Usefulness of Nonenhanced Computed Tomography for Diagnosing Urolithiasis without Pyuria in the Emergency Department.

We compared the clinical utility of nonenhanced computed tomography (NECT) and intravenous urography (IVU) in patients with classic symptoms of renal colic without evidence of a urine infection. This was a retrospective analysis of IVU and NECT performed in adult patients with suspected renal colic at an emergency department between January 2005 and December 2013. The records of all patients in NECT and IVU groups were reviewed, and the patients were categorized according to the cause of their symptoms. A total of 2218 patients were enrolled. Of these patients, 1525 (68.8%) underwent IVU and 693 (31.2%) underwent NECT. The patients in NECT group were older (45.48 ± 14.96 versus 42.37 ± 13.68 years, p < 0.001), had less gross hematuria (7.6 versus 2.9%, p < 0.001), and were admitted more often (18.6 versus 12.0%, p < 0.001) than the patients in IVU group. Urinary stones were detected in 1413 (63.7%) patients. NECT had a higher detection rate of urolithiasis than IVP (74.0 versus 59.0%, p < 0.001). No significant difference was observed in the incidence of urinary stones greater than 4mm between groups from the radiologic findings (p = 0.79) or the full medical record review (p = 0.87).

Prevalence and clinical importance of alternative causes of symptoms using a renal colic computed tomography protocol in patients with flank or back pain and absence of pyuria.

OBJECTIVES: The study was undertaken to determine the prevalence and clinical importance of alternative causes of symptoms discovered in patients undergoing flank pain protocol (FPP) computed tomography (CT) scans in patients with classic symptoms of kidney stone (flank pain, back pain, or both) without evidence of urine infection. METHODS: This was a retrospective observational analysis of all adult patients undergoing FPP CT scans at two emergency departments (EDs) between April 2005 and November 2010. All CTs (N = 5,383) were reviewed and categorized as "no cause of symptoms seen on CT," "ureteral stone as cause of symptoms," or "non-kidney stone cause of symptoms." Non-kidney stone scans were further categorized as "acutely important," "follow-up recommended," or "unimportant cause," based on a priori diagnostic classifications. All nonstone causes of pain and a random subset of subjects (n = 1,843; 34%) underwent full record review blinded to CT categorization to determine demographics, whether flank and/or back pain was present, and whether there was objective evidence of pyuria. RESULTS: Of all FPP CT scans during the study period, a ureteral stone was found to cause symptoms in 47.7% of CTs, with no cause of symptoms found in 43.3% of CTs. A non-kidney stone diagnosis was found in 9.0% of all CTs, with 6.1% being categorized as "acutely important," 2.2% as "follow-up recommended," and 0.65% with symptoms from an "unimportant cause." In the randomly selected subset undergoing full record review, categorizations were similar, with 49.0% of CTs showing kidney stone as cause of pain and 9.0% a non-kidney stone cause (5.9% "acutely important"). When subjects with evidence of urine infection or without flank or back pain were excluded, ureteral stone was identified as the cause of pain in 54.9% of CTs, while non-kidney stone cause of symptoms was found in 5.4% of scans and acutely important alternate causes in 2.8% of scans. CONCLUSIONS: While a non-kidney stone cause for a patient's symptoms are found in nearly 10% of CTs done using a FPP, acutely important findings occur in less than 3% of scans done in patients with flank or back pain and absence of pyuria.

Acute focal bacterial nephritis in 25 children.

Acute focal bacterial nephritis (AFBN), formerly known as lobar nephronia, is a rare form of interstitial bacterial nephritis. Most often described in adults with diabetes, there is only limited knowledge of AFBN in children. Ultrasound shows circular hypoechogenic, hypoperfused parenchyma lesions, which may be misdiagnosed as a renal abscess or tumor. From 1984 to 2005, AFBN was diagnosed in 30 children at the University Hospital Münster and the General Hospital Celle, Germany. Data of 25 cases (14 girls, 11 boys) were available for retrospective evaluation. Twenty-five children with AFBN, mean age 4.5 years (range: 0.25-17.5 years), were followed up on average 4.2 years (range: 0.5-11 years). All children were admitted to hospital due to fever and rapid deterioration of clinical condition, initially suspected of having meningitis (four patients), urinary tract infections (five patients), renal tumor (three patients), pneumonia (two patients), appendicitis (one patient), or with only unspecific symptoms (ten patients). AFBN was diagnosed by ultrasound on average 3 days (range: 1-10 days) after onset of symptoms. Pyuria was found in 18/25 children, bacteriuria in 20/25 children, and hematuria in one patient. Blood cultures were negative in all but one patient. Urinary tract abnormalities were found in 12 children, including vesicoureteral reflux (8), megaureter (1), urethral valves (1), unilateral renal hypoplasia (1), and one patient with megacystis, megaureter, caudal dystopic left kidney combined with hypoplasia and dysplasia of the right kidney. High-resolution ultrasound showed AFBN lesions to have resolved completely within 12 weeks after onset of intravenous antibiotic therapy in 20/25 children. Renal parenchymal cysts remained in three cases and focal scarring in two. Blood pressure and renal function was normal in 24/25 cases. AFBN should be suspected in children with fever and rapid deterioration of clinical condition. Residual lesions such as cysts or scarring of renal parenchyma could remain.

Multiphasic helical CT diagnosis of early medullary and papillary necrosis.

PURPOSE: The feasibility of identifying early manifestations of renal papillary necrosis (RPN) and medullary necrosis (RMN) on multiphasic helical CT, leading to prompt treatment for the causative conditions, and its impact on reducing the incidence of late-stage RML and RPN, was investigated. PATIENTS AND METHODS: Sixty-eight patients (35 male, 33 female) aged 19 to 88 years were examined by multiphasic helical CT for complaints of microscopic hematuria (N=49), macroscopic hematuria (N=2), bacteriuria (N=45), pyuria (N=10), fever (N=15), and flank pain (N=27). Preenhancement, arterial corticomedullary, parenchymal, and excretory phase scans generated 1.25 to 7-mm-thick slices. Follow-up CTs were performed at 1 month (N=62) and 3 months (N=58). RESULTS: While the attenuation coefficients of areas suspect for RMN and RPN were similar on preenhancement CT, they differed substantially on the arterial corticomedullary phase (lesions 55 HU mean; normal medulla 120 HU mean) and parenchymal phase (lesions 58 HU mean, normal medulla 210 HU mean). Investigation for predisposing conditions identified diabetes in 18 patients, upper urinary-tract infections in 48, sickle-cell disease or trait in 17, urinary obstruction in 7, and cirrhosis of the liver in 1. On follow-up examinations, enhancement had normalized in 26 compromised areas of 14 patients at 1 month, and 47 areas (23 patients) at 3 months, remained stationary in 28 patients at 1 month and 9 at 3 months, and progressed in 20 at 1 and 26 at 3 months (P<0.001; Fisher's exact test). Patients (N=35) treated for underlying conditions causing ischemia showed reperfusion in 12 cases at 1 month and 20 at 3 months, while of the untreated patients (N=10), none showed reperfusion, and all lesions increased in size. CONCLUSIONS: Multiphasic helical CT is recommended for identification of RMN and RPN at a stage when effective treatment of underlying causative conditions can arrest or reverse the process of devascularization and prevent loss of medullary tissue.

Medical imaging of renal diseases-suggested indication for different modalities.

The diagnostic work-up of the urologic patient must be tailored to the presenting symptom complex, carefully selecting from the many modilities available, those most likely to establish the diagnosis and extent of the suspected lesions. Intravenous urography is the most rewarding initial procedure for many presenting symptoms, including suspected masses, pyuria, hematuria, and flank pain. Nuclear imaging is particularly effective in differentiating renal lobulations from true masses, in demonstrating parenchymal scarring in chronic pyelonephritis when the IVP is equivocal, and in assessing the decrease in perfusion and function in obstructive nephropathy when the IVP is indeterminate. It is the preferred procedure for acute renal infarction and acute tubular necrosis and has a greater sensitivity of detection for renal trauma than the IVP. Gallium-67 renal imaging appear helpful in the detection of occult pyelonephritis or interstitial nephritis. However, it cannot differentiate focal acute pyelonephritis from abscess or abscess from neoplasm. Ultrasoneography is the initial procedure of choice in the differentiation of cystic from solid renal masses and in anuria or oliguria. When a kidney fails to visualize by IVP or nuclear imaging, it can confirm or rule out obstruction. In upper tract infections, it may demonstrate renal or perirenal abscess. Although retrograde pyelography is performed less frequently in recent years, it remains extremely useful in confirming and relieving obstructive uropathy and in delineating tumors of the collecting system. Computed tomography effectively demonstrates hydronephrosis, renal abscess, tumors, and cysts and retroperitoneal involvement. More experience is needed to judge the efficiency of "dynamic" CT for the quantification of renal function. Renal angiography remains invaluable as a secondary procedure (as opposed to initial screening) in renal trauma, vascular anomalies, and in renal tumors to delineate the anatomy of the arterial supply and possible renal vein involvement.

[Vaginal reflux during miction-cystourethrography in girls (author's transl)]. / Der vaginale Reflux whrend der Miktionszystourethrographie bei Mädchen.

The cases of 57 girls with reflux of radioopaque iodin solution into the vagina during mictioncystourethrography are reported. In 52.6% (30 cases) no signs of anomalies of the urinary tract or of pyelonephritis were found. For this group of 30 girls pyuria (leucocyturia) was typical (in 86.6%). In contrast, a urinarty-tract infection was found only in a few cases (16.6%). The authors discuss the clinical importance of vaginal reflux and its role in the pathogenesis of urinary-tract infections.

Pelviureteric obstruction in childhood.

Pelviureteric junction obstruction is a common cause of intra-abdominal mass in childhood. The diagnosis is usually apparent when the characteristic signs of obstruction are seen at intravenous urography. A voiding cystourethrogram should be performed to exclude vesicoureteral reflux as the underlying condition. Obstruction may be further assessed by a diuretic load or by pressure-flow studies.