Immunohistochemical Diagnosis of Amyloid Typing: Utility and Limitations as Determined by Liquid Chromatography-Tandem Mass Spectrometry.

BACKGROUND: Although immunohistochemical techniques and proteomic analysis are widely used for typing diagnosis of amyloidosis, the diagnostic utility of immunohistochemical evaluation is not well understood. METHODS: We used immunohistochemical techniques to characterize staining patterns of in-house rabbit polyclonal anti-κ, anti-λ, anti-transthyretin antibodies, and commercial anti-amyloid A and anti-ß2-microglobulin antibodies in 40 autopsy cases. RESULTS: In thirty cases (75%), the subtype was determined by using the criterion that amyloid is strongly and diffusely positive for one antibody while negative for other antibodies. We then performed proteomic analysis of all 40 cases. In 39 cases, we identified only one amyloid protein and confirmed the immunohistochemically determined subtypes of the abovementioned 30 cases. In seven other cases, we could retrospectively determine subtypes with immunohistochemistry by using information from proteomic analysis, which increased the immunohistochemistry diagnosis rate to 92.5% (37/40). In one case, we identified double subtypes, both immunohistochemically and with proteomic analysis. In the remaining three cases, proteomic analysis was essential for typing diagnosis. CONCLUSIONS: The present findings suggest that combined immunohistochemistry and proteomic analysis is more useful than immunohistochemistry alone. Our findings highlight the importance of carefully interpreting immunohistochemistry for anti-TTR and light chain and offer insights that can guide amyloid typing through immunohistochemistry.

Higher serum ß2-microglobulin is a predictive biomarker for cognitive impairment in spinal cord injury.

Objective: Recent studies have suggested that high levels of ß2-microglobulin are linked to cognitive deterioration; however, it is unclear how this connects to spinal cord injury (SCI). This study sought to determine whether there was any association between cognitive decline and serum ß2-microglobulin levels in patients with SCI. Methods: A total of 96 patients with SCI and 56 healthy volunteers were enrolled as study participants. At the time of enrollment, specific baseline data including age, gender, triglycerides (TG), low-density lipoprotein (LDL), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), smoking, and alcohol use were recorded. Each participant was assessed by a qualified physician using the Montreal cognitive assessment (MoCA) scale. Serum ß2-microglobulin levels were measured using an enzyme-linked immunosorbent assay (ELISA) reagent for ß2-microglobulin. Results: A total of 152 participants were enrolled, with 56 in the control group and 96 in the SCI group. There were no significant baseline data differences between the two groups (p > 0.05). The control group had a MoCA score of 27.4 ± 1.1 and the SCI group had a score of 24.3 ± 1.5, with the difference being significant (p < 0.05). The serum ELISA results revealed that the levels of ß2-microglobulin in the SCI group were considerably higher (p < 0.05) than those in the control group (2.08 ± 0.17 g/mL compared to 1.57 ± 0.11 g/mL). The serum ß2-microglobulin level was used to categorize the patients with SCI into four groups. As serum ß2-microglobulin levels increased, the MoCA score reduced (p < 0.05). After adjustment of baseline data, further regression analysis showed that serum ß2-microglobulin level remained an independent risk factor for post-SCI cognitive impairment. Conclusions: Patients with SCI had higher serum levels of ß2-microglobulin, which may be a biomarker for cognitive decline following SCI.

Pathological review of cardiac amyloidosis using autopsy cases in a single Japanese institution.

AIM: Amyloidosis is a systemic or localized disease of protein deposition characterized by amorphous eosinophilic morphology and positivity of Congo Red staining. The typing of amyloidosis is becoming increasingly important because therapeutic agents for each amyloidosis type have been developed. Herein, the authors review the autopsy cases at an institution to reveal the putative Japanese characteristics of each amyloidosis type and evaluate the clinicopathological significance of each type. MATERIALS AND METHODS: A total of 131 autopsy cases of systemic and localized amyloidosis were retrieved for classification by immunohistochemistry. Immunohistochemistry for transthyretin, amyloid A (AA), immunoglobulin light-chain kappa and lambda, and ß2-microglobulin was performed for all cases. RESULTS: The 131 amyloidosis cases were classified as follows: 71 cases (54.2%) of transthyretin amyloidosis, 32 cases (24.4%) of AA amyloidosis, 8 cases (6.1%) of light-chain amyloidosis, and 5 cases (3.8%) of ß2-microglobulin amyloidosis, along with 15 equivocal cases (11.5%). All cases showed myocardial involvement of amyloidosis. Histopathologically, the transthyretin type was significantly associated with the interstitial and nodular patterns, and with the absence of the perivascular and endocardial patterns. The AA type was significantly associated with the perivascular and endocardial patterns, and with the absence of the nodular pattern. CONCLUSION: The authors revealed the putative characteristics of cardiac amyloidosis in Japan by using autopsy cases. About 90% of amyloidosis cases were successfully classified using only commercially available antibodies.

Circulating low CD4+/CD8+ ratio is associated with poor prognosis in Waldenstrom macroglobulinemia patients.

Waldenstrom macroglobulinemia (WM) is a rare type of non-Hodgkin lymphoma with great heterogeneity, and the data of peripheral blood T-lymphocyte subsets in WM are limited. This study aimed to investigate the clinical correlation and distribution of circulating T-lymphocyte subsets in newly diagnosed WM patients. We retrospectively searched medical records for 86 newly diagnosed WM patients. Comparisons of the absolute CD3+ T-lymphocyte count (ACD3C), CD4+ T-lymphocyte count (ACD4C), CD8+ T-lymphocyte count (ACD8C), and CD4+/CD8+ T-lymphocyte ratio (CD4+/CD8+) as continuous parameters in different groups were calculated. Univariate and multivariate analyses were used to assess prognostic factors for overall survival (OS) and progression-free survival (PFS). Young patients (<65 years) had lower ACD8C levels and a higher CD4+/CD8+ ratio. And the lower level of ß2-microglobulin (<3 mg/L) was associated with a higher CD4+/CD8+ ratio. With a median follow-up of 25 months, the univariate survival analysis showed that CD4+/CD8+ ratio inversion (CD4+/CD8+<1.5) was associated with shorter OS and PFS, and multivariate analysis confirmed that inverted CD4+/CD8+ ratio could be an independent adverse prognostic factor for OS and PFS. Additionally, initial treatment with rituximab or bortezomib significantly improved the PFS and OS of CD4+/CD8+ inversion patients but did not affect normal CD4+/CD8+ patients. We show that low circulating CD4+/CD8+ ratio at diagnosis is an adverse prognostic factor in WM patients and that first-line therapy which included rituximab or bortezomib significantly improved PFS and OS for patients with CD4+/CD8+ ratio less than 1.5.

Biomarker Discovery in Patients with Immunotherapy-Treated Melanoma with Imaging Mass Cytometry.

PURPOSE: Imaging mass cytometry (IMC) is among the first tools with the capacity for multiplex analysis of more than 40 targets, which provides a novel approach to biomarker discovery. Here, we used IMC to characterize the tumor microenvironment of patients with metastatic melanoma who received immunotherapy in efforts to find indicative factors of treatment response. In spite of the new power of IMC, the image analysis aspects are still limited by the challenges of cell segmentation. EXPERIMENTAL DESIGN: Here, rather than segment, we performed image analysis using a newly designed version of the AQUA software to measure marker intensity in molecularly defined compartments: tumor cells, stroma, T cells, B cells, and macrophages. IMC data were compared with quantitative immunofluorescence (QIF) and digital spatial profiling. RESULTS: Validation of IMC results for immune markers was confirmed by regression with additional multiplexing methods and outcome assessment. Multivariable analyses by each compartment revealed significant associations of 12 markers for progression-free survival and seven markers for overall survival (OS). The most compelling indicative biomarker, beta2-microglobulin (B2M), was confirmed by correlation with OS by QIF in the discovery cohort and validated in an independent published cohort profiled by mRNA expression. CONCLUSIONS: Using digital image analysis based on pixel colocalization to assess IMC data allowed us to quantitively measure 25 markers simultaneously on formalin-fixed, paraffin-embedded tissue microarray samples. In addition to showing high concordance with other multiplexing technologies, we identified a series of potentially indicative biomarkers for immunotherapy in metastatic melanoma, including B2M.

Síndrome de hiperviscosidade em paciente com mieloma múltiplo / Hyperviscosity syndrome in multiple myeloma patients

O mieloma múltiplo é uma neoplasia progressiva e incurável de células B, caracterizado pela proliferação desregulada e clonal de plasmócitos na medula óssea. A síndrome de hiperviscosidade é uma das complicações relacionadas às gamopatias monoclonais, sendo considerada emergência oncológica. O objetivo deste estudo foi descrever o quadro clínico de um paciente diagnosticado com mieloma múltiplo que apresentou síndrome de hiperviscosidade, avaliando a prevalência de sinais e sintomas, bem como características fisiopatológicas dessa entidade clínica. Foi revisado o prontuário de um paciente internado na enfermaria da Clínica Médica do Hospital Regional do Cariri (CE) no período de junho a julho de 2018. Além disso, foi realizada revisão de literatura em base de dados (PubMed®) direcionada ao tema proposto. O diagnóstico de mieloma múltiplo foi comprovado por mielograma, sendo prontamente iniciada a corticoterapia e avaliada a resposta clínica após essa terapêutica. Apesar de incomum e menos frequentemente relacionada ao mieloma múltiplo, a síndrome de hiperviscosidade está relacionada a uma grande taxa de mortalidade quando apresenta diagnóstico tardio. A terapia de primeira linha indicada para a síndrome de hiperviscosidade foi a plasmaferese, no entanto, as condições clínicas (instabilidade hemodinâmica) impossibilitaram sua realização. O desfecho deste caso foi o óbito do paciente. Concluiu-se que o diagnóstico precoce e a intervenção terapêutica estão diretamente relacionados à ocorrência de menor incidência de complicações relacionadas ao mieloma múltiplo e à síndrome de hiperviscosidade.

Multiple myeloma is a progressive and incurable B-cell neoplasm characterized by unregulated and clonal proliferation of plasmocytes in the bone marrow. Hyperviscosity syndrome is one of the complications related to monoclonal gammopathies and is considered an oncological emergency. The aim of this study was to describe the clinical condition of a patient diagnosed with multiple myeloma who presented hyperviscosity syndrome, evaluating the prevalence of symptoms and signs, as well as the pathophysiological characteristics of this clinical entity. The medical records of a patient admitted to the Internal Medicine ward of the Hospital Regional do Cariri (CE) from June to July of 2018 were reviewed. In addition, we conducted a literature review in a database (PubMed®) directed to the theme proposed. The diagnosis of multiple myeloma was confirmed by myelogram, and corticosteroid therapy was promptly initiated and the clinical response was evaluated after this therapy. Although uncommon and less frequently related to multiple myeoloma, hyperviscosity syndrome is related to a high mortality rate when diagnosed late. The first line therapy indicated to hyperviscosity syndrome was plasmapheresis; however, the clinical conditions (hemodynamic instability) precluded its performance. The outcome of this case was the patient's death. Thus, it was concluded that early diagnosis and therapeutic intervention are directly related to the occurrence of lower incidence of complications related to multiple myeloma and hyperviscosity syndrome.

A nomogram to predict cadmium-induced renal tubular dysfunction.

Cadmium-induced renal dysfunction varies between individuals. It would be valuable to figure out those susceptible individuals or predict the risk of cadmium induced renal dysfunction. In the present study, we used a nomogram model to identify high-risk of cadmium-induced renal tubular dysfunction. 342 subjects living in low and moderately cadmium polluted areas were included in this study. The daily cadmium intake from food (FCd) was estimated using food survey. The cadmium in blood (BCd) and urine (UCd) were detected by using flame atomic absorption spectrometry. Urinary ß2Microglobulin (UBMG) was chosen as indicator of renal dysfunction. Logistic regression was used to select the independent risk factors for renal dysfunction. Bootstrap self-sampling and calibration curves were performed to quantify our modeling strategy. Age, sex, BCd and TCd were used to construct the nomogam in total population; age, BCd and TCd were adopted in women; age and BCd were used in men. The internal validation showed the C-index was 0.76 (95% 47 confidence interval (CI): 0.71-0.82) in total population, 0.74 (95% CI: 0.69-0.79) in men and 0.78 (95% CI: 0.72-0.84) in women. The area under the curve of the nomogram was 0.77 (95% CI: 0.71-0.83) in total population, 0.82(95% CI: 0.74-0.90) in women and 0.74(95% CI: 0.66-0.82) in men. Nomogram may be a rapid and simple risk assessment tool for predicting high-risk of renal tubular dysfunction in subjects exposed cadmium.

Clinical characteristics and prognostic values of 1p32.3 deletion detected through fluorescence in situ hybridization in patients with newly diagnosed multiple myeloma: a single-center study in China.

This study aimed to investigate the prevalence, clinical characteristics, and prognostic impact of 1p32.3 deletion in patients with newly diagnosed multiple myeloma (MM). A retrospective analysis was conducted on 411 patients with newly diagnosed MM; among which, 270 received bortezomib-based therapies, and 141 received thalidomide-based therapies. Fluorescence in situ hybridization (FISH) was performed to detect six cytogenetic abnormalities, namely, del(1p32.3), gain(1q21), del(17p13), del(13q14), t(4;14), and t(11;14). Results showed that 8.3% of patients with MM were detected with del(1p32.3) and had significantly more bone marrow plasma cells (P = 0.025), higher ß2-microglobulin levels (P = 0.036), and higher lactate dehydrogenase levels (P = 0.042) than those without del(1p32.3). Univariate analysis showed that patients with del(1p32.3) under thalidomide-based therapies (median PFS 11.6 vs. 31.2 months, P = 0.002; median OS 16.8 vs. 45.9 months, P < 0.001) were strongly associated with short progression-free survival (PFS) (P = 0.002) and overall survival (OS) (P < 0.001). Multivariate analysis revealed that del(1p32.3) remained a powerful independent factor with worse PFS (P = 0.006) and OS (P = 0.016) for patients under thalidomide-based treatments. Patients with del(1p32.3) under bortezomib-based treatments tended to have short PFS and OS. In conclusion, del(1p32.3) is associated with short PFS and OS in patients with MM who received thalidomide- or bortezomib-based treatments.

The inhibitory receptor CD94/NKG2A on CD8+ tumor-infiltrating lymphocytes in colorectal cancer: a promising new druggable immune checkpoint in the context of HLAE/ß2m overexpression.

We previously demonstrated that HLA-E/ß2m overexpression by tumor cells in colorectal cancers is associated with an unfavorable prognosis. However, the expression of its specific receptor CD94/NKG2 by intraepithelial tumor-infiltrating lymphocytes, their exact phenotype and function, as well as the relation with the molecular status of colorectal cancer and prognosis remain unknown. Based on a retrospective cohort of 234 colorectal cancer patients, we assessed the expression of HLA-E, ß2m, CD94, CD8, and NKp46 by immunohistochemistry on tissue microarray. The expression profile of HLA-E/ß2m on tumor cells and the density of tumor-infiltrating lymphocytes were correlated to the clinicopathological and molecular features (Microsatellite status, BRAF and RAS mutations). Then, from the primary tumors of 27 prospective colorectal cancers, we characterized by multiparameter flow cytometry the nature (T and/or NK cells) and the co-expression of the inhibitory NKG2A or activating NKG2C chain of ex vivo isolated CD94+ tumor-infiltrating lymphocytes. Their biological function was determined using an in vitro redirected cytolytic activity assay. Our results showed that HLA-E/ß2m was preferentially overexpressed in microsatellite instable tumors compared with microsatellite stable ones (45% vs. 19%, respectively, p = 0.0001), irrespective of the RAS or BRAF mutational status. However, HLA-E/ß2m+ colorectal cancers were significantly enriched in CD94+ intraepithelial tumor-infiltrating lymphocytes in microsatellite instable as well as in microsatellite stable tumors. Those CD94+ tumor-infiltrating lymphocytes mostly corresponded to CD8+ αß T cells, and  to a lesser extent to NK cells, and mainly co-expressed a functional inhibitory NKG2A chain. Finally, a high number of CD94+ intraepithelial tumor-infiltrating lymphocytes in close contact with tumor cells was independently associated with a worse overall survival. In conclusion, these findings strongly suggest that HLA-E/ß2m-CD94/NKG2A represents a new druggable inhibitory immune checkpoint, preferentially expressed in microsatellite instable tumors, but also in a subgroup of microsatellite stable tumors, leading to a new opportunity in colorectal cancer immunotherapies.

The potential diagnostic power of CD138+ microparticles from the plasma analysis for multiple myeloma clinical monitoring.

Multiple myeloma (MM) is malignant tumor with abnormal proliferation of bone marrow plasma cells. The existing clinical tools used to determine treatment response and tumor relapse are limited in sensitivity. We investigated the CD138+ microparticles (MPs) of MM patients to find out whether MPs could provide a novel means to monitor the malignant cells in MM patients. Our study showed that the levels of MPs were significantly elevated in MM patients. The MP counts in peripheral blood from new diagnosed MM patients were significantly higher than patients in CR and HD. Consist with the total MPs, the number of the PC-derived MPs (CD138+) increased in BM from MM patients compared with CR and HD. The ratio of the PC-derived MPs (CD138+) in BM increased in MM patients compared with CR and HD. The correlation test revealed that the CD138+ MPs in BM and PB were all positively correlated with the plasmacyte ratio in bone marrow (BMPC) and the ß2 -MG. New diagnosed MM patients and controls were compared, and ROC curves were used to identify cutoff points with optimal sensitivity and specificity concerning the ratios and counts of CD138+ MPs in BM and PB. The AUC of the CD138+ MP counts in BM was 0.767, and in PB was 0.680. The AUC of the CD138+ MP ratios in BM was 0.714, and in PB was 0.666. According to this, the counts of CD138+ MPs in BM showed to be a powerful marker of diagnosis. We demonstrated that CD138+ MPs from the plasma provide support for a potential monitoring biomarker of MM.

Immunoglobulin D (IgD) and IgD receptor expression in diffuse large B-cell lymphoma.

Objective: Immunoglobulin D (IgD) levels are often elevated in patients with autoimmune diseases. However, the oncogenic activities of IgD and IgD receptor (IgDR) in diffuse large B-cell lymphoma (DLBCL) have not been reported in detail. Therefore, we aimed to investigate the expression of IgD and IgDR in patients with DLBCL. Methods: Membrane IgD (mIgD) and IgDR expression in tissue samples was analyzed using IHC, mIgD and IgDR expression on peripheral blood mononuclear cells (PBMCs) was analyzed by FCM, and secreted IgD (sIgD) level was analyzed by ELISA. Fisher's exact test and Spearman correlation analysis were used to evaluate the relationship between IgD, IgDR, and clinical parameters. Results: The pathological lymph nodes of 34 patients with DLBCL were studied, and mIgD and IgDR expression was found in 16 and 19 patients. mIgD and IgDR expression was upregulated in patients with DLBCL and mIgD expression was significantly associated with IgDR expression. Further correlation analysis showed that mIgD expression was correlated with serum ß2-MG level and Hans algorithm as germinal center B (GCB), whereas IgDR expression correlated with serum LDH level, IPI score and GCB. ELISA showed that sIgD level was significantly increased in DLBCL patients and it correlated with serum ß2-MG and LDH levels. FCM showed that mIgD and IgDR expression in PBMCs of patients with DLBCL was significantly higher than that in healthy controls. Conclusion: Our findings suggest that overexpression of IgD and IgDR is an abnormal activation state in DLBCL.

Discrepancy of Serological and Molecular Patterns of Circulating Epstein-Barr Virus Reactivation in Primary Sjögren's Syndrome.

Primary Sjögren's syndrome (pSS) is characterized by B cell hyperactivation, production of autoantibodies and increased risk of B cell lymphomas. Serological profile of Epstein-Barr virus (EBV) reactivation and increase EBV DNA levels in exocrine glands are observed in pSS, but whether these abnormalities are accompanied with disturbed systemic EBV control or have any association with pSS activity remains to be investigated. In this observational study, we initially explored anti-EBV antibodies and cell-free DNA in 395 samples from a cross-sectional plasma collection of pSS patients included in ASSESS French national cohort. Results were assessed in relation with disease activity. Further, to assess cell-associated EBV DNA we organized a case-control study including 20 blood samples from pSS patients followed in University Hospital Center of Montpellier. Results were compared with matched controls. Robust response against EBV early antigen (EA) was observed in pSS patients with anti-SSA/B (Sjögren's syndrome A and B) and anti-SSA autoantibodies compared to anti-SSA/B negatives (P < 0.01 and P = 0.01, respectively). Increased beta-2 microglobulin, kappa and lambda light chains, and immunoglobulin G levels were more frequently observed in anti-EA seropositive pSS subjects compared to anti-EA negative subjects (P < 0.001; P = 0.001; P = 0.003, respectively). Beta-2 microglobulin was independently associated with anti-EA positivity in multivariate analysis (P < 0.001). Plasma cell-free EBV DNA and EBV cellular reservoir was not different between pSS patients and controls. We conclude that serological evidence of EBV reactivation was more frequently observed and more strongly associated with anti-SSA/B status and B cell activation markers in pSS. However, serological profile of EBV reactivation was not accompanied by molecular evidence of systemic EBV reactivation. Our data indicated that EBV infection remains efficiently controlled in the blood of pSS patients.

[Quantitative determination of the beta-2-microglobulin monomer by gel filtration chromatography].

Beta-2-microglobulin (B2M) is an important material in dialysis-related amyloidosis research. Unfortunately, the quantitative detection of the B2M monomer is difficult during B2M production. In this study, we established a method for the detection of the B2M monomer and its dimer in solution via gel filtration chromatography. The B2M powder was dissolved in 0.01 mol/L phosphate-buffered solution (PBS, pH 7.2-7.4) with a final mass concentration of 0.5 g/L. The B2M sample was analyzed on a TSKgel SuperSW2000 column (30 cm×4.6 mm, 4 µm) by an Agilent 1200 Series HPLC using 0.01 mol/L PBS (pH 7.2-7.4) as the mobile phase at a flow rate of 0.5 mL/min. The temperature of the column was 25℃, and the detection wavelength was 280 nm. The purities of the B2M monomer and the B2M dimer were tested. A series of concentrations of B2M monomer solutions were prepared to create a standard working curve. The standard working curve of the B2M monomer had a good linear relationship (coefficient of correlation (r2) was 0.9948). The limit of quantitation for the B2M monomer in PBS was 0.08 g/L (S/N=10). The recoveries were 85.0%-96.7% with relative standard deviations of 1.7%-3.3% at spiked levels of 0.10-0.30 g/L. The quantification of the B2M monomer was undisturbed by the B2M dimer, which can form during the B2M purification process. This determination method is simple, stable, and reliable for the determination of the B2M monomer in B2M industrial production.

Impact of age on clinical risk scores in follicular lymphoma.

The Follicular Lymphoma (FL) International Prognostic Index (FLIPI) and FLIPI-2 are well-described clinical risk models. Age >60 years at diagnosis is a risk factor in both scores. Recently, we showed that older age is not associated with higher risk of disease progression or inferior treatment efficacy. Instead, shorter survival of older patients results mainly from an increased risk of nonrelapse deaths. This questions the value of age as a meaningful component of scores intended to predict disease-specific survival. The newly proposed PRIMA-prognostic index (PRIMA-PI) only includes ß2-microglobulin levels and bone marrow infiltration as risk factors. Here, we independently validate the PRIMA-PI in a clinical trial cohort of 475 patients with advanced FL who uniformly received cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, prednisone, and rituximab (R-CHOP) as frontline therapy. The PRIMA-PI separated 3 similar sized risk cohorts with 5-year progression-free survival (PFS) rates of 74%, 59%, and 39%, respectively (P < .0001). Furthermore, we compare the PRIMA-PI with the FLIPI and FLIPI-2. We demonstrate that the PRIMA-PI has the highest specificity to identify high-risk patients (80% for 5-year PFS) because of its superior risk stratification in patients >60 years (73% vs 33% [FLIPI] and 47% [FLIPI-2] for 5-year PFS). Thus, the PRIMA-PI is a promising clinical tool to stringently identify patients at highest risk of poor outcome after frontline R-CHOP for advanced FL, and is particularly useful in patients with older age. Further validation in non-R-CHOP treated cohorts is needed.

Novel glomerular filtration markers.

Chronic kidney disease is currently assessed by estimated glomerular filtration rate, a mathematical construct based on creatinine or creatinine and cystatin concentration. Creatinine-based equations have improved with standardization efforts and the Modification of Diet in Renal Disease Study (MDRD) and CKD-Epidemiology Collaboration Study (CKD-EPI). Because the measurement of creatinine is subject to interference from non-GFR determinants, alternative markers have long been sought. These have included cystatin C and low molecular weight proteins like ß2-microglobulin and beta trace protein. Tubular disease often occurs before glomerular filtration is impaired and investigators have investigated the excretion of other low molecular weight proteins such as Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Kidney Injury Molecule-1 and N-acetyl-ß-d-glucosaminidase. While preliminary, there is some evidence linking these analytes with GFR, disease stage and mortality. Although asymmetrical dimethyl arginine, an inhibitor of nitric oxide, has been shown to be associated with progression of renal disease, symmetric dimethyl arginine may be a better marker. Recent work has also explored the potential of microRNA (miRNA) analysis and metabolomics studies to further elucidate this complex pathophysiologic disease process. Investigators hope to improve our ability to detect CKD by the use of test panels, i.e., various marker combinations thereof. Unfortunately, most of these markers lack standardization unlike traditional measures that rely on creatinine and cystatin C measurement.

The relationships between markers of tubular injury and intrarenal haemodynamic function in adults with and without type 1 diabetes: Results from the Canadian Study of Longevity in Type 1 Diabetes.

OBJECTIVE: Our aim was to define the relationships between plasma biomarkers of kidney injury and intrarenal haemodynamic function (glomerular filtration rate [GFR], effective renal plasma flow [ERPF], renal vascular resistance [RVR]) in adults with type 1 diabetes (T1D). METHODS: The study sample comprised patients with longstanding T1D (duration ≥50 years), among whom 44 were diabetic kidney disease (DKD) resistors (eGFR >60 mL/min/1.73 m2 and <30 mg/d urine albumin excretion) and 22 had DKD, in addition to 73 control participants. GFRINULIN and ERPFPAH were measured, RVR was calculated, and afferent (RA )/efferent (RE ) areteriolar resistances were derived from Gomez equations. Plasma neutrophil gelatinase-associated lipocalin (NGAL), ß2 microglobulin (B2M), osteopontin (OPN) and uromodulin (UMOD) were measured using immunoassay kits from Meso Scale Discovery. RESULTS: Plasma NGAL, B2M and OPN were higher and UMOD was lower in DKD patients vs DKD resistors and non-diabetic controls. In participants with T1D, plasma NGAL inversely correlated with GFR (r = -0.33; P = 0.006) and ERPF (r = -0.34; P = 0.006), and correlated positively with RA (r = 0.26; P = 0.03) and RVR (r = 0.31; P = 0.01). In participants without T1D, NGAL and B2M inversely correlated with GFR (NGAL r = -0.18; P = 0.13 and B2M r = -0.49; P < 0.0001) and with ERPF (NGAL r = -0.19; P = 0.1 and B2M r = -0.42; P = 0.0003), and correlated positively with RA (NGAL r = 0.19; P = 0.10 and B2M r = 0.3; P = 0.01) and with RVR (NGAL r = 0.20; P = 0.09 and B2M r = 0.34; P = 0.003). Differences were significant after adjusting for age, sex, HbA1c, SBP and LDL. There were statistical interactions between T1D status, B2M and intrarenal haemodynamic function (P < 0.05). CONCLUSIONS: Elevated NGAL relates to intrarenal haemodynamic dysfunction in T1D, whereas elevated NGAL and B2M relate to intrarenal haemodynamic dysfunction in adults without T1D. These data may define a diabetes-specific interplay between tubular injury and intrarenal haemodynamic dysfunction.

Multiple myeloma: Updated approach to management in 2018.

BACKGROUND: Multiple myeloma is an uncommon haematological cancer of plasma cells. Improvements in understanding of this disease have lead to drastic changes regarding diagnosis, management and its prognosis. OBJECTIVE: The aim of this article is to provide a concise update regarding the current management of myeloma in Australia, and important management issues for general practitioners. DISCUSSION: With the advent of new treatments, the outcomes of myeloma have changed drastically in the past decade, and it is now a disease that requires long-term monitoring by both haematologists and general practitioners.

Diagnostic markers for CNS lymphoma in blood and cerebrospinal fluid: a systematic review.

Diagnosing central nervous system (CNS) lymphoma remains a challenge. Most patients have to undergo brain biopsy to obtain tissue for diagnosis, with associated risks of serious complications. Diagnostic markers in blood or cerebrospinal fluid (CSF) could facilitate early diagnosis with low complication rates. We performed a systematic literature search for studies on markers in blood or cerebrospinal fluid for the diagnosis CNS lymphoma and assessed the methodological quality of studies with the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2). We evaluated diagnostic value of the markers at a given threshold, as well as differences between mean or median levels in patients versus control groups. Twenty-five studies were included, reporting diagnostic value for 18 markers in CSF (microRNAs -21, -19b, and -92a, RNU2-1f, CXCL13, interleukins -6, -8, and -10, soluble interleukin-2-receptor, soluble CD19, soluble CD27, tumour necrosis factor-alfa, beta-2-microglobulin, antithrombin III, soluble transmembrane activator and calcium modulator and cyclophilin ligand interactor, soluble B cell maturation antigen, neopterin and osteopontin) and three markers in blood (microRNA-21 soluble CD27, and beta-2-microglobulin). All studies were at considerable risk of bias and there were concerns regarding the applicability of 15 studies. CXCL-13, beta-2-microglobulin and neopterin have the highest potential in diagnosing CNS lymphoma, but further study is still needed before they can be used in clinical practice.