肾功能检查1全解

LOGO
Renal damage:
Chronic renal failure
• Compensatory stage: BUN<9mmol/L • Decompensatory stage: BUN>9mmol/L • Failure stage: BUN>20mmol/L
Excessive intake of protein and proteolysis:
high protein diet，high fever, Upper gastrointestinal hemorrhage, extensive burn， severe trauma, hyperthyroidism
Clinical Significance of BUN/Cr
LOGO
Prerenal oliguria: BUN升高更明显，BUN/Cr 明显升高
Structure of Kidney
LOGO
肾小体 肾 单 位 肾小管
肾小球
肾小囊 近曲小管 髓袢 远曲小管
集 合 管
FUNCTIONS OF KIDNEY Excrete metabolic products/wastes
LOGO
Keep the balance of water, acid-base and electrolyte Endocrine function:
Ccr (ml/min) Ucr(mg/dl) xV(volume of urine/min) Pcr (mg/dl)
Normal value： 80-120 ml/min
Clinical Significance
Physiologiccal ：related with sports, diets, age…… Pathological decrease
Serum Creatinine, Scr
Blood Urea Nitrogen, BUN
Serum β2-microglobulin
Cystatin C
Glomerular Filtration Renal blood flow ： 1200-1400ml/min，
LOGO
占20%-25%心血流量
80-51
50-20 19-10 <10
<178
178～445 445-707 >707
<9
9～20 20-28.6 >28.6
Cystatin C 胱氨酸蛋白酶抑制剂 C
LOGO
Expressed in all nucleated cells, encoded by house keeping gene Can be detected in all body fluid Almost filtrated through glomerulus completely, reabsorbed by tubulus and then degraded Concentration in serum or plasma is determined by GFR。
Crude urine ：即肾小球滤过液,120-160ml/min 影响因素：

renal blood flow effective filtration pressure Filtration area membrane permeability
Renal Clearance Rate 肾清除率 肾小球滤过率（GFR)：单位时间内（分钟）经 肾小球滤出的血浆量,即单位时间内产生的原尿 量 正常值： 120-160ml/min
• 肾性 • 肾前性 • 肾后性
衰竭期Failure stage 尿毒症期Uremia Stage：综合症候群，“尿潴留在血中” 而引起的中毒
Related concepts Common symptoms of AFR
LOGO
少尿期oliguria stage：
• Oliguria or anuria, Hematuria, Proteinuria and some kinds of casts • Water intoxication • Hyperpotassemia • Metabolic acidosis • Azotemia
• Compensatory stage: Scr<178μmol/L
• Decompensatory stage: Scr>178μmol/L
• Failure stage: Scr>445μmol/L
•Acute renal failure
Failure
LOGO
Decompensatory
Compensatory
Tubule: reabsorption and acidification
Imaging Examination Immunological test
When and for What Kidney diseases or injuries
LOGO
Overall checkup
Kidney function assessment with other diseases
Diabetes mellitus
Hypertension
Shock or extensive burn
Auto-immunological diseases Drug toxicity
Blood urea nitrogen, BUN
Influence factors Protein intake Protein degradation Liver function
Urea or ornithine cycle in liver
LOGO
Glomerular filtration
EPO (erythropoietin):RBC product 1,25(OH)2 D3: Calcium and phosphorus renin: bood pressure regulation
Related concepts 急性肾衰AFR
LOGO
肾前性Pre-renal：休克早期、大面积烧伤、脱 水等 功能性 肾性 renal：器质性
compensatory：>50ml/min
• <10 replacement therapy
decompensatory： 20-50ml/min
failure： 10-19ml/min uremia： <10ml/min
Serum Creatinine, Scr
血肌酐测定
LOGO
肌肉活动稳定、外源性肌酐来源不变的情况下， Scr浓度主要取决于肾小球的滤过能力。 Normal Value:
• 肾小管上皮细胞坏死 • 肾脏本身：肾小球肾炎、肾盂肾炎、狼疮肾炎 • 肾动脉血栓、栓塞
肾后性post renal：结石、肿瘤、前列腺肥大等 尿路梗阻
Related concepts
Stages for renal failure：
LOGO
代偿期compensatory stage
失代偿期decompensatory stage : 氮质血症Azotemia：血中尿素氮BUN或肌酐sCR超出正 常范围
LOGO
肾清除率：指在单位时间（min）内，肾脏能将 多少毫升血浆中含有的某种物质全部加以清除， 结果以ml/min表示 常用：菊粉清除率、内生肌酐清除率来反映肾小 球滤过率
Endogenous Creatinine
肌肉活动中肌酸 代谢产物 内源性肌酐
LOGO
肌 酐
外源性肌酐
来自于鱼类、肉类 等食物和咖啡、茶 等饮料
Serum or Plasma Cr:
male:53-106μmol/L female:44-97μmol/L
Clinical Significance of Scr increase Glomerular Filtration Injury
LOGO
Chronic renal failure
Sensitive for kidney injury
GFR<50%时 Ccr≈50ml/min
LOGO
For treatment
•30-40: limited protein diets
diuretic • <30 diuretic: not available
Estimate the stage of renal failure
Endogenous Creatinine Clearance Rate, Ccr
Definition：Ccr is the volume of blood plasma with
LOGO
creatinine that is cleared by kidneys per unit time.
即：单位时间内,肾脏可全部清除多少毫升血浆中的内生 肌酐 计算公式：
多尿期polyuria stage
恢复期recovery stage
Related concepts
LOGO
Common symptoms of CFR
Early stage：
• polyuria, Nocturia, Hematuria, Proteinuria and some kinds of casts • Azotemia
• Water intoxication
• Metabolic acidosis (moderate) • Hypopotassemia
Late stage: as above, Uremia, hyperpotassemia,
hypertension, Osteodystrophy, anemia, bleeding tendency……
Tests of glomerular function
肾小球功能检查
——肾小球滤过功能
Tests of Glomerular Function Glomerular Filtration Rate, GFR
LOGO
Endogenous Creatinine Clearance Rate, Ccr
Clinical Significance of Scr increase
LOGO
Differential diagnosis of prerenal and renal azotemia
Prerenal oliguria: Scr<200μmol/L Renal oliguria: Scr>200μmol/L
Normal value: Adults: 3.2-7.1mmol/L Children or infants:
1.8-6.5mmol/L
Clinical Significance
LOGO
Renal damage:
Acute renal failure
Compensatory
Clinical Significance
Clinical Significance
LOGO
wk.baidu.com
Excessive intake of protein and proteolysis:
High protein diet，
High fever, Upper gastrointestinal hemorrhage, extensive burn，severe trauma, hyperthyroidism
prerenal azotemia
Renal failure:
BUN/Cr变化不大
Stage of kidney impairement
LOGO
Ccr
（ml/min)
Scr BUN
(umol/L) (mmol/L)
Compensatory stage
Decompensatory stage Renal failure end-stage renal failure (uremia)
Renal Function Test
肾功能检查 p349
Kidney diseases
Urine tests: urinalysis and others
LOGO
Cheap and convenient;
For screening and following Renal biopsy Renal functions Glomerulus: filtration