Blood clearance and organ localization of Candida albicans and E coli following dual infection in rats.

Immunosuppressed prematures, cancer patients, and transplant recipients are susceptible to bacterial or fungal sepsis or both. This report evaluates whether the ability of the reticuloendothelial system (RES) to remove blood-borne viable radiolabeled 35S Escherichia coli and 3H-Leucine Candida albicans is adversely affected by a dual intravenous challenge of these organisms. Male Sprague Dawley rats (n = 150) weighing 175 to 180 g were placed in 5 experimental groups (n = 30). Group I received intravenous (IV) C albicans (10(7)/mL), group II received E coli (10(9)/mL), group III received a dual injection of C albicans and E coli, group IV received Candida 1 hour prior to E coli, and group V received E coli 1 hour prior to fungi. At 1, 4, and 24 hours, tissue samples (50 to 100 mg) of liver, spleen, kidneys, and lungs were processed for liquid scintillation counting. Organ distribution of bacteria and fungi was calculated and expressed as mean percent +/- SD of labeled organisms. The liver trapped 72% +/- 10% and the lungs 1.1% +/- 0.3% of E coli (group II) (P < .001). The organ distribution of Candida (group I), however, was similar in liver and lungs (42.5% +/- 10% and 41.4% +/- 6.4%, respectively). Liver localization of E coli was unaffected by simultaneous or staggered fungal injection (groups III, 4, and V). Lung distribution of E coli following dual injection (group III) was significantly higher than controls (group II) (3.6% +/- 0.7% v 1.1% +/- 0.3%; P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)