CASE REPORT Spontaneous subcapsular renal haematoma Abstract OJ Solomon MBChB, FFRad(D)SA Spontaneous subcapsular renal haematoma is a rare condition caused by bleeding into the subcapsular or perinephric space in the absence of trauma, bleeding diathesis or anti- coagulation. If the contralateral kidney IS normal, radical nephrectomy is recommended due to a high incidence of small occu It tumours. Case report Constantiaberg Medi-Clinic, Plumstead, Cape Town no history of trauma and he was not taking anti-coagulant therapy. Clini- cally,he was noted to be undistressed, apyrexial and normotensive. The left kidney was feit to be slightly enlarged and 1+ haematuria was noted. His general practitioner suspected renal colic and he was referred for an ex- cretory urogram. There were no ap- parent calcifications on the survey and the right kidney, collecting system and ureter appeared normal. On the left there was no identifiable nephrogram and no excretion was noted at 1 hour. An ultrasound examination revealed alO em solid appearing left renal mass replacing almost the entire left kid- ney, with only a small rim of renal tis- sue noted anteriorly. This was thought to represent a large renal tumour and computed tomography (CT) was per- formed approximately four hours af- ter the excretory urogram. On the pre con trast images, a persisten t nephrogram was noted in the com- pressed and anteriorly displaced kidney. This was due to alO em subcapsular mass showing minor extension into the pararenal spaces (Figures 1-2). No fo- cal abnormality was seen in relation A 74-year-old man pre- sented with a three day history ofleft loin pain radiating to the groin. The pain was not typi- cally colicky in nature and there were no associated con- stitutional symptoms. He had been previously well and besides mild hypertension, there was no past medical history of note. There was Figure 1: Image obtained four hours after IVU showed persistent left nephrogram with kidney compressed and anteriorly displaced by large subcapsular haematoma. Note extension into posterior pararenal space. 18 SAJOURNAL OF RADIOLOGY. April 2000 to the renal parenchyma and the right kidney appeared normal. A large perinephric haematoma was suspected to page 20 Cant Tel: 27 12993 ..2474 27 12 998-7366 Fax: 27 12993-2478 17b Garsfontein Park 645 Jacqueline Drive Garsfontein East 0060 Further information on request from: anene harmaceuticals Reg. no. 95/01988/07 Spontaneous subcapsular rena I baerriarorna (rom page 18 nephrotomography may reveal a displaced kidney with the paren- chyma compressed by haematoma. Ultra- sound findings are usu- ally non-specific and differentiation of a re- nal mass from a ne- phric haematoma may be difficult. CT scan is the investigation of choice and will reveal an abnormal soft tissue mass confined by the renal capsule and compressing the renal parenchyma. This may ex- tend into the perinephric and pararenal spaces with effacement of the normal retroperitoneal structures. Renal angiography to exclude vas- cular lesions such as arteritis, arterio- sclerotic aneurysms, arteriovenous malformations or a small renal cell carcinoma may reveal flattening of the renal parenchyma and displace- ment of the capsular vessels. Of the eight cases reported by Kendall et all six were shown after ne- phrectomy to have small peripheral car- cinomas. Only one of these had suspi- cious angiographic findings whereas the other five tumours were undetectable pre-operatively. In the other two cases no cause was found. Pollack and Popky' reported small peripheral tumours in five of nine patients with spontaneous Figure 2: Post contrast showing compression of renal parenchyma. and confirmed surgically. A radical nephrectomy was performed and close histological examination of the resected kidney failed to reveal a cause for the bleeding. Post-operative course was uneventful and the patient re- mains well. Discussion Spontaneous subcapsular or perinephric haematoma is an uncom- mon clinical problem and occurs in the absence of anti-coagulation, arteri- tis or trauma. The clinical presenta- tion is variable and depends on the severity and duration of bleeding. This may be sudden with acute onset of upper abdominal or flank pain, nau- sea and vomiting or subacute, as in our patient, with symptoms suggestive of renal colic. A low-grade temperature may be present and urinalysis is usu- ally normal. Excretory urography with 20 SAJOURNAL OF RADIOLOGY- April 2000 subcapsular haematoma, four of which measured less than 1 cm in diameter. Due to this high incidence of small peripheral carcinomas, radical nephrec- tomy with meticulous histological examination of the resected specimen is the recommended treatment. How- ever, pre-operative angiography is considered warranted to exclude vas- cular disease which may affect the contralateral kidney and prompt a more conservative approach. Conclusion The diagnosis of spontaneous sub- capsular haematoma of the kidney is best made with CT, showing a sub- capsular mass compressing the renal parenchyma and often extending into the pararenal space. Treatment is usu- ally radical nephrectomy due to the high incidence of small peripheral carcinomas. Pre-operative angiogra- phy, although unreliable in the exclu- sion of small tumours is indicated to exclude other vascular causes which may prompt a more conservative ap- proach. References 1. Kendall RA, Senay BA, Coli ME, Spontaneous subcapsular renal haematoma: diagnosis and management, Journal of Urology 1988, 139: 246-250. 2. Pollack HM, Popky GL. Roentgenographic manifestations of spontaneous renal haemorrhage: Radiology 1974,110:1.