H. Georges

Diagnostic and prognostic values of admission procalcitonin levels in community-acquired pneumonia in an intensive care unit.

AbstractBackground:Measurement of procalcitonin (PCT) has been studied for several years in infectious diseases. Some studies have focused on community–acquired pneumonia (CAP) but only one was conducted in critically ill patients hospitalized in an intensive care unit (ICU).Patients and Methods:To determine the diagnostic and prognostic role of PCT in patients admitted in an intensive care unit for severe CAP, 110 patients hospitalized in our unit were prospectively studied. Within 48 hours following ICU admission, PCT serum level was measured with a quantitative method above a threshold value of 0.5 ng/ml.Results:Initially focusing on the diagnostic value of PCT, 20% of the patients had a serum PCT level < 0.5 ng/ml, 30% between 0.5 ng/ml and 2 ng/ml, and 50% ≥ 2 ng/ml. Serum PCT level was higher in microbiologically documented CAP (median = 4.9 ng/ml vs 1.5 ng/ml if no bacteria were found; p = 0.001), but was not predictive of any specific bacterial agent. Concerning the prognostic value, the serum PCT level was higher for bacteremic patients and/or septic shock patients (4.9 ng/ml vs 1.5 ng/ml; p = 0.0003). Moreover, PCT levels were increased in patients who developed, during their ICU stay, infection–related complications (septic shock, multiorgan dysfunction, acute respiratory distress syndrome and disseminated intravascular coagulation). Finally, the initial PCT level was significantly higher in patients who died during the ICU stay (5.6 ng/ml vs 1.5 ng/ml; p < 0.0001). Such a relationship was not found with C–reactive protein (CRP).Conclusion:In ICU patients admitted for severe CAP, initial PCT values could be an interesting predictor for complications and mortality.

Pulmonary disposition of vancomycin in critically ill patients

Vancomycin penetration in epithelium lining fluid was studied in ten mechanically ventilated patients with methicillin-resistantStaphylococcus aureus pneumonia 24 hours after the onset of treatment. Vancomycin was given intravenously at a daily dose of 30 mg/kg. Vancomycin levels were detectable in four patients (range, 1–2.77 μg/ml). Concordance between high plasma concentrations (> 20 μg/ml) and detectable vancomycin levels in epithelium lining fluid was noted. These results suggest that the pulmonary disposition of vancomycin remains low for most patients 24 h after the onset of treatment compared with the minimum inhibitory concentrations for most gram-positive organisms. One therapeutic goal of vancomycin treatment could be to obtain through plasma levels of 20 μg/ml. Further studies are required to determine the clinical relevance of these observations.

Hospital-acquired pneumonia in critically ill patients: factors associated with episodes due to imipenem-resistant organisms.

Background:Inadequate initial antimicrobial therapy represents one of the factors associated with mortality of patients suffering from hospital-acquired pneumonia. According to its wide antimicrobial spectrum, imipenem belongs to the usual antibiotics proposed by current guidelines for such a therapy. However, major changes in the antibiotic susceptibility patterns of bacteria in the intensive care unit (ICU) have occurred. Our goal was to determine the incidence of hospital-acquired pneumonia (HAP) due to imipenem-resistant organism(s) in our ICU and to identify factors associated with such a resistance.Patients and Methods:From January 1994 to December 2001, all consecutive patients admitted to our ICU for HAP or exhibiting HAP during their ICU stay were included in an observational cohort. Patients with a bacteriologically documented HAP were studied. For each causative pathogen, imipenem susceptibility was routinely determined. Patients with an HAP episode due to at least one imipenem-resistant causative organism were compared with patients who developed HAP in which all incriminated pathogens were imipenem susceptible.Results:235 patients were included in our observational cohort. Among them, 168 had an HAP episode with a bacteriologically proven infection. In 42 patients (25%), at least one causative organism was resistant to imipenem. The 44 imipenem-resistant organisms were Staphylococcus aureus (n = 15), Pseudomonas aeruginosa (n = 14), Stenotrophomonas maltophilia (n = 13), and Acinetobacter baumannii (n = 2). Multivariate analysis identified four significant independent factors associated with resistance of causative organism(s) to imipenem: prior use of a fluoroquinolone (AOR = 3.9; 95% CI: 1.8 to 8.8; p < 0.0001), prior use of an aminoglycoside (AOR = 2.6; CI: 1.2 to 5.9; p = 0.02), use of invasive blood pressure monitoring (AOR = 2.7; CI: 1.0 to 7.0; p = 0.04) and bilateral chest X-ray involvement (AOR = 2.6; CI: 1.1 to 5.8; p = 0.02).Conclusion:Factors associated with potential inadequacy of imipenem used as the single antibiotic for initial empiric treatment for HAP were identified. When they are present, imipenem should be either combined with antibiotics such as vancomycin and ciprofloxacin or replaced with another broad-spectrum antimicrobial regimen.

Adult community-acquired bacterial meningitis requiring ICU admission: epidemiological data, prognosis factors and adherence to IDSA guidelines

Numerous guidelines are available to guide empirical antimicrobial therapy (EAT) in acute bacterial meningitis (ABM) patients. We analysed prognosis factors and compliance to the Infectious Diseases Society of America (IDSA) guidelines in ABM patients requiring stay in an intensive care unit (ICU). A 10-year retrospective study, using prospectively collected data, in 82 ABM patients admitted to a 16-bed university-affiliated French ICU was undertaken. Seventeen patients (20.7%) died during ICU stay. Multivariate analysis isolated four factors associated with in-ICU death: alcoholism (P = 0.007), acute kidney injury (P = 0.006), age >60 years (P = 0.006) and ICU admission for neurological failure (P = 0.01). Causative pathogens were isolated for 62 (75.6%) patients, including 29 pneumococci, 14/28 of which were non-susceptible to penicillin. No characteristics, particularly recent hospitalisation and/or antibiotic delivery, was associated with penicillin susceptibility. Compliance to IDSA guidelines was 65%. Non-compliance concerned to be essentially the non-delivery or low dosage of vancomycin. Treatment compatible with IDSA guidelines was associated with a decreased ICU mortality in univariate (61.5% survival vs. 35.3%, P = 0.05) but not in multivariate analysis. In-ICU mortality associated with ABM remains high. Prognosis factors are related to the severity of disease or underlying conditions. Penicillin non-susceptible Streptococcus pneumoniae can occur without any of the usual predisposing factors.

Impact of combination therapy with aminoglycosides on the outcome of ICU-acquired bacteraemias

Pharmacodynamic studies report on the rapid bactericidal activity of aminoglycosides, conferring them as being of theoretical interest for bacteraemia treatment. We assessed this issue in a retrospective study of patients with intensive care unit (ICU)-acquired bacteraemias. To determine the impact of aminoglycosides in antimicrobial combination on the outcome of patients with bacteraemia, we performed a monovariate analysis and a logistic regression analysis comparing patients treated with or without aminoglycosides. Forty-eight bacteraemias in 48 patients were included. Eighteen patients received aminoglycosides. Baseline characteristics as well as adaptation and adequation of antibiotherapy did not differ in patients who did or did not receive aminoglycosides. Patients who received aminoglycosides had longer time alive away from the ICU (11.3 ± 8.9 (10 [0–20]) vs. 3.2 ± 6.6 (0 [0–2] days; p = 0.002) and free from mechanical ventilation (12.5 ± 9.3 (14 [0–21] vs. 5.5 ± 9.2 (0 [0–10] days; p = 0.02) on day 28. The ICU mortality was 16% in the aminoglycoside group versus 46% (p = 0.03). In the multivariate analysis, patients treated with aminoglycosides were 6 times less likely to die than those treated without aminoglycosides (confidence interval [CI] = [1.3–28.9]; p = 0.02). Our study supports the hypothesis that combination short-term antibiotherapy with an aminoglycoside for ICU-acquired bacteraemias could increase survival.

Survival in critically ill patients with acute kidney injury treated with early hemodiafiltration.

PURPOSE Early renal replacement therapy (RRT) initiation should theoretically influence many physiological disorders related to acute kidney injury (AKI). Currently, there is no consensus about RRT timing in intensive care unit (ICU) patients. METHODS We performed a retrospective analysis of all critically ill patients who received RRT in our ICU during a 3 year-period. Our goal was to identify mortality risk factors and if RRT initiation timing had an impact on survival. RRT timing was calculated from the moment the patient was classified as having acute kidney injury in the RIFLE classification. RESULTS A hundred and ten patients received RRT. We identified four independent mortality risk factors: need for mechanical ventilation (OR = 12.82 (1.305 - 125.868, p = 0.0286); RRT initiation timing >16 h (OR = 5.66 (1.954 - 16.351), p = 0.0014); urine output on admission <500 ml/day (OR = 4.52 (1.666 - 12.251), p = 0.003); and SAPS II on admission >70 (OR = 3.45 (1.216 - 9.815), p = 0.02). The RRT initiation =16 h and RRT initiation >16 h groups presented the same baseline characteristics, except for more severe gravity scores and kidney failure in the early RRT group. CONCLUSIONS Early RRT in ICU patients with acute kidney injury or failure was associated with increased survival.

Exchange transfusion for severe malaria.

AbstractBackground: Exchange transfusion (ET) is a controversial ancillary treatment of severe falciparum malaria. Patients and Methods: We conducted a retrospective analysis of severe malaria treated in our institution. Nine cases of ET were identified between 1991 and 1998 and compared to 12 controls with similar parasitemia. Results: Groups were similar at admission except for an increased age in the ET group (p < 0.02). All patients received iv quinine. Outcome was similar in both groups (two deaths in the ET group, three in the control group). However, in patients with parasitemia > 30%, the death rate was significantly lower in ET patients than in controls (0/4 vs 3/3, p < 0.029). Conclusion: Despite definitive data from controlled trials, we suggest that ET should be considered in severe malaria cases with very high parasitemia and severity criteria or worsening clinical condition despite adequate chemotherapy.

Syndrome respiratoire aigu sévère

Résumé Le syndrome respiratoire aigu sévère (severe acute respiratory syndrome, SARS) est apparu à l’automne 2002 dans la province de Guangdong en Chine. L’épidémie s’est rapidement propagée à travers le monde pour toucher, courant avril, plus de 26 pays avec un total de cas à cette même date proche de 3500 cas. La symptomatologie associe des formes modérées se manifestant par une fièvre, une hypoxie, avec des formes de gravité majeure responsables de syndrome de détresse aigue nécessitant l’hospitalisation en unité de réanimation. Des formes digestives ont aussi récemment été décrites. Cette épidémie a suscité une réponse extrêmement rapide de la communauté internationale qui en quelques semaines a permis d’isoler l’agent responsable, un nouveau Coronavirus, de proposer une prise en charge thérapeutique et des mesures spécifiques pour limiter la diffusion de l’épidémie. Cette revue rassemble l’ensemble des données actuellement disponibles sur le SARS, de l’histoire de l’épidémie aux propositions thérapeutiques disponibles en date d’avril 2003. Abstract In the Fall of 2002 a report from Guangdong Province in China showed the occurrence of an outbreak of atypical pneumonia. This outbreak rapidly progressed from China to Hong Kong, Singapore, Toronto, and the USA, to more than 25 countries worldwide and almost 3500 cases to date in april 2003. The clinical features associate a fever with mild respiratory symptoms which can progress to a typical acute respiratory distress syndrome requiring intensive care unit admission. Enteric forms with diarrhea were recently described in Hong Kong. The medical community responded very rapidly and united in front of this major health crisis. In a couple weeks, the agent, a new Coronavirus was isolated, therapeutic guidelines were proposed and measures to limit the outbreak diffusion were started worldwide. We summarize here the history of the outbreak, the clinical, laboratory and radiological features of SARS. April 2003 therapeutic guidelines are also reported.