samples between the two specimens for bacterial index and microorganism concentrations. CONCLUSION: These findings argue for the poor repeatability of PSB in suspected IAP and question the yield of the 10(3) cfu/ml threshold. In attempting to diagnose IAP, the results of PSB must be interpreted with caution considering the intraindividual variability.

Bacteriological Techniques↗
PubMed1992

Circulating cytokines: the tip of the iceberg?

Circulating cytokines, particularly TNF alpha, IL-1, IL-6 and IL-8, can be detected during severe infections consecutively to an exacerbate release by activated cells. The presence or absence of cytokines within biological fluids reflects a rather complex balance between enhancing and inhibitory signals acting on producer cells, between production and catabolism, and between their binding to the target cells and the modulation of their receptors on the cell surface. Furthermore, their presence does not necessarily parallel their activity and a possible interplay between the cytokines and their corresponding inhibitors should be considered. On the contrary, the absence of detectable circulating cytokines does not indicate an absence of production by activated cells. We discuss the concept that circulating cytokines represent the tip of the iceberg.

Animals↗
PubMed1991

Dissociation between plasma and monocyte-associated cytokines during sepsis.

We report our investigations of circulating interleukin (IL) 1 beta, IL 6 and tumor necrosis factor (TNF)-alpha, as well as cell-associated IL 1 alpha, IL 1 beta and TNF-alpha in plasma and monocytes of 21 patients with sepsis syndrome and 6 patients with non-septic shock. Longitudinal studies reveal that (a) the most frequent detectable plasma cytokines were TNF-alpha and IL 6, (b) the presence and the kinetics of circulating cytokines were independent of one other, (c) detectable levels of cytokines could be found for a long period of time, and (d) significantly higher levels of IL 6 were found for non-surviving patients. Because of the in vivo half-life of cytokines and of the existence of numerous specific high-affinity receptors, it is quite probable that detectable plasma cytokines represent the excess of produced mediators which have not been trapped by the target cells. TNF-alpha (410 +/- 65 pg/10(6) monocytes) and IL 1 beta (153 +/- 60 pg/10(6) monocytes) were frequently found associated to monocyte lysates (88% and 50%, respectively). Despite the fact that IL 1 alpha is the most abundant cytokine found associated to monocytes following in vitro activation, IL 1 alpha was rarely found in monocytes of intensive care unit patients (29%). No correlation was found to exist between the levels of plasma cytokines and cell-associated cytokines. Some patients had plasma TNF-alpha or IL 1 beta in the absence of the corresponding monocyte-associated cytokine. This observation suggests that cells other than monocytes can participate in the production of circulating cytokines. At the end of the longitudinal study (day 14 +/- 2), only 2/12 surviving patients still had plasma TNF-alpha, whereas 8/12 had monocyte-associated TNF-alpha. These results indicate that activation of monocytes still occurs in patients for whom no plasma cytokines can be detected. Thus, in addition to the measurement of plasma cytokine, measurement of cell-associated cytokine appears useful to assess cytokine production and monocyte activation in vivo.

Bacterial Infections↗
PubMed1991

Wegener's granulomatosis presenting as diffuse pulmonary hemorrhage.

A 35-year-old woman experienced diffuse intraalveolar haemorrhage with respiratory distress and acute renal failure. Renal histology and evolution confirmed Wegener's granulomatosis. Early use of immunosuppressive drugs allowed weaning from mechanical ventilation and temporary improvement of the renal failure. A review of the literature emphasizes the rarity of alveolar hemorrhage as an initial symptom of Wegener's granulomatosis and the necessity of aggressive management.

Adult↗
PubMed1991

Dysregulation of in vitro cytokine production by monocytes during sepsis.

The production by monocytes of interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF alpha) in intensive care unit (ICU) patients with sepsis syndrome (n = 23) or noninfectious shock (n = 6) is reported. Plasma cytokines, cell-associated cytokines within freshly isolated monocytes and LPS-induced in vitro cytokine production were assessed at admission and at regular intervals during ICU stay. TNF alpha and IL-6 were the most frequently detected circulating cytokines. Despite the fact that IL-1 alpha is the main cytokine found within monocytes upon in vitro activation of cells from healthy individuals, it was very rarely detected within freshly isolated monocytes from septic patients, and levels of cell-associated IL-1 beta were lower than those of TNF alpha. Cell-associated IL-1 beta and TNF alpha were not correlated with corresponding levels in plasma. Upon LPS stimulation, we observed a profound decrease of in vitro IL-1 alpha production by monocytes in all patients, and of IL-1 beta, IL-6, and TNF alpha in septic patients. This reduced LPS-induced production of cytokines was most pronounced in patients with gram-negative infections. Finally, monocytes from survival patients, but not from nonsurvival ones recovered their capacity to produce normal amounts of cytokines upon LPS stimulation. In conclusion, our data indicate an in vivo activation of circulating monocytes during sepsis as well as in noninfectious shock and suggest that complex regulatory mechanisms can downregulate the production of cytokines by monocytes during severe infections.

Adult↗
PubMed1991

Heat and moisture exchanger vs heated humidifier during long-term mechanical ventilation. A prospective randomized study.

Adequate humidification of inspired gases with HMEs during long-term MV remains controversial. In this study, a comparison is made between tracheal secretions during long-term MV either with HME or conventional HH. Both the HME and HH groups were similar with respect to age, sex, diagnosis, duration of MV, SAPS and mortality. Temperature of gases in the tracheal tube was lower and the amount of tracheal instillations was greater in the HME group than in the HH group. Tracheal secretions became thicker between day 1 (control) and day 5, in the HME group than in the HH group. Four and two tube occlusions occurred in HME and HH groups, respectively. Tracheal bacterial colonization was similar in the two groups. Given the advantages of HME (reduced nurses' work and financial cost), HME could be routinely used under cautious surveillance and replaced by HH if difficulty in suctioning occurs.

Female↗
PubMed1990

Acute myocardiotoxicity during 5-fluorouracil therapy.

A 38-year-old man with a colonic carcinoma experienced cardiogenic shock during continuous intravenous treatment with 5-fluorouracil (5-FU), without clinical or electrical signs of coronary insufficiency and with a normal coronary angiogram. His symptoms resolved after eight days of inotropic and vasodilator therapy. Because of the severity of the shock, rechallenge was not performed. This is the first case of acute cardiac failure without coronary ischemia, associated with 5-FU monotherapy. Experimental studies suggest that this adverse effect could be due to myocardial accumulation of 5-FU leading to depletion of high energy phosphate compounds. This might also explain the more frequently seen acute coronary insufficiency due to 5-FU.

Adult↗