Pyelonephritis Xantogranulomatosa: Presentation of Two Cases

The authors present 2 cases of Pyelonephritis xantogranulomatosa treated in the Clinic. This is a very rare form of chronic kidney inflammation with an unclear cause.

The literature shows the relationship of the disease with disorders in urinary outflow, urolithiasis, infections and prolonged antibiotic therapy.

The first patient was found to have doubled kidney and deposits in the kalyxes changed by inflammation. Both patients in the period preceding the diagnosis were subjected to long-term antibiotic therapy due to recurrent respiratory infections and chronic urinary tract infection.

Treatment of the first patient was one-stage due to the intensification of the inflammatory process at the time of diagnosis. In the second girl, the abscess was initially drained, and due to the non-characteristic intraoperative image, the suspicion of xantogranulomatosis was made and confirmed in computed tomography. In the next stage, due to the expansion of the process - nephrectomy was performed.

Proteus mirabillis and Escherichia coli were found in the cultures, which are also reported in the literature as the most common pathogens. It is interesting that despite the generalized inflammatory reaction, only one kidney is involved in the process.

The diagnosis of Pyelonephritis xantogranulomatosa is difficult.

In imaging studies, the kidney is enlarged, with a preserved shape, contains deposits in the calyx and pelvic system and numerous hypoechogenic changes indicating abscesses. Urography and renoscintigraphy may show a weak or inactive organ function. The test of choice is computed tomography, which allows to assess the advancement of the process.

In differential diagnosis in children, the Wilms tumor, neuroblastoma, clear cell carcinoma, inflammatory process like pyelonephritis, kidney tuberculosis, kidney abscess should be considered.

In both described cases, the diagnosis of xantogranulomatosis was confirmed in histopathological examination. Qualification for nephrectomy was based on imaging studies (CT) and persistent high exponents of infection. In the follow up no complications were noted, the remaining kidney in both cases is functioning properly.