Transcript Urea 21.6 mmol/l

Week 2: PBL 2
Manuel van Deventer
Week 2: PBL 2
Sosobala Mkhize, a forty year old widower who works
as a herbalist, is brought into casualty by his
daughter. She says that he had been suffering from a
white painful plaque in his mouth for three weeks and
that he had just returned from a one week visit to his
homeland in search for medicinal herbs. Over the
past three days he had not eaten anything and drank
only a small amount of fluid, this morning, when she
went to take him to his shop, she found him weak and
unable to coherently explain what was happening. On
admission he was intermittently confused. His blood
pressure was found to be low and an IV saline was
commenced. On catheterisation of his bladder, very
little urine was drained.
Personal Details
•
•
•
•
Name:
Age:
Marital Status:
Resident:
Sosobala Mkhize
40
Widower
Umzinto, Kwazulu Natal
Social History
• Mr Mkhize is herbalist.
• Since his wife died he has lived with his
daughter in a small town in the KwaZulu
Natal
• He is independent in all activities.
• Smoked up until the age of 30.
• Drinks 3 or 4 beers per week.
Past Medical History
• No prior history of renal disease
• No previous history of confusion or
memory loss
Current Rx
• Possibly self-medicates with herbal
remedies
General Examination
 White Plaque
 Confused, disoriented
 Dry mouth, flaccid skin
CVS
• Blood Pressure: 90/50 lying;
• Pulse rate: 115/minute
• Jugular venous pressure was not raised
with the patient lying flat
• CVS examination otherwise normal
Abdomen/UroGenital
•
•
•
•
•
Bowel sounds present.
No organomegaly or masses
No bladder palpable
Urinalysis: Oliguric
Catheterisation produced a small amount
of urine
Investigations
FULL BLOOD COUNT & PLATELETS
White Cell Count
Red Cell Count
Haemoglobin
Haematocrit
MCV
MCH
MCHC
Red Cell Distribution Width
Platelets
Mean Platelet Volume
9.7
5.9
12.5
0.54
86.3
29
33.7
13.6
156
10.2
x 109 / ℓ
x 1012 / ℓ
g / dℓ
ℓ/ℓ
fℓ
pg
g/dℓ
%
x 109 / ℓ
fℓ
Reference Ranges
4.00
4.89
14.3
0.43
79.1
27
32
11.6
137
7.0
- 10.00
- 6.11
- 18.3
- 0.55
- 98.9
- 32
- 36
- 14
- 373
- 11.4
Investigations
BIOCHEMISTRY
Sodium
Potassium
Chloride
Total CO2
Urea
Creatinine
Phosphate
Magnesium
Total Protein
Albumin
Creatine Kinase
Glucose
HIV
Reference Ranges
135
6.6
101
13
21.6
770
1.6
0.8
112
28
96
3.2
Pos
mmol / ℓ
mmol / ℓ
mmol / ℓ
mmol / ℓ
mmol / ℓ
μmol / ℓ
mmol / ℓ
mmol / ℓ
g/ℓ
g/ℓ
U/ ℓ
mmol/l
135
3.3
99
18
2.6
60
0.8
0.65
60
35
25
4.1
-
147
5.3
113
29
7.0
120
1.4
1.1
85
52
195
5.6
Investigations
URINE BIOCHEMISTRY
Urine Volume
Urine Sodium
Urine Osmolality
Urine Creatinine
Urinary Myoglobin
300
60
260
20
negative
ml/24h
mmol / ℓ
mOsmol/Kg
mmol/l
Is this Acute / Chronic
Pre-Renal / Intrinsic
Prerenal
Urea/Creat > 75
U-Na < 10mmol/l
FeNa < 1 %
Urine:plasma Osmol
> 1.3
ATN
Urea/Creat < 75
U-Na > 20 mmol/l
FeNa > 1 %
Urine:plasma Osmo
< 1.3
Urea / Creatinine
• Urea: 21.6 mmol/l
• Creatinine: 770 μmol/l
Urea
= 21.6 mmol/l
Creatinine
0.770 mmol/l
=
28
ATN
Urea
Protein
Distal Tubule
Glomerulus
Amino acids
Proximal Tubule
NH3
Urea
Cambamoyl
phosphatase
Ornithine
Arginine
Urea cycle
Citruline
Aspartat
e
40-60 %
Arginosuccinate
Collecting duct
Creatinine
Creatine Kinase
Creatine
Phosphocreatine
ATP
ADP
Creatinine
U-Na
• 60 mmol/l
ATN
Fe-Na
FeNa =
FeNa =
Urine [Na]
--------------
Plasma [Na]
60
--------------
FeNa = 1.7
135
X
X
Plasma [Cr]
---------------
Urine [Cr]
0.770
---------------
20
ATN
X
100
X
100
Osmolality
• Measured Osmolality
– Freezing point depression
• Calculated Osmolality
– 2 Na + Urea + Glucose
= 2(135) + 22 + 3
= 295
Osmolality
• U-Osmolality = 260
• = 260/295 = 0.88
• Also U Osmo < 350
ATN
U-Microscopy
• Increased renal tubular cells and
ATN
granular casts
Etiology of ATN in this
patient
Electrolyte abnormalities
↑ Potassium
K+
redistribution
Pseudo
hyperkalaemia
Hemolysis
Acidosis
K+
retention
↓ K+ excretion
Thrombocytosis
Dehydration
↓ Mineralo
corticoids
Leukocytosis
Massive
tissue Hypoxia
Addison’s
ACE inhibitors
Insulin
deficiency
Rhabdomyolysis
K+ sparing
diuretics
Amiloride
Spironolactone
↑ Potassium
High Anion Gap
Metabolic Acidosis
Normal Anion Gap
Metabolic Acidosis
DKA
↓ mineralocorticoids
Acute renal failure
Obstructive uropathy
Chronic Renal Failure
www.aafp.org/afp/20060115/283.html
↓ Potassium
Normal Anion Gap
Metabolic Acidosis
Metabolic Alkalosis
Diuretic therapy
Diarrhea
Vomiting
RTA
↑ Mineralocorticoids
Anion Gap
Cations = Anions
Cations
• Na+ + K+
–
Anions
Cl- – HCO3-
↑ Unmeasured Anions (Proteins, PO43-, SO42-)
↑ Anion Gap
Anion Gap
135 + 6.6 – 101 – 13 = 27.6 ↑
Anion Gap
•
•
•
•
•
•
•
•
M = Methanol toxicity
U = Ureamia of renal failure
D = Diabetes Mellitus
P = Paraldehyde toxicity
I = Isoniazid / Iron toxicity / Ischemia
L = Lactic acidosis
E = Ethylene glycol toxicity
S = Salicylate toxicity
http://upload.wikimedia.org/wikipedia/commons/a/a2/Renin-angiotensinaldosterone_system.png
↑ Aldosterone
Distal Renal
Tubule
Na+
K+
H+
↓ Aldosterone
Distal Renal
Tubule
Na+
K+
H+
Hyponatraemia
Measure plasma
osmolality
↑ Increased
Normal
↓ Decreased
↑ Increased other
osmotically
active solutes
Pseudohyponatr
aemia
Assess ECF
volume
Increased
Normal
Decreased
Renal loss
Extrarenal loss
SIADH
H20
SIADH
1.
2.
3.
4.
Clinically Euvolemia
Plasma Osmolality < 270 mosmol/kg
Hyponatraemie Na < 130 mmol/l
Exclude
1.
2.
3.
4.
5.
Exclude
1.
2.
6.
7.
Cardiac
Renal
Thyroid
Adrenal
Pituitary surgery
Medication known to stimulate ADH
Urine Osmolality inappropriately high
U-Na > 20 mmol/l
↑ Na+
Hypervolaemia
↑↑ Na+
↑ H20
Hyperaldosteronism
Cushing’s
Hypertonic Saline
Salt Water Ingestion
Euvolaemia
↑ Na+
Diabetes Insipidus
Hypovolaemia
↓ H20
U-Na > 20
U-Na < 10
Osmotic diuresis
GIT Loss and
↓ H20 intake
Diuretic therapy and
↓ H20 intake
TCO2
• Bicarbonate (HCO3)
↓ pH α ↓ HCO3
↓ PCO2
Total Protein
Rx
Prevention
• Fluid management
• Avoid nephrotoxic drugs
Drug Dosaging
• Creatinine Clearance
• = U*V
P
= 20 * 300/24/60
0.77
= 5.4 ml/min
Rx of Complications
Hyperkalaemia
• Exchange resins – Kayexalate 30-60g po
or pr 6hrly
• Insulin and dextrose
• Dialysis
Acidosis
Treated when:
• CO2 <15 and pH <7.2
• Bicarbonate
• Dialysis
Uremia
• Complications of uremia
• What in the history and
investigations of this patient
suggestive of uremia
• Possible indications for dialysis
Fluid Overload
• Aggressive diuresis if still passing urine
• Dialysis if oligoanuric
• Fluid restriction
Indications for dialysis
• Acidosis (severe acidosis resistant to
conservative measures)
• Electrolytes (Hyperkalemia resistant to
conservative measures)
• Intoxication (alcohols and dialyzable
drugs)
• Overload (of fluid)
• Uraemia
Conclusion