Tilo Freiwald1,2,3, Stefan Büttner1, Nardos T Cheru2, Despina Avaniadi1, Simon S Martin4, Christoph Stephan5, Rainer U Pliquett6, Aida Asbe-Vollkopf1, Gundolf Schüttfort5, Volkmar Jacobi4, Eva Herrmann7, Helmut Geiger1, Ingeborg A Hauser1. 1. Medical Clinic III, Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt, Germany. 2. Immunoregulation Section, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA. 3. Complement and Inflammation Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA. 4. Department of Radiology, University Hospital Frankfurt, Goethe-University, Frankfurt, Germany. 5. Department of Infectious Diseases, University Hospital Frankfurt, Goethe-University, Frankfurt, Germany. 6. Department of Nephrology and Diabetology, Carl-Thiem Hospital Cottbus, Cottbus, Germany. 7. Institute for Biostatistics and Mathematical Modeling, Goethe-University, Frankfurt, Germany.
Abstract
BACKGROUND: Pneumocystis jirovecii pneumonia (PcP) remains a life-threatening opportunistic infection after solid organ transplantation, even in the era of Pneumocystis prophylaxis. The association between risk of developing PcP and low CD4+ T cell counts has been well established. However, it is unknown whether lymphopenia in the context of post-renal transplant PcP increases the risk of mortality. METHODS: We carried out a retrospective analysis of a cohort of kidney transplant patients with PcP (n = 49) to determine the risk factors for mortality associated with PcP. We correlated clinical and demographic data with the outcome of the disease. For CD4+ T cell counts, we used the Wilcoxon rank sum test for in-hospital mortality and a Cox proportional-hazards regression model for 60-day mortality. RESULTS: In univariate analyses, high CRP, high neutrophils, CD4+ T cell lymphopenia, mechanical ventilation, and high acute kidney injury network stage were associated with in-hospital mortality following presentation with PcP. In a receiver-operator characteristic (ROC) analysis, an optimum cutoff of ≤200 CD4+ T cells/µL predicted in-hospital mortality, CD4+ T cell lymphopenia remained a risk factor in a Cox regression model. CONCLUSIONS: Low CD4+ T cell count in kidney transplant recipients is a biomarker for disease severity and a risk factor for in-hospital mortality following presentation with PcP.
BACKGROUND:Pneumocystis jirovecii pneumonia (PcP) remains a life-threatening opportunistic infection after solid organ transplantation, even in the era of Pneumocystis prophylaxis. The association between risk of developing PcP and low CD4+ T cell counts has been well established. However, it is unknown whether lymphopenia in the context of post-renal transplant PcP increases the risk of mortality. METHODS: We carried out a retrospective analysis of a cohort of kidney transplant patients with PcP (n = 49) to determine the risk factors for mortality associated with PcP. We correlated clinical and demographic data with the outcome of the disease. For CD4+ T cell counts, we used the Wilcoxon rank sum test for in-hospital mortality and a Cox proportional-hazards regression model for 60-day mortality. RESULTS: In univariate analyses, high CRP, high neutrophils, CD4+ T cell lymphopenia, mechanical ventilation, and high acute kidney injury network stage were associated with in-hospital mortality following presentation with PcP. In a receiver-operator characteristic (ROC) analysis, an optimum cutoff of ≤200 CD4+ T cells/µL predicted in-hospital mortality, CD4+ T cell lymphopenia remained a risk factor in a Cox regression model. CONCLUSIONS: Low CD4+ T cell count in kidney transplant recipients is a biomarker for disease severity and a risk factor for in-hospital mortality following presentation with PcP.