The finding of chronic pyelonephritis in males and females at autopsy

Retrograde Proteus pyelonephritis in rats. Localization of antigen and antibody in treated sterile pyelonephritic kidneys

Rats with retrograde proteus pyelonephritis were treated with antibiotics until their kidneys became sterile. Using fluorescent antibody techniques, specific P. mirabilis antigen was found in some sterile pyelonephritic kidneys 20 weeks after cessation of treatment and presumed renal sterilization. Persistent antigen was associated with interstitial chronic inflammation but not with acute inflammation or progressive scarring. Rat gamma globulin and proteus antibody were localized in plasma cells of the renal inflammatory infiltrates. It is suggested that persistent antigen in chronic pyelonephritis may lead to the continued local appearance of antibody-producing cells.

Urinary tract infections. Old and new concepts

The recommendations for evaluation and management of pediatric patients with UTIs are summarized in Table 5. These recommendations were designed to minimize the risk of kidney damage in children with UTIs based on current perceptions of the pathogenesis of renal injury. The children at greatest risk for kidney damage are the infants and young children with febrile UTIs in whom effective treatment is delayed, those with gross VUR, and those with anatomic or neurogenic urinary tract obstruction. These recommendations likely will be modified as more is learned about the pathogenesis of renal injury associated with UTIs, as new therapeutic approaches are developed, and as imaging technology improves.

Vesicoureteric reflux and renal injury

Renal injury associated with the intrarenal reflux (IRR) of urine that is either infected, under high pressure, or both, is a major cause of severe hypertension during childhood and adolescence and of chronic renal insufficiency in patients less than 30 years of age. Many, but not all, adolescent and adult patients with reflux nephropathy (RN) give a history of urinary tract infection (UTI) or unexplained fevers in infancy or early childhood, when the kidney is thought to be at greatest risk of injury. Although vesicoureteric reflux (VUR) is observed more commonly in infants than children with UTI, it is rare in uninfected patients at any age and should never be considered a normal finding during human development. Renal scarring may not be obvious in radiographic or radionuclear studies to medical management alone, no definite benefit of one over the other was observed, regardless of the grade of VUR. Moreover, progressive renal injury in scarred kidneys has been noted even after VUR had been corrected, when infection had been prevented, and while hypertension had been controlled satisfactorily. Focal glomerular sclerosis, a lesion found in patients with proteinuria and RN, has been identified not only in scarred kidneys, but also may be seen in contralateral, unscarred kidneys without VUR, which might suggest a humoral factor or, perhaps, a hyperfiltration phenomenon. RN is one of the most frequent causes of end-stage renal disease (ESRD) in children, adolescents, and young adults, which is potentially preventable. However, prevention will depend on early identification of patients at risk--infants and young children after the first UTI and siblings of patients with VUR--aggressive and effective treatment of UTI, minimizing intravesical pressure, and education of patients, parents, and physicians.

Yield of screening urography in young women with urinary tract infection

In order to determine the diagnostic yield and therapeutic outcome of screening urography in young women with urinary tract infection, 1000 urographic examinations were reviewed. Of these 96.4% were normal; 1.4% revealed abnormalities that subsequently required therapy. Each treated abnormality was expensive to diagnose; protocols other than universal urography could have made most of these diagnoses. The incidence of treated abnormalities may be no greater in this group than in the general population. Universal screening urography in these patients cannot be definitely recommended.

Renal lesions after unilateral ureterosigmoidostomy in the rabbit: preliminary results

Unilateral ureterosigmoidostomy (U.S.S.) was performed on 15 rabbits and then the animals were sacrificed after 3, 8 and 15 months. The gross appearance of the kidney and radiological investigations revealed enlargement of the pelvis and of the ureter on the operated side although the anastomosis was patent in all cases. In rabbits sacrificed 8 months after U.S.S. an adenomatous polyp was present at the site of anastomosis. Histological examination of the affected kidney showed pyelonephritis secondary to obstruction and immunopathological studies revealed in some rabbits glomerular and tubular deposition of immunoglobulins and complement. The contralateral kidney was always normal. Biochemical investigations showed only a moderate increase in blood urea nitrogen and plasma creatinine values.