Comparison of cystatin C-based estimated glomerular filtration rate with measured glomerular filtration rate in a pediatric cohort of patients with chronic kidney disease.

BACKGROUND: It is essential to have an accurate assessment of the renal function of patients with chronic kidney disease to monitor, treat, and predict further development of the condition. Measurement of renal function in terms of glomerular filtration rate (GFR) requires either urine or blood sampling, but especially in children, more simple methods of measurement are preferable. The main objective of this study was to examine if the estimated GFR (eGFR) calculated with different cystatin-C-based equations was comparable to the GFR measured by a radiotracer (mGFR) in pediatric patients. METHODS: In this retrospective study, 28 pediatric patients contributed with 73 pairs of measurements collected within 5 years. Bland-Altman Limits of Agreement were used to evaluate the performance and accuracy of two different cystatin-C-based estimates, the CKiDCrea-CysC and the CKiDU25 respectively, compared to an mGFR based on plasma clearance of technetium-99m-diethylenetriaminepentaacetic acid or chromium-51-ethylenediaminetetraacetic acid. RESULTS: Using the CKiDCrea-CysC equation, 58.9% of the datasets were within P10 and 87.7% were within P30. The mean difference was 4.8 mL/min/1.73m2 (standard deviation: 8.5 mL/min/1.73m2) and tended to overestimate GFR and thereby overrate the kidney function within the entire GFR range. Using the CKiDU25 equation, 53.4% were within P10 and 93.2% within P30. The mean difference was -2.9 mL/min/1.73m2 (standard deviation: 8.4 mL/min/1.73m2), but the difference varied with the GFR value. CONCLUSIONS: A cystatin-C-based eGFR provides a viable substitute for monitoring renal function in pediatric patients with chronic kidney disease. However, it has a lower accuracy than mGFR and can therefore not replace mGFR in clinical use.

Quantitative 3D scintigraphy shows increased muscular uptake of pyrophosphate in idiopathic inflammatory myopathy.

BACKGROUND: Nuclear imaging is increasingly being used in the diagnostic work-up of idiopathic inflammatory myopathy (IIM). Increased muscular uptake of technetium-99m-pyrophosphate (99mTc-PYP) has hitherto been assessed qualitatively by planar scintigraphy. We set out to perform quantitative tomographic scintigraphy in IIM. RESULTS: Ninety IIM patients and 48 control subjects underwent 99mTc-PYP single-photon emission computed tomography (SPECT)/CT of the upper and lower body. Scans were evaluated visually by an intensity score (1-4) and quantitatively by the mean standardized uptake value (SUVmean) in thigh muscles after semi-automated segmentation of these. Furthermore, a SUVmean gradient down along the thighs was determined by linear regression of the slice-by-slice activity. Interobserver analyses were performed on qualitative evaluations. Compared to controls, patients more often had a high intensity score (p < 0.0001), but interobserver analyses revealed only moderate agreement. The thigh muscular 99mTc-PYP activity (SUVmean) was 60% higher in patients than in controls, p < 0.0001, albeit with a wide range. There was an activity gradient down the thigh muscle, the proximal tracer uptake being highest, and this gradient was steeper in patients than in controls; the activity decreased by 0.00024 and 0.00010 SUVmean mm-1, respectively, along the thighs. CONCLUSIONS: The muscular uptake of 99mTc-PYP was significantly higher in patients than in healthy controls by qualitative and quantitative assessment. The tracer uptake was higher in the proximal than in the distal part of the thigh muscle, and SUVmean gradients differed between groups. Hence, tomographic nuclear imaging allowing for quantification of the 99mTc-PYP uptake might contribute to the diagnosis of IIM, and SPECT/CT of the lower body might suffice.

Outcome of revascularisation in stable coronary artery disease without ischaemia: a Danish registry-based follow-up study.

OBJECTIVES: In stable coronary artery disease (CAD), coronary revascularisation may reduce mortality of patients with a certain amount of left ventricular myocardial ischaemia. However, revascularisation does not always follow the guidance suggested by ischaemia testing. We compared outcomes in patients without ischaemia who had either revascularisation or medical treatment. DESIGN AND POPULATION: Based on registries, 1327 consecutive patients with normal myocardial perfusion scintigraphy (MPS) and 278 with fixed perfusion defects were followed for a median of 6.1 years. Most patients received medical therapy alone (Med), but 26 (2%) with a normal MPS and 15 (5%) with fixed perfusion defects underwent revascularisation (Revasc). OUTCOME MEASURES: Incidence rates of all-cause death (ACD) and rates of cardiac death/myocardial infarction (CD/MI). RESULTS: With a normal MPS, the ACD rate was 6.2%/year in the Revasc group versus 1.9%/year in the Med group (p=0.01); the CD/MI rates were 6.9%/year and 0.6%/year, respectively (p<0.00001). Results persisted after adjustment for predictors of revascularisation, in particular angina score, and in comparisons of matched Revasc and Med patients. With fixed defects, the ACD rate was 9.1%/year in the Revasc group and 6.7%/year in the Med group (p=0.44); the CD/MI rate was 5.0%/year versus 4.2%/year, respectively (p=0.69). If adjusted for angiographic variables or analysed in matched subsets, differences remained insignificant. CONCLUSIONS: With normal MPS, revascularisation conferred a higher risk, even after adjustment for predictors of revascularisation. With fixed defects, the Revascversus Med difference was close to equipoise. Hence, in patients with stable CAD without ischaemia, we could not find evidence to justify exceptional revascularisation.

Raynaud's Phenomenon in a Slap Bass Player: A Case Report.

OBJECTIVE: Secondary Raynaud's phenomenon is a frequent condition related to occupational exposure to local vibration but has not been described in musicians. This study aims to describe cold-induced blanching of the right second and (in particular) third digits in a 67-year-old double bass player following decades of cumulative repetitive blunt trauma to the fingers from slapping the strings. METHODS: A physical examination was undertaken and systolic blood pressure measured before and after cold provocation. RESULTS: At 10 deg C the brachial systolic blood pressure was 156 mm Hg while blood pressure was immeasurable at the finger level, corresponding to a finger/brachial index of 0% of the second and third fingers. CONCLUSION: This is the first reported case of objectively verified, playing-related Raynaud's phenomenon in a musician.

[Diagnosis and treatment of symptomatic hydronephrosis in pregnancy]. / Diagnose og behandling af symptomgivende hydronefrose i graviditeten.

Hydronephrosis in pregnancy is common in the second and third trimester. Only a few cases are symptomatic, caused by a ureteric stone or by the pregnancy itself. The clinical dilemma is when to treat and when not to treat. We propose a multidisciplinary management based on renal ultrasonography to verify hydronephrosis and renography to diagnose obstructive hydronephrosis. Obstruction with a high intra-renal pressure must be treated to avoid kidney dysfunction. Patients with pyonephrosis need immediate treatment.

Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies.

OBJECTIVES: Knowledge of cardiac involvement in idiopathic inflammatory myopathies (IIM) is limited, especially in the early stage of disease. The objective of the present study was to perform a controlled evaluation of cardiac abnormalities in newly diagnosed, untreated patients with idiopathic inflammatory myopathies (IIM) by means of non-invasive techniques. METHODS: Fourteen patients with IIM (8 polymyositis, 4 dermatomyositis, 2 cancer-associated dermatomyositis) and 14 gender- and age- matched healthy control subjects were investigated. Participant assessments included a cardiac questionnaire, cardiac troponin-I (TnI), electrocardiogram (standard 12-lead and 48-h Holter monitoring), echocardiography with tissue Doppler measures, cardiac magnetic resonance (CMR) imaging with T2 mapping and semi-quantitative (99m)technetium pyrophosphate ((99m)Tc-PYP) scintigraphy. RESULTS: Dyspnoea was present in 8 (57%) of the patients compared to none of the controls (p<0.01). Median levels of TnI in patients and controls were 20 ng/L and 6 ng/L, respectively (p=0.06). QTc intervals were prolonged in the patient group (p=0.01). Two patients had systolic dysfunction, and one diastolic dysfunction. The myocardial (99m)Tc-PYP uptake and CMR results differed between patients and controls, albeit not with statistical significance. Overall, cardiac abnormalities were demonstrated in 9 (64%) of the patients versus 2 (14%) of the controls (p=0.02). CONCLUSIONS: Cardiac abnormalities assessed by TnI, ECG or imaging modalities were significantly more common in newly diagnosed, treatment naïve patients with IIM compared to healthy control subjects. These abnormalities, although subclinical, may indicate that myocardial involvement is common in patients and calls for larger controlled studies and further investigations of the prognostic implications of this finding.

Quantitative myocardial perfusion by O-15-water PET: individualized vs. standardized vascular territories.

AIMS: Reporting of quantitative myocardial blood flow (MBF) is typically performed in standard coronary territories. However, coronary anatomy and myocardial vascular territories vary among individuals, and a coronary artery may erroneously be deemed stenosed or not if territorial demarcation is incorrect. So far, the diagnostic consequences of calculating individually vs. standardly assessed MBF values have not been reported. We examined whether individual reassignment of vascular territories would improve the diagnostic accuracy of MBF with regard to the detection of significant coronary artery disease (CAD). METHODS AND RESULTS: Forty-four patients with suspected CAD were included prospectively and underwent coronary CT-angiography and quantitative MBF assessment with O-15-water PET followed by invasive, quantitative coronary angiography, which served as reference. MBF was calculated in the vascular territories during adenosine stress according to a standardized 17-segment American Heart Association model and an individualized model, using CT-angiography to adjust the coronary territories to their feeding vessels. Individually defined territories deviated from standard territories in 52% of patients. However, MBF in the three coronary territories defined by standard and individualized models did not differ significantly, except in one patient, in whom the MBF of an individualized coronary territory deviated sufficiently as to change the test from a false positive to a true negative result in this particular territory. CONCLUSION: Disparity between standardized and individualized vascular territories was present in half of the patients, but had little clinical impact. Still, caution should be taken not always to rely on standard territories, as this may at times cause misinterpretation.

Scintigraphic Small Intestinal Transit Time and Defaecography in Patients with J-Pouch.

Objective methods for examination of pouch function are warranted for a better understanding of the functional result and treatment of dysfunction. The objective of this study was to evaluate the results of scintigraphic intestinal transit time and defaecography compared to the results of pouch function, mucosal condition and a questionnaire on quality of life (QoL). This cross-sectional study included 21 patients. Scintigraphic transit time and defaecography was determined with the use of Tc-99m. Pouch function was assessed by number of bowel movements, pouch volume, and continence. Pouch mucosal condition was evaluated by endoscopy and histology. Median transit time was 189 min (105-365). Median ejection fraction at defaecography (EF) was 49% (3-77) and 62% (17-98) after first and second defecation. Median pouch volume was 223 mL (100-360). A median daily stool frequency of nine (4-25) was reported and three (14%) patients suffered from daytime incontinence. No patients had symptomatic or endoscopic pouchitis; however, the histology showed unspecific inflammation in 19 (90%) patients. There was no correlation between transit time, evacuation fraction (EF) and pouch function in univariate analysis. However, we found a high body mass index (BMI) and a low bowel movement frequency to be associated with a longer transit time by multivariate analysis. Scintigraphic determination of transit time and defaecography are feasible methods in patients with ileal pouch anal anastomosis, but the clinical relevance is yet doubtful.

(111)Indium-transferrin for localization and quantification of gastrointestinal protein loss.

OBJECTIVE: To evaluate the indium-111 ((111)In)-transferrin method as a means of localization and quantification of gastrointestinal protein loss. METHODS: Fourteen patients and 15 healthy subjects underwent an (111)In-transferrin study consisting of abdominal scintigraphy, whole-body counting measurement and determination of plasma activity of (111)In during the course of 5 days. Two of the patients went through a subsequent chromium-51-trichloride test with analysis of radioactivity in faeces in order to compare the results of the two methods. RESULTS: The patients had a mean +/-SEM whole-body loss of (111)In of 10.9+/-2.9% for 96 h, while the healthy controls lost 1.8+/-1.3% (p=0.0045). The decay in plasma activity followed biexponential kinetics. The characteristic plasma transit time was 5.0+/-1.0 h in patients and 12.1+/-1.5 h in controls (p=0.0007). Scintigraphically, patients had obvious abdominal foci of activity, while the control subjects showed diffuse activity. Anatomic localization of the leaking spot seemed more uncertain. By comparison with the (51)CrCl(3) test, the loss of radio-labelled protein appeared to be in the same order of magnitude. CONCLUSIONS: Quantification of gastrointestinal protein loss can be done without collecting faeces. Normal subjects have a loss of a few per cent, making the (111)In-transferrin method comparable with the former standard using (51)CrCl(3). Plasma measurements of (111)In are not predictive of the magnitude of the loss. Scintigraphic localization of the site of the loss needs to be optimized, for instance by serial imaging or image fusion with an anatomical modality.

[Protein-losing enteropathy--a new alternative of diagnosing and monitoring]. / Proteintabende enteropati--ny mulighed for diagnostik og behandlingskontrol.

Protein-losing gastroenteropathy (PE) is characterised by excessive loss of protein into the gastrointestinal tract. This condition associates not only with gastrointestinal disorders, but also with heart diseases, collagenoses, and several other generalized disorders. The symptoms are multiform and not necessarily abdominal. The treatment may be causal or symptomatic, and quite frequently it is possible to reduce the protein loss. The pathogenesis is considered multifactorial, but our knowledge of PE, including prevalence and clinical significance, is sparse, partly due to lack of appropriate examination procedures. Previous techniques were cumbersome and hampered by shortcomings. With 111In-transferrin, quantification and scintigraphic localization of the protein loss are obtained in one process and faeces collection is no longer needed. The method is promising, but further evaluation is necessary before it is brought into common clinical use.