Pus Cell and Bacterial Counts in the Diagnosis of Urinary Tract Infections in Childhood

Abstract

The techniques used to examine urine with a view to determining whether or not it is infected vary widely. Although the results produced at any one hospital are usually reproducible and, with experience, interpretable, it is often difficult or impossible to compare accurately these findings with those of any other hospital. This state of affairs is sufficiently disturbing, but there also exists doubt as to whether assessment of pyuria (Stansfeld and Webb, 1953;Stansfeld, 1962) or bacteriuria (Kass, 1956(Kass, , 1957Sanford, Favour, Mao and Harrison, 1956;Pryles, 1960) is better as an indication of infection of urine.These considerations have prompted an investigation into the techniques used to distinguish the presence of a urinary infection and in particular to compare the value of pus cell and bacterial counts and the influence the technique of collection exerts upon them. Selection of PatientsUrine specimens were collected, using several different techniques from two groups of patients.Group I: Infants and children admitted to hospital with conditions other than urinary infection, renal disease or conditions known to affect the cellular or bacterial content of the urine and who were not receiving antibiotic therapy.Group II: Patients whose clinical condition was compatible with a diagnosis of acute urinary infection and from whom the specimen was collected before therapy was undertaken.It is realized that children in Group I were not necessarily 'normal' with respect to their urinary findings, in that they were sick, but it was to distinguish just such children from those who were sick because of a urinary infection that this investigation was primarily undertaken.It is therefore felt that Group I represents a fair control group for comparison with patients suffering from urinary infections.All these specimens were then examined and pus cell and bacterial counts performed on each one. TechniquesIn children of both sexes, who were sufficiently old to be co-operative (usually more than 3 years old) clean specimens of urine were obtained by first thoroughly swabbing the genital skin with an antiseptic solution (aqueous 0 1% chlorhexidine or 1% cetrimide); the child was asked to void urine into a sterile container, and the specimen was immediately refrigerated. At a later stage of the investigation a special sterilized glass tube ( Fig. 1) was used to collect clean specimens from girls, the expanded end of the tube being held over the urethral orifice during micturition; the technique was otherwise as above.In infants and toddlers, those unable or unwilling to co-operate, other techniques were tried. In male infants, after the usual thorough sterilization of the genital skin and glans penis, either a piece of sterilized (autoclaved) Paul's tubing (i in. flat width) with a knot in the distal end or a clean (not necessarily sterile) disposable plastic urine collection bag (Downs) was fixed in position by adhesive plaster. In female infants either a similar plastic bag or another special sterilized glass collector ...

Clinical and Radiological Features of Urinary Infection in Childhood

“…The relative merits of different bacteriological techniques (Kass, 1957;Pryles, 1960;Guttmann and Stokes, 1963) and the place of urine white-cell counting (Stansfeld and Webb, 1953;Houston, 1963) have been extensively studied and reviewed. In our experience, laboratory confirmation of the diagnosis rarely presents difficulty provided a fresh clean specimen of urine is collected before treatment is started.…”

Measurement of pyuria in urinary tract infections.

“…of uncentrifuged urine represents gross pyuria; normal urine rarely contains > 10 pus cells/cu.mm. (Stansfeld and Webb, 1953;Linneweh, 1957Linneweh, , 1958Stansfeld, 1962;Zapp and Jung, 1963;Houston, 1963;Braude et al, 1967).…”

“…Pus cell counts were performed on fresh uncentrifuged, well-mixed urine in a Fuchs-Rosenthal counting chamber (Houston, 1963). The result was expressed as pus cells/cu.mm.…”

Pyelonephritis in Children

“…The most precise results are obtained from suprapubic aspiration of the bladder (Monzon, Ory, Dobson, Carter and Yow, 1958); this method gives only a 93%/0 bacterial correlation with catheter urine, but is higher if the first few millilitres of catheter urine are discarded, (Pryles, 1960). Many different,techniques of perineal cleansing are employed before taking clean specimens (Brumfitt and others, 1961;Cattell and Lefford, 1963;Houston, 1964); benzylkonium chloride 1 in 1000 is much used (Little, 1962), polybactrin spray has advocates (McLeod, Mason and Pilley, 1963), but soapand-water seems satisfactory (Clarke, 1960). Different methods of cleansing do not seem to influence urine cell counts (Lincoln and Win-berg, 1964).…”

“…Different methods of cleansing do not seem to influence urine cell counts (Lincoln and Win-berg, 1964). The plastic bags, much used for obtaining specimens from young children, are liable to introduce contamination into bacterial counts, but have less influence on cell counts (Houston, 1964).…”