Leflunomide therapy for BK virus allograft nephropathy after pediatric kidney transplantation.

The BK virus (BKV) can be reactivated with immunosuppressive treatment in renal allograft recipients, which can result in interstitial nephritis (BKV-associated nephropathy, BKVAN) and lead to renal allograft failure. Recently, leflunomide has been reported in some case series of BKVAN with favorable results. Most studies have included only adult patients, we herein report a pediatric case and include a literature review. The patient was a nine-yr-old female with end-stage renal disease due to hypoxic kidney injury. A deceased donor renal transplant was performed and good initial allograft function was achieved following treatment with prednisolone, tacrolimus and mycophenolate mofetil. The serum Cr level increased to 1.6 mg/dL over the following four-month period. A kidney biopsy revealed pathologic findings of acute cellular rejection and BK nephropathy. After methylprednisolone pulse therapy was administered to control acute rejection, the tacrolimus dose was reduced, and intravenous immunoglobulin treatment and leflunomide therapy were administered to control the BKVAN. Over the following 18 months, the viral load steadily decreased and remained below 100 copies/mL in the plasma. Leflunomide therapy in addition to a reduction of the immunosuppressive therapies resulted in a significant decline in the BK viral load without further deterioration of renal function.

Correlation between myocardial perfusion abnormalities detected with intermittent imaging using intravenous perfluorocarbon microbubbles and radioisotope imaging during high-dose dipyridamole stress echo.

BACKGROUND: The clinical accuracy of myocardial contrast echocardiography (MCE) using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles during dipyridamole stress has not been evaluated in a multicenter setting. HYPOTHESIS: The accuracy of dipyridamole stress contrast echo in the detection of coronary artery disease (CAD) using myocardial perfusion images is high in comparison with technetium-99 (99Tc) sestamibi single-photon emission computed tomography (MIBI SPECT) and increases the accuracy of wall motion data. METHODS: In 68 consecutive nonselected patients (46 men; mean age 66 years) from three different institutions in two countries. dipyridamole stress echo and SPECT with 99mTc MIBI were compared. Continuous intravenous (IV) infusion of perfluorocarbon exposed sonicated dextrose albumin (PESDA) (2-5 cc/min) was administered for baseline myocardial perfusion using triggered harmonic end systolic frames. Real-time digitized images were used for wall motion analysis. Dipyridamole was then injected in two steps: (1) 0.56 mg/kg for 3 min, (2) 0.28 mg/kg for 1 min, if the first step was negative for an inducible wall motion abnormality. After dipyridamole injection, myocardial contrast enhancement and wall motion were analyzed again by the same methodology. RESULTS: There were 35 patients with perfusion defects by SPECT. Wall motion was abnormal in 22, while MCE was abnormal in 32. Wall motion and MCE each had one false positive. The proportion of correctly assigned patients was significantly better with MCE than with wall motion (p = 0.03; chi square test). CONCLUSIONS: Myocardial contrast echocardiography, using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles, is a very effective method for detecting coronary artery disease during dipyridamole stress echo.