Extrarenal manifestations of severe acute pyelonephritis: CT findings in 21 cases

Abstract

The aim of this study is to report the extrarenal computerized tomography (CT) findings in patients with acute pyelonephritis (APN). Twenty-one CT examinations of 20 patients [19 women and one man, with ages ranging from 18 to 57 years (mean -35.2 years)], presenting either with a clinical diagnosis of APN (n=17) or with a suspected acute appendicitis, fever of unknown origin, and adult respiratory distress syndrome, one in each, were retrospectively reviewed. None had a known preexisting systemic disease. Results showed that renal abnormalities were seen on CT in all patients. In addition, ascites was detected in all women patients associated with subcutaneous edema in five of them. A thickened gallbladder wall was found in 19 cases, all were women, and periportal tracking and a dilated inferior vena cava in 17 CTs. Pleural effusion and thickened interlobular septa were present in 16 and 15 studies, respectively. Relevant laboratory findings included hypoalbuminemia in 14, elevated liver enzymes in 11, hypocholesterolemia in nine, and elevated LDH levels in six cases. In conclusion, radiologists should be familiar with the extrarenal imaging features of APN that may be seen on CT, and on ultrasonography as well, and should look for renal abnormalities to diagnose a clinically unsuspected APN. Alternatively, APN should be included in the differential diagnosis of systemic diseases that cause gallbladder wall thickening to avoid misdiagnosing it as acute cholecystitis.

Freqüência dos sinais de pielonefrite aguda em pacientes submetidos a tomografia computadorizada

“…It is important to note that the majority of the patients in the present study (89%) presented alterations directly related to the acute pyelonephritis presentation, allowing to consider the positivity of this tomographic findings as a result of the renal inflammatory and infectious condition, as already identified by other authors (7) . However, it is important to note that some of these findings, perirenal heterogeneity and collecting system dilatation observed in patients with excretory system obstruction, for example, are non-specific of acute pyelonephritis (26) .…”

“…Until recently, there was only sporadic reports on cases of patients with acute pyelonephritis and gallbladder wall thickening or perivascular fluid (13) and periportal edema (14,15) . Periportal edema had already been described for other conditions such as cirrhosis, hepatitis, liver tumors, biliary tract obstruction, liver and bone marrow transplant, heart failure, abdominal trauma in the pediatric population (14,(23)(24)(25) , and even in acute pyelonephritis (7,15) . In the present study this was a relatively frequent finding, present in one-third of cases.…”

“…Acute pyelonephritis also has been described as a cause for gallbladder wall thickening (7,13) . The present study identified this finding or perivesicular fluid in one-third of cases.…”

“…Few case reports have illustrated the finding of associated extrarenal alterations such as pleural effusion (11,12) , gallbladder wall thickening, perivesicular fluid (13) and periportal edema (14,15) . Until November/ 2006 there was no study in the literature describing a larger series of patients presenting with such extrarenal findings (7) . Despite the fact that tomographic findings in patients with acute pyelonephritis are well known, the frequency of these findings, as well as CT reproducibility, still remains to be clearly established.…”

Imaging of acute cholecystitis and cholecystitis-associated complications in the emergency setting

“…Gallbladder mural thickening is the most common but the least specific finding and may be seen in a variety of other conditions, such as hepatitis, hypoproteinaemia, heart failure and acute pyelonephritis. (6,10,11) Gangrenous cholecystitis results from the downhill course of an episode of acute cholecystitis and occurs in up to 39% of patients with acute calculous cholecystitis. (12) It is associated with higher morbidity and mortality rates than uncomplicated acute cholecystitis.…”