Thrombocytopenia has a bimodal PC-dependent effect on the occurrence of distal organ injury during Klebsiella-induced pneumosepsis. Very low-PC, low-PC, and control mice were infected with K pneumoniae via the airways and euthanized at 12 or 44 hours. AST (A) and ALT (B) were measured in plasma as markers for hepatocellular injury. (C) LDH was measured in plasma as a more general cell injury marker. (D) Systemic neutrophil activation was assessed by measuring MPO in plasma. Data are expressed as box-and-whisker plots depicting the smallest observation, lower quartile, median, upper quartile, and largest observation, or as bars depicting mean ± SEM. n = 8 mice per group. *P < .05 and **P < .005 vs control; #P < .05 and ##P < .005 vs low-PC.