Usefulness of beta-D glucan in diagnosing Pneumocystis carinii pneumonia and monitoring its treatment in a living-donor liver-transplant recipient

Pneumocystis carinii pneumonia (PCP) is one of the fatal complications encountered after liver transplantation. The diagnosis of PCP is sometimes very difficult, because detection of the bacteria itself is not easy under some conditions, and the serum level of the chemical mediator is not yet considered to be a definitive diagnostic marker. We report a case of PCP that occurred 3 months after transplantation in a living-donor liver-transplant recipient; the disease developed during the course of outpatient follow-up when the patient's condition was stable. The patient was maintained with the usual level of immunosuppressants, using tacrolimus, steroid, and mycophenolate mofetil. The patient had a dry cough with mild fever, and a chest computed tomography (CT) scan showed a reticular shadow in the left lung field. The plasma level of beta-D glucan was high (135pg/ml). We suspected an invasive fungal infection, but no pathogen was detected by routine fungal culture and cytology. Finally, P. carinii was detected by polymerase chain reaction (PCR), and we started treatment with trimethoprim-sulfamethoxazole (TMP/SMX) combined with an antifungal agent. During this period, the level of beta-D glucan correlated with the patient's clinical symptoms; this marker was very useful for monitoring the treatment of PCP in this living-donor liver-transplant recipient.