Una lesión en el cintigrama renal DMSA 6 meses post fase aguda de una pielonefritis representa siempre una cicatriz: un debate abierto / Evolution of scintigraphic renal lesions in children after an episode of acute pyelonephritis

Background: Abnormal Dimercaptosuccinic acid (DMSA) renal scintigraphy performed six months after an acute pyelonephritis (AP) is generally interpreted as scarring. Aim: To perform a follow up of childhood patients showing scintigraphic renal lesions during the acute phase of pyelonephritis (within 7 days from the beginning of fever). Material and Methods: A scintigraphic control was carried out at 5-7 months and, in case of persistent lesions, an additional late scintigraphy at 10-13 months. All patients were followed clinically for one year and those with a relapse of urinary tract infection were excluded from the study. Results: Eighty five patients with a median age of 8 months were included. Among these, the first scintigraphic control was normal in 59 (69%) and abnormal in 26 patients (31%). In five of these 26 patients (5/26:19%-5/85: 6%), a considerable regression of the lesions was obvious on the early control, and normalized completely on the late control. When expressing the results in kidney units, 107 showed lesions during the acute phase of infection; 69% was normal at the early control. Thirty three showed lesions persisting at the early control (31%) and 7 out of these 33 (21%) became normal on the late control (7/107: 7%). In total, 25% of the children included in the study (24% of the kidney units) remained with renal sequelae one year after the initial episode of AP. Conclusions: The persistence of scintigraphic lesions six months after an episode of AP, does not necessarily correspond to permanent scars, since normalization can sometimes be observed on late controls.

[Evolution of scintigraphic renal lesions in children after an episode of acute pyelonephritis]. / Una lesión en el cintigrama renal DMSA 6 meses post fase aguda de una pielonefritis representa siempre una cicatriz: un debate abierto.

BACKGROUND: Abnormal Dimercaptosuccinic acid (DMSA) renal scintigraphy performed six months after an acute pyelonephritis (AP) is generally interpreted as scarring. AIM: To perform a follow up of childhood patients showing scintigraphic renal lesions during the acute phase of pyelonephritis (within 7 days from the beginning of fever). MATERIAL AND METHODS: A scintigraphic control was carried out at 5-7 months and, in case of persistent lesions, an additional late scintigraphy at 10-13 months. All patients were followed clinically for one year and those with a relapse of urinary tract infection were excluded from the study. RESULTS: Eighty five patients with a median age of 8 months were included. Among these, the first scintigraphic control was normal in 59 (69%) and abnormal in 26 patients (31%). In five of these 26 patients (5/26:19%-5/85: 6%), a considerable regression of the lesions was obvious on the early control, and normalized completely on the late control. When expressing the results in kidney units, 107 showed lesions during the acute phase of infection; 69% was normal at the early control. Thirty three showed lesions persisting at the early control (31%) and 7 out of these 33 (21%) became normal on the late control (7/107: 7%). In total, 25% of the children included in the study (24% of the kidney units) remained with renal sequelae one year after the initial episode of AP. CONCLUSIONS: The persistence of scintigraphic lesions six months after an episode of AP, does not necessarily correspond to permanent scars, since normalization can sometimes be observed on late controls.

[Tc 99M DMSA scintigraphy in children with a first episode of acute pyelonephritis: correlation with laboratory tests, echography and the presence of vesico-ureteral reflux]. / Cintigrama renal DMSA en niños con primera pielonefritis aguda: correlación con exámenes de laboratorio, ecografía y la presencia de reflujo vésico ureteral.

BACKGROUND: Tc99m DMSA (dimercaptosuccinic acid) scintigraphy has a high sensitivity for the detection of cortical kidney damage. AIM: To evaluate the Tc99m DMSA renal scintigraphy in children with a first episode of acute pyelonephritis and its association with laboratory parameters, kidney ultrasound and vesicoureteral reflux. PATIENTS AND METHODS: We studied 143 children (age range 8 days, 12 years, 66% female) hospitalized with the clinical diagnosis of acute pyelonephritis (first episode) with a positive urine culture and a renal scintigraphy performed within seven days of diagnosis. DMSA was considered the gold standard for the detection of cortical lesions. Its results were related to the presence of fever, C-reactive protein (CRP), erythrocyte sedimentation rate (VHS), white blood count (WBC), ultrasound examination and vesicoureteral reflux. RESULTS: Seventy nine percent of the population had an abnormal DMSA scan. There were no differences between sex, age and laboratory parameters in children with normal or abnormal DMSA scans, except for CRP (p <0.005). Ultrasound was coincident with the scan in 32% of patients. Eighteen percent had vesicoureteral reflux. CONCLUSIONS: There is a high proportion of abnormal DMSA scans in children with a first episode of acute pyelonephritis.