[Abdominal wall skin nodules revealing xanthogranulomatous pylonephritis]

INTRODUCTION

Xanthogranulomatous pyelonephritis is a chronic pyelonephritis characterized by an inflammatory granulomatous reaction that destroys the renal parenchyma. It is an uncommon entity. Diffuse inflammation has the potential to spread to nearby organs, especially the skin.

OBSERVATION

A 73-year-old patient presented with a three-year history of painful and fistulized nodules on the abdominal wall. The results of abdominal computed tomography and magnetic resonance imaging revealed xanthogranulomatous pyelonephritis with extension to the skin, colon, and psoas muscle. The skin lesions were improved by a double antibiotic therapy. The patient was advised to have a radical left nephrectomy, but he refused surgery and was then lost to follow-up.

CONCLUSION

We report an uncommon case of xanthogranulomatous pyelonephritis revealed by cutaneous nodules of the abdominal wall, with an extension toward the skin, the colon and the psoas muscle.

[Physiological hydronephrosis in pregnancy: Occurrence and possible causes. An MRI study]

INTRODUCTION

The etiology of the uretero-hydronephrosis in pregnancy is just hypothesis: hormonal or mechanical hypothesis, only investigated by echographic studies. MRI permits to visualize the entirety of the urinary tract, which can be helpful to find out a mechanical cause.

METHODOLOGY

We have analysed the MRI of 100 asymptomatic pregnant women. We have determined the number and locations of the uretero-hydronephroses and researched whether there is any relationship between the uretero-hydronephrosis and certain abdominal structures. We focused on the psoas muscle and measured its depth, width and calculated its surface by a reproducible method.

RESULTS

The analysis revealed that the uretero-hydronephrosis was predominantly at the right side (63%) and in the majority of the cases limited to the kidney (42%) and/or the proximal third of the ureter (42%). We were able to rule out some proposed etiologies: a compression of the ureter between the uterus and the iliac or ovarian vessels; a protective effect of the left intestinal structures. A link was observed between the psoas muscle and the physiological uretero-hydronephrosis: the ipsilateral psoas muscle seemed smaller in pregnant women presenting a uretero-hydronephrosis.

CONCLUSION

We have highlighted a link between a physiological uretero-hydronephrosis during pregnancy and a lesser developped psoas muscle. The hypothesis proposed is that a smaller psoas muscle would have a less protective effect of the ureter due to a lesser development. This study offers a practical conclusion: a left sided uretero-hydronephrosis during pregnancy and/or including the entirety of the ureter is more probably a pathological hydronephrosis.

LEVEL OF EVIDENCE

4.