Multicenter evaluation of use of dried blood spot compared to conventional plasma in measurements of globotriaosylsphingosine (LysoGb3) concentration in 104 Fabry patients.

OBJECTIVES: Fabry disease (FD) is an X-linked lysosomal storage disorder, resulting from a deficiency of the enzyme α-galactosidase A, responsible for breaking down glycolipids such as globotriaosylceramide and its deacylated derivative, globotriaosylsphingosine (LysoGb3). Here, we compare the levels of LysoGb3 in dried blood spots (DBS) and plasma in patients with classic and late-onset phenotypes. METHODS: LysoGb3 measurements were performed in 104 FD patients, 39 males and 65 females. Venous blood was collected. A portion was spotted onto filter paper and another portion separated to obtain plasma. The LysoGb3 concentrations in DBS and plasma were determined by highly sensitive electrospray ionization liquid chromatography tandem mass spectrometry. Agreement between different matrices was assessed using linear regression and Bland Altman analysis. RESULTS: The method on DBS was validated by evaluating its precision, accuracy, matrix effect, recovery, and stability. The analytical performances were verified by comparison of a total of 104 paired DBS and plasma samples from as many FD patients (representing 46 GLA variants). There was a strong correlation between plasma and the corresponding DBS LysoGb3 concentrations, with few exceptions. Discrepancies were observed in anemic patients with typically low hematocrit levels compared to the normal range. CONCLUSIONS: The method proved to be efficient for the rapid analysis of LysoGb3. DBS provides a convenient, sensitive, and reproducible method for measuring LysoGb3 levels for diagnosis, initial phenotypic assignment, and therapeutic monitoring in patients with FD.

1,25 Dihydroxyvitamin D circulating levels, calcitriol administration, and incidence of acute rejection, CMV infection, and polyoma virus infection in renal transplant recipients.

Observation that 1,25-Dihydroxyvitamin-D3 has an immunomodulatory effect on innate and adaptive immunity raises the possible effect on clinical graft outcome. Aim of this study was to evaluate the correlation of biopsy-proven acute rejection, CMV infection, BKV infection, with 1,25-Dihydroxyvitamin-D3 deficiency and the benefit of calcitriol supplementation before and during the transplantation. Risk factors and kidney graft function were also evaluated. All RTRs received induction therapy with basiliximab, cyclosporine, mycophenolic acid, and steroids. During the first year, the incidence of BPAR (4% vs 11%, P=.04), CMV infection (3% vs 9%, P=.04), and BKV infection (6% vs 19%, P=.04) was significantly lower in users compared to controls. By multivariate Cox regression analysis, 1,25-Dihydroxyvitamin-D3 deficiency and no calcitriol exposure were independent risk factors for BPAR (HR=4.30, P<.005 and HR=3.25, P<.05), for CMV infection (HR=2.33, P<.05 and HR=2.31, P=.001), and for BKV infection (HR=2.41, P<.05 and HR=2.45, P=.001). After one year, users had a better renal function: eGFR was 62.5±6.7 mL/min vs 51.4±7.6 mL/min (P<.05). Only one user developed polyomavirus-associated nephropathy vs 15 controls. Two users lost their graft vs 11 controls. 1,25(OH)2-D3 deficiency circulating levels increased the risk of BPAR, CMV infection, BKV infection after kidney transplantation. Administration of calcitriol is a way to obtain adequate 1,25(OH)2-D3 circulating levels.

Pre-Dialysis B-Line Quantification at Lung Ultrasound Is a Useful Method for Evaluating the Dry Weight and Predicting the Risk of Intradialytic Hypotension.

Intradialytic hypotension (IDH) is a frequent and well-known complication of hemodialysis, occurring in about one third of patients. An integrated approach with different methods is needed to minimize IDH episodes and their complications. In this prospective observational study, recruited patients underwent a multiparametric evaluation of fluid status through a lung ultrasound (LUS) with the quantification of B-lines, a physical examination, blood pressure, NT-proBNP and chest X-rays. The evaluation took place immediately before and at the end of the dialysis session, and the patients were divided into IDH and no-IDH groups. We recruited a total of 107 patients. A pre-dialysis B-line number ≥ 15 showed a high sensitivity in fluid overload diagnosis (94.5%), even higher than a chest X-ray (78%) or physical examination (72%) alone. The identification at the beginning of dialysis of <8 B-lines in the overall cohort or <20 B-lines in patients with NYHA 3−4 class are optimal thresholds for identifying those patients at higher risk of experiencing an IDH episode. In the multivariable analysis, the NYHA class, a low pre-dialysis systolic BP and a low pre-dialysis B-line number were independent risk factors for IDH. At the beginning of dialysis, the B-line quantification at LUS is a valuable and reliable method for evaluating fluid status and predicting IDH episodes. A post-dialysis B-line number <5 may allow for an understanding of whether the IDH episode was caused by dehydration, probably due to due to an overestimation of the dry weight.

Lung ultrasound may help in the differential diagnosis of suspected oligosymptomatic COVID-19 patients on hemodialysis: A case report.

INTRODUCTION: Considering that patients on dialysis showed a poor outcome during COVID-19 pandemic, and that COVID-19 symptoms in dialysis patients are often mild or absent, each dialysis unit should implement local strategies to early recognize patients affected by COVID-19. However, many available SARS-CoV-2 diagnostic tests demonstrated a moderate sensitivity, 70%-80% is probably a reasonable estimate. Consequently, having useful tools for differential diagnosis becomes essential. In this scenario, lung ultrasound (LUS) may have an important role in the evaluation of lung involvement in hemodialysis patients during COVID-19 pandemic. METHODS: We present two cases of hemodialysis patients with COVID-19 pneumonia in whom LUS had a central role in the diagnostic process. Ultrasound images of COVID-19 pneumonia show a typical bilateral pattern characterized by multiple or confluent B-lines with spared areas, thickened and irregular pleural line, and rare subpleural consolidations. LUS showed high accuracy in diagnosing COVID-19 pneumonia. FINDINGS: Despite both patients appeared clinically euvolemic and afebrile, they presented with acute diarrhea and oxygen saturation level of 92%-93%. Although clinical manifestations were mild and not specific in both patients, LUS raised suspicion on the possible COVID-19 diagnosis which was confirmed by a positive nasopharyngeal RT-PCR. DISCUSSION: There are many reasons for a patient on dialysis to present shortness of breath, fever, and multiple B-lines at LUS assessment (such as heart failure, fluid overload, vascular access infection, interstitial pneumonia) but the recognition of typical ultrasound patterns of the COVID-19 pneumonia is helpful for differential diagnosis. LUS may have an important role in the screening process of hemodialysis patients during the COVID-19 pandemic, especially in oligosymptomatic patients before the SARS-CoV-2 diagnostic tests, and in those with suspected symptoms and/or known exposure with unexpected negative SARS-CoV-2 diagnostic tests.

Optical Coherence Tomography Angiography for the Evaluation of Retinal Vasculature in Fabry Disease: Our Experience and Review of Current Knowledge.

Purpose: Optical coherence tomography angiography (OCTA) is a non-invasive and objective tool for the evaluation of the retinal microvascular changes in Fabry disease (FD). We investigated changes in retinal vasculature in FD patients, and the possible correlation with systemic parameters, by using OCTA, and reviewed the current status of literature. Methods: Thirteen FD patients (eight females, five males, mean age 49.85 ± 14.7 years) were compared with 13 age- and sex-matched healthy controls. OCTA 3 × 3 mm macular scans were performed in all subjects. We evaluated the vessel density and vessel perfusion in distinct macular areas (whole, inner, and outer) of both the superficial capillary plexus (SCP VD and SCP VP) and of the deep capillary plexus (DCP VD and DCP VP). We also evaluated the foveal avascular zone (FAZ) metrics (area, perimeter, and circularity), and correlation between systemic and OCTA parameters. A literature review on the current understanding of OCTA in FD is then presented. Results: FD patients showed significantly lower SCP VD values in the whole area (17.37 ± 2.08 mm-1 vs. 18.54 ± 1.21 mm-1; p-value 0.022), as well as in the outer area (17.46 ± 2.10 mm-1 vs. 19.08 ± 1.14 mm-1; p-value 0.002), but not in the inner. Even the DCP VD was significantly lower in all the imaged areas: whole (17.75 ± 3.93 mm-1 vs. 19.71 ± 1.20 mm-1; p-value 0.024), outer (18.25 ± 4.17 mm-1 vs. 20.33 ± 1.20 mm-1; p-value 0.023), and inner (19.54 ± 4.17 mm-1 vs. 21.96 ± 1.55 mm-1; p-value 0.011). There were no significant differences in vessel perfusion parameters (both SCP VP and DCP VP ones) and FAZ. No significant correlations were found between the OCTA parameters and systemic parameters (maximal left ventricular wall thickness and glomerular filtration rate) in FD patients. Conclusions: OCTA can be considered as a promising non-invasive tool, which enables a quantitative evaluation of retinal vascular involvement in FD, despite the varying data reported in literature. Our results support the use of OCTA as an objective tool to evaluate retinal vascular abnormalities in FD. The utility of OCTA in FD needs to be validated by longitudinal studies taking into account the overall progression of the disease.

[Free light chains reduction on acute kidney injury in multiple myeloma: critical role of high cut-off membranes]. / Il trattamento del danno renale acuto in corso di mieloma multiplo: ruolo della rimozione delle catene leggere libere con membrane ad elevato cut-off.

We report our experience with five patients, with dialysis dependent AKI and multiple myeloma (MM). Two of them were already suffering from a mild degree of renal insufficiency, one was on follow-up for smouldering MM and two had a relapse of symptomatic MM. Median concentration of the involved FLC (iFLC) was 15104 mg/L (range 1196-24384). All patients underwent three times per week HCO-HD for 6 hour sessions using Theralite 2100 (median 10, range 6-13 sessions) with one having further twelve sessions of 4 hours using SUPRA device (Bellco). In addition, they followed a bortezomib and dexamethasone regimen according to a bi-weekly schedule (3-5 cycles) plus Thalidomide. iFLC concentrations were measured by immunonephelometry in blood at the beginning of each dialysis session. All patients but one, showed a very good partial hematological response. The only exception demonstrated a partial response. iFLCs decreased between 72,8% and 99,7% in a median period of three weeks. After 6 months three patients underwent autologous stem-cell transplantation (ASCT), one of whom repeated the procedure 6 months later. In conclusion, three patients became dialysis independent at the end of the HCO-HD period, one patient became dialysis independent three months later and one remained dialysis dependent. Recovery of renal function in 4 out of 5 patients with a very good hematological response is a consequence of an early and fast removal of the iFLC joined to an efficient therapeutic regimen.