[Sequential monitoring of renal transplant with aspiration cytology]. / Monitorização seqüencial do transplante renal com citologia aspirativa.

OBJECTIVE: To evaluate the utility of kidney aspiration cytology in the sequential monitorization of acute rejection in renal transplant patients. PATIENTS AND METHODS: Thirty patients were submitted to 376 aspirations. The clinical diagnoses were independently established. RESULTS: The representativity of the samples reached 82.7%. The total corrected increment index and the number of immunoactivated cells were higher during acute rejection as compared to normal allograft function, acute tubular necrosis, and cyclosporine nephrotoxicity. The parameters to the diagnosis of acute rejection were sensitivity: 71.8%, specificity: 87.3%, positive predictive value: 50.9%, negative predictive value: 94.9% and accuracy 84.9%. The false positive results were mainly related to cytomegalovirus infection or to the administration of OKT3. In 10 out of 11 false negative results incipient immunoactivation was present alerting to the possibility of acute rejection. CONCLUSIONS: Kidney aspiration cytology is a useful tool for the sequential monitorization of acute rejection in renal transplant patients. The best results are reached when the results of aspiration cytology are analyzed with the clinical data.

Nephrotoxicity of acyclovir and ganciclovir in rats: evaluation of glomerular hemodynamics.

Whole-kidney function and glomerular hemodynamics were evaluated after acute (50 mg/kg, iv, in bolus) and short-term chronic (50 mg mg/kg, ip, 5 days) acyclovir (ACV) and short-term chronic ganciclovir (Gan; 30 mg/kg, ip, 5 days) treatment in envolemic Munich-Wistar rats. The evaluation of whole-kidney function of the ACV groups showed a significant reduction in total GFR (0.96 +/- 0.10 to 0.28 +/- 0.02 mL/min in the acute group, P < 0.05, and 1.04 +/- 0.09 to 0.33 +/- 0.04 mL/min in the chronic group, P < 0.05) with a marked increase in total renal vascular resistance (TRVR) (33 +/- 5 to 122 +/- 26 mm Hg.min/mL in the acute group and 28 +/- 3 to 74 +/- 18 mm Hg.min/mL in the chronic group, P < 0.05) and a reduction in RPF (2.29 +/- 0.25 to 0.81 +/- 0.15 mL/min in the acute group and 2.57 +/- 0.36 to 1.30 +/- 0.40 mL/min in the chronic group, P < 0.05). Conversely, urinary flow (V') was unchanged (3.6 +/- 0.4 to 3.6 +/- 0.2 microL/min in the acute group) or elevated (3.7 +/- 0.6 to 6.6 +/- 1.4 microL/min in the chronic group, P < 0.05). The evaluation of glomerular hemodynamics after ACV treatment showed a reduction in single-nephron GFR (SNGFR) (46.4 +/- 5.3 to 26.2 +/- 3.4 nL/min in the acute group and 38.7 +/- 5.7 to 21.1 +/- 5.7 nL/min in the chronic group, P < 0.05), a significant elevation in total arteriolar resistance (RT) (2.90 +/- 0.44 to 4.94 +/- 0.77 x 10(10) dyn.s.cm-5 in the acute group and 3.72 +/- 0.45 to 9.00 +/- 2.40 x 10(10) dyn.s.cm-5 in the chronic group, P < 0.05) and a severe reduction in glomerular plasma flow rate (QA) (152.6 +/- 29.5 to 103.8 +/- 27.8 nL/min in the acute group and 149.1 +/- 29.8 to 68.5 +/- 10.0 nL/min in the chronic group, P < 0.05). However, the glomerular ultrafiltration coefficient, Kf, was changed only in the chronic group (0.1002 +/- 0.0165 to 0.0499 +/- 0.0090 nL/(s.mm Hg), P < 0.05). After Gan treatment, no changes were observed in GFR (1.04 +/- 0.09 to 0.96 +/- 0.08 mL/min, with the maintenance of RPF (2.57 +/- 0.36 to 2.66 +/- 0.34 mL/min) and a nonsignificant reduction in TRVR (28 +/- 3 to 20 +/- 3 mm Hg.min/mL. The short-term Gan treatment also showed a different pattern in glomerular hemodynamics by inducing an elevation in SNGFR (38.7 +/- 5.7 to 50.3 +/- 2.8 nL/min, P < 0.05) with no changes in QA (150 +/- 30 to 135 +/- 22 nL/min) and a mild vasodilation, RT (3.7 +/- 0.5 to 2.7 +/- 0.3 x 10(10) dyn.s.cm-5, P < 0.05) associated with an increment in Kf (0.1002 +/- 0.0165 to 0.2400 +/- 0.0700 nL/(s.mm Hg), P < 0.05). Thus, ACV induced acute renal failure by reducing GFR and SNGFR by an increase in TRVR and RT with a reduction in RPF and QA. Also, after short-term treatment with ACV, a reduction in Kf led to a reduction of SNGFR. On the other hand, Gan treatment did not induce acute renal failure by the adopted techniques.

Reproducibility of fine-needle aspiration biopsy in the diagnosis of acute rejection of renal allografts.

BACKGROUND: Although it has been used as a diagnostic tool in many renal transplant centres the reproducibility of fine-needle aspiration biopsy (FNAB) has not been critically evaluated. METHODS: In the present study material sequentially obtained from 15 patients (177 aspirations) over a 3-month period following renal transplantation was evaluated by two independent observers. Intraobserver reproducibility was studied through the analysis of two evaluations by observer 1 performed 8 months apart. Interobserver reproducibility was calculated comparing the second evaluation of observer 1 with the evaluation of observer 2. All evaluations were performed blindly. Slides and protocols of individual patients were chronologically arranged and thus interpreted. Representation, total corrected increment (TCI), accuracy, and the percent agreement for the diagnosis of acute rejection were evaluated. RESULTS: No intraobserver statistically significant differences were observed. Differences observed in interobserver evaluation of TCI either during, or out of acute rejection episodes, well as the representative quality of the sample and accuracy, were not statistically significant. The percent of agreement for the presence or absence of acute rejection was 77.5% for the intraobserver comparison and 76.7% for the interobserver evaluation. Both values showing either a non-significant value for the difference or a statistical significance for the concordance. CONCLUSION: We concluded that FNAB is an accurate method with fairly good intra- and interobserver reproducibility for the diagnosis of acute rejection of renal allografts.

[Recurrent hematuria in children: study of 250 cases]. / Hematúria recorrente na infância: estudo de 250 casos.

In order to analyse the etiology of recurrent hematuria in childhood, we studied 250 children, referred to our Service (age: 6 mo-17 ys; 102 female and 148 male). They were submitted to the following protocol: urine analyses, uroculture, serum total and fraction complement, electrophoresis of hemoglobin, serum creatinine, BUN, 24h urinary calcium, uric acid and protein, oral calcium load test in children with hypercalciuria (UCa greater than 4mg/kg/day). Radiological evaluation and renal percutaneous biopsy was performed when necessary. The following diagnostic distribution was obtained: Alport syndrome, 19; Berger disease, 15; other glomerulopathies, 45; hypercalciuria, 67; uric acid hyperexcretion, 10; nephrolithiasis, 27; urinary tract infection, 14; renal malformation, 8; no diagnosis, 43. Based in these results, we conclude that appropriate investigation on recurrent hematuria, leads to determination of etiology in over 80% of cases.