Renal cysts are common, particularly in individuals over 50, and are often asymptomatic. Spontaneous rupture of these cysts, especially without trauma, is a rare occurrence. We present the case of a 51-year-old female with a history of recurrent deep vein thrombosis, who initially presented with symptoms of abdominal pain, nausea, and dysuria, which were attributed to a urinary tract infection caused by Escherichia coli. Despite treatment with antibiotics, her condition worsened, and further imaging revealed a 4.5 cm renal cyst with features suggestive of rupture. After percutaneous aspiration of the cyst, the culture results revealed E. coli, confirming the diagnosis of spontaneous rupture of an infected renal cyst. The patient showed significant improvement with continued antibiotic therapy. This case underscores the rarity of spontaneous renal cyst rupture in the setting of an active urinary tract infection and highlights the importance of early recognition and appropriate management to ensure favorable outcomes.
Keywords: Escherichia coli; Percutaneous drainage; Pyelonephritis; Renal cyst; Spontaneous rupture.
© 2025 The Authors. Published by Elsevier Inc. on behalf of University of Washington.
