No way in & no way out: a case of renal failure due to both pre- and post-renal obstruction

Abstract

A 46-year–old lady presented to the renal physicians in 2002 with a biopsy diagnosis of Langerhans cell histiocytosis (LCH). Initial presentation had been with maxillary and retro-orbital disease. A CT scan of the thorax/abdomen/pelvis in 2002 had shown extensive irregular soft tissue around and extending into the sinuses of both kidneys (Figure 1), with renal calyceal but not pelvic dilatation, as well as disseminated involvement including bone, mediastinum and lungs. Her serum creatinine was normal and a MAG3 renogram showed no evidence of functional obstruction. She had no symptoms other than occasional loin discomfort. Three years later she developed worsening hypertension, a rising serum creatinine and pulmonary oedema. MR angiography showed bilateral tight renal artery stenosis. It again showed the unusual pattern of strikingly dilated calyces but collapsed renal pelves. Dynamic renography and antegrade pyelography (Figure 2) indicated obstruction at the level of the renal pelvis bilaterally. Consequently, percutaneous nephrostomies were placed, but there was no improvement in renal function.