Grey-Scale Ultrasound in the Imaging of Urinary Tract Disease

Grey-scale ultrasound defines smaller renal lesions that had previously been appreciated and is able to define associated lesions of the liver such as metastases and cysts. The appropriate technique to delineate the normal anatomy of the kidney is described. Ultrasound plays a central role in the identification and characterization of renal mass lesions thus leading to appropriate further work up. In renal transplant evaluation ultrasound is useful as a complementary modality to other imaging studies permitting the recognition of pelvic fluid collections, rejection, and hydronephrosis. Specific findings are present in renal abscess, perirenal abscess, and in several of the renal cystic diseases. Adrenal lesions can be identified and clarified. In the lower urinary tract, ultrasound can identify bladder and prostatic tumors.Ultrasound provides a rapid, safe and non-invasive modality which is complementary to other imaging techniques in the diagnosis of urinary tract disease.     

Ultrasonography compared with intravenous urography in the investigation of adults with haematuria.

OBJECTIVE--To compare ultrasonography with intravenous urography in the investigation of adults with haematuria. DESIGN--Prospective study entailing the examination of all patients with both investigations concurrently. The investigations were performed independently on routine lists by different duty radiologists. Each was aware of the details of the request form but not of the findings of the other investigation. SETTING--Radiology department of a teaching hospital. PATIENTS--155 Consecutive adult patients (aged 18-93) referred from general practitioners and hospital outpatient clinics with a history of haematuria. FOLLOW UP--When results of both examinations proved normal no clinical or radiological follow up was sought. All abnormal findings of either investigation were correlated with results of subsequent imaging studies or operative findings. RESULTS--81 Patients (52%) had normal findings on urography and ultrasonography. Overall, the findings of ultrasonography concurred with those of urography in 144 cases (93%). Among the discrepant findings of the two investigations ultrasonography missed two ureteric calculi; one was in a non-dilated ureter, and in the other case ultrasonography detected the secondary ureteric dilatation. Ultrasound examination alone detected four bladder tumours not visible on urography with sizes ranging from 5 to 21 mm, representing one fifth of the 20 cystoscopically proved bladder tumours detected in the series. Ultrasonography detected all the 22 neoplastic lesions discovered in the study (20 bladder, two renal). Ultrasonography clarified the nature of renal masses evident in three urograms (simple cysts). CONCLUSIONS--Ultrasonography is a safe and accurate method of investigating the urinary tract in adults with haematuria. When combined with a single plain abdominal radiograph it proved to be superior to urography as the primary imaging study in this series. Ultrasonography should certainly be preferred to urography if cystoscopy is not planned. No urothelial tumours of the upper urinary tract were found in the series, reflecting their rarity. For those patients in whom ultrasonography and plain radiography have shown no abnormality and in whom cystoscopic appearances are normal urography would be advisable to exclude urothelial tumours of the upper urinary tract.     

Local and diffuse bacterial adherence on uroepithelial cells

The concept of local and diffuse adherence has been described for enteropathogenicEscherichia coli. In the present study, similar findings are reported for bacterial adherence to uroepithelial cells from patients with acute urinary tract infection and following incubation in an in vitro adherence assay. A population of cells were seen with few or no bacteria attached; others had localized areas of adherent organisms, while some cells were heavily colonized in a diffuse manner. These patterns were noted in vitro for anEscherichia coli strain and aLactobacillus casei strain, which possess different adhesins, therefore indicating that the adherence patterns were probably due to epithelial cell differences. The light microscopy and scanning electron microscopy observations illustrate that bacterial adherence to uroepithelial cells occurs in localized and diffuse distributions. The results indicate that there are differences in uroepithelial cell receptivity for bacterial attachment. The availability of cells receptive to uropathogens and indigenous flora, such as lactobacilli, is probably one of several factors that influence the pathogenesis of urinary tract infections.     

Immunohistochemical characterization of cloned lamb nephropathy.

Kidneys from lambs derived by nuclear transfer are frequently abnormal and are characterized by an enlarged pelvis and narrow medulla, consistent with lower urinary tract obstruction and development of variable hydronephrosis. The precise pathogenesis of this entity is unknown. Immunohistochemical staining for intermediate filaments was used to further characterize the lesions seen in this condition and was compared with age-matched control tissue. Major findings were upregulation of cytokeratin on damaged tubules, desmin and vimentin in undifferentiated mesenchyme, and smooth muscle actin in mesenchyme and on smooth muscle "collars" around dilated tubules. In addition, some cases showed reexpression of vimentin and desmin on proximal tubular epithelial cells. Taken together, these findings provide a valuable database for tracking the expression of intermediate filaments throughout renal development in sheep and have further characterized the nature of the response to injury by the developing kidney, a response that is characterized by proliferation of mesenchyme and both reexpression and upregulation of intermediate filaments within renal cells. In addition, the study has confirmed that the changes in cloned lamb nephropathy are established by day 85 of development.     

Ultrasonography compared with intravenous urography in investigation of urinary tract infection in adults.

OBJECTIVE--To compare ultrasonography with intravenous urography for investigating adults with proved urinary tract infection. DESIGN--Prospective study of patients presenting consecutively for radiological investigation of urinary tract infection between October 1988 and December 1989. Both investigations were performed concurrently and performed independently on routine lists by different duty radiologists, each of whom knew the details on the request form but not the findings of the other investigation. SETTING--Radiology department of a teaching hospital. PATIENTS--158 Consecutive adults (89 women, 69 men; mean age 49.7 (range 18-83)) referred from general practitioners and hospital outpatient clinics with a history of proved urinary tract infection. INTERVENTIONS--Urography and ultrasonography performed concurrently. When both examinations gave normal findings no clinical or radiological follow up was sought. All abnormal findings detected with either investigation were confirmed by subsequent imaging studies or by operative procedures. MAIN OUTCOME MEASURE--Accuracy of detection of abnormalities of urinary system by ultrasonography compared with urography. RESULTS--113 Patients (72%) had normal urographic and ultrasonic findings. Overall, ultrasonography concurred with the findings of urography in 149 (94%) patients, and when a single abdominal radiograph was included in the procedure, in 152 (96%). Ultrasonography missed only one important diagnosis, that of mild papillary necrosis in normal sized kidneys in a diabetic patient. It detected one early bladder tumour not visible on urography and was able to clarify the nature of renal masses (simple cysts) evident on three urograms. CONCLUSION--Ultrasonography provides a safe and accurate method of imaging the urinary tract in adults with infection. Combined with a plain abdominal radiograph, it should replace urography as the initial imaging investigation in these patients. Major savings would result from adopting this policy, and the risks to patients from ionising radiation and intravenous contrast media would be appreciably reduced.     

Prevalence of spina bifida occulta in patients with functional disorders of the lower urinary tract and its relation to urodynamic and neurophysiological measurements.

OBJECTIVE--To determine the relation between neurophysiological abnormalities and the radiological detection of spina bifida occulta in patients with dysfunction of the lower urinary tract. DESIGN--Blind assessment and subsequent decoding of mixed batch of abdominal radiographs from patients with and without urological symptoms for evidence of spina bifida occulta and comparison of results with those of previous control series. SETTING--Review study among tertiary referrals to an incontinence clinic of a city hospital. PATIENTS--One hundred and thirty eight adults with proved urodynamic abnormalities in whom neurophysiological measurements were available. INTERVENTIONS--None. END POINT--Correlation of neurophysiological abnormalities in lower urinary tract dysfunction with presence and type of spina bifida occulta and level of opening of posterior sacral arcs. MEASUREMENTS AND MAIN RESULTS--On decoding radiographs those from patients without urological symptoms showed a similar prevalence of spina bifida occulta to that in the control series (631/2707 controls; 23%). By contrast, patients with urological symptoms had a significantly increased prevalence of spina bifida occulta at S1 and S2 and a higher level of opening of posterior sacral arcs. The increased prevalence of the bony defect was particularly striking in men with urgency and instability and in women with stress incontinence. No significant correlation was found between any particular neurophysiological abnormality and the presence of spina bifida. CONCLUSIONS--In patients with dysfunction of the lower urinary tract neurophysiological abnormalities may be associated with congenital dysraphic lesions in the lower lumbar spine and sacrum. There appears to be no direct causal relation between the radiological and neurophysiological abnormalities but the findings suggest a common aetiological factor.     

Use of cytomorphometry and cytology in the diagnosis of transitional-cell carcinoma of the upper urinary tract

Because of the rise in incidence of upper urinary tract tumors, there is a need for a simple and reliable method for diagnosing these tumors, especially in people in a "high-risk" group. This retrospective study showed the usefulness of cytology and cytomorphometry in making the diagnosis of transitional-cell carcinoma of the upper urinary tract. The study also emphasized that the methods of collection and processing are of the utmost importance: the cytologic evaluation of ureteral catheterized urine specimens gave 100% accuracy as compared with a 40% false-negative rate in the cytologic diagnosis of voided urine specimens. A higher accuracy of urinary cytology for the diagnosis of upper urinary tract lesions clearly requires selective catheterization of the ureter. Objective cytomorphologic grading of the urinary cytology specimens was shown to compare favorably with histologic grading. Cytomorphologic grading not only can offer important information in determining the prognosis and in planning treatment but can also assist in quality control of other diagnostic methods and can help to resolve apparent diagnostic discrepancies.     

Urinary tract infections in children. An update.

Urinary tract infection is a common and frequently recurring condition in children. The susceptibility of the host, the presence of urinary tract abnormalities, and the virulence of the urinary pathogens are of primary importance in the development of the infection. Renal parenchymal scarring, hypertension, and renal insufficiency are well-established complications of the infection in children. To reduce the risk of renal damage, diagnosis and treatment must be prompt. The diagnosis demands radiologic evaluation of the urinary tract in all boys, all children younger than 5 years, all patients with voiding dysfunction, and school-aged girls with recurrent infection to identify those patients with vesicoureteral reflux, obstruction, or other urinary tract abnormalities. Both voiding cystourethrography and renal ultrasonography are the initial examinations to use to determine the next appropriate study. Children with vesicoureteral reflux or with recurrent urinary tract infections should receive prophylactic antibiotic therapy and should be observed closely to prevent renal scarring.     

Colic as the sole symptom of urinary tract infection in infants.

Urinary tract infection was diagnosed in four infants whose sole symptom was persistent recurrent colic. There were no other clinical abnormalities. Three had abnormal radiologic findings in the urinary tract and one subsequently required nephrectomy. In the two others, radiologic findings were normal after 6 months and 1 year, respectively.     

Asymptomatic Significant Bacteriuria in the Non-pregnant Woman: I. Description of a Population

The clinical, laboratory, and radiological findings in a group of 107 non-pregnant bacteriuric women and 88 controls have been compared. A previous history of urinary tract infection was more commonly obtained from the bacteriuric women. The means of the diastolic blood pressures, serum ureas, and erythrocyte sedimentation rates were significantly higher in the bacteriuric group, and acquired renal abnormalities were demonstrated in 18% of the bacteriuric women as compared with 4% of the controls. It is concluded that screening for asymptomatic bacteriuria in the adult non-pregnant female population in many instances fails to detect urinary tract infection at an early and reversible stage.     

Slit-scan cytofluorometry. Basis for automated prescreening of urinary tract cytology.

A study was undertaken to assess the applicability of the slit-scan technique to automated prescreening of urinary tract cytology. Cells from voided and catheterized urines were stained with acridine orange and measured on a static cell slit-scan cytofluorometer. Analysis of data from the specimens indicates that nuclear fluorescence alone appears adequate for recognition of abnormal specimens. Remaining problems in the automation of urinary tract cytology prescreening are discussed.     

Value of antenatal diagnosis of abnormalities of the urinary tract.

OBJECTIVE--To assess the value of antenatal diagnosis of abnormalities of the urinary tract on ultrasonography. DESIGN--Retrospective study. SETTING--Two obstetric units in Glasgow. SUBJECTS--62 Fetuses in which renal abnormalities were diagnosed on antenatal ultrasonography. INTERVENTIONS--Six fetuses had their bladders aspirated to determine renal function. Fifteen pregnancies were terminated on the basis of the findings on antenatal ultrasonography, and if possible necropsy was performed on the fetuses. In babies who were born alive the final diagnosis was made by postnatal ultrasonography, intravenous urography, radionuclide scanning, cystography, and, in those who died in the early neonatal period, necropsy. Neonates who were referred with a known obstructed kidney had nephrostomy or pyeloplasty. END POINT--Assessment of the value of antenatal diagnosis of renal abnormalities on ultrasonography for babies who had no clinical evidence of disease postnatally. MAIN RESULTS--Eighteen fetuses did not survive birth; the antenatal diagnosis was accurate in all 18. Of the 44 babies born alive, five had normal urinary tracts, in two of whom antenatal ultrasonography had probably indicated a false positive diagnosis. Fourteen babies died during the early neonatal period. Twenty five babies with renal abnormalities were followed up; the antenatal diagnosis was inaccurate for 10 of them, the commonest misdiagnosis being hydronephrosis for multicystic kidney and vice versa, and there was one false positive diagnosis. The initial clinical findings in 14 babies would have led to the early detection of a urological abnormality. In the 30 babies with no clinical evidence of disease the antenatal diagnosis was of definite value in eight, probable value in 15, and marginal value in seven. Overall, an accurate antenatal diagnosis was made in 46 of the 62 cases (74%); in 12 cases renal disease was detected but its specific nature was not determined; and in four cases the diagnosis was misleading. CONCLUSIONS--The overall value of antenatal diagnosis is that it indicates early termination of fetuses with fatal renal disease, prepares parents and medical staff for the likelihood of serious neonatal problems, and shows abnormalities of the urinary tract that may not be detected postnatally.     

Schistosoma haematobium: the pathology of experimental infection

The pathologic changes in experimental animals infected with Schistosoma haematobium are reviewed and compared to the pathology in infected humans. The clinically important lesions in persons infected with S. haematobium are generally confined to the urogenital system. In experimental animals, functionally important lesions of the urogenital system are the exception but do occur in a significant proportion of infected primates. The acute lesions of the urinary tract in primates are similar to those in infected persons. Chronic lesions characterized by the extensive submucosal accumulation of calcified eggs are common in infected humans but uncommon in S. haematobium-infected animals.     

Clinical importance of significant asimptomatic bacteriuria in newborns and infants during early postnatal period

The aim of the study was to detect newborns at risk for developing renal impairment, and to point out the importance of significant asimptomatic bacteriuria in perinatal period and early infancy. Severe urinary tract anomalies are very often accompanied only by asimptomatic bacteriuria in perinatal period. Three urinalysis ware done after delivery. 212 newborns with significant asimptomatic bacteriuria underwent ultrasound examination, and were followed up to three months. Those with normal findings and with passing bacteriuria in the first 2 months were excluded. Group of 52 newborns underwent radioisotope examination. Frequency of urinary tract anomalies in newborns was 34.6%. Increased risk for renal impairment had children with urinary tract anomalies in close family, urinary tract infection or bacteriuria, EPH gestosis and prepartal symptoms of febrile infection in mother, children with IUGR, strangulated umbilical cord, prolonged jaundice and attacks of peripheral cyanosis in perinatal period.     

Frequency of lethal congenital malformations. Experience supported by 600 autopsies

Data analysis of 600 neonatal necropsies performed in our Center from 1978 to 1984, has shown that in 200 cases one or more lethal malformations were observed: the most frequent concerned the central nervous system (33 cases), the urinary tract system (28 cases) and the cardiovascular system (26 cases). A genetic determinism was considered in 127 cases (63,5%). Usually a genetic counselling follows neonatal death in our Center: necropsy findings are then most useful: the authors advocate the interest of a close collaboration between pathologists and geneticists.     

Differential immunocytochemical staining patterns of uroplakin observed on neoplastic and nonneoplastic tissue fragments obtained from upper urinary tract brush specimens

OBJECTIVE: To discern any differences in the distribution of uroplakin expression on neoplastic and nonneoplastic upper urinary tract lesions. STUDY DESIGN: Thirty-seven representative 95% ethanol-fixed direct smears of brush specimens, which were subsequently diagnosed histologically as 10 reactive and 27 transitional cell carcinomas (TCCs), were stained with polyclonal uroplakin antibodies utilizing the avidin-biotin-peroxidase method. In order to ascertain any differences in diagnostic accuracy between conventional cytomorphology and uroplakin immunocytochemical staining, the results were compared to the original final cytologic diagnoses for all 37 cases. RESULTS: The linear staining pattern on the luminal surface of umbrella cells was the dominant pattern expressed on tissue fragments from all 10 reactive lesions. Tissue fragments from low grade TCC demonstrated a weaker and less continuous superficial membrane staining pattern along with a variably intense, diffuse, membranous staining pattern throughout the tumor cell groups. This staining pattern was seen in all 17 (sensitivity = 100%) histologically confirmed low grade TCCs, of which only 13 of the 17 (sensitivity = 76.5%) were diagnosed as TCC on the original final cytology report. Tissue fragments from 10 high grade TCCs lacked the superficial linear staining pattern seen in reactive cell groups. Instead, all 10 high grade TCCs displayed a strong diffuse membrane staining pattern in all the cells in the fragment and also demonstrated microluminal structures within the tumor cell groups. CONCLUSION: The distinctive patterns of uroplakin antigen expression observed in nonneoplastic and neoplastic upper urinary tract lesions in the present study can greatly enhance the accuracy of diagnostic interpretation of upper urinary tract lesions in conventional cytologic specimens.     

Serodiagnosis and the immunological aspects of Proteus infection. IV. Serum antibody level and the pathomorphological and bacteriological indices in experimental mixed and monoinfections of the urinary tract

In developing the serodiagnosis of the Proteus infection of the urinary tract experimental hematogenic Proteus or Proteus-Escherichia pyelonephritis was reproduced. In this infection the time course, level and avidity of serum antibodies correlated with the isolation of the causative agents from urine samples used as seed material and with histological changes in the kidneys. The serological tests revealed high titres of H-antibodies and the presence of O-antibodies, while in cases of bacteriuria not accompanied by kidney lesions only H-antibodies in low titers were detected. The results obtained in the study of immune shifts can be used for etiological diagnosis and more exact localization of the pathological process in the urinary system.     

Community behavior and amyloid-associated phenotypes among a panel of uropathogenic E. coli

Uropathogenic Escherichia coli (UPEC) are the major causative agents of urinary tract infection and engage in a coordinated genetic and molecular cascade to colonize the urinary tract. Disrupting the assembly and/or function of virulence factors and bacterial biofilms has emerged as an attractive target for the development of new therapeutic strategies to prevent and treat urinary tract infection, particularly in the era of increasing antibiotic resistance among human pathogens. UPEC vary widely in their genetic and molecular phenotypes and more data are needed to understand the features that distinguish isolates as more or less virulent and as more robust biofilm formers or poor biofilm formers. Curli are extracellular functional amyloid fibers produced by E. coli that contribute to pathogenesis and influence the host response during urinary tract infection (UTI). We have examined the production of curli and curli-associated phenotypes including biofilm formation among a specific panel of human clinical UPEC that has been studied extensively in the mouse model of UTI. Motility, curli production, and curli-associated biofilm formation attached to plastic were the most prevalent behaviors, shared by most clinical isolates. We discuss these results in the context on the previously reported behavior and phenotypes of these isolates in the murine cystitis model in vivo.     

Vesicoureteral reflux and other urinary tract malformations in mice compound heterozygous for Pax2 and Emx2

Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of chronic kidney disease in children. This disease group includes a spectrum of urinary tract defects including vesicoureteral reflux, duplex kidneys and other developmental defects that can be found alone or in combination. To identify new regulators of CAKUT, we tested the genetic cooperativity between several key regulators of urogenital system development in mice. We found a high incidence of urinary tract anomalies in Pax2;Emx2 compound heterozygous mice that are not found in single heterozygous mice. Pax2^+/−;Emx2^+/− mice harbor duplex systems associated with urinary tract obstruction, bifid ureter and a high penetrance of vesicoureteral reflux. Remarkably, most compound heterozygous mice refluxed at low intravesical pressure. Early analysis of Pax2^+/−;Emx2^+/− embryos point to ureter budding defects as the primary cause of urinary tract anomalies. We additionally establish Pax2 as a direct regulator of Emx2 expression in the Wolffian duct. Together, these results identify a haploinsufficient genetic combination resulting in CAKUT-like phenotype, including a high sensitivity to vesicoureteral reflux. As both genes are located on human chromosome 10q, which is lost in a proportion of VUR patients, these findings may help understand VUR and CAKUT in humans.