Objective To investigate the application value of virtual touch tissue quantification (VTQ) technique in staging of chronic kidney disease (CKD). Methods VTQ examination was performed on a random sample of 96 CKD patients at different clinical stages and 45 healthy volunteers (control group). Shear wave velocity (SWV) of renal parenchyma was measured and compared. Correlation between SWV and clinical stage and glomeru-lar filtration rate (GFR) of CKD patients was analyzed. Results The SWV value of renal parenchyma decreased gradually, along with the progression of CKD disease and impairment of renal function. There was no significant difference(P>0.05)between the control group and the CKD1 group ( P=0.061), the CKD2 group and the CKD3 group (P = 0.238), and the CKD4 group and the CKD5 group (P = 0.624). The difference of SWV between the remaining groups was statistically significant(P < 0.05). SWV of renal parenchyma was negatively correlated with CKD stage (r =-0.65, P < 0.001), which means the higher the stage of CKD was associated with the lower the SWV. SWV was positively correlated with GFR (r = 0.73, P < 0.001), which means the lower the GFR was related to the lower the SWV. Conclusion VTQ technique can noninvasively reflect the changes of renal parenchyma elas-ticity and evaluate the impairment of renal function in CKD patients. It can provide a new quantitative evaluation index for the clinical staging of CKD.

Objective To view and compare the clinical characteristics of renal tubular acidosis in adults and children.Methods Clinical data of patients with renal tubular acidosis diagnosed by Shandong Provincial Hospital affiliated to Shandong University from Jan 1991 to Sep 2017 were reviewed.The difference and consistency in clinical characteristics of renal tubular acidosis between adults and children were analyzed.Results Data from 206 adults and 60 children were analyzed.89.81％ cases in adults were secondary to other diseases,mainly primary Sjogren's syndrome.Most children patients (81.67％) were idiopathic,others largely originated from inherited metabolic diseases.The most common subtype of both was distal renal tubular acidosis.Proximal renal tubular acidosis was easier to be found in idiopathic renal tubular diseases of children.Chief complaints or starting symptoms were mainly composed of polydipsia with polyuria (41.4％) and fatigue (35.3％).Children were typical of growth retardation,rickets and digestive symptoms.The rate of missed diagnosis and misdiagnosis was 41.4 percent.Routine therapy consisted of healing metabolic acidosis and electrolyte disorders,treating underlying diseases and preventing complications.The majority of patients (95.5％) improved after treatments.Conclusions Renal tubular acidosis possesses various underlying diseases,diverse clinical manifestation and high rate of misdiagnosis.Given the high incident of secondary types,investigation of underlying disease,especially autoimmune diseases such as Sjogren's syndrome,is of great importance in adults.Most children patients suffer from primary renal tubular acidosis.Attention should be paid to them in order to reduce the rate of misdiagnosis and teratogenicity.