Pathophysiology of bone disease in chronic kidney disease: from basics to renal osteodystrophy and osteoporosis

Chronic kidney disease (CKD) is a highly prevalent disease that has become a public health problem. Progression of CKD is associated with serious complications, including the systemic CKD-mineral and bone disorder (CKD-MBD). Laboratory, bone and vascular abnormalities define this condition, and all have been independently related to cardiovascular disease and high mortality rates. The "old" cross-talk between kidney and bone (classically known as "renal osteodystrophies") has been recently expanded to the cardiovascular system, emphasizing the importance of the bone component of CKD-MBD. Moreover, a recently recognized higher susceptibility of patients with CKD to falls and bone fractures led to important paradigm changes in the new CKD-MBD guidelines. Evaluation of bone mineral density and the diagnosis of "osteoporosis" emerges in nephrology as a new possibility "if results will impact clinical decisions". Obviously, it is still reasonable to perform a bone biopsy if knowledge of the type of renal osteodystrophy will be clinically useful (low versus high turnover-bone disease). However, it is now considered that the inability to perform a bone biopsy may not justify withholding antiresorptive therapies to patients with high risk of fracture. This view adds to the effects of parathyroid hormone in CKD patients and the classical treatment of secondary hyperparathyroidism. The availability of new antiosteoporotic treatments bring the opportunity to come back to the basics, and the knowledge of new pathophysiological pathways [OPG/RANKL (LGR4); Wnt-ß-catenin pathway], also affected in CKD, offers great opportunities to further unravel the complex physiopathology of CKD-MBD and to improve outcomes.

The “FIFTY SHADOWS” of the RALES Trial: Lessons about the Potential Risk of Dietary Potassium Supplementation in Patients with Chronic Kidney Disease

Hyperkalaemia (HK) is one of the most common electrolyte disorders and a frequent reason for nephrological consultations. High serum potassium (K⁺) levels are associated with elevated morbidity and mortality, mainly due to life-threatening arrhythmias. In the majority of cases, HK is associated with chronic kidney disease (CKD), or with the use of renin–angiotensin–aldosterone system inhibitors (RAASis) and/or mineral corticoid antagonists (MRAs). These drugs represent the mainstays of treatment in CKD, HF, diabetes, hypertension, and even glomerular diseases, in consideration of their beneficial effect on hard outcomes related to cardiovascular events and CKD progression. However, experiences in relation to the Randomised Aldactone Evaluation Study (RALES) cast a long shadow that extends to the present day, since the increased risk for HK remains a major concern. In this article, we summarise the physiology of K⁺ homeostasis, and we review the effects of dietary K⁺ on blood pressure and cardiovascular risk in the general population and in patients with early CKD, who are often not aware of this disease. We conclude with a note of caution regarding the recent publication of the SSaSS trial and the use of salt substitutes, particularly in patients with a limited capacity to increase K⁺ secretion in response to an exogenous load, particularly in the context of “occult” CKD, HF, and in patients taking RAASis and/or MRAs.

C-C motif chemokine receptor 2 as a novel intermediate in the ovulatory cascade

Expression of immune function genes within follicle cells has been reported in ovaries from many species. Recent work from our laboratory showed a direct effect of the monocyte chemoattractant protein 1/C-C motif chemokine receptor 2 system within the feline cumulus oocyte complex, by increasing the mRNA levels of key genes involved in the ovulatory cascade in vitro. Studies were designed to evaluate if C-C motif chemokine receptor 2 acts as a novel mediator of the ovulatory cascade in vitro. Therefore, feline cumulus oocyte complexes were cultured in the presence or absence of a highly selective C-C motif chemokine receptor 2 antagonist together with known inducers of cumulus-oocyte expansion and/or oocyte maturation to assess mRNA expression of key genes related to periovulatory events in other species as well as oocyte maturation. Also, the effects of recombinant monocyte chemoattractant protein 1 on spontaneous or gonadotrophin-induced oocyte maturation were assessed. This is an in vitro system using isolated cumulus oocyte complexes from feline ovaries. The present study reveals the modulation of several key ovulatory genes by a highly selective C-C motif chemokine receptor 2 antagonist. However, this antagonist was not enough to block the oocyte maturation induced by gonadotropins or amphiregulin. Nonetheless, recombinant monocyte chemoattractant protein 1 had a significant effect on spontaneous oocyte maturation, increasing the percentage of metaphase II stage oocytes in comparison to the control. This is the first study in any species to establish C-C motif chemokine receptor 2 as a mediator of some actions of the mid-cycle gonadotrophin surge.

MO968ROUTINE BIOMARKERS FOR THE SEVERITY OF COVID-19 PNEUMONIA MAY PRESENT DIFFERENTLY IN KIDNEY TRANSPLANT RECIPIENTS

Background and Aims

The treatment of coronavirus disease (COVID-19) is based on the patient’s clinical status and levels of inflammatory biomarkers. The comparative activity of these biomarkers in KT patients with COVID-19 pneumonia from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and non-SARS-CoV-2 aetiologies is unknown. The aim of this study was to compare the clinical presentation and inflammatory parameters at admission of KT patients with COVID-19 pneumonia and those with non-COVID-19 pneumonia over the same period.

Method

Biomarkers were measured and compared between KT patients with COVID-19 pneumonia (n=42) and non-COVID-19 pneumonia (n=18) from March to November 2020.

Results

Both groups showed comparable demographics. The COVID-19 KT patients had fewer neutrophils (4,650 [2,925-9,498] vs. 9,100 [7,170-11,150],p=0.01) than the non-COVID group, although there was no significant difference in the lymphocyte count. Non-COVID-19 pneumonia was associated with a higher d-dimer (962 [427-1,448] vs. 1,704 [868-2,481],p=0.09) and IL-6 (37 [23-10] vs 254 [53-602],p=0.006) levels. The ferritin level was higher in the COVID-19 group (908 [496-1,377] vs. 340 [264-785],p=0.008).

Conclusion

COVID-19 pneumonia in KT recipients shows a different presentation of inflammatory biomarkers than other non-COVID pneumonias. It could be usefully to identify KT patients with COVID-19.More detailed studies are necessary to understand the presentation of biomarkers in KT with COVID-19.

Cadmium exposure during pregnancy reduces birth weight and increases maternal and foetal glucocorticoids

Cadmium exposure induces low birth weight through unknown mechanisms. Since low birth weight is associated to foetal exposure to high glucocorticoids (GC) concentrations, we hypothesized that low birth weight induced by prenatal exposure to Cd(2+) is, at least in part, mediated by higher foetal exposure to GC, specifically corticosterone, the main active GC in rodents. Pregnant rats were exposed to different dose of CdCl(2) administered in drinking water during the whole pregnancy period. At term, corticosterone was measured by enzyme immunoassay in maternal and foetal blood and in placental tissues. Cadmium was determined in placentas, maternal tissues (liver and kidney) and foetuses by inductively coupled plasma-mass spectrometry (ICP-MS). Placental 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) activity and expression were determined by a radiometric conversion assay and quantitative RT-PCR respectively. Results demonstrated that 50 ppm of Cd(2+), which was accumulated in different maternal tissues but not in the foetus, reduced pup birth weights and increased plasma corticosterone concentrations, both in mother and foetus. Placental 11beta-HSD2 activity and expression did not change by the treatment. We conclude that 50 ppm of Cd(2+) administered during pregnancy, increase foetal corticosterone concentrations due, probably, to alterations of the regulatory mechanisms of placental barrier to GC causing a mild but significant reduced birth weight.

Effects of post-emergent herbicides on Trichoderma harzianum , a potential biocontrol agent against Sclerotinia sclerotiorum in soybean cropping

Trichoderma harzianum is a potential biocontrol agent against Sclerotinia sclerotiorum in soybean. Information is needed on the compatibility of this biocontrol agent and the post-emergent herbicides used in soybean cropping.Haloxyfop R Methyl (EC 10.4%), Glyphosate (SL 48%), Imazamox (WG 70%) and Imazethapyr (SL 10%) were evaluated for their effects on the mycelial growth of T. harzianum on in vitro agar plates. Glyphosate (2000 ppm), Imazethapyr (500 and 250 ppm) and Haloxyfop R Methyl (1000, 500 and 100 ppm) reduced the mycelial growth of T. harzianum . Imazamox had no effect at any concentration.Subsequently, all the herbicides were assessed for their effect on soil populations of T. harzianum . Greenhouse assays conducted with non-sterile soil inoculated with T. harzianum and a specific herbicide were sampled before pesticide application and after 30 days. The number of colony forming units per gram of soil (c.f.u./g of soil) was evaluated with a soil dilution technique using Trichoderma selective medium (TSM). No detrimental effect was revealed.

[Effectivity versus toxicity of minoxidil as antiproliferative agent for lens epithelial cells. In vitro study]

PURPOSE

To evaluate the inhibitory effect of minoxidil on cultured proliferating lens epithelial cells (LECs) versus cytotoxic effect over corneal endothelial cells in culture, because minimum side effects over anterior chamber structures and particularly on corneal endothelium are required for successful therapy and prevention of posterior capsular opacification (PCO).

METHODS

New Zealand Rabbit LECs and corneal endothelium were cultured in DMEM at 35 degrees C in 5% CO2 in multiwells during 7 days. Both types of cells were exposed to minoxidil (1, 2 and 4 mM) for 1 and 24 hours. Control group and balanced salt solution group were included. After seven days multiwells were processed for light microscopy study. Morphometric study of cellular population of LECs and corneal endothelium cells were done using a computed planimetry system.

RESULTS

Dose-dependent effect on LECs proliferation was noted and non-confluent colonies of cells were observed on all treated groups. Morphologic changes in normal appearance of corneal endothelial cells after 1 hour of minoxidil treatment was observed and intracellular alterations were confirmed even with the lowest dose exposure.

CONCLUSIONS

Although effectiveness of minoxidil suppressing in vitro LECs proliferation could be suggest as a useful therapeutic agent to prevent PCO, however the inhibitory effect of different concentrations on corneal endothelial cells conditioned its possible use on ocular surgery.

Utility of serial urinary tumor markers to individualize intervals between cystoscopies in the monitoring of patients with bladder carcinoma

BACKGROUND

Cross-section studies have shown the diagnostic characteristics of certain urinary tumor markers for the detection of bladder carcinoma. However, the role of serial urinary tumor markers in the monitoring of patients with bladder carcinoma in daily clinical surveillance has not been completely defined yet.

METHODS

The study comprised 1185 urine samples belonging to 232 patients with a previous bladder carcinoma: 106 patients under follow-up (Group 1) and 126 bladder carcinoma patients receiving intravesic instillations (Group 2). Patients were monitored with urinary tumor markers during a one-year follow-up period. Urine samples were collected before cystoscopies and in the intercystoscopic periods for patients in Group 1 and before intravesic instillations for patients Group 2. Urinary bladder carcinoma antigen (UBC), CYFRA 21-1 and nuclear matrix proteins (NMP22) were measured by immunoassays.

RESULTS

Monitoring of the disease with urinary tumor markers could detect recurrence sooner than scheduled cystoscopies in 27 patients (87%) for UBC, 27 patients (87%) for CYFRA 21-1, and 26 patients (84%) for NMP22 out of 31 Group 1 patients who recurred; and in 16 patients (67%) for UBC, 17 patients (71%) for cytokeratin fragments (CYFRA) 21-1, and 13 patients (54%) for NMP22 out of 24 Group 2 patients who recurred. The most relevant finding was that persistence of negative urinary markers during follow-up was largely indicative of disease free status in 65 of 75 (87%) patients of Group 1 and 31 of 102 (30%) cases of Group 2. Although false positive results were present, they were mainly associated with sporadic urinary tract infections in 10 of 75 (13%) cases of Group 1 and in 36 of 102 (35%) patients of Group 2; and with urine samples collected in the first two months at the beginning of intravesic therapy in 35 of 102 patients (34%) in Group 2.

CONCLUSIONS

Monitoring of bladder carcinoma patients with serial urinary tumor markers could anticipate detection of recurrence. Persistent negative results might postpone and reduce the number of cystoscopies. Once the limitations leading to false positive results are controlled by urinalysis and by starting sample collection when basal levels are reached in patients with intravesic therapy, urinary tumor markers might eventually individualize the intervals between cystoscopies in the surveillance of patients with bladder carcinoma.

Diagnostic performance of the urinary bladder carcinoma antigen ELISA test and multiparametric DNA/cytokeratin flow cytometry in urine voided samples from patients with bladder carcinoma

BACKGROUND

The objective of the current study was to comparatively analyze the sensitivity and specificity of flow cytometric DNA/cytokeratin 8/18 measurements and the urinary bladder carcinoma antigen (UBC) enzyme linked immunoabsorbent assay (ELISA) test for the detection of bladder carcinoma in voided urine samples.

METHODS

Eighty-one fresh urine voided samples, preserved frozen for a maximum period of 3 months, belonging to patients with an active bladder carcinoma (n = 37), patients who were free of disease as confirmed by cystoscopy (n = 19), patients receiving intravesical therapy (n = 17), and individuals with other benign and malignant conditions (n = 8), were collected. Flow cytometry measurements of thawed samples were based on the detection of cytokeratin (CK) 8+ and CK18+ cells using the 3F3 and 6D7 monoclonal antibodies alone or in combination with the measurement of cell DNA contents, after propidium iodide staining. Urinary bladder carcinoma antigen test was measured by ELISA.

RESULTS

Patients were grouped according to the presence (n = 44) or absence (n = 29) of bladder carcinoma as confirmed by cystoscopy, and taking cutoffs of 9.7 microg/L for UBC-ELISA, 75% for the percentage of 3F3 (+) and 6D7 (+) cells, and 10.6% for the proportion of hyperdiplod cells that suggested a specificity of 83%, the individual sensitivity obtained for each parameter was 77%, 5%, 9%, and 77%, respectively. The presence of DNA aneuploid populations showed a relatively low sensitivity (36%) although it was the most specific parameter (93%). Combining UBC antigen test with the proportion of cells showing DNA content higher than 2n increased to 89% the sensitivity of the UBC antigen alone. However, false-positive results for both techniques were found in individuals with urologic diseases other than bladder carcinoma and in patients receiving intravesical therapy.

CONCLUSIONS

The authors' results suggest that the combined use of the UBC antigen test and DNA/cytokeratin flow cytometry double stainings for the analysis of freshly obtained urine voided samples, cryopreserved to assure cellular integrity, is of great clinical utility for the detection of tumor recurrence in patients with bladder carcinoma.

Serial urinary IL-2, IL-6, IL-8, TNFalpha, UBC, CYFRA 21-1 and NMP22 during follow-up of patients with bladder cancer receiving intravesical BCG

BACKGROUND

We evaluated the potential role of serial preinstillation levels of several interleukins, TNFalpha and urinary tumor markers to monitor patients with bladder cancer receiving intravesical BCG.

PATIENTS AND METHODS

121 urine samples were collected from: patients with bladder cancer treated with BCG (group 1); patients with bladder cancer receiving other intravesical treatment (group 2) and patients with urinary tract infections (group 3). Cytokines [IL-2, IL6 and [L8] and TNFalpha and urinary tumor markers [UBC, CYFRA 21-1 and NMP22] were measured by immunoassays.

RESULTS

In 3 out of 15 BCG non-responders that recurred over the period of the study, no cytokine peak for IL-2, IL-6 or TNFa were detected. Urinary tumor markers increased in 2 out of 3 of these patients earlier than scheduled cystoscopies. Cytokine measurement was heterogeneous among 12 out of 15 BCG-responding patients: there were low levels of IL-6 and TNFalpha and peaks of IL-2 and IL-8 in 10 out of 12 and 4 out of 12 patients, respectively. During responding patients' follow-up we observed false-positive results in 7 out of 65 urine samples for UBC, 8 out of 65 for CYFRA 21-1 and 20 out of 65 for NMP22. Urinary tract infections were the main factor associated with non-specific elevations of IL-6 and IL-8 and urinary tumor markers in all groups of patients.

CONCLUSION

Although larger series are required to confirn our preliminary observations, our data argue for a potential predictive role for IL-2 of favourable response to BCG therapy. Monitoring BCG with urinary tumor markers could early detect recurrence in non-responding patients.

Comparative predictive values of urinary cytology, urinary bladder cancer antigen, CYFRA 21-1 and NMP22 for evaluating symptomatic patients at risk for bladder cancer

PURPOSE

We study the potential diagnostic use of urinary bladder cancer antigen, CYFRA 21-1 and NMP22*; for evaluating symptomatic patients who present with microscopic hematuria and are at risk for bladder cancer.

MATERIALS AND METHODS

Urinary tumor markers were determined in 187 samples from 112 patients symptomatic of bladder cancer (group 1), and 75 with benign and other urological conditions (group 2). Immunoassays were used to measure the 3 selected biomarkers. Sensitivity and specificity were established by previously defined cut points. Biomarker results were reported as corrected and uncorrected for urinary creatinine. Urinalysis was performed in all samples.

RESULTS

Positive and negative predictive values were 85.5%, 80.5% and 81.1%, and 80.8%, 79.2% and 76.5% for urinary bladder cancer antigen, CYFRA 21-1 and NMP22, with the cutoffs 9.7 microg./l., 5.4 microg./l and 10.0 units per ml., respectively. These predictives values were 85.2% and 72.5%, respectively, for urinary cytology. The combination of biomarkers decreased the positive predictive values to 72.3% to 78.6% and increased negative predictive values to 84.2% to 86.1%. Urinary tract infection, inflammation and malignancy associated with other genitourinary organs were the primary cause for false-positive test results in the 3 assays evaluated.

CONCLUSIONS

With a single biomarker, around 80% of the positive results would have correctly identified symptomatic patients for cystoscopy. Of the negative results 75% would have correctly reduced the number of cystoscopies. Sensitivity and negative predictive values could be improved with the combination of biomarkers but with a loss of specificity and positive predictive values. Urinary tract inflammation and other genitourinary malignancies might contribute to the reduction in specificity of these tests.

Estimation of the hydrophobic effect in an antigen-antibody protein-protein interface

Antigen-antibody complexes provide useful models for analyzing the thermodynamics of protein-protein association reactions. We have employed site-directed mutagenesis, X-ray crystallography, and isothermal titration calorimetry to investigate the role of hydrophobic interactions in stabilizing the complex between the Fv fragment of the anti-hen egg white lysozyme (HEL) antibody D1.3 and HEL. Crystal structures of six FvD1.3-HEL mutant complexes in which an interface tryptophan residue (V(L)W92) has been replaced by residues with smaller side chains (alanine, serine, valine, aspartate, histidine, and phenylalanine) were determined to resolutions between 1.75 and 2.00 A. In the wild-type complex, V(L)W92 occupies a large hydrophobic pocket on the surface of HEL and constitutes an energetic "hot spot" for antigen binding. The losses in apolar buried surface area in the mutant complexes, relative to wild-type, range from 25 (V(L)F92) to 115 A(2) (V(L)A92), with no significant shifts in the positions of protein atoms at the mutation site for any of the complexes except V(L)A92, where there is a peptide flip. The affinities of the mutant Fv fragments for HEL are 10-100-fold lower than that of the original antibody. Formation of all six mutant complexes is marked by a decrease in binding enthalpy that exceeds the decrease in binding free energy, such that the loss in enthalpy is partly offset by a compensating gain in entropy. No correlation was observed between decreases in apolar, polar, or aggregate (sum of the apolar and polar) buried surface area in the V(L)92 mutant series and changes in the enthalpy of formation. Conversely, there exist linear correlations between losses of apolar buried surface and decreases in binding free energy (R(2) = 0.937) as well as increases in the solvent portion of the entropy of binding (R(2) = 0.909). The correlation between binding free energy and apolar buried surface area corresponds to 21 cal mol(-1) A(-2) (1 cal = 4.185 J) for the effective hydrophobicity at the V(L)92 mutation site. Furthermore, the slope of the line defined by the correlation between changes in binding free energy and solvent entropy approaches unity, demonstrating that the exclusion of solvent from the binding interface is the predominant energetic factor in the formation of this protein complex. Our estimate of the hydrophobic contribution to binding at site V(L)92 in the D1.3-HEL interface is consistent with values for the hydrophobic effect derived from classical hydrocarbon solubility models. We also show how residue V(L)W92 can contribute significantly less to stabilization when buried in a more polar pocket, illustrating the dependence of the hydrophobic effect on local environment at different sites in a protein-protein interface.

The complex dynamic network of microtubule and microfilament cytasters of the leech zygote

The organization of the cytoskeleton in the early first interphase zygote and its involvement in organelle redistribution were studied in the glossiphoniid leech Theromyzon trizonare by confocal and electron microscopy, immunofluorescence, and time-lapse video imaging after microinjection of labeled tubulin and/or actin and loading with a mitotracker. The cytoskeleton consists of an inner or endoplasmic and an outer or ectoplasmic domain. The inner domain consists of a monaster whose fibers retract from the zygote periphery by the end of the early first interphase. The outer domain is built upon a network of microtubules and microfilaments cytasters. Short pulses of microinjected labeled actin or tubulin and Taxol treatment demonstrate that cytasters are centers of microtubule and microfilament nucleation. Immunostaining with anti-centrophilin, anti-BX-63, and anti-AH-6 indicates that the network of cytasters includes centrosomal antigens. Cytasters move in an orderly fashion at speeds of 0.5-2 micrometer/min, in an energy-dependent process retarded and finally blocked by the ATP analogue AMP-PNP and high concentrations of Taxol. Colliding cytasters fuse and form larger cytoskeletal nucleation centers. The leech zygote is a highly compartmentalized cell whose cytasters function as articulated components of a very dynamic cytoskeletal system engaged in bulk transportation of organelles during ooplasmic segregation.

Evaluation of two new urinary tumor markers: bladder tumor fibronectin and cytokeratin 18 for the diagnosis of bladder cancer

Our objectives were to evaluate the diagnostic value of two new urinary tumor markers, cytokeratin 18 (CK18) and bladder tumor fibronectin (BTF), for the detection and monitoring of bladder cancer. The study comprised 931 urine samples belonging to 402 subjects: 112 individuals under suspicion for a primary bladder tumor (group 1); 104 bladder cancer patients under scheduled follow-up (group 2); 109 bladder cancer patients receiving intravesical instillations (group 3); 45 patients with other urological diseases (group 4); and 32 healthy subjects (group 5). Voided urine samples were collected before cystoscopies, between them and before intravesical instillations. CK18 and BTF tests were measured by chemiluminescent immunoassays. Optimal receiver operating characteristic cutoffs of 7.4 microg/L for CK18 and 52.8 microg/liter for BTF rendered overall sensitivities of 66.2% for CK18 and 80.0% for BTF at specificities of 88.4 and 74.7%, respectively. Urinary cytology provided a sensitivity of 29.2% at a specificity of 99.1%. Sensitivities were 80.8, 74.2, and 82.3% for BTF and 71.1, 77.4, and 64.7% for CK18 for groups 1 to 3, respectively. False positive rates were higher for BTF in all groups of patients. Elevated urinary tumor markers during the monitoring of patients with bladder cancer could detect recurrence sooner than scheduled cystoscopies. Persistence of negative markers was greatly indicative of free of disease status in follow-up. CK18 and BTF in urine may eventually prove to be of benefit for specific patients with bladder carcinoma given its higher sensitivity compared with cytology. In selected patients, namely those with persistent negative urinary CK18 and BTF, the number of cystoscopies could be reduced.

Urinary tissue polypeptide-specific antigen for the diagnosis of bladder cancer

OBJECTIVES

To evaluate the diagnostic characteristics of the urinary measurement of cytokeratin tissue polypeptide-specific antigen (TPS) for the detection of bladder cancer.

METHODS

Three hundred thirty-five individuals in five groups were studied: group 1, subjects with microhematuria under suspicion for primary bladder cancer; group 2, patients being followed up with scheduled cystoscopic examinations; group 3, patients in follow-up receiving chemotherapy instillations; group 4, patients with other urologic diseases; and group 5, healthy subjects. Urine samples belonging to subjects from groups 1, 2, and 3 were collected immediately before cystoscopy. Additionally, patients from groups 2 and 3 were monitored with urinary TPS for a minimum period between two cystoscopies. TPS was measured by an enzyme immunosorbent assay.

RESULTS

Receiver operating characteristic analysis gave a sensitivity of 64% and a specificity of 84% at a threshold value of 279 U/L. The positive and negative predictive value was 66% and 82%, respectively; accuracy was 77%. TPS could discriminate the presence of bladder tumor sooner than the scheduled cystoscopies in 9 of 19 follow-up patients with recurrence. False-positive results during follow-up were found in 112 urine samples, one third of which were associated with urinary tract infections. TPS did not appear to be specific for bladder cancer, with elevated results in 45% of patients from group 4, which might lead to clinical misinterpretation of urinary TPS results.

CONCLUSIONS

Urinary TPS might provide additional information for the detection of bladder cancer as an adjunct to cystoscopy. Considering the false-positive rates, different urologic diseases should be ruled out before making clinical decisions on the basis of elevated urinary TPS results.

[Cytokeratins (UBC and CYFRA 21-1) and nuclear matrix proteins (NMP22) as urine tumor markers in the diagnosis of bladder cancer]

BACKGROUND

The development of urinary tumor markers such as UBC, CYFRA 21-1 and NMP22 appeared to be non invasive alternative methods for the detection of bladder cancer. We compared the individual and combined sensitivity of the urinary tumor markers in the detection of bladder cancer, contrasting them with the conventional diagnostic procedures.

PATIENTS AND METHODS

237 voided urines from subjects under risk for bladder cancer were collected immediately before the endoscopic examinations: 44 patients under suspicion of a primary bladder tumor and 193 patients under follow-up of a previous bladder cancer were included. UBC and NMP22 were measured by enzyme-immunoabsorbent-assays and CYFRA 21-1 by an electro-chemiluminescense-immunoassay.

RESULTS

Taking the cutoffs of 9.7 micrograms/l for UBC, 5.4 ng/ml for CYFRA 21-1 and 10.0 U/ml for NMP22 sensitivities were 70%, 69% and 67% for UBC, CYFRA 21-1 and NMP22 at specificities of 95%, 94% y 80%, respectively. All tumor markers showed higher sensitivities than urinary cytology (7%), microhematuria (62%) and gross hematuria (10%) at specificities of 99%, 78% and 99%, respectively. The combinations of NMP22 plus CYFRA 21-1 reached the highest sensitivity (79%), slightly lower than simultaneously measuring the three tumor markers (80%).

CONCLUSIONS

The sensitivities of the urinary markers UBC, CYFRA 21-1 and NMP22 appeared to be high enough so as to substitute urinary cytology. The diagnostic similarity between cytokeratins individually and in each type of patients might not recommend their simultaneous determination. The combined measurement of NMP22 and one cytokeratin marker (CYFRA 21-1 or UBC) appeared to be the most recommended.

Dynamic gadolinium-enhanced MR findings in infantile hepatic hemangioendothelioma

We report a case of a 2 1/2-year-old girl presenting with abdominal pain, fever, vomiting, and hepatomegaly. In spite of the unusual age at presentation, dynamic gadolinium-enhanced MR findings, which have not been previously illustrated, proved to be highly specific for the diagnosis of infantile hepatic hemangioendothelioma because of the characteristic enhancement pattern.

Rectal perflubron: new application in MRI of perirectal fistulae

PURPOSE

Our goal was to determine the efficacy of MRI with rectal administration of perflubron in the evaluation of perirectal and pelvic fistulae, with an emphasis on development of an improved method for fistula visualization.

METHOD

Fourteen pelvic and/or perirectal fistulae were evaluated in nine patients with MRI after the rectal administration of 200 ml of perflubron. Images were reviewed by two independent readers and evaluated for the presence or absence of fistulae. Qualitative assessment was also performed, rating the examinations for the ability to visualize the fistulae. Comparison was made with the clinical examination and/or operative findings, as well as available preperflubron imaging studies (CT = 10; fluoroscopy = 1; preperflubron MRI = 4).

RESULTS

MRI with rectal perflubron demonstrated all 14 fistulae (100%), while preperflubron imaging demonstrated only 7 of 14 (50%) fistulae (p < or = 0.008, Wilcoxon signed rank test). In addition, MRI with perflubron resulted in significantly improved qualitative visualization of fistulae (overall very good rating versus poor rating for preperflubron imaging, p < or = 0.006, Wilcoxon signed rank test).

CONCLUSION

MRI with rectal perflubron is a superior modality for imaging of fistulae, compared with conventional methods, since it allows a noninvasive means of demonstrating the presence of a fistula as well as offers improved qualitative assessment of fistulous disease.

Cystic masses of the spleen: radiologic-pathologic correlation

Many focal splenic lesions may appear to be cystic at cross-sectional imaging. In this article, the following types of cystic splenic masses are discussed: congenital (true cyst), inflammatory (abscesses, hydatid cyst), vascular (infarction, peliosis), posttraumatic (hematoma, false cyst), and neoplastic (hemangioma, lymphangioma, lymphoma, metastasis). The key findings at ultrasound, computed tomography, and magnetic resonance imaging can be correlated with underlying gross and microscopic pathologic findings. Although tissue sampling is still required in many cases to yield a definitive diagnosis, recognition and understanding of the spectrum of imaging and pathologic features of these lesions often help narrow the differential diagnosis.

[Adverse reactions to contrast media for intravenous use. A comparison between ionic and nonionic media]

The purpose of this study was to show that the nonionic contrast media of low osmolarity are better tolerated than ionic media of high osmolarity, which to date are most frequently used in the authors hospital. We found that adverse reaction occurred in 80% of the group in which nonionic contrast medium was used. The authors conclude that nonionic, low osmolarity contrast media significantly reduce the frequency of adverse reactions and increase their safe use.

[Duplex sonography in the diagnosis of deep venous thrombosis in the lower limbs]

Duplex ultrasonography (DUS) has shown high sensitivity and specificity in the diagnosis of proximal deep vein thrombosis (DVT). It is now considered the initial procedure of choice for the evaluation of this entity because of its advantages (low cost, non invasiveness, no need for contrast media, no ionizing radiation) and because of the possibility of making other diagnoses, v.g. Baker's cyst. With the development of color Doppler, this study has become easier and now includes the calf and iliac vessels. Nevertheless, it has not improved the sensitivity and specificity of DUS. Phlebography, until now the "golden standard", has become a "second choice" procedure for proximal DVT but it continues to be of value in the evaluation of calf veins, which are more difficult to evaluate with DUS, and other venous pathology.

[Adverse reactions to high osmolarity contrast media. A comparative-prospective study]

The purpose of this study was to verify and compare the different types of reactions to iodinated contrast media available at the Social Security Metropolitan Hospital Complex: Conray 60%, Vascoray and Uromiron. These are ionic, high osmolality compounds. The authors found that, in 400 patients not only the osmolality had an important role in the reactions observed, but that the intrinsic nature of the molecule of the contrast medium used was the determining factor.

[Solid and papillary epithelial neoplasm of the pancreas. Report of 2 cases]

Solid and papillary epithelial tumor of the pancreas occurs mainly in young women and its main characteristic is the appearance of an abdominal mass which progressively increases in size. The radiologic, surgical and pathological correlation shows that it is a tumor of low grade malignancy with a favorable prognosis, after therapy and according to the location of the tumor. The authors report the clinical history of the first two confirmed cases of this entity in Panama, which occurred in 1985 and 1992, respectively, in women less than 25 years of age.

[The sonographic diagnosis of hypertrophic stenosis of the pylorus]

The clinical records of 18 children were studied, between 15 and 60 days old. They were hospitalized due to vomiting and diagnosis of suspected pyloric hypertrophic stenosis (PHS). The sonography confirmed the diagnosis in 8 children, by the thickening of the muscular layer and enlargement of the pyloric canal. The surgery (pyloromyotomy) ratified the diagnosis in all 8 children. They all were in good health after being operated.

[The sonographic diagnosis of hypertrophic stenosis of the pylorus]

The clinical records of 18 children were studied, between 15 and 60 days old. They were hospitalized due to vomiting and diagnosis of suspected pyloric hypertrophic stenosis (PHS). The sonography confirmed the diagnosis in 8 children, by the thickening of the muscular layer and enlargement of the pyloric canal. The surgery (pyloromyotomy) ratified the diagnosis in all 8 children. They all were in good health after being operated.

A telephone survey to measure risk factor prevalence in communities across Canada

From 1985 to 1988, 10 Canadian community health units, in conjunction with Health and Welfare Canada, conducted a standardized telephone survey to assess the prevalence of health risk factors among persons aged 15 and over. Seatbelt use, hypertension awareness, physical activity, smoking, alcohol use, cancer screening status and sociodemographic variables were ascertained in each community. Although prevalence rates for most of the major risk factors varied significantly among the survey communities, little clustering of high or low risk levels was observed in any particular locale. Periodic administration of the risk factor survey in communities across Canada would provide a valuable data base for both public health planners and researchers.

[Know well in order to do well]

Health care professionals should have comprehensive training, especially in the humanitarian aspects of care. This is essential to enable them to correctly resolve ethical conflicts that arise in professional practice. Starting from this premise, the article discusses some representative situations nurses encounter daily in their contacts with patients. An examination is made of the ethical aspects of the following: ordinary nursing activities; standards with regard to hospital visits by family members; administration of analgesics; schedules for feeding, drug administration, and the like; clinical research; professional secrecy; free professional practice; and death with dignity.

[Adenocarcinoma in bladder exstrophy]

We present a case of vesical extrophy complicated by an adenocarcinoma in a 35-year old patient. It is this type of neoformation which most frequently affects the extrophic bladder and which, contrary to what has happened in most of the cases published, quickly presented bone and skin metastases.

[Statistics of urological infections in the hospital environment]

A review is made of the clinical histories of 1,821 patients admitted to our Department for treatment over a three-year-period and on the basis of the data compiled, the doctors have made a statistical study of urinary infections, by determining the type of germ, etiology of the process and level of sensitivity to the different antibiotics and chemiotherapeutic drugs and by analysing, at the same time, the inference between the different parameters considered. Of the results presented, they stress that the practical erradication of E. coli as an infecting agent in our medium, is significant, as well as the probable existence of an epidemiological cycle lasting for periods of twenty one months although this has still to be confirmed by means of longer chronological series.

[Advance in the immunologic study of urologic neoplasms]

The reduction of the levels of circulating T lymphocytes in urological neoplasias seems obvious. The existence of a link between the different, neoplastic, bladder and prostate processes, as well as the degree of malignancy, prognosis and therapeutic response has still to be established, according to the immunitary state of the patients. The constant developing and refining of the immunological technology will no doubt serve to resolve these problems.