The urine protein to creatinine ratio (P/C) as a predictor of 24-hour urine protein excretion in renal transplant patients

Podocyte number and glomerulosclerosis indices are associated with the response to therapy for primary focal segmental glomerulosclerosis

Corticosteroid therapy, often in combination with inhibition of the renin-angiotensin system, is first-line therapy for primary focal and segmental glomerulosclerosis (FSGS) with nephrotic-range proteinuria. However, the response to treatment is variable, and therefore new approaches to indicate the response to therapy are required. Podocyte depletion is a hallmark of early FSGS, and here we investigated whether podocyte number, density and/or size in diagnostic biopsies and/or the degree of glomerulosclerosis could indicate the clinical response to first-line therapy. In this retrospective single center cohort study, 19 participants (13 responders, 6 non-responders) were included. Biopsies obtained at diagnosis were prepared for analysis of podocyte number, density and size using design-based stereology. Renal function and proteinuria were assessed 6 months after therapy commenced. Responders and non-responders had similar levels of proteinuria at the time of biopsy and similar kidney function. Patients who did not respond to treatment at 6 months had a significantly higher percentage of glomeruli with global sclerosis than responders (p < 0.05) and glomerulosclerotic index (p < 0.05). Podocyte number per glomerulus in responders was 279 (203-507; median, IQR), 50% greater than that of non-responders (186, 118-310; p < 0.05). These findings suggest that primary FSGS patients with higher podocyte number per glomerulus and less advanced glomerulosclerosis are more likely to respond to first-line therapy at 6 months. A podocyte number less than approximately 216 per glomerulus, a GSI greater than 1 and percentage global sclerosis greater than approximately 20% are associated with a lack of response to therapy. Larger, prospective studies are warranted to confirm whether these parameters may help inform therapeutic decision making at the time of diagnosis of primary FSGS.

Rapamycin Treatment Alleviates Chronic GVHD-Induced Lupus Nephritis in Mice by Recovering IL-2 Production and Regulatory T Cells While Inhibiting Effector T Cells Activation

In this study, we test the therapeutic effects of rapamycin in a murine model of SLE-like experimental lupus nephritis induced by chronic graft-versus-host disease (cGVHD). Our results suggest that rapamycin treatment reduced autoantibody production, inhibited T lymphocyte and subsequent B cell activation, and reduced inflammatory cytokine and chemokine production, thereby protecting renal function and alleviating histological lupus nephritis by reducing the occurrence of albuminuria. To explore the potential mechanism of rapamycin's reduction of kidney damage in mice with lupus nephritis, a series of functional assays were conducted. As expected, rapamycin remarkably inhibited the lymphocytes' proliferation within the morbid mice. Interestingly, significantly increased proportions of peripheral CD4+FOXP3+ and CD4+CD25high T cells were observed in rapamycin-treated group animals, suggesting an up-regulation of regulatory T cells (Tregs) in the periphery by rapamycin treatment. Furthermore, consistent with the results regarding changes in mRNA abundance in kidney by real-time PCR analysis, intracellular cytokine staining demonstrated that rapamycin treatment remarkably diminished the secretion of Th1 and Th2 cytokines, including IFN-γ, IL-4 and IL-10, in splenocytes of the morbid mice. However, the production of IL-2 from splenocytes in rapamycin-treated mice was significantly higher than in the cells from control group animals. These findings suggest that rapamycin treatment might alleviate systemic lupus erythematosus (SLE)-like experimental lupus nephritis through the recovery of IL-2 production, which promotes the expansion of regulatory T cells while inhibiting effector T cell activation. Our studies demonstrated that, unlike other commonly used immunosuppressants, rapamycin does not appear to interfere with tolerance induction but permits the expansion and suppressive function of Tregs in vivo.

Influence of Persistent Inflammation in Follow-Up Biopsies After Antibody-Mediated Rejection in Kidney Transplantation

Background: Despite recent advances in immunosuppression treatment, antibody-mediated rejection (ABMR) remains the leading cause of kidney graft loss. Information about prognostic markers and the efficacy of treatment is scarce.

Methods: Retrospective study with kidney recipients diagnosed an active ABMR from January 1, 2004 to December 31, 2019 to explore the influence of persistent inflammation in follow-up biopsies on graft survival after ABMR treatment.

Results: About 116 patients were included. Active ABMR were treated with a combination of plasma exchange (PE), intravenous immunoglobulin (IVIg), rituximab, and steroids. At 6 months of treatment, 63 (54.3%) patients presented a stabilization or improvement in kidney-graft function. The effectiveness varied depending on the timepoint of the presentation between transplantation and rejection, which is lower for those with late ABMR (63 vs. 21% for early vs. late ABMR, respectively). Ninety patients (77%) underwent a control biopsy after ABMR treatment, from which 46 (51%) responded to the treatment. Microvascular inflammation (MVI) persisted in 64 (71%) biopsies, whereas tubulitis persisted in 17 (19%) biopsies. Death-censored graft survival at 1 year was significantly lower in patients with persistent MVI (86% vs. 95% without persistent MVI, P = 0.002), or with persistent tubulitis (44% vs. 66% without tubulitis, P = 0.02). In the Cox Regression analysis, the persistence of MVI [hazard ratio (HR), 4.50 (95%CI, 1.35–14.96), P = 0.01] and tubulitis [HR 2.88 95%CI (1.24–6.69), P = 0.01) in follow-up biopsies significantly increased the risk of graft failure.

Conclusion: Persistent inflammation in follow-up biopsies after ABMR treatment was associated with an increased risk of graft loss, even without meeting Banff rejection criteria.

Study Registration: Agencia Española de Medicamentos y Productos Sanitarios (AEMPS): 14566/RG 24161. Study code: UTRINM-2017-01.

Dynamic prediction of renal survival among deeply phenotyped kidney transplant recipients using artificial intelligence: an observational, international, multicohort study

BACKGROUND

Kidney allograft failure is a common cause of end-stage renal disease. We aimed to develop a dynamic artificial intelligence approach to enhance risk stratification for kidney transplant recipients by generating continuously refined predictions of survival using updates of clinical data.

METHODS

In this observational study, we used data from adult recipients of kidney transplants from 18 academic transplant centres in Europe, the USA, and South America, and a cohort of patients from six randomised controlled trials. The development cohort comprised patients from four centres in France, with all other patients included in external validation cohorts. To build deeply phenotyped cohorts of transplant recipients, the following data were collected in the development cohort: clinical, histological, immunological variables, and repeated measurements of estimated glomerular filtration rate (eGFR) and proteinuria (measured using the proteinuria to creatininuria ratio). To develop a dynamic prediction system based on these clinical assessments and repeated measurements, we used a Bayesian joint models-an artificial intelligence approach. The prediction performances of the model were assessed via discrimination, through calculation of the area under the receiver operator curve (AUC), and calibration. This study is registered with ClinicalTrials.gov, NCT04258891.

FINDINGS

13 608 patients were included (3774 in the development cohort and 9834 in the external validation cohorts) and contributed 89 328 patient-years of data, and 416 510 eGFR and proteinuria measurements. Bayesian joint models showed that recipient immunological profile, allograft interstitial fibrosis and tubular atrophy, allograft inflammation, and repeated measurements of eGFR and proteinuria were independent risk factors for allograft survival. The final model showed accurate calibration and very high discrimination in the development cohort (overall dynamic AUC 0·857 [95% CI 0·847-0·866]) with a persistent improvement in AUCs for each new repeated measurement (from 0·780 [0·768-0·794] to 0·926 [0·917-0·932]; p<0·0001). The predictive performance was confirmed in the external validation cohorts from Europe (overall AUC 0·845 [0·837-0·854]), the USA (overall AUC 0·820 [0·808-0·831]), South America (overall AUC 0·868 [0·856-0·880]), and the cohort of patients from randomised controlled trials (overall AUC 0·857 [0·840-0·875]).

INTERPRETATION

Because of its dynamic design, this model can be continuously updated and holds value as a bedside tool that could refine the prognostic judgements of clinicians in everyday practice, hence enhancing precision medicine in the transplant setting.

FUNDING

MSD Avenir, French National Institute for Health and Medical Research, and Bettencourt Schueller Foundation.

Single versus en bloc kidney transplant from donors less than or equal to 15 kg to pediatric recipients

With small kidneys, EBKTs could provide sufficient renal mass but could lead to inefficient use of resources, while SKTs could result in insufficient function due to small renal mass. We aimed to compare the outcomes of EBKT and SKT from small donors weighing ≤15 kg to pediatric recipients. We retrospectively reviewed all pediatric patients who met the inclusion criteria between January 1, 1984, and April 30, 2019, at a single institution. Of a total of 23 patients, 12 received EBKT and 11 received SKT. The median age of donors, weight of donors, and weight of recipients were comparable between the two groups. The median age of recipients and median weight of allografts were greater in the EBKT group than in the SKT group. The median follow-up was 53.9 months. There was no significant difference in eGFR, protein creatinine ratios at 1-year follow-up, and overall graft survival. The size of the kidney increased by approximately 13%-43% in the EBKT group and 40%-60% in the SKT group. This study demonstrated that kidneys from small donors weighing 5-15 kg could be split in pediatric recipients without compromising the outcome.

Trajectories of glomerular filtration rate and progression to end stage kidney disease after kidney transplantation

Although the gold standard of monitoring kidney transplant function relies on glomerular filtration rate (GFR), little is known about GFR trajectories after transplantation, their determinants, and their association with outcomes. To evaluate these parameters we examined kidney transplant recipients receiving care at 15 academic centers. Patients underwent prospective monitoring of estimated GFR (eGFR) measurements, with assessment of clinical, functional, histological and immunological parameters. Additional validation took place in seven randomized controlled trials that included a total of 14,132 patients with 403,497 eGFR measurements. After a median follow-up of 6.5 years, 1,688 patients developed end-stage kidney disease. Using unsupervised latent class mixed models, we identified eight distinct eGFR trajectories. Multinomial regression models identified seven significant determinants of eGFR trajectories including donor age, eGFR, proteinuria, and several significant histological features: graft scarring, graft interstitial inflammation and tubulitis, microcirculation inflammation, and circulating anti-HLA donor specific antibodies. The eGFR trajectories were associated with progression to end stage kidney disease. These trajectories, their determinants and respective associations with end stage kidney disease were similar across cohorts, as well as in diverse clinical scenarios, therapeutic eras and in the seven randomized control trials. Thus, our results provide the basis for a trajectory-based assessment of kidney transplant patients for risk stratification and monitoring.

Targeted Urine Metabolomics for Monitoring Renal Allograft Injury and Immunosuppression in Pediatric Patients

Despite new advancements in surgical tools and therapies, exposure to immunosuppressive drugs related to non-immune and immune injuries can cause slow deterioration and premature failure of organ transplants. Diagnosis of these injuries by non-invasive urine monitoring would be a significant clinical advancement for patient management, especially in pediatric cohorts. We investigated the metabolomic profiles of biopsy matched urine samples from 310 unique kidney transplant recipients using gas chromatography-mass spectrometry (GC-MS). Focused metabolite panels were identified that could detect biopsy confirmed acute rejection with 92.9% sensitivity and 96.3% specificity (11 metabolites) and could differentiate BK viral nephritis (BKVN) from acute rejection with 88.9% sensitivity and 94.8% specificity (4 metabolites). Overall, targeted metabolomic analyses of biopsy-matched urine samples enabled the generation of refined metabolite panels that non-invasively detect graft injury phenotypes with high confidence. These urine biomarkers can be rapidly assessed for non-invasive diagnosis of specific transplant injuries, opening the window for precision transplant medicine.

Diagnostic utility of protein to creatinine ratio (P/C ratio) in spot urine sample within routine clinical practice

The spot (random) urine protein to creatinine ratio (P/C ratio) is an alternative, fast and simple method of detecting and estimating the quantitative assessment of proteinuria. The aim of the work was to review the literature concerning the usefulness of spot urine P/C ratio evaluation in the diagnosis of proteinuria in the course of kidney disease, hypertension, gestational hypertension, preeclampsia, immunological diseases, diabetes mellitus, and multiple myeloma, and in the diagnosis of proteinuria in children. We searched the PubMed and Google Scholar databases using the following keywords: proteinuria, spot urine protein to creatinine ratio, spot urine P/C ratio, protein creatinine index, PCR (protein to creatinine ratio), P/C ratio and methods, Jaffe versus enzymatic creatinine methods, urine protein methods, spot urine protein to creatinine ratio versus ACR (albumin to creatinine ratio), proteinuria versus albuminuria, limitations of the P/C ratio. More weight was given to the articles published in the last 10-20 years. A spot urine P/C ratio >20 mg/mmol (0.2 mg/mg) is the most commonly reported cutoff value for detecting proteinuria, while a P/C ratio value >350 mg/mmol (3.5 mg/mg) confirms nephrotic proteinuria. The International Society for the Study of Hypertension in Pregnancy recommends a P/C ratio of 30 mg/mmol (0.3 mg/mg) for the classification of proteinuria in pregnant women at risk of preeclampsia. A high degree of correlation was observed between P/C ratio values and the protein concentration in 24-h urine collections. The spot urine P/C ratio is a quick and reliable test that can eliminate the need for a daily 24-h urine collection. However, in doubtful situations, it is still recommended to assess proteinuria in a 24-h urine collection. The literature review indicates the usefulness of the spot P/C ratio in various disease states; therefore, this test should be available in every laboratory. However, the challenge for the primary care physician is to know the limitations of the methods used to determine the protein and creatinine concentrations that are used to calculate the P/C ratio. Moreover, the P/C ratio cutoff used should be determined in individual laboratories because it depends on the patient population and the laboratory methodologies.

Rituximab, plasma exchange and immunoglobulins: an ineffective treatment for chronic active antibody-mediated rejection

Background

Chronic active antibody-mediated rejection (c-aABMR) is an important cause of allograft failure and graft loss in long-term kidney transplants.

Methods

To determine the efficacy and safety of combined therapy with rituximab, plasma exchange (PE) and intravenous immunoglobulins (IVIG), a cohort of patients with transplant glomerulopathy (TG) that met criteria of active cABMR, according to BANFF’17 classification, was identified.

Results

We identified 62 patients with active c-aABMR and TG (cg ≥ 1). Twenty-three patients were treated with the combination therapy and, 39 patients did not receive treatment and were considered the control group. There were no significant differences in the graft survival between the two groups. The number of graft losses at 12 and 24 months and the decline of eGFR were not different and independent of the treatment. A decrease of eGFR≥13 ml/min between 6 months before and c-aABMR diagnosis, was an independent risk factor for graft loss at 24 months (OR = 5; P = 0.01). Infections that required hospitalization during the first year after c-aABMR diagnosis were significantly more frequent in treated patients (OR = 4.22; P = 0.013), with a ratio infection/patient-year of 0.65 and 0.20 respectively.

Conclusions

Treatment with rituximab, PE, and IVIG in kidney transplants with c-aABMR did not improve graft survival and was associated with a significant increase in severe infectious complications.

Trial registration

Agencia Española de Medicametos y Productos Sanitarios (AEMPS): 14566/RG 24161. Study code: UTR-INM-2017-01.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1057-4) contains supplementary material, which is available to authorized users.

The relatively poor correlation between random and 24-hour urine protein excretion in patients with biopsy-proven glomerular diseases

Random urine protein creatinine ratios are used to estimate 24-hour urine protein excretion, which is considered a diagnostic gold standard. However, few studies are available of the sensitivity and specificity of this estimation in patients with glomerular proteinuria. To clarify this, we measured the urine protein and creatinine centrally in random and 24-hour urine collections at biopsy and longitudinally every 6 months in individuals participating in the Nephrotic Syndrome Study Network (NEPTUNE) cohort with glomerular disease. In the initial developmental cohort, 302 patients had same day random and 24-hour samples with a total of 827 paired measurements across all visits. The protein excretion (g/day) was higher in adult than pediatric patients. The correlation between the random urine protein creatinine ratio and 24-hour urine protein excretion was moderate in both groups (r of 0.60 and 0.67, respectively). However, the log₁₀ transformation of values strengthened correlations in both groups (r of 0.85 and 0.82, respectively). Associations were moderately stronger among obese patients. Prediction equations were developed and validated in 232 unique cases from NEPTUNE (R² of 0.65). Thus, in patients with glomerular disease and proteinuria, the urine protein creatinine ratio correlates only moderately with 24-hour urine protein excretion. However an estimating equation was developed to derive 24-hour urine protein excretion from random urine protein creatinine ratio values with improved precision. The long-term prognostic value of log₁₀-transformed random protein creatinine ratios values requires future study.

Increased plasma matrix metalloproteinase-2 (MMP-2), tissue inhibitor of proteinase-1 (TIMP-1), TIMP-2, and urine MMP-2 concentrations correlate with proteinuria in renal transplant recipients

BACKGROUND

The most frequent cause of kidney allograft loss is chronic allograft injury, often with proteinuria as the clinical feature. Occurrence of proteinuria late after kidney transplantation is associated with worse graft function and patient survival.

AIM

The aim of the study was to assess plasma and urine matrix metalloproteinases (MMP-2 and MMP-9) and tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) in proteinuric renal transplant recipients (RTRs). The factors were determined by enzyme-linked immunosorbent assay in 150 RTRs (51 women and 99 men), aged 49.2 ± 11.5 years, at mean 73.4 ± 41.2 months after kidney transplantation (range: 12 to 240 months).

RESULTS

Proteinuric RTRs compared with non-proteinuric RTRs had higher median plasma MMP-2 (P = .012), TIMP-1 (P = .0003), and TIMP-2 (P = .0021) concentrations, as well as higher urine MMP-2 (P < .0001) excretion. The presence of proteinuria had no impact on plasma MMP-9 and urine MMP-9, TIMP-1, and TIMP-2. Proteinuria and estimated daily proteinuria (uPr:uCr) correlated positively with plasma MMP-2 (rs = 0.226, P = .0054 and rs = 0.241, P = .003), TIMP-1 (rs = 0.305, P = .00015 and rs = 0.323, P = .000055), TIMP-2 (rs = 0.273, P = .0007 and rs = 0.269, P = .001) and urine MMP-2 (rs = 0.464, P < .0001 and rs = 0.487, P < .0001), respectively. Proteinuric RTRs had impaired graft function with higher median serum creatinine concentrations (1.91 [1.60-2.43] mg/dL versus 1.41 [1.20-1.65] mg/dL, P < .00001) and lower estimated glomerular filtration rate (36 [28-45] mL/min/1.73 m(2) versus 53 [43-61] mL/min/1.73 m(2), P < .00001) than RTRs without proteinuria.

CONCLUSIONS

Our research revealed that in RTRs, proteinuria was significantly associated with increased concentrations of enzymes involved in extracellular matrix (ECM) degradation: plasma MMP-2, TIMP-1, TIMP-2, and urine MMP-2. Findings strongly emphasize increased plasma TIMPs in proteinuric RTRs that inhibit degradation of ECM by MMPs and favor excessive deposition of ECM proteins.

Urinary protein/creatinine ratio weighted by estimated urinary creatinine improves the accuracy of predicting daily proteinuria

BACKGROUND

The spot urine protein/creatinine ratio (UPCR) is proposed to be a substitute for 24-hour urinary protein (24h-UP). This study is aimed to determine whether the predictive accuracy of 24h-UP using UPCR can be improved by simply multiplying estimated daily urine creatinine excretion (eUCr) and UPCR together.

METHODS

This study enrolled 120 participants to investigate the correlation between spot UPCR and 24h-UP. Three sets of spot urine samples were randomly collected throughout the day and night, along with the first morning void. UPCR was weighted by eUCr to investigate the improvement of accuracy in using spot urine samples to predict 24h-UP.

RESULTS

There were strong correlation and concordance between UPCR and 24h-UP irrespective of the time of spot urine sampling, and the correlation, concordance and agreement were improved after multiplying the UPCR value by the eUCr. Greater improvement was found in the subgroups with measured daily urine creatinine excretion ≤ 0.8 g/d and ≥ 1.2 g/d.

CONCLUSIONS

This investigation demonstrated that multiplying UPCR by eUCr can improve the accuracy of only using UPCR to predict 24h-UP.

Strong correlation between protein reagent strip and protein-to-creatinine ratio for detection of renal dysfunction in HIV-infected patients: a cross-sectional study

Background

Tubular dysfunction is common in HIV-infected people and detection of proteinuria is essential to identify this problem. In low-income countries, resources for detection of proteinuria using the Kidney Disease Improve Global Outcomes (KDIGO) gold standard urinary protein/creatinine ratio (uPCR) is rarely possible, and use of the protein reagent strip (PRS) could be an option in these places. The aims of this study were to establish the concordance between PRS and uPCR to detect tubular proteinuria in HIV-infected people, and to assess the sensitivity and specificity of PRS as a diagnostic method in this group.

Methods

A cross-sectional study was conducted to evaluate the correlation between the two techniques to detect protein in urine. Participants were enrolled for a period of 6 months. The measurements were performed in participants who were on highly active antiretroviral therapy (HAART) or prior to the start of treatment. Proteinuria was defined as uPCR ≥ 150 mg/g, and/or ≥ trace on PRS. A phi coefficient was calculated to establish the degree of correlation. We assessed the sensitivity and specificity of PRS compared with uPCR using standard methods.

Results

A total of 799 subjects were included. Of these, 737 (92%) were men. The mean age was 32.9 years (±10.1 years). Most (561, 70%) were on antiretroviral treatment. The mean estimated glomerular filtration rate (eGFR) calculated according to Modification of Diet in Renal Disease (MDRD)-4 was 113.0 mL/min (±22.6). Comorbidities included diabetes mellitus (10, 1.3%) and hypertension (17, 2.1%). The prevalence of proteinuria detected by PRS was 8.3% (n = 66) and by uPCR 10.6% (n = 85). The concordance assessed by phi correlation coefficient was 0.70, p < 0.001, with a sensitivity of 51.7% (95% confidence interval [CI] 41%–62%) and specificity 97% (95% CI 39%–97%).

Conclusions

There is a high concordance between detection of proteinuria by PRS and uPCR. Therefore, in low-income countries PRS can be helpful for detecting tubular damage in people infected with HIV.

Effects of cilnidipine on sympathetic nerve activity and cardiorenal function in hypertensive patients with type 2 diabetes mellitus: association with BNP and aldosterone levels

AIMS

Hypertension stimulates the sympathetic nervous system and this phenomenon is exacerbated by diabetes mellitus. We investigated the effects of cilnidipine, an N/L-type calcium channel blocker, on aspects of this system in patients with type 2 diabetes mellitus.

METHODS

In 33 hypertensive patients with type 2 diabetes mellitus treated with a calcium channel blocker other than cilnidipine, we evaluated the influence of switching to cilnidipine on blood pressure, heart rate, catecholamine, plasma renin and aldosterone concentration, brain natriuretic peptide, urine liver-type fatty acid binding protein, and urinary albumin excretion ratio in the same patients by a cross-over design. Other biochemical parameters were also evaluated.

RESULTS

Switching to cilnidipine did not change blood pressure but caused reduction in catecholamine concentrations in blood and urine and plasma aldosterone concentration, accompanied by significant reduction in brain natriuretic peptide, urine liver-type fatty acid binding protein, and albumin excretion ratio. These parameters other than brain natriuretic peptide were significantly increased after cilnidipine was changed to the original calcium channel blocker.

CONCLUSIONS

In 33 hypertensive patients with type 2 diabetes mellitus, compared to other calcium channel blockers, cilnidipine suppressed sympathetic nerve activity and aldosterone, and significantly improved markers of cardiorenal disorders. Therefore, cilnidipine may be an important calcium channel blocker for use in combination with renin-angiotensin-aldosterone system inhibitors when dealing with hypertension complicated with diabetes mellitus.

Quantifying proteinuria in hypertensive disorders of pregnancy

Background. Progressive proteinuria indicates worsening of the condition in hypertensive disorders of pregnancy and hence its quantification guides clinician in decision making and treatment planning. Objective. To evaluate the efficacy of spot dipstick analysis and urinary protein-creatinine ratio (UPCR) in hypertensive disease of pregnancy for predicting 24-hour proteinuria. Subjects and Methods. A total of 102 patients qualifying inclusion criteria were evaluated with preadmission urine dipstick test and UPCR performed on spot voided sample. After admission, the entire 24-hour urine sample was collected and analysed for daily protein excretion. Dipstick estimation and UPCR were compared to the 24-hour results. Results. Seventy-eight patients (76.5%) had significant proteinuria of more than 300 mg/24 h. Dipstick method showed 59% sensitivity and 67% specificity for prediction of significant proteinuria. Area under curve for UPCR was 0.89 (95% CI: 0.83 to 0.95, P < 0.001) showing 82% sensitivity and 12.5% false positive rate for cutoff value of 0.45. Higher cutoff values (1.46 and 1.83) predicted heavy proteinuria (2 g and 3 g/24 h, resp.). Conclusion. This study suggests that random urinary protein : creatine ratio is a reliable investigation compared to dipstick method to assess proteinuria in hypertensive pregnant women. However, clinical laboratories should standardize the reference values for their setup.

Does graft mass impact on pediatric kidney transplant outcomes?

BACKGROUND

The aim of this study is to assess the evolution of renal size and function in pediatric transplant patients according to the graft mass/recipient size ratio.

METHODS

Fifty pediatric renal transplant recipients were followed over 2 years. Grafts were weighed, and three different graft mass/m(2) ratios were determined: (1) low graft mass (58 g/m(2), range 31-57 g/m(2)), (2) median (142 g/m(2), range 59-141 g/m(2)) and high (267 g/m(2), range 143-353 g/m(2)). Patients underwent repeated ultrasound Doppler scans and repeated measurements of estimated glomerular filtration rate (eGFR; 1 week and 1, 6, 12 and 24 months), urinary retinol-binding protein (RBP) and proteinuria (1 week and 6, 12 and 24 months).

RESULTS

The volume of renal tissue increased by 12 ± 5.6 cm(3) at 24 months (p = 0.035) in the low graft mass and decreased by -14 ± 7 cm(3) (p = 0.046) in the high graft mass. The eGFR increased when either low (30 ± 5 ml/min/1.73 m(2), p < 0.001) or median (19 ± 4 ml/min/1.73 m(2), p < 0.001) graft mass was transplanted but remained stable when high graft mass was transplanted. The resistive index (RI) presented a significant decrease throughout early follow-up in the transplants involving low and median graft mass, whereas a slight rise was observed in those involving high graft mass. A significant difference was apparent 6 months post-transplant. Transplants of low and median graft mass were associated with an initial higher urinary RBP. No significant differences in proteinuria were detected.

CONCLUSIONS

Small kidneys undergo increases in volume and function without escalation of either proteinuria or urinary RBP, characterizing an adequate adaptation to the recipient. Children receiving larger kidneys present a reduction in volume, stable GFR and higher RI at 6 months.

Clinicopathological findings in non-human primate recipients of porcine renal xenografts: quantitative and qualitative evaluation of proteinuria

BACKGROUND

Immunological and histopathological features in pig-to-primate renal xenotransplantation are widely studied. Only limited data have been reported about clinicopathological findings in primate recipients of life-supporting renal xenografts. In human medicine, proteinuria represents a common complication in kidney transplantation and is associated with impaired graft survival. The detection of low molecular weight proteins of tubular origin is considered an early method for predicting potential graft rejection. In this study, the presence and the significance of quantitative and qualitative proteinuria were evaluated in xenotransplanted non-human primates in which kidney function was supported only by the transplanted organ.

METHODS

Eight bilaterally nephrectomized cynomolgus monkeys (Macaca fascicularis) were transplanted with a single kidney from α1,3-galactosyltransferase gene-knockout (GTKO) pigs transgenic for human CD39, CD55, CD59, and α1,2-fucosyltransferase. In addition to hematological and biochemical analyses, quantitative and qualitative analysis of proteinuria was evaluated by urinary protein-to-creatinine ratio (UPC ratio) and sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE), respectively.

RESULTS

The main hematological and biochemical changes recorded after transplantation were a progressive anemia and a severe and progressive decrease in total proteins. In urine samples, the UPC ratio was low before transplantation and increased after transplantation. Similarly, SDS-AGE was negative before transplantation, but bands consistent with mixed (i.e., tubular and glomerular) proteinuria were observed in all samples collected post-transplantation.

CONCLUSIONS

The study of clinicopathological changes in cynomolgus monkey renal xenograft recipients provides a valid help in monitoring the health conditions in the post-transplant period. Moreover, the evaluation of UPC ratio and the use of SDS-AGE technique in urine samples of cynomolgus monkey renal xenograft recipients may be considered a valid, inexpensive, and less time-consuming method than more sophisticated techniques in monitoring proteinuria. Proteinuria and presence of low molecular weight (LMW) proteins were consistently found in urine after transplantation, independent of fluctuations in renal function.

Random urine protein/creatinine ratio readily predicts proteinuria in preeclampsia

Objective

To assess the diagnostic accuracy of random urine protein-creatinine (P/C) ratio for prediction of significant proteinuria in preeclampsia as an alternative to the time-consuming 24-hour urine protein collection.

Methods

Retrospective record analysis was performed on 140 pregnant women who were admitted with suspicion for preeclampsia from January 2006 to June 2011. Random urine protein and/or 24-hour urine protein levels were assessed and their correlation to random urine P/C ratio and 24-hour urine protein excretion was evaluated.

Results

Out of 140 patients, random urine P/C ratio or/and 24-hour urine protein was performed in 79 patients to evaluate significant proteinuria. Of 79 patients, 46 (58%) underwent both tests whereas in 33 women (42%) 24-hour urine collection was not available due to urgent delivery. In 39 cases (85%), significant proteinuria (≥300 mg/24 hr) was detected with 6 cases (13%) having values over 5,000 mg/24 hr, corresponding to the diagnosis of severe preeclampsia. Random urine P/C ratio highly correlated with 24-hour urine protein excretion (r=0.823, P<0.01). The optimal random urine P/C ratio cutoff points were 0.63 and 4.68 for 300 mg/24 hr and 5,000 mg/24 hr of protein excretion, respectively. with each sensitivity, specificity, and positive and negative predictive values of 87.1%, 100%, 100%, and 58.3%; and 100%, 85%, 50%, and 100%, for significant and severe preeclampsia, respectively.

Conclusion

Random urine P/C ratio is a reliable indicator of significant proteinuria in preeclampsia and may be better at providing earlier diagnostic information than the 24-hour urine protein excretion with more accuracy than the urinary dipstick test.

Renal function and morphology in aged Beagle dogs before and after hydrocortisone administration

Objectives of this study were to evaluate glomerular filtration rate (GFR), renal structural changes and proteinuria in aged Beagle dogs before and after hydrocortisone (HC) administration. Eleven Beagle dogs ≥10 years old were treated with either hydrocortisone (HC group, n = 6) or placebo (control group, n = 5). Urinary markers, GFR and kidney biopsies were evaluated before (T0), during (T16 wks) and after discontinuing HC administration (T24 wks). Results indicate that HC administration causes a significant increase in GFR. At all time points except T16 wks, proteinuria was higher in the control group than in the HC group, and there was no significant difference in urinary markers between groups. At T16 wks, proteinuria, urinary albumin-to-creatinine (c) ratio, immunoglobulin G/c and retinol-binding protein/c were higher compared to baseline in the HC group. At T0, rare to mild renal lesions were detected in all HC dogs and rare to moderate changes in all control dogs. Glomerulosclerosis progressed in both groups until T24 wks. Tubular atrophy was detected in three HC dogs at T16 wks and T24 wks, but also in five control dogs throughout the study. At every time point, five HC dogs and all control dogs had rare to moderate interstitial inflammation. Rare to mild interstitial fibrosis was found in up to three HC dogs at T16 wks and T24 wks, and severe fibrosis in one HC dog at T24 wks. Up to four control dogs had rare to mild fibrosis at all time points. These findings indicate that clinically healthy, aged Beagle dogs may have considerable renal lesions and proteinuria, which could have implications for experimental or toxicological studies. Additional research is needed to elucidate glucocorticoid effects on renal structure, but functional changes such as hyperfiltration and proteinuria warrant attention to kidney function of canine patients with Cushing's syndrome or receiving exogenous glucocorticoids.

Posttransplantation proteinuria: an approach to diagnosis and management

Proteinuria is a common problem encountered in the treatment of renal transplant recipients, occurring in up to 45% of patients. Proteinuria from native kidneys falls rapidly after renal transplantation, and persistent or worsening proteinuria is usually indicative of allograft pathology. Biopsy studies of transplant patients with proteinuria have confirmed that transplant-specific diagnoses (transplant glomerulopathy, interstitial fibrosis and tubular atrophy, and acute rejection) are more commonly found than other proteinuric conditions, such as glomerulonephritis. As in the nontransplant setting, proteinuria is associated with worse clinical outcomes, including an increased risk for death, cardiovascular events, and graft loss. Blockade of the renin-angiotensin-aldosterone system with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers will reduce proteinuria, but the long-term effect of these medications on patient and graft survival remains unknown.

Assessment of proteinuria

Proteinuria is a strong predictor of adverse cardiovascular and kidney events, and an accurate assessment of proteinuria is important for the evaluation and management of CKD. Total urinary protein can be assessed using dipstick, precipitation, and electrophoresis methods. Urinary albumin, the predominant urinary protein in most proteinuric kidney diseases, can be assessed using an albumin-specific dipstick, immunochemical techniques, and size-exclusion high-performance liquid chromatography. Urine albumin may be immune-reactive, immune-unreactive, fragmented, and biochemically modified, and laboratory techniques have variable abilities to detect different types of albumin. Urine specimen for proteinuria assessment can either be obtained from a timed-collection or a spot urine sample. Spot urine protein- or albumin-to-creatinine ratios are preferred to a 24-hour urine sample in routine practice. Assessment of albuminuria rather than proteinuria is more clinically meaningful in patients with diabetic kidney disease, and proteinuria and albuminuria assessments both have a role in nondiabetic kidney disease and in general population screening. As measurement and sampling procedures for proteinuria assessment have yet not been standardized, it is important for physicians to be aware of different types of urinary proteins, albumins, laboratory techniques, and urine sampling methods.

[Is morning urinary protein-to-creatinine ratio a reliable estimator of 24-hour proteinuria in patients with kidney diseases?]

INTRODUCTION

Proteinuria is the most frequent marker of kidney damage. Although 24-hour urinary proteinuria is the gold standard, the measurement of proteinuria from albumin urinary creatinine ratio is proposed as much useful method.

OBJECTIVE

To evaluate the accuracy of urine protein-to-creatinine (P/Cr) ratio in morning urine specimens as compared with 24-hour total protein excretion for the measurement of proteinuria in patients with different kidney diseases and different renal function levels.

METHODS

Proteinuria in the studied patients was assessed by 24-hour protein excretion (24-hour PRT) and spot urine P/Cr ratio. The analysis of concordance between 24-hour PRT and P/Cr was carried out using intraclass correlation coefficient (ICC), paired t-test and Bland-Altman plots. The discriminant cutoff values for spot urine P/Cr ratio in predicting 24-hour protein "threshold" excretion were determined using receiver operating characteristic curves (ROC), as well as sensitivity and specificity.

RESULTS

A total of 303 patients were included in the study. The concordance between 24-hour PRT and P/Cr ratio was excellent (ICC 0.931). Systematic overestimation of PRT by urinary P/ Cr ratio was disclosed (mean difference 0.138, p = 0.011). The P/Cr of 0.25 (sensitivity 0.90; specificity 0.96), 0.66 (1.00; 0.91) and 2.55 (1.0; 0.97) g/g reliably predicted 24-hour urine total protein equivalent "thresholds" at 0.2, 1.0 and 3.5 g/day. The chronic renal failure group independently positively influenced the difference between 24-hour PRT and P/Cr. It means the lower the kidney function the higher is the difference between the two proteinuria measurements.

CONCLUSION

This study supports the recommendation of using spot urine P/Cr ratio in proteinuria screening in patients with different kidney diseases. The obtained results indicated better agreement between morning P/Cr and 24-hour PRT in patients with lower proteinuria and better kidney function.

Bevacizumab toxicities and their management in ovarian cancer

OBJECTIVES

The purpose of this review is to discuss the side effect profile of bevacizumab, to discuss proposed mechanisms of these toxicities, and to provide suggestions for management of adverse events.

METHODS

A search of MEDLINE and ASCO and SGO abstract databases of articles published between January 1970 and August 2009 addressing the toxicity of bevacizumab in solid tumors was conducted. Reporting was limited to best available evidence including any available phase III studies and ovarian cancer phase II studies. Original publications addressing underlying mechanisms of bevacizumab toxicities were included.

RESULTS

Extensive experience with bevacizumab has proven the agent to be generally well tolerated, with an adverse event profile distinct from traditional cytotoxic chemotherapy and likely peculiar to its novel mechanism of action. The most common bevacizumab-attributable adverse event, hypertension, can be medically-managed, but more serious adverse events such as bowel perforation require drug discontinuation.

CONCLUSIONS

Current best evidence supports the use of bevacizumab in selected patients, and safe administration of bevacizumab requires an understanding of the management of adverse events attributable to its use.

Urinary copper/zinc ratio: a promising parameter for replacement of 24-hour urinary copper excretion for diagnosis of Wilson's disease in children

BACKGROUND

Although 24-hour urinary copper excretion is valuable for diagnosis of Wilson's disease, accurate, timed collection entails practical difficulties. This study aimed to investigate the feasibility of morning urinary copper/creatinine or copper/zinc ratio as replacement parameter for diagnosing Wilson's disease.

METHODS

Five random urinary samples collected during 24 hours from two inpatients were used to estimate the consistency of urinary copper/creatinine and copper/zinc ratios. The correlation of the ratios with 24-hour urinary copper excretion was studied in 15 patients with liver diseases. The diagnostic value of morning urinary copper/zinc ratio was further studied in 9 children with Wilson's disease and 22 children with other liver diseases.

RESULTS

The coefficients of variation of urinary copper/creatinine and copper/zinc ratios during 24 hours were 12.5% and 9.3% respectively. The morning urinary copper/creatinine ratio, copper/zinc ratio, and 24-hour urinary copper excretion were correlated well. The area under receiver-operating characteristic curve was comparable between the morning urinary copper/zinc ratio and 24-hour urinary copper excretion (0.983 vs. 0.977).

CONCLUSION

Morning urinary copper/zinc ratio seems to be a promising parameter in replacement of 24-hour urinary copper excretion for diagnosis of Wilson's disease.

Usage of spot urine protein to creatinine ratios in the evaluation of preeclampsia

OBJECTIVE

The objective of the study was to prospectively compare spot urine protein to creatinine (P:C) ratios with 24 hour urine collections for protein in women being evaluated for preeclampsia.

STUDY DESIGN

A spot urine P:C ratio was obtained at the beginning of 24 hour urine collections from 126 patients admitted to evaluate for preeclampsia. Correlation between the spot P:C ratio with the 24 hour urine collections was calculated. Receiver operator characteristic curves were constructed to determine best P:C cut-offs for 300 mg and 5000 mg protein per 24 hours.

RESULTS

Random spot P:C ratios were strongly correlated with 24 hour urine protein levels (Pearson r = 0.88). The optimal P:C cut-offs were 0.21 (300 mg per 24 hours) and 3.0 (5000 mg per 24 hours). A P:C ratio of less than 0.21 (300 mg per 24 hours) had a negative predictive value (NPV) of 83.3% and a P:C ratio of less than 3.0 (5000 mg per 24 hours) had 100% NPV.

CONCLUSION

Urine spot P:C ratio correlated well with 24 hour urine collections for protein but was not justified as a substitute for timed collections.

Comparison between 24-h proteinuria, urinary protein/creatinine ratio and dipstick test in patients with nephropathy: patterns of proteinuria in dipstick-negative patients

OBJECTIVE

Three main tests are commonly employed for the measurement of proteinuria: the dipstick test, the urinary protein/creatinine ratio (P/C) and the 24-h urine collection. The aim of this study was to evaluate the correlation between these methods, comparing linear regression and ROC curve data.

MATERIAL AND METHODS

A total of 297 consecutive outpatients with different renal diseases were included in the study. Twenty-four-hour proteinuria was considered the reference test.

RESULTS

A high degree of correlation was observed between all the tests (p<0.0001), the highest regression coefficient being between 24-h proteinuria and P/C (R=0.82), and the lowest between P/C and the dipstick test (R=0.72). The dipstick test failed to detect pathological proteinuria in 94 patients (31.6%). Therefore, in these subjects, the patterns of proteinuria were assessed by immunofixation and sodium dodecyl sulphate (SDS) electrophoresis.

CONCLUSIONS

Our data strongly support the use of urinary P/C for the detection of proteinuria, at least in nephrology units, where the prevalence of proteinuria is likely to be high.

Proteomic research in renal transplantation

Expression proteomics is a valuable tool for biomarker discovery. Currently there is a great deal of interest in the development of urine biomarkers for detection of renal allograft rejection as an alternative to percutaneous needle biopsy, which is the "gold standard." Needle biopsy is costly and associated with significant patient morbidity and mortality. This review will discuss the author's current work in proteomics-based urine biomarker discovery, as well as alternative approaches used by other groups that use SELDI mass spectrometry. The current state of urine transplant biomarkers will be discussed, and in conclusion there will be a brief discussion of how urine biomarkers will be used for transplant patient management once they are validated and analyte-specific assays are developed.

Use of protein:creatinine ratio measurements on random urine samples for prediction of significant proteinuria: a systematic review

BACKGROUND

Proteinuria is recognized as an independent risk factor for cardiovascular and renal disease and as a predictor of end organ damage. The reference test, a 24-h urine protein estimation, is known to be unreliable. A random urine protein:creatinine ratio has been shown to correlate with a 24-h estimation, but it is not clear whether it can be used to reliably predict the presence of significant proteinuria.

METHODS

We performed a systematic review of the literature on measurement of the protein:creatinine ratio on a random urine compared with the respective 24-h protein excretion. Likelihood ratios were used to determine the ability of a random urine protein:creatinine ratio to predict the presence or absence of proteinuria.

RESULTS

Data were extracted from 16 studies investigating proteinuria in several settings; patient groups studied were primarily those with preeclampsia or renal disease. Sensitivities and specificities for the tests ranged between 69% and 96% and 41% and 97%, respectively, whereas the positive and negative predictive values ranged between 46% and 95% and 45% and 98%, respectively. The positive likelihood ratios ranged between 1.8 and 16.5, and the negative likelihood ratios between 0.06 and 0.35. The cumulative negative likelihood ratio for 10 studies on proteinuria in preeclampsia was 0.14 (95% confidence interval, 0.09-0.24).

CONCLUSION

The protein:creatinine ratio on a random urine specimen provides evidence to "rule out" the presence of significant proteinuria as defined by a 24-h urine excretion measurement.

Assessment of Factors Determining Graft Size in Transplant of Cadaver Kidneys from Child Donors

BACKGROUND

Kidneys from child donors are very efficient at adapting to the recipient organism. This research aims to verify the size of kidney grafts from pediatric donors after transplant and to identify factors responsible for the size attained by these kidneys. Moreover, it aims to seek relationships between size and function of the transplanted pediatric kidney.

METHODS

Seventy-seven renal transplants performed at least 6 months earlier, with cadaver donor 15 years old or younger, had ultrasound measurements of the graft and renal function assessment. Potential factors for graft volume were analyzed using bivariate analysis, followed by multiple linear regression.

RESULTS

After a follow up of 4.2+/-3.3 years posttransplant, the grafts presented the following range of measures: length 10.61+/-1.13 cm, width 4.67+/-0.84 cm, and depth 4.76+/-0.99 cm. Graft volumes were 126.62+/-47.76 cm. Bivariate analysis showed that (1) age of both donor and recipient at transplantation; (2) sex of recipient; (3) occurrence of acute rejection episodes were statistically significant. After multivariate analysis, age and sex of recipients were the only significant factors influencing graft volume; child kidneys reached greater volumes when transplanted into adult and male individuals. Larger volume kidneys presented significantly more proteinuria. No difference was evident with regard to creatinine clearance values or urinary retinol binding protein among kidneys of differing sizes.

CONCLUSIONS

The size of the recipient (age and sex) is the main factor responsible for volumes achieved by kidneys from pediatric donors. The volume attained by these kidneys demonstrated no relationship with glomerular or tubular function of the organ.

Rapid resolution of proteinuria of native kidney origin following live donor renal transplantation

To assess the contribution of the protein content of urine from the native kidneys to post-transplant proteinuria, we prospectively studied 14 live donor transplant recipients with a pre-transplant random urine protein to creatinine ratio (UPr:Cr) >0.5. Seven patients received preemptive transplants, and seven patients were on dialysis pre-transplant (with residual urine output). Resolution of proteinuria was defined as UPr:Cr < 0.2. Immunosuppression consisted of tacrolimus, mycophenolate mofetil and corticosteroids. Anti-hypertensive drugs that might reduce proteinuria were avoided during the study. The serum creatinine was 8.7 +/- 0.7 mg/dL pre-transplant, and the nadir post-transplant serum creatinine was 1.4 +/- 0.1 mg/dL. The pre-transplant UPr:Cr ranged between 0.5 and 9.2 (mean = 2.9 +/- 0.6). The UPr:Cr decreased to <0.2 in all 14 patients at a mean of 4.5 weeks post-transplant (range 1-10 weeks). In conclusion, in live donor renal transplant recipients with immediate graft function, proteinuria of native kidney origin resolves in the early post-transplant period. After the immediate post-transplant period, proteinuria cannot be attributed to the native kidneys, and work up for proteinuria should focus on the allograft.

Protein-to-creatinine ratio in spot urine samples as a predictor of quantitation of proteinuria

BACKGROUND

Normal individuals usually excrete very small amounts of protein in the urine. Persistently increased protein excretion is usually a marker of kidney damage. Quantifying protein in urine is commonly used in the diagnosis of kidney diseases, detection of treatment effects and evaluation of prognosis. We evaluated the use of the total protein-to-creatinine ratio (P/C) in spot urine specimens as a predictor of urine protein excretion in 24-h collections.

METHODS

The correlation between P/C in first morning and random urine specimens and urinary protein excretion in 24-h collections were analyzed. The cutoff value of P/C in first morning urine specimens for screening urinary protein excretion of 1 and 3 g in 24-h collections was determined by receiver operating characteristics (ROC) curve.

RESULTS

For patients with Ccr<or=10 ml/min, correlation between the urine protein excretion in 24-h collections and the P/C in first morning urine specimens was not significant. For patients with Ccr > 10 ml/min, the correlation was highly significant. Similar results were obtained for random urine specimens. By ROC curve analysis, the P/C of 0.94 and 2.84 g/gcr in first morning urine specimens represent the best threshold to detect urine protein excretion of 1 and 3 g in 24-h collections, respectively. There is a good correlation between P/C in first morning urine specimens and random urine specimens from inpatients and outpatients. But the P/C in random specimens is significantly higher than that in first morning specimens in outpatients.

CONCLUSION

The P/C in spot urine samples could be used as an alternative to urine protein excretion in 24-h collections in patients with Ccr>10 ml/min. The P/C in first morning urine samples is better than that in random specimens, especially for outpatients.

Characterization of renal allograft rejection by urinary proteomic analysis

OBJECTIVE

To develop a diagnostic method with no morbidity or mortality for the detection of acute renal transplant rejection.

SUMMARY BACKGROUND DATA

Rejection constitutes the major impediment to the success of transplantation. Currently available methods, including clinical presentation and biochemical organ function parameters, often fail to detect rejection until late stages of progression. Renal biopsies have associated morbidity and mortality and provide only a limited sample of the organ.

METHODS

Thirty-four urine samples were collected from 32 renal transplant patients at various stages posttransplantation. Samples were collected from 17 transplant recipients with acute rejection and 15 patients with no rejection. Samples from patients less than 4 days posttransplant were omitted from data analysis due to the presence of excessive inflammatory response proteins. Rejection status was confirmed by kidney biopsy. Specimens were analyzed in triplicate using SELDI mass spectrometry. The obtained spectra were subjected to bioinformatic analysis using ProPeak as well as CART (Classification and Regression Tree) algorithms to identify rejection biomarker candidates. These candidates were identified by their molecular weight and ranked by their ability to distinguish between nonrejection and rejection based on receiver operating characteristic (ROC) analysis. The candidates with the highest area under the ROC curve (AUC) exhibited the best diagnostic performance.

RESULTS

The best candidate biomarkers demonstrated highly successful diagnostic performance: 6.5 kd (AUC = 0.839, P <.0001), 6.7 kd (AUC = 0.839, P <.0001), 6.6 kd (AUC = 0.807, P <.0001), 7.1 kd (AUC = 0.807, P <.0001), and 13.4 kd (AUC = 0.804, P <.0001). A separate analysis using the CART algorithm in the Ciphergen Biomarker Pattern Software correctly classified 91% of the 34 specimens in the training set, giving a sensitivity of 83% and specificity of 100% using two separate biomarker candidates at 10.0 kd and 3.4 kd.

CONCLUSIONS

Biomarker candidates exist in urine that have the ability to distinguish between renal transplant patients with no rejection and those with acute rejection. These biomarker candidates are the basis for development of a noninvasive method of diagnosing acute rejection without the morbidity and mortality associated with needle biopsy. The combination of biomarkers into a panel for diagnosis leads to the possibility of enhanced diagnostic performance.

Windows to the ward: graphically oriented report forms. Presentation of complex, interrelated laboratory data for electrophoresis/immunofixation, cerebrospinal fluid, and urinary protein profiles

BACKGROUND

Automated laboratory analyzers that mass produce data have been linked to information systems for more than two decades, but little progress has been made in developing more comprehensible report forms. Results are still reported in computer-generated printouts containing hundreds of numbers crowded into columns on each printed page.

METHODS

We developed three software applications focusing on the graphic presentation of laboratory results.

RESULTS

The first application summarizes data for a patient with a monoclonal gammopathy. The report provides a cumulative graphic presentation of immunofixation/electrophoresis data without any additional interpretation, focuses on a color-coded electrophoresis scan, and records up to 5 years on a single page. The second application deals with cerebrospinal fluid analysis. The report calculates relevant data and graphs the complex relationship between albumin and immunoglobulin results from paired serum and cerebrospinal fluid samples. Manually added interpretive text assures an output comprehensible to clinicians in all specialties. The third application produces a report summarizing quantitatively measured urinary marker protein profiles. The report form is generated by a flexible, completely user-definable knowledge-based system. It calculates numerous ratios and formulae, supports reflex testing, supplies an automated interpretation, and generates a specific graphic signature pattern of the results (MDI LabLink proteinuria differentiation).

CONCLUSIONS

Increased clinical demand for graphically oriented report forms 5 years after their introduction has provided evidence that these reports transfer complex laboratory data and results to the clinician more effectively. The highest (more than threefold) increase in demand has been for reports for urinary marker protein profiles that feature a largely self-explanatory graphic signature pattern.