Pyuria as a screening test for detection of urinary tract infection in patients on long-term hemodialysis

This study was conducted to evaluate the sensitivity and specificity of pyuria detection in centrifuged urine samples of patients on hemodialysis, and its relationship with urinary tract infection. Clean-catch midstream urine samples of 90 hemodialysis patients [34 women and 56 men] were obtained and divided into two parts for examination of urine sediment and urine culture. Pyuria was defined as the presence of more than 10 leukocytes per high-power field of microscope. Ninety patients with a mean age of 52.8 +/- 14.2 and a mean period of dialysis of 3.3 +/- 2.3 years were studied. Forty-five participants had pyuria and only 16 [35.5%] of them had a positive urine culture for infection. Pyuria and urinary tract infection were present in 52.9% and 29.4% of the women and 48.2% and 10.7% of the men, respectively. The sensitivity and specificity of pyuria screening for urinary tract infection was 100% and 61.8%, respectively. The positive and negative predictive values were 35.5% and 100%, respectively. In patients on hemodialysis, because of the low specificity and positive predictive values, samples with positive pyuria should be cultured to confirm urinary tract infections

Effect of allopurinol in decreasing proteinuria in type 2 diabetic patients

Diabetic nephropathy is the most prevalent cause of end-stage renal disease. Besides factors such as angiotensin II, cytokines, and vascular endothelial growth factor, uric acid may play a role as the underlying cause of diabetic nephropathy. We evaluated allopurinol effects on proteinuria in diabetic patients with nephropathy. In a double-blinded randomized controlled trial on 40 patients with type 2 diabetes mellitus and diabetic nephropathy [proteinuria, at least 500 mg/24 h and a serum creatinine level less than 3 mg/dL], allopurinol [100 mg/d] was compared with placebo. Administration of antihypertensive and renoprotective drugs [angiotensin-converting enzyme inhibitors and angiotensin receptor blockers continued for both groups, without changes in dosage. Proteinuria was compared at baseline and 2 and 4 months between the two groups. Each group consisted of 9 men and 11 women. There were no difference between two groups regarding age, body mass index, duration of diabetes mellitus, systolic and diastolic blood pressure, fasting blood glucose, blood urea nitrogen, serum creatinine, serum potassium, and urine volume. Serum levels of uric acid [P=.02] and 24-hour urine protein [P=.049] were significantly lower in the patients on allopurinol, after 4 months of receiving allopurinol, compared with the control group. Low-dose allopurinol can reduce severity of proteinuria after 4 months of drug administration, which is probably due to decreasing the serum level of uric acid. Thus, allopurinol can be administered as an adjuvant cost-effective therapy for patients with diabetic nephropathy

Urinary polymerase chain reaction for diagnosis of urogenital tuberculosis

The aim of this study was to evaluate diagnostic value of urinary polymerase chain reaction [PCR] in urogenital tuberculosis [UTB]. In 33 patients with confirmed diagnosis of UTB by urine culture and/or acid-fast staining, clinical symptoms and laboratory and radiological findings were evaluated. For each patient, 3 consecutive urine samples were examined by PCR for Mycobacterium tuberculosis and the results were compared with the standard microbiological methods and radiological findings. The mean interval between the appearance of the symptoms and the diagnosis was 12.3 A +/- 12.2 months. Symptoms were irritative bladder symptoms such as dysuria and diurnal or nocturnal frequency [51.5%], flank pain [27.3%], microscopic hematuria [18.2%], gross hematuria [9.1%], and suprapubic pain [9.1%]. The laboratory findings included hematuria [27.3%], pyuria [12.1%], and hematuria with pyuria [48.5%]. Diagnosis of UTB was made in 19 patients by positive urine culture for MT in 19 patients [57.6%], positive acid-fast staining in 6 [18.2%], and both in 8 [24.2%]. Intravenous urography showed abnormal findings in 16 patients [61.5%], including pyelocaliceal dilatation [26.9%], ureteral stricture and hydroureter [23.1%], multiple small caliceal deformities [15.4%], severe parenchymal destruction [11.5%], autonephrectomy [11.5%], and calcification [7.7%]. Urinary PCR was positive in 16 patients [48.5%] and in 10 [62.5%] with abnormal findings on intravenous urography. A high index of suspicion is necessary for diagnosis of UTB even in patients with nonspecific manifestations. Urinary PCR is recommended for instant diagnosis and screening before further examinations, but it cannot be the sole diagnostic modality for diagnosis of UTB