[New Guidelines for Hematuria Diagnosis and Future Perspectives on Urinalysis -Chairmen's Introductory Remarks -].

Although microscopic hematuria examinations to obtain information on erythrocyte morphology tend to be influenced by subjective views, these views can be corrected to some extent according to the procedures stated in the JCCLS GP1-P4, standards guideline for urinary sediment examination 2010. Since the accura- cy of FCM (flow cytometry) technology is high, FCM-based assessment should be further promoted in rou- tine practice. Furthermore, technicians in charge of urine tests should exert efforts to achieve a better understanding of the diagnostic guidelines for hematuria and respond to clinicians' requests. The new diagnostic guidelines for hematuria are an achievement at an international level, although they are several challenges to be addressed, and routine practice in laboratories and the active involvement of clini- cians are expected to significantly contribute to hematuria diagnosis and treatment. [Review].

Atazanavir-induced urine crystals demonstrated by infrared spectroscopic analysis.

Atazanavir sulfate, an azapeptide inhibitor of HIV protease, has been associated with urolithiasis. A 60-year-old man with atazanavir-induced urinary sediment crystals verified by infrared spectroscopic analysis is described. He had been receiving highly active antiretroviral therapy (HAART) for HIV infection and also had a history of urinary lithiasis and been undergoing urinalysis once every month. Needle-shaped crystals were seen in his urine sediment and infrared spectroscopic analysis revealed that these were atazanavir crystals. Because the presence of the crystals in urine do not always reveal an abnormality in the urinary test strip analysis, the urinary sediment needed to be observed microscopically in order to prevent future urolithiasis and renal failure in this HIV patient receiving atazanavir.

[Clinical significance of hyaline casts in the new CKD risk classification (KDIGO 2009)].

Chronic kidney disease (CKD) significantly contributes to the increased number of dialysis patients with end stage renal disease. A new CKD risk classification (KDIGO 2009) established in 2011, which is defined by albuminuria and estimated glomerular filtration rate (eGFR) values, demonstrates the relative risks of CKD in great detail. In this study, we evaluated the clinical significance of urinary casts by categorizing a risk Group 1 to 5 according to the KDIGO 2009 classification. In the high risk CKD group (risk group 3 and over), we found a significantly higher number of patients who had > 100 hyaline casts/whole field (WF) in their urine than those that had < 100 hyaline casts/WF. Further, we determined the diagnostic accuracy for the high risk CKD group when the cutoff value for the number of hyaline casts was set at > or = 100 hyaline casts/WF (sensitivity: 44.7%, specificity: 96.5%). The eGFR value was significantly lower in the group with > or = 100 hyaline casts/WF, particularly in hypertensive patients, than that in the group with < 100 hyaline casts/ WF. Of interest is that the eGFR value was significantly lower in patients with 100-999 hyaline casts/WF and > or = 1,000 hyaline casts/WF than that in patients with < 100 hyaline casts/WF in A1 stage. Thus, our present study suggests that the presence of > or = 100 hyaline casts/WF indicates decreased eGFR, and the urinary casts counting may be important and useful for the screening and early detection of high-risk CKD.

[Urinary protein to creatinine ratio and urinary sediments are useful for the screening of chronic kidney disease].

Chronic Kidney Disease (CKD) is an important risk factor of the End Stage Renal Disease (ESRD). In this study, we investigated whether the protein to creatinine ratio (the ratio of P/C) determined by the semiquantitative urinary stick test and urinary sediments are useful for the early detection of CKD. One hundred sixty patients were classified to four or five groups by P/C ratio and various biochemical markers were analyzed. As a result, the 300 mg/g x Cr of P/C group showed a significantly increased serum cystatin C level. The positive rate of the P/C ratio in CKD stage was significantly increased compared with the conventional protein qualitative analysis. Further, the amounts of urinary sediments in CKD stage 1 to 2 were increased, such as hyaline cast, and pathological casts were increased in CKD stage 3 to 5. Thus, our present study suggests that the ratio of P/C and urinary sediments are useful for the screening of CKD.

Prediction of Early BK Virus Infection in Kidney Transplant Recipients by the Number of Cells With Intranuclear Inclusion Bodies (Decoy Cells).

BACKGROUND: BK virus (BKV) is the cause of nephropathy. Because BKV nephropathy can progress to graft loss, early diagnosis of BKV infection is very important. In this study, we aimed to investigate the utility of quantifying cells with intranuclear inclusion bodies (decoy cells) in urinary sediment for the screening and monitoring of BKV infection in renal transplant recipients at our hospital. METHODS: This was a retrospective single-center study. Urine sediment examination was performed at each outpatient visit, and the number of decoy cells was measured in the whole microscopic field. Patients (n = 41) were divided into the BK viremia group (blood positive for BKV DNA by polymerase chain reaction [PCR]) and non-BK viremia group (blood negative for BKV DNA by PCR), and the decoy cell count in urinary sediments was examined. RESULTS: The maximum decoy cell count was significantly higher (P = 0.04) in the BK viremia group than in the non-BK viremia group. In the receiver operating characteristic curve for the maximum decoy cells, the cutoff value was 507 cells. The area under the receiver operating characteristic curve was 0.8774 (95% confidence interval, 0.7739-0.9810). The number of decoy cells at the time of appearance in the BK viremia group was not significantly different from that in the non-BK viremia group. However, the BK viremia group showed an increasing trend, whereas the non-BK viremia group showed a decreasing trend, in the number of decoy cells. There was a positive correlation between the number of decoy cells and the data from the urine BKV-DNA PCR quantification (correlation coefficient [r] = 0.74). CONCLUSIONS: Measurement of decoy cells in urinary sediments may predict early BKV infection, and if performed quickly, it may be useful for screening and continuous monitoring of BKV infection in renal transplant recipients.