All of the following about Xanthogranulomatous pyelonephritis is true Except

Xanthogranulomatous pyelonephritis It is an unusual and rare form of chronic pyelonephritis associated with Proteus infections. MORPHOLOGY Gross: Cut surface shows large, yellowish-orange nodules, which may be confused with renal cell carcinoma. Microscopy: Interstitium shows foamy macrophages, plasma cells, and lymphocytes Clinical Features Chronic pyelonephritis associated with reflux may be a silent onset. Usual symptoms are back-pain, fever, pyuria, and bacteriuria Ref: RAM DAS NAYAK EXAM PREPARATORY MANUAL FOR UNDERGRADUATES 2nd ed. pg no: 619