Background: Allograft infection after lung transplantation (OLT) has a significant impact on outcomes and represents a diagnostic challenge. Pneumocystis jirovecii causes an opportunistic infection, life-threatening pneumonia among immunocompromised patients. Airway colonization with Pseudomonas aeruginosa is common in lung transplant recipients. The aim of the study was to evaluate procalcitonin (PCT) serum concentrations during P jiroveci and P aeruginosa colonization/infections in lung transplant recipients.
Materials and methods: Fifteen OLT patients were retrospectively enrolled into the study (10 men and 5 women) of overall mean age of 41.4 +/- 14.6 years. In seven patients, P jiroveci cysts were diagnosed (group J) and in 13 patients, we isolated P aeruginosa (group A). In respiratory samples, P jiroveci was detected using an indirect immunofluorescence method, and P aeruginosa was isolated using routine microbiologic methods. PCT was measured using immunoluminescence assay.
Results: The average PCT value in group A was 0.30 +/- 0.21 and in group J, 0.88 +/- 0.43, a difference that was not significant. In group A, 3 patients (23.1%) has PCT values indicating moderate infection risk (PCT > 0.5) and one patient (7.7%), a high infection risk (PCT > 2.0 and <10). In group J, three patients (42.9%) has PCT values indicating moderate and one patient (14.3%), high infection risk.
Conclusions: Bronchial tree colonization with P jiroveci as well as P aeruginosa colonization can be associated with increased PCT suggesting a general, systemic response in addition to local colonization.