Kleta R, Candan B, Tanja F, Stefan F, et al
Physiologic treatment of Bartter syndrome
Am Soc Nephrol Ann Mtg -- Toronto
J Am Soc Nephrol
(Sep) 11:107A 2000

Bartter syndrome (BS) is a major reason of congenital renal
saltwasting. Even though BS was revealed as being caused by a hindered
NaCl reabsorption in the thick ascending limb of Henle's loop, current
treatment options do not take these findings into account.
Therefore,
we treated a 7 year old boy with BS type III with a balanced NaCl diet.
The idea was to suppress the elevated aldosterone and thereby to reduce
the renal potassium loss. The treatment consisted of the administration of
a high-salt containing mineral water (NaCl content 180 mmol / l). The
urinary excretion rates of Na+, K+, aldosterone-18-glucuronide (A-18-G),
and creatinine were measured by 24 hours specimens. By simultaneous serum
measurements urinary fractional excretion rates for Na+ (FeNa) and K+
(FeK) were determined.
The elevated FeNa after starting the NaCl diet
indicates an adequate salt supply. BS patients exhibit furosemide treated
signs, therefore the FeNa has to become pathologic. As a result of the
adequate salt supply A-18-G became normal, FeK was lowered markedly. The
elevated and not changing renin concentration indicates part of the
pathophysiology, because the renin producing macula densa is also affected
by either NKCC2, ROMK, or (in this case) ClC-Kb mutations which result in
elevated renin.
In summary, we suggest to give BS patients a (high)
NaCl diet which should result in an elevated FeNa.
|
before NaCL diet |
after NaCl diet |
ref. values |
K+ supply |
9 |
6 |
1 mmol/kg die |
NaCl supply |
ad libitum |
9 |
3 mmol/kg die |
serum K+ |
3.4 |
3.8 |
3.5-5.0 mmol/l |
FeNa |
0.5 |
3.5 |
< 1 % |
FeK |
500 |
60 |
15+/-10 % |
A-18-G |
17.7 |
4.1 |
< 8 mg/die |
Renin |
145 |
144 |
< 50 mU/ml |
Copyright 2000, American Society
of Nephrology