Infectious urolithiasis
Piotr Skrzypczyk, Małgorzata Pańczyk-Tomaszewska
Infectious urolithiasis is a form of urolithiasis associated with the presence of bacteria in the urinary tract (Proteus spp., Klebsiella spp., Providencia spp., Pseudomonas, Morganella morganii and Staphylococcus aureus). These bacteria produce urease, i.e. an enzyme which decomposes urea. Deposits made of magnesium ammonium phosphate (struvite), sometimes combined with carbonate apatite, can quickly expand, fill the entire renal pelvis and lead to renal failure. In children, struvite urolithiasis has a variable frequency – in 1–29% of all patients with urinary tract deposits. The predisposing factors for the development of this urolithiasis in children are urinary tract defects and neurogenic bladder. Its symptoms are a combination of the symptoms of urolithiasis and urinary tract infection (fever, dysuria, lumbar pain, urinary urgency). In imaging studies, a large branched deposit is often visible, sometimes filling the entire renal pelvis and calyces. Treatment consists of surgical removal of deposits (most often by percutaneous nephrolithotomy) in combination with targeted antibiotic therapy. In Poland, combined treatment (percutaneous nephrolithotomy + ureterorenoscopy) proved to be a very effective and safe method, allowing the removal of large urinary deposits from the urinary tract in children. Antimicrobial treatment without surgical treatment is rarely effective. Other options for non-surgical management include reducing dietary phosphates, acidifying urine, administration of urease inhibitors (in adults) or citrates, and rinsing the renal pelvis with a solution of citrates or hemiacidrin. The prognosis in this group of patients depends mainly on the completeness of the surgical procedure and the lack of relapses.