Acute pyelonephritis and vesicoureteral reflux are relatively common in children, especially newborns. In 50 to 60% of children, reflux and inflammation lead to irreversible damage to the renal parenchyma. Although these complications are well described in children, there are a limited number of studies assessing the risk of late complications of acute pyelonephritis in adults. Therefore, it is not yet known whether it is necessary to conduct a thorough examination of patients who have suffered from acute pyelonephritis.

The aim of the study was to assess the incidence of late complications in women treated for acute pyelonephritis. The study had two unique characteristics. First, a scan using (TC99M-DMSA) was used. Second, this study had one of the longest observation periods among the studies of women with acute pyelonephritis.

The medical records of all women treated between January 1982 and December 1992 were studied with the following diagnoses: acute pyelonephritis, UTI, urosepsis, renal abscess, perinephric abscess, xanthogranulomatous pyelonephritis.

Acute pyelonephritis was determined by the presence of 4 or more clinical or laboratory signs and a positive bacteriological result. Clinical data included fever, dysuria, rapid urination, pain in the suprapubic area, lower back or abdomen. Laboratory signs included pyuria, a positive result of a bacteriological analysis of the urine or (if sterile), the detection of a uropathogenic microorganism in the blood.

A total of 63 (31%) of the 203 women previously hospitalized for uncomplicated pyelonephritis were examined. Most of them were between 40 and 50 years old at the time of their examination, and an average of 16 to 17 years had passed since hospitalization for acute pyelonephritis. Medical history, current laboratory tests have been studied and a survey has been conducted to identify renal nephrosclerosis. Scanning with Terc 99m labeled with dimercaptosuccinic acid (TC99M-DMSA) revealed that 29 (46%) of the 63 patients had scarring changes in the kidneys, according to these data, the patients were divided into two groups: 1st group - with nephrosclerotic modifications, 2nd group without nephrosclerotic modifications. 13 out of 29 women had a lesion on the right side, 15 on the left side, 1 - bilateral. A large percentage of the changes detected can be explained by the high sensitivity of the scintiography with Tc99m-DMSA. This research method allows the most effective detection of scar changes in the kidneys, compared to ultrasound or intravenous urography. Kidney ultrasound revealed abnormalities in 6 patients in each group. It was nephrolithiasis, renal hypertrophy, doubling of the ureter. Ultrasound nephrosclerosis was detected in only one patient. Due to the fact that the study was not conducted during hospitalization and immediately afterwards, researchers cannot judge the timing of the onset of nephrosclerotic changes and the speed of their progression immediately after and by disease. the following. The study found that the information obtained by scintography was correlated with clinical symptoms and laboratory data. The localization of pain and a decrease in kidney function coincided with the localization of scar changes. It is this fact that suggests that the changes identified by the researchers are associated with previously transferred acute pyelonephritis.

The study attempted to identify the risk factors leading to the development of the above changes. The presence of UTI before or after this hospitalization did not affect the development of nephrosclerosis. The other consequences of acute pyelonephritis also did not depend on the severity of the clinical picture.

The presence of pregnancy was one of the predisposing factors and increased the likelihood of nephrosclerosis by about 4 times. The vast majority of women in the first group were pregnant during hospitalization (65.5% vs 29.4%; p = 0.004). Patients with a serum albumin level lower than 3.2 g / dl subsequently had a risk of scarring 12.5 times more than patients with a albumin level higher than 3.2 g / dl. Women who had scar changes were younger than those who did not have scar changes in the kidneys (mean age 26.6 vs 35.0; p = 0.005). Hypertension then occurred in approximately one in five patients, regardless of the presence or absence of scar changes in the renal parenchyma.

The relationship between the presence of scar changes and a decrease in glomerular filtration is noted. The average level of glomerular filtration in the group with changes in the kidneys was 88 ml / min, which is significantly lower than that in the second group, however, these changes were practically not manifested clinically.

Based on the above data, the researchers conclude that the risk of developing scar changes in the kidneys after acute pyelonephritis in adult women is high. However, clinically significant kidney damage within 10 to 20 years of acute pyelonephritis is rare. The Tc99m-DMSA scan can be used to detect kidney scars in adults, but it is not necessary to use it in daily practice.