Rapid dipstick test for diagnosis of urinary tract infection.

The rapid dipstick test of urine leukocyte esterase (LE) activity and nitrite has not been studied fully in pediatric clinical situations. We investigated the usefulness of the dipstick LE and nitrite test in the screening of urinary tract infection (UTI) in pediatric patients. Ninety-two fresh urine samples were obtained from children suspected of having UTI. Leukocyte esterase activity and nitrite were measured in the urine specimens read by a photometer. Leukocytes were also counted on a disposable slide. Urine samples were examined for bacteriuria by the standard culture method. The results of the urine dipstick test of LE showed a close relationship with leukocyte counts on a counting chamber. Leukocyte esterase (-) indicated leukocyte counts of less than 10/uL with a probability of 97% (58/60). Of the 22 urine samples with significant bacteriuria diagnosed by standard urine culture, the nitrite test did not detect bacteriuria in 10. While the sensitivities of the dipstick tests of nitrite (+) and LE +/- or more for the diagnosis of significant bacteriuria were 55% (12/22) and 86% (19/22), respectively, the sensitivity and negative predictive value of the combined test were 100%. These results suggest that use of the dipstick test of LE and nitrite can avoid a large part of the cost incurred by urine culture and is useful for screening UTI in children.

Diagnosis of urinary tract infection by urine microscopy using a disposable counting chamber.

Routine urinalysis is performed as a screening test for urinary tract infection (UTI), but is not very reliable. We assessed the usefulness of microscopic examination of unspun urine using a disposable slide with counting chambers for the diagnosis of UTI caused by a variety of species of bacilli. One hundred and seventy-two urine samples were obtained from 113 subjects (60 male and 53 female), including 84 inpatients, aged 20-96 years. The urine samples were examined for bacteriuria and pyuria using a counting chamber, and the reliability of this method in predicting significant bacteriuria defined by routine urine culture and Gram stain of urine smears was analyzed. Significant bacteriuria was diagnosed in 68 urine samples, including 34 from indwelling catheters, from 52 patients mostly having underlying diseases. Only 12 of the positive urine samples contained E. coli, with a variety of other bacilli including cocci found in the rest. The counting chamber method detected bacteriuria in 64 of these 68 positive samples (sensitivity = 94%). Specificity was 88%. While the sensitivity and specificity of pyuria (WBC > 10 microliters-1) were 79 and 71%, respectively, both sensitivity and negative predictive value were as high as 97% when bacteriuria or pyuria was present. We demonstrated that urine microscopy on a disposable counting chamber is a simple, sensitive and time- and cost-saving method for the diagnosis of UTI caused by a variety of bacterial species including cocci.

Epidemiological evaluation of colonic diverticulosis and dietary fiber in Japan.

The incidence of colonic diverticulosis was examined in 5 hospitals geographically isolated from each other in Japan during the period between mid '70s and 1986. The incidence rapidly increased in all hospitals from 3.5-9.0% in mid '70s and 8.4-23.2% in 1986. The ratio of right-sided type colonic diverticulosis was approximately 70-80% in each hospital and the ratio did not fluctuate significantly during the period. Birth cohort analysis revealed that although the incidence of right-sided diverticula had increased with aging, in groups born in more recent decades right-sided diverticula appeared in younger age than other groups. It was suggested that environmental factors rather than congenital factors may cause the increase of the incidence of right-sided colon diverticula.

Human papillomavirus infection of the uterine cervix analyzed by nonisotopic in situ hybridization.

Some types of human papillomaviruses (HPVs) have been suggested to be strongly related to uterine cervical carcinoma. An attempt to detect these in formalin-fixed, paraffin-embedded sections was made by either immunohistochemical or by in situ hybridization. Anticapsid protein of bovine papillomavirus antibody labeled with peroxidase was used for immunohistochemistry, and biotin was used instead of radioisotopes to label probes for in situ hybridization, which resulted in low background and a rapid procedure. Condylomatous changes were stained immunochemically with this antibody even in invasive carcinoma, whereas the carcinoma itself was not stained. Direct correlation was demonstrated by in situ hybridization between the HPV genome and histopathological structure, which was impossible by Southern or dot hybridization. HPV DNAs were detected in the nuclei of koilocytes and dyskeratinocytes of condylomata and dysplasias. Furthermore, hybridization signals of HPV DNAs in basal and parabasal cells suggested that HPV infection had already begun in the basal cells. In the case of malignant neoplasia accompanied by dysplasia, the same type of HPV was detected both in the malignant neoplasia and accompanying dysplasia. In one case of intraepithelial carcinoma, the very small focus of carcinoma just arisen in the cells of dysplasia was identified, and both were positive for HPV 18. This fact supports the suggestion that the carcinoma arises in dysplasia. Invasive carcinomas were classified further into keratinized, large-cell nonkeratinized, and small-cell nonkeratinized types, and the positive frequency for HPV 16 decreased as the differentiation of the carcinoma decreased. In the case of keratinized type of invasive carcinoma, strong hybridization signals were prominent around the malignant pearl formation.