Aim: The incidence of renal abscess ranges from 1-10 cases per 10,000 hospital admissions. Spread of infection can affect the vital structures. Once infection spreads to the perinephric spaces, percutaneous or open surgical drainage is required. In our nephrology department, we had in 3 months 5 cases with clinical suspicion of kidney abscess diagnosed as focal pyelonephritis(FP), ultrasound (US) being the most important for the early diagnosis.
Method: Five cases were admitted with the diagnosis of acute pyelonephritis. They were characterized by lombar pain, fever, low urinary symptoms. In this cases we always perform US in order to exclude other kidney pathology. We performed US at the presentation and after 5 days of unchanged clinical status: persistence of fever and lombal pain. CT scan was also performed.
Results: All cases had positive urinary culture with E Coli and Klebsiella. Initial US revealed unilaterally moderately enlarged kidney with hypoechoic areas in four patients. One patient had focal hipovascularisation. The second sonogram revealed an hypoechoic area, with pour vascularisation in the middle of the parenchyma, ranging from 2 to 5 cm in length. CT scan described same changes. In order to avoid evolution to kidney abscess, combined i.v. antibiothic therapy was immediately applied and clinical status of the patient improved rapidly.
Conclusion: Ultrasound had an important role in early detection of FP and in prevention of an kidney abscess. Repeted sonograms in patient with uncertain clinical evolution of an FP are necessary, being non-invasive, cost-effective and easy to perform.