Electronic Supplementary Material s4

ELECTRONIC SUPPLEMENTARY MATERIAL

Impact of antifungal treatment on Candida-Pseudomonas interaction: a

preliminary retrospective case-control study

Saad NSEIR1,2, MD, Elsa JOZEFOWICZ1, MD, Béatrice CAVESTRI1, MD, Boualem

SENDID3, MD, Christophe Di POMPEO2, PhD, MD, Florent DEWAVRIN1, MD, Raphaël

FAVORY1, MD, Micheline ROUSSEL-DELVALLEZ4, MD, and Alain DUROCHER1,2, MD.

1Intensive Care Unit, 3Mycology Laboratory, 4Bacteriology Laboratory; Calmette Hospital,

University Hospital of Lille, boulevard du Pr Leclercq, 59037 Lille cedex, France.

2Medical Assessment Laboratory, EA 3614, Lille II University, 1 place de Verdun, 59045

Lille, France. PATIENTS AND METHODS

Definitions

Chronic respiratory disease was defined as chronic obstructive pulmonary disease

(COPD) [E1] and/or chronic restrictive respiratory failure. Immunosuppression was defined as active solid or hematology malignancy, and chronic immunosuppressive treatment. During the study period, no HIV patient or neutropenic patient were admitted to the ICU. Prior antibiotic treatment was defined as any antibiotic treatment during the two weeks preceding

ICU admission.

Statistical analysis

SPSS software (SPSS, Chicago, IL) was used for data analysis. Results are presented as frequency (%) for qualitative variables or mean  SD for quantitative variables. Qualitative variables were compared using 2 test or Fisher’s exact test where appropriate. Mann-

Whitney U-test was used to compare quantitative variables. Odd ratios were calculated for all significant (p <0.05) qualitative variables in univariate analysis, and for all significant variables in multivariate analysis.

To determine variables associated with P. aeruginosa VAP or tracheobronchial colonization, cases were compared with controls by univariate and multivariate analyses. The following variables were included in the univariate analysis: age, gender, simplified acute physiology score II and logistic organ dysfunction on ICU admission, chronic diseases, cause for ICU admission, number of candida-colonized sites, antifungal and antibiotic treatment, duration of mechanical ventilation. Only variables with p value < 0.2 in univariate analysis were included in the stepwise logistic regression model. In patients with P. aeruginosa VAP or tracheobronchial colonization, only exposure to potential risk factors before first positive respiratory specimen for P. aeruginosa was taken into account.

2 In order to determine risk factors for VAP related to P. aeruginosa, additional subgroup analysis was performed. Cases with VAP were compared with their controls using univariate and multivariate analyses. Only variables with p value < 0.2 in univariate analysis were included in the stepwise logistic regression model.

RESULTS

During the study period, 407 patients were intubated and ventilated > 48h during their

ICU stay. 5 (2%) patients were excluded because of absence of screening for P. aeruginosa and Candida spp at ICU admission. Among the 402 remaining patients, 117 (29%) patients developed a Candida spp tracheobronchial colonization and were eligible. 15 patients were excluded for P. aeruginosa VAP or tracheobronchial colonization diagnosed before or at the same time than Candida spp tracheobronchial colonization.

Mycology results and antifungal treatment

The most frequently isolated Candida were: C. albicans (67%), C. glabrata (9%), C. tropicalis (6%), and others (16%). 21 (20%) patients were colonized with > 1 Candida spp.

The most frequently used antifungals were: fluconazole (66%), voriconazole (22%), caspofungin (16%), and liposomal amphotericin B (5 %). 4 patients received more than one antifungal agent.

Number of patients with C. albicans was significantly higher in patients who did not receive antifungal treatment than in treated patients (61 of 66 [92%] patients vs 26 of 36

[72%], p = 0.019). However number of patients with C. albicans was similar in case and control patients (15 of 19 patients [78%] vs 30 of 38 [78%], p = 0.642). All C. albicans were susceptible to fluconazole. Mean time between Candida spp tracheobronchial colonization and starting antifungal treatment was 10 ± 8d.

3 Characteristics of all study patients

Duration of treatment with antipseudomonal antibiotics (6 ± 11 vs 5 ± 7d, p = 0.694), and duration of treatment with non-antipseudomonal third-generation cephalosporins (3 ± 6 vs 3 ± 6d, p = 0.914) were similar in patients treated with antifungals as compared with untreated patients.

Characteristics and outcomes of case and control patients

Duration of treatment with antipseudomonal antibiotics (4 ± 7 vs 7 ± 11 d, p = 0.331), and duration of treatment with non-antipseudomonal third-generation cephalosporins (4 ± 6 vs

3 ± 6d, p = 0.209) were similar in case and control patients.

VAP was polymicrobial in 2 of the 10 cases with P. aeruginosa VAP. C. albicans was isolated in 6 of the 10 patients with P. aeruginosa VAP.

Duration of mechanical ventilation (40 ± 33 vs 22 ± 15), and ICU stay (48 ± 33 vs 26

± 22) were significantly (p < 0.001) longer in case than in control patients. ICU-mortality rate was similar in case and control patients (36% vs 44%, p = 0.3).

Risk factors for P. aeruginosa VAP

Risk factors for P. aeruginosa VAP by univariate analysis are presented in Table E1.

Only hospital acquired pneumonia at ICU admission was identified as an independent risk factor for P. aeruginosa VAP (OR [95% CI] = 20 [1-315], p = 0.003).

REFERENCES:

E1. Standards for the diagnosis and care of patients with chronic obstructive pulmonary disease. American Thoracic Society (1995) Am J Respir Crit Care Med 152:S77-121

4 Table E1. Risk factors for ventilator-associated pneumonia related to P. aeruginosa by univariate analysis.

Cases with VAP Controls P

(n = 10) (n = 20) At ICU admission Age, years 63 ± 12 57 ± 18 .231 Male gender 8 (80) 13 (65) .344 SAPS II 53 ± 20 49 ± 19 .588 LOD 8 ± 4 7 ± 5 .502 Surgery 1 (10) 2 (10) .749 Diabetes mellitus 3 (30) 5 (25) .548 Prior antibiotic treatment 3 (30) 9 (45) .350 Immunosuppression 1 (10) 2 (10) .749 Chronic respiratory disease 1 (10) 3 (15) .593 Chronic heart failure 3 (30) 4 (20) .429 Cirrhosis 1 (10) 2 (10) .749 Chronic renal failure 1 (10) 1 (5) .563 Cause for ICU admission ARDS 0 (0) 2 (10) .437 Pneumonia 5 (5) 7 (35) .344 CAP 1 (1) 6 (30) .228 HAP 4 (40) 1 (5) .031* Acute exacerbation of COPD 0 (0) 4 (20) .177 Acute poisoning 2 (20) 1 (5) .251 Septic shock 2 (20) 2 (10) .407 Congestive heart failure 1 (1) 1 (5) .563 Others 0 (0) 3 (15) .102 During ICU stay Number of Candida-colonized sites 1.5 ± 0.6 1.9 ± 1.5 .983 Antifungal treatment 2 (20) 9 (45) .175 Duration of antifungal treatment, d 11 ± 14 18 ± 16 .169 Antibiotic treatment 9 (90) 19 (95) .563 -antipseudomonal antibiotics 3 (30) 8 (40) .452 -non-antipseudomonal 3GC 3 (30) 4 (20) .429 -other antibiotics 9 (90) 17 (85) .593 Duration of antibiotic treatment, d 26 ± 17 20 ± 17 .214 Duration of mechanical ventilation, d 17 ± 8 24 ± 16 .502 Data are No. (%) or mean ± SD. *OR (95% CI) = 12 (1-136).

SAPS simplified acute physiology score, LOD logistic organ dysfunction, ARDS acute respiratory distress syndrome, CAP community-acquired pneumonia, HAP hospital-acquired pneumonia, 3GC third generation cephalosporins.

5 In patients with VAP, only exposure to potential risk factors before first P. aeruginosa VAP episode was taken into account.