Safety and diagnostic yield of transjugular renal biopsy.

PURPOSE: To evaluate the safety and tissue acquisition with transjugular renal biopsy (TJRB) by using the Quick-Core method in patients who were at high risk for complications with percutaneous renal biopsy. MATERIALS AND METHODS: This was a retrospective study, and indication for the transjugular route, complications, clinical and laboratory data, and adequacy of samples were abstracted from patient records. TJRB was performed when the patient had thrombocytopenia or coagulopathy and was at high risk for bleeding from percutaneous renal biopsy. Follow-up images were available in 25 patients; nine underwent abdominal ultrasonography (US) and 17 underwent computed tomography (CT) (one patient underwent both US and CT). The hemoglobin level, prothrombin time, international normalized ratio (INR), partial thromboplastin time, platelet count, and serum creatinine level were obtained before and after biopsy, and these findings were correlated with clinical outcomes. RESULTS: Thirty-nine patients underwent 39 TJRB procedures and comprise the current study population. The procedure was technically successful in 38 of the 39 patients (97%). Twenty-four of 39 patients (63%) had a platelet count of less than or equal to 75 x 10(9)/L, 11 (29%) had an elevated INR of more than 1.4, and seven received therapeutic anticoagulation. Patients with a platelet count of less than or equal to 75 x 10(9)/L or those with an elevated INR of more than 1.4 after transfusion were not at increased risk of hematoma formation (P = not statistically significant). The mean serum creatinine level at biopsy was 283 mumol/L +/- 150. A mean of 1.8 cores +/- 1.1 were obtained, with 5.0 glomeruli +/- 3.8, 2.1 glomeruli +/- 2.8, and 2.4 glomeruli +/- 3 at light, immunofluorescence, and electron microscopy, respectively. The renal tissue was sufficient for diagnosis in 92% of patients. Major complications occurred in one patient (2.6%). Minor complications-primarily renal hematoma-occurred in 52% of the patients. Contrast medium-induced nephropathy occurred in three patients (7.8%), two of whom also had renal hematomas. CONCLUSIONS: TJRB is a relatively safe and effective diagnostic tool in high-risk patients with coagulopathy and thrombocytopenia who require renal tissue for accurate diagnosis.

Influence of surveillance renal allograft biopsy on diagnosis and prognosis of polyomavirus-associated nephropathy.

BACKGROUND: Polyomavirus-associated nephropathy (PVAN) is an increasingly prevalent cause of allograft dysfunction. METHODS: In 18 histologically proven cases of PVAN managed by reduced immunosuppression, monitoring of serum creatinine, and repeated biopsy, graft outcomes were correlated with clinical and histologic indices. Six months postdiagnosis the status of each graft was classified as poor (N = 7) or satisfactory (N = 11). Poor transplant status was defined as graft loss, increased severity of PVAN on repeat biopsy, or serum creatinine>3.0 mg/dL. Diagnosis resulted from either surveillance allograft biopsies (N = 8) or biopsies performed for increased serum creatinine (nonsurveillance, N = 10). RESULTS: The surveillance biopsy group was more likely than the nonsurveillance group to have satisfactory graft status at 6 months (eight of eight vs. three of ten, P = 0.004) and had significantly lower serum creatinine at diagnosis, 3, and 6 months. Histologic scoring for chronic interstitial and tubular injury was lower in diagnostic surveillance biopsies compared to nonsurveillance biopsies (P = 0.01). Satisfactory transplant status was also associated with reduced or absent virus on repeat biopsy (P = 0.01). Poor transplant status was associated with a higher frequency of recipientneg/donorpos cytomegalovirus (CMV) serology (71% vs. 9%, P = 0.01). CONCLUSION: Surveillance allograft biopsy provides an important means for earlier detection of PVAN and permits timely alterations to immunosuppression. Early diagnosis is associated with a lesser degree of interstitial fibrosis at diagnosis and lower baseline and subsequent serum creatinine.