0-30 Flashcards
Urine formation
URINE FORMATION:
**1) GLOMERULAR FILTRATION **
Result:isotonic filtered, protein-free
(this happens in GLOMERULUS)
2) PROXIMAL TUBULAR REABSORPTION
Result: 1/3 of the Glomerular filtrate
[Na] equal to plasma
Zero glucose or amino acids
3) HENLE’S LOOP
Result: hypotonic fluid, hipoosmic
10% of Glomerular filtrate
4) DISTAL CONVOLUTED TUBULE
uptake of Na + on aldosterone secretion of protons, ammonia and potassium
5) DUCT SYSTEM MANIFOLDS
Under the influence of ADH regulates osmolarity
Endocrinal function of kidney
ENDOCRINE FUNCTION
ERYTHROPOIETIN
Endothelial peritubular cells
proximal convoluted tubule
** DIHYDROXYCHOLECALCIFEROL 1.25
PROSTAGLANDINS**
KININS
Renin-angiotensin-aldosterone? (RAAS)
Metabolic kidney function
METABOLIC FUNCTION
E.g. gluconeogenesis, hormone degradation
what do you have to pay atttention to while examining a patient?
- HISTORY
- URINARY SIGNS AND SYMPTOMS
- MEASUREMENT OF RENAL FUNCTIONS
- URINALYSIS
- PHYSICAL EXAMINATION
- INSTRUMENTAL DIAGNOSTICS
Clinical history of nephrological patient
CLINICAL HISTORY
• Age, sex
• Places of residence
- Employment
- Life habits
- Power Supply
- Alcohol
- Smoke
What to pay attention to clinical history?
CLINICAL HISTORY
Evidence of an earlier kidney disease
• Elevated creatinine and Bun in the past
• Proteinuria, hematuria, dark urine, oedema, IVU
• History of Hypertension
• History of diabetes mellitus
• Signs and symptoms of the urinary tract
• Oliguria, polyuria, nocturia
• Collagen diseases: lupus, Scleroderma, Wegener, S-H
• History of hereditary kidney disease: polycystic kidney disease, AlportSyndrome
• Tumours, Amyloidosis
Clinical medication history
CLINICAL Medication HISTORY
• NSAID’s
• Penicillin
• Aminoglycosides
• Drug abuse
• Exposure to heavy metals: lead, cadmium, gold
• Medicines that cause worsening of renal function: ACE-I (angiotensin converted enzyme inhibitor), contrast media
Signs and symptoms for nefrology patients
SIGNS AND SYMPTOMS
GENERAL: EDEMA, FEVER
URINARY CALCULI:
1) ANOMALIES of URINARY VOLUME
2) URINARY ABNORMALITIES (e.g. MACROSCOPIC URINE)
3) PAIN and COLIC
4) DISORDERS of URINATION
Anuria, oliguria, polyuria
Anuria/Oliguria-Polyuria
Normal Urinary volume: 1 ml/min
ANURIA: 100 ml/24 < hours
OLIGURIA: 100-400 ml/24 hours
POLYURIA > 2500 ml/ 24 hours
what is:
Dysuria
pollakiuria
polyuria
nocturia
- *Dysuria** = difficulty urinating
- *Pollakiuria** = increased urination frequency
- *Polyuria** = increase volume
- *Nocturia** = increased and / or prevailing nighttime urination
Renal plasma flow
glomerular filtration rate
Renal plasma flow (RPF):
600 ml / min
Glomerular filtration rate (GFR): 125 ml / min x 1.75 m2 body surface area
Clearance, formula, definition
CLEARANCE = UXV / P
Where U = urinary concentration in mg / dl
P = plasma concentration in mg / dl
V = urine volume in ml / min
it is THE QUANTITY OF BLOOD THAT IS PURIFIED DATE SUBSTANCE IN UNITY OF TIME
How to measure GFR,
For the measurement of Glomerular filtration rate (GFR) using the CLEARANCE Of INSULIN
Molecular weight substance “ESOGENA 5000”
A substance completely filtered, not reabsorbed nor secreted by the tubules.
Shrinks in old age
Creatinine clearance
what it is, where secreted, how much secreted
CREATININE CLEARANCE
For clinical purposes you can use the creatinine clearance
ENDOGENOUS substance
originating from muscle creatine and phosphocreatine
Filtered and secreted distal level (10-30)
In urine 20 mg/kg/day in females,
22 in adult males
123 ± 20 ml/min per 1.73 m2 in males 114 ± 6 ml/min per 1.73 m2 in female
Assesment of GFR
Assessment of GFR
CREATININE: The assumption is that in an individual production and renal excretion of creatinine is constant in 24h.
 • Easy and widespread use in routine diagnostics.
• It should be used the enzymatic method, much more accurate alkaline picrate.
Creatininemia
creatinine
In the male 0.90-1.20 mg / dl
In the female 0.80-1.00 mg / dl
In the newborn 0.30 mg / dl
At 10 years 0.55 mg / dl
GFT formulas, best, not used, etc.
Assessment of GFR
FORMULAS
• method of Cockroft-Gault
(best in the IRC Advanced; tends to be obsolete)
(140- age) x weight (kg): 72 x serum creatinine (mg / dl) x 85% in women
• MDRD equation (best in advanced stages in the IRC)
** CKD-EPI Calculator**
(it is the most current, is indicated in the early stages of the IRC).
Renal clearance & GFT direct and indirect studies,
advantages and disadvantages
Renal clearance & GFR
direct
studies of clearance of exogenous substances (inulin, iohexol, iotamato, Cr51-EDTA)
studies of the clearance of endogenous substances (Ex. Creatinine)
indirect
GFR estimation by anthropometric parameters, anthropological and biochemical
advantages and disadvantages
(varnele) accurate, but
(iksiukas) expensive, long and not applicable to screening
(iksiukas) requires both blood and urine and a racoolta accurate and timed urine
(varnele) very simple and convenient
? accuracy
BUN, UREA
UREA
UREA = CO(NH)2 PM 60
AZOTEMIA O UREA: 20 – 40 mg/dl
BUN = Blood Urea Nitrogen (Urea Nitrogen): 8–21 mg/dl
BUN
Divide by 2.14 (2 atoms of nitrogen) 60:28 = 2.14
BUN with azotemia multiplies by 2.146
The origin, path of urea
UREA
Urea originates in the liver from amino acids from muscle tissue from the stomach, the intestines (Krebs-Henseleit cycle)
Urea enters the blood, a part is lost due to extrarenale (e.g. feces, intestinalgases, sweat < of 2 g/day)
The rest get to the kidney where it is filtered and reabsorbed
Urea, clearance, GFR
UREA
• THE CLEARANCE OF UREA IS APPROXIMATELY HALF THAT OF CREATININE
• MAKE AN AVERAGE BETWEEN THE TWO WHEN THE GFR IS REDUCED
(THAT’S THE CREATININE IS SECRETED, UREA IS REABSORBED)
By what UREA and creatinine is influenced
UREA is influenced by diet, state of hydration, from catabolism (treatment with diuretics, corticosteroids), intestinal bleeding, liver function
CREATININE is influenced by diet, but it is + constant, and muscle mass, as well as gender and age
Fraction of Filtration
Fraction of Filtration
GFR: renal plasma flow
125: 654 = 0,192 = 19 X 100
from 654 ml of plasma are formed 125 ml of filtrate that is, 19.2%,
normal values 16-22% increases in heart failure: reduces multiple renal flow that the filtrate
Urianalysis
The URINALYSIS urine first issued in the morning
MACROSCOPIC EXAMINATION
PHYSICAL TRAITS: APPEARANCE, SMELL, COLOUR
CHEMICAL CHARACTERISTICS: pH, specific gravity, osmolality, glucose, proteinuria, ketones, bilirubin, urobilinogen, nitrite, leukocytes
Or sediment MICROSCOPIC EXAMINATION: red blood cells, leukocytes,epithelial cells, cylinders, microbial flora, crystals, fungi
