Transcript Polyuria-polydipsia Central diabetes insipidus Nephrogenic diabetes insipidus Psychogenic water drinking

Polyuria-polydipsia
Central diabetes insipidus
Nephrogenic diabetes insipidus
Psychogenic water drinking
Diabetes mellitus
Survey of diabetes insipidus
History
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quantitation of daily fluid intake and
output
 noturia or enuresis
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detailed dietary history
 avoid foods with a high protein content
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acuteness of onset
drug
growth and development
Survey of diabetes insipidus
Lab
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24h I/O
Urine: specific gravity or osmo., glucose
Serum sodium and osmo.
definite diagnosis: water deprivation test
Water deprivation test
Prcedure
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morning: empty bladder & weigh pt
NPO
blood: Na, K, Ca, Crea, osmo., vasopressin
q1h check:
 BW
 Urine: vol. , specific gravity(sg), osmolality
 Serum: Na, osmolality
Water deprivation test
Ending (one of following)
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BW  > 3%
serum Na > 150mmol/L or osmo. > 300 mmol/L
Uosmo reaches 850 mmol/kg for 2 consecutive tests
Uosmo stablized ( < 30mmol/kg between the last 2
collections)
Empty bladder
Blood: osmo., Na, and vasopressin
DDAVP (2ug) s.c. or 10ug (0.1 ml) intranasal,
and drink as desired
Uosmo and Sosmo q30min x 2, (x4 if intranasal)
Interpretation
Normal response
Uosmo  to 500 – 1400 mosm/kg
U/O decrease
Sosmo: in normal range (< 295 mmol/kg)
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 U/P ratio > 2
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ADH: no increase in Uosmo and no decreased
U/O
DI
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Uosmo: no increase, U/O: no decrease
Sosmo increases (U/S ration < 2)
ADH: CDI: U/O decrease, Uosmo increase
NDI: no response
BW Urine
Serum
Volume
Specific
gravity
Osomlarity Na
Osmolarity
Hr 0
Hr 1
Goal
13.5
50
<1.005
255
152
310
13.4
40
1.005
258
155
311
150
305
Hr’0
13.4
3%
Hr’0.5 13.8 50
13.8
Hr’1
Hr’1.5 13.8 30
311
<1.005
234
317
319
524
314
Interpretation
Max
Uosm/Sosm
before DDAVP
Max
Uosm s/p
Uosm/Sosm s/p DDAVP
DDAVP
Normal or
PWD
Partial CDI
>1
>1
< 9%
>1
>1
> 9%
Complete
CDI
<1
< or >1
> 50%
NDI
<1
<1
< 45%
Patient
0.82
1.66
123%
Central diabetes insipidus
Cause
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brain tumor
idiopathic
neurosurgery
head trauma
HIE
histiocytosis
Survey: skull x-ray or head CT
Tx: hormonal replacement
Nephrogenic diabetes
insipidus
Cause
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congenital
acquired: chronic renal Dz
e- disorder: hypokalemia, hypercalcemia
sickle cell trait
adrenal insufficiency
drug
 lithiium, colchicine, constrast, diuretics
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diet
 protein starvation, chronic salt depletion, chronic high
water intake
Nephrogenic diabetes
insipidus
Survey
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electrolyte
renal echo
Treatment
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low sodium diet (< 1mmol/kg/24h)
adequate protein (2g/kg/day)
300-400 ml/kg water
drug:
 thiazide (hydrochlorothiazide 2-4mg/kg/d):注意
hypokalemia, 可與 amiloride併用
 indocin (2mg/kg/d):亦可與 thiazide併用
Water deprivation test
Prcedure




morning: empty bladder & weigh pt
NPO
blood: Na, K, Ca, Crea, osmo., vasopressin
q1h check:
 BW
 Urine: vol. , specific gravity(sg), osmolality
 Serum: Na, osmolality
Water deprivation test
Ending (one of following)

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BW  > 5% (or 3%)
serum Na > 150mmol/L and plasma osmo. > 305
mmol/kg
Uosmo reaches 850 mmol/kg for 2 consecutive
tests
Uosmo stablized ( < 30mmol/kg between the last
2 collections)
Empty bladder
Blood: osmo., Na, and vasopressin

DDAVP (2ug) use, and drink as desired
Uosmo and Sosmo q30min x 2