Gunilla Lidin-Janson

Urinary infection, reflux and renal scarring in females continuously followed for 13-38 years.

This study describes the pattern of urinary tract infections (UTI) in 87 females prospectively followed for a median of 23 years from their first recognized symptomatic infection in childhood. At 16 years of age they were selected for follow-up into adulthood because of renal scarring (reflux nephropathy) in 45 and recurrent UTI in 42. The attack rate (number of urinary tract infections per individual per observation year) was highest during the 1st year of life (1.9), with a gradual decrease to the lowest rate (0.2) at age 11–15 years. A moderately increased attack rate (0.4), was seen in the late teens, extending through to the mid twenties. The proportion of infections having a pyelonephritic character decreased with age and number of infection episodes, but not in females with severe renal scarring. Pyelonephritic infections were correlated with vesicoureteric reflux, and renal scarring to low age at the index infection, total number of pyelonephritic episodes and reflux. Females with renal scarring continued to have a high proportion of pyelonephritic recurrences after 10 years of age, implying that they risk progressive renal disease and should be closely followed into adulthood.

Girls prone to urinary infections followed into adulthood. Indices of renal disease.

This study describes blood pressure and renal function, as well as indices of renal disease, in females with and without renal scarring followed from their first urinary tract infection (UTI) in childhood. Of the 111 patients with a median follow-up time of 15 years, 54 had renal scarring (reflux nephropathy) on urography, which was severe in 19 and moderate in 35. The glomerular filtration rate was lower in patients with severe renal scarring and correlated with renal area on urography. However, the filtration rate was decreased below the lower reference limit in only 7 patients, with a lowest value of 70 ml/min per 1.73 m2. The diastolic blood pressure was higher in women with severe scarring. Hypertension of at least 140/90 mmHg was diagnosed in 3 of 54 (5.5%) females with renal scarring, 2 before and 1 at the follow-up examination. The excretion of albumin in urine was low and not correlated to filtration rate. Tubular enzymes in urine were similar in all groups. Thus the renal function was well preserved and the incidence of hypertension low. Within this range of renal function, the level of albumin in urine did not predict the degree of renal scarring.

Detection of urographic scars in girls with pyelonephritis followed for 13-38 years.

Abstract We report the detection and progression of renal scars in girls prospectively followed from their first recognized urinary tract infection. There were 107 infection-prone subjects with a median age of 7.1 years at the first and 21.7 years at the last urography. Of 51 females who ultimately had lesions, 38 had established scars at the first urography. In 18 subjects, new scars were found in previously undamaged kidneys, 5 already with unilateral scarring. There had been a normal urography after the 5th birthday in 8 of those with later scarring. Worsening of scarring was seen in 10 of the 38 subjects with established scars. The renal damage was in most cases slight or moderate. By stepwise logistic regression analysis, grade of reflux and number of pyelonephritic attacks correlated with scarring, and number of pyelonephritic attacks with new scars and worsening of the lesions. In summary, of the females who ultimately had renal lesions, one-third developed new scars. In most of those with established scars at the first urography, the focal character of lesions suggests that most were also acquired. Since reflux and number of pyelonephritic attacks were identified as risk factors, prevention of renal deterioration should be possible.

Host Response in Women with Symptomatic Urinary Tract Infection

The agreement between clinical signs and host response was analysed in 174 women with symptomatic urinary tract infection. C-reactive protein (CRP) confirmed the clinical diagnosis in that 94% of non-pregnant and 91% of pregnant women with acute pyelonephritis had serum levels greater than or equal to 30 mg/l, compared with only 5% of cystitis patients. There was a significant increase in the erythrocyte sedimentation rate (ESR) and reduction of the renal concentrating capacity in patients with acute pyelonephritis, although the overlap with the cystitis group was greater than for CRP. The transient decrease in urine osmolality was unrelated to age, as were CRP, ESR and the total white blood cell count. Pregnant women had higher ESR but lower CRP levels than non-pregnant women with acute pyelonephritis. The renal concentrating capacity was more reduced in those infected with Escherichia coli expressing adhesins specifically recognizing Gal alpha 1----4Gal beta-containing receptors on uroepithelial cells.

Long-Term Pattern of HIV-1 RNA Load in Perinatally Infected Children

The objective of this study was to describe the natural history of HIV-1 RNA load in vertically HIV-1-infected children. HIV-1 RNA in 156 plasma or serum samples (1-14, median 4 from each child) from 32 vertically HIV-1-infected children was detected with the NASBA technique (Organon Teknika, The Netherlands). Twenty-one children were prospectively followed from birth, and 11 were identified and included at the age of 7-89 (median 61) months. The highest numbers of HIV-1 RNA copies were seen at 1.5-3 months of age. A quadratic curve model showed a reduction of HIV-1 RNA with increasing age up to approximately 8 years, and thereafter increasing numbers, p(age) = 0.002, p(age2) = 0.008. This pattern was not typical for individual children in whom a great variation in HIV-1 RNA numbers was seen over time. The interval from birth to the first HIV-1 RNA peak ranged from 1.5 months to more than 2 years. The HIV-1 RNA levels remained relatively high and fluctuating over the years in symptomatic as well as in long-term asymptomatic children. This makes HIV-1 RNA determination in children more difficult to use than in adults, as the only tool for prediction of disease progression and for initiation of therapy.

Selective Use of Excretory Urography in Women with Acute Pyelonephritis

The outcome of excretory urography was analyzed in 103 nonpregnant women followed prospectively after community acquired acute pyelonephritis. Radiological abnormality was found in 40 per cent of the patients (17 per cent had major abnormalities, including renal scarring, calculi and obstruction). All 5 women with surgically correctable lesions had rapid bacteriological relapse or recurrent acute pyelonephritis. Neither a history of urinary tract infection, the acute inflammatory response nor infection due to Escherichia coli with or without adhesins specific for Gal alpha 1----4Gal beta-containing receptors was efficient in predicting major radiographic lesions or the outcome of treatment. Bacteremia was detected in 27 per cent of the patients but in the absence of obstruction. These results suggest that excretory urography is dispensable in most women with acute pyelonephritis, and that those needing such investigation may be identified by failure to respond to antibiotic treatment or by the recurrence pattern.

Bacterial Adhesion as an Indicator of Renal Involvement in Bacteriuria of Pregnancy

The association of bacterial virulence with the host response to bacteriuria was evaluated in 70 pregnant women with acute pyelonephritis or bacteriuria detected at screening. Patients infected with Escherichia coli attaching to Gal alpha 1----4Gal beta-containing receptors, had significantly higher levels of C-reactive protein and lower renal concentrating capacity than patients infected with strains lacking this specificity. The renal concentrating capacity ranged from 419-1151 mOsm/kg in the women with bacteriuria on screening. 5/11 women with a renal concentrating capacity less than or equal to 784 mOsm/kg were infected with Gal alpha 1----4Gal beta-specific bacteria, compared to 0/16 of patients who concentrated the urine greater than 784 mOsm/kg. According to earlier studies the risk for progression to pyelonephritis and recurrences during pregnancy was increased in bacteriuric women with a reduced renal concentrating capacity. The present study demonstrates that this risk group can be identified in part by the properties of the infecting E. coli strains.