Renal cortical stiffness obtained by shear wave elastography imaging is increased in patients with type 2 diabetes mellitus without diabetic nephropathy

J Ultrasound. 2018 Dec;21(4):279-285. doi: 10.1007/s40477-018-0315-4. Epub 2018 Jul 26.

Abstract

Purpose: It is known that patients with type 2 diabetes mellitus (DM) who develop diabetic nephropathy have increased renal cortical stiffness (CS) determined by shear wave elastography (SWE). However, there is no data in the literature to our knowledge related to CS values determined by SWE in type 2 DM patients with normal renal function. In this study, we aimed to investigate the change of renal CS obtained by SWE examination in type 2 DM patients with normal renal function compared to non DM patients.

Methods: A total of 103 patients (86 males, 17 females and mean age 63.2 ± 11.8 years) with or without type 2 DM were included in the study. The eGFR value of all patients was > 60 ml/kg/1.732. Routine history, physical examination and laboratory examinations were performed. In addition to routine renal ultrasonography (USG), renal resistive index (RRI), renal pulsatility index (RPI), accelerated time (AT), and CS were measured.

Results: Fifty patients with type 2 DM and 53 patients without type 2 DM were included in the study. Patients with type 2 DM had higher blood glucose, blood urea nitrogen and HbA1c levels (p < 0.05 each one). Renal length and width and echogenicity were similar between two groups with conventional renal USG. Renal parenchyma thickness was higher in patients with type 2 DM. When the findings of renal Doppler USG were examined, RRI was similar between two groups. RPI and AT were higher in patients with type 2 DM. CS values obtained with renal SWE were significantly higher in patients with type 2 DM (p < 0.05).

Conclusion: Cortical stiffness value obtained by SWE is significantly higher in type 2 DM patients with normal renal function compared to patients without DM. We recommend CS measurement as part of routine screening of nephropathy in patients with type 2 DM and normal renal function to guide management and treatment plan.

Obiettivo: I pazienti con diabete mellito di tipo 2 (DM2) che sviluppano nefropatia diabetica hanno un’aumentata stiffness (rigidità) renale corticale (CS) all’elastografia in modalità shear wave. Tuttavia, non ci sono dati in letteratura relativi a valori di CS in pazienti diabetici con funzione renale normale. In questo studio, abbiamo voluto indagare le differenze fra la CS di pazienti diabetici rispetto ai pazienti non diabetici.

Materiali e metodi: Sono stati inclusi nello studio 103 pazienti (86 maschi, 17 femmine, età media 63,2 ± 11,8 anni), tra cui 50 diabetici (DM2) e 53 non diabetici. Il valore di eGFR di tutti i pazienti è risultato > 60 ml/kg/1.732. A tutti i pazienti sono stai effettuati: raccolta dell’anamnesi, esame obiettivo, esami di laboratorio di routine, ecografia renale (USG), indice di resistenza renale (RRI), indice di pulsatilità renale (RPI), tempo di accelerazione (AT), e stiffness corticale misurata con elastografia shear wave.

Risultati: Nei 50 pazienti diabetici abbiamo riscontrato aumentata glicemia, azotemia, ed HbA1c (p < 0,05 ciascuno). Le dimensioni, l’ecogenicità e la RRI dei reni sono risultate sovrapponibili fra i due gruppi di pazienti, mentre lo spessore parenchimale, RPI, AT e CS con SWE (p < 0.05) sono risultati più elevati nei pazienti diabetici.

Conclusione: La stiffness corticale ottenuta mediante SWE è significativamente maggiore nei pazienti diabetici con funzione renale normale rispetto ai pazienti senza DM, pertanto il nostro suggerimento è di includere la misurazione della stiffness con elastografia nello screening della nefropatia nei pazienti diabetici per guidarne la gestione e la terapia.

Keywords: Diabetes mellitus; Nephropathy; Renal cortical stiffness; Shear wave elastography.

MeSH terms

  • Diabetes Mellitus, Type 2 / diagnostic imaging*
  • Diabetes Mellitus, Type 2 / physiopathology
  • Diabetic Nephropathies / diagnostic imaging
  • Diabetic Nephropathies / physiopathology
  • Elasticity Imaging Techniques* / methods
  • Female
  • Humans
  • Kidney / diagnostic imaging*
  • Kidney / physiopathology
  • Kidney Diseases / diagnostic imaging*
  • Kidney Diseases / physiopathology
  • Male
  • Middle Aged