RESUMO
AIMS: The aim of this cohort study was to evaluate the association between urinary levels of C-megalin, a full-length form of megalin, and kidney dysfunction progression and its dependence on the urinary albumin-creatinine ratio (UACR) in individuals with diabetes. METHODS: We enrolled 1,547 individuals with diabetes who visited the ambulatory clinic at Tenri Hospital, a regional tertiary-care hospital in Tenri City, Nara Prefecture, Japan, with an estimated glomerular filtration (eGFR) of ≥ 30 mL/min/1.73 m2. The hazard ratio (HR) and 95% confidence interval (CI) were estimated using Cox proportional hazard models to examine the association between urinary C-megalin levels and eGFR decline by ≥ 40% from baseline. RESULTS: Urinary C-megalin level was not associated with ≥ 40% eGFR decline in an age-, sex-, eGFR-, systolic blood pressure-, hemoglobin-, and UACR-adjusted model in the 1,547 patients enrolled in the study. However, urinary C-megalin levels were associated with a ≥ 40% decline in eGFR when accounting for the relationship between urinary C-megalin levels and UACR in the model. This association was UACR-dependent. CONCLUSIONS: High urinary C-megalin levels were associated with progressive kidney dysfunction in individuals with diabetes, and this association was attenuated by high UACRs.
Assuntos
Diabetes Mellitus Tipo 2 , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Humanos , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Rim , Sistema de Registros , Taxa de Filtração Glomerular , Albuminúria/etiologia , Albuminúria/complicaçõesRESUMO
A 72-year-old man with type 2 diabetes mellitus with good glucose control for 20 years and maintained on oral hypoglycaemic agents was diagnosed with Hodgkin's Lymphoma (HL) and started on insulin glargine for glycaemic control. Despite increased doses of insulin, his blood glucose levels went up dramatically. The anti-insulin antibody test proved to be positive, and Scatchard plot analysis showed 2 binding sites with relatively low-affinity constants: K 1 = 0.0032, K 2 = 0.0002 (108/M); and high binding capacities: R 1 = 98.4, R 2 = 372 (10-8 M), which were compatible with the features of antibody of insulin autoimmune syndrome (IAS). However, hypoglycaemia was not noted throughout the course of treatment. Since the insulin binding ratio of the antibody decreased from 87.3% to 62% after the termination of insulin treatment, it was suggested that the antibody reacted mainly to exogenously injected insulin. Switching insulin preparations or introducing insulin secretagogues did not improve elevated blood glucose levels. The initiation of brentuximab vedotin (BV), a therapeutic agent for relapsed HL, resulted in a remarkable improvement in glycaemic control despite the absence of insulin therapy and partial remission of HL. This case suggested that HL triggered anti-insulin antibody production, which resulted in poor glycaemic control, and that BV could be a new treatment option for autoimmune diseases associated with HL. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-021-00550-1.
RESUMO
BACKGROUND: A urinary biomarker sensitive to glomerular functional or structural changes in diabetic kidney disease is required. This study examined whether urinary C-megalin reflects renal function or albuminuria in diabetes. METHODS: This was a cross-sectional study involving 1576 patients with type 1 or 2 diabetes. The exposure variables were estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR), and the outcomes were urinary C-megalin excretion and concentration. Two-part models were used to examine the associations between eGFR and UACR with urinary C-megalin excretion or concentration. RESULTS: The UACR was linearly associated with urinary C-megalin excretion (per 100 mg/gCr of UACR; 11.8 fM/gCr [95% CI 8.9-14.7]). There was no association between decreasing eGFR and increasing urinary C-megalin excretion. The UACR was also linearly associated with the urinary C-megalin concentration (per 100 mg/gCr of UACR, 7.7 fM/L [95% CI 5.8-9.6]). At eGFR values > 60 mL/min/1.73 m2, the eGFR and urinary C-megalin concentration were inversely linearly related (per 10 mL/min/1.73 m2 decline, 7.7 fM/L [95% CI 0.2-15.1]). CONCLUSION: Urinary C-megalin excretion as well as concentration levels are potentially useful biomarkers to detect early changes in diabetic kidney disease.
Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Albuminúria/complicações , Albuminúria/etiologia , Creatinina/urina , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/etiologia , Taxa de Filtração Glomerular , Humanos , Rim/fisiologia , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Sistema de RegistrosRESUMO
AIMS: Megalin is a multiligand receptor expressed in proximal tubular cells that reabsorbs filtered albumin and correlates cross-sectionally with albuminuria. We investigated the association between urinary C-megalin levels and the incidence of microalbuminuria in patients with diabetes mellitus. METHODS: This cohort study included 752 patients with type 1 or 2 diabetes mellitus and a urinary albumin-to-creatinine (Cr) ratio (UACR) within the normoalbuminuric range (<30 mg/g Cr). The association between urinary C-megalin and persistent microalbuminuria, accounting for the possible interaction between baseline UACR and urinary C-megalin, was estimated using a Cox proportional hazards model. RESULTS: During a median follow-up period of 1.99 years, 179 cases of persistent microalbuminuria were observed. The association between urinary C-megalin and persistent microalbuminuria was UACR-dependent (P for interaction < 0.001), with the highest association observed in the absence of UACR (per 100 fM/gCr of urinary C-megalin: adjusted hazard ratio, 1.13; 95% CI 1.07-1.19), gradually decreasing as UACR increased to 30 mg/g Cr. UACR dependence was confirmed by sensitivity analyses according to low-normal (<10 mg/gCr) or high-normal (10-<30 mg/gCr) UACR. CONCLUSIONS: Urinary C-megalin is associated with progression to microalbuminuria, especially in those with low-normal UACR levels, and its usefulness to identify high risk patients requires further investigation.