Long-term follow-up of patients with Bartter syndrome type I and II.
BACKGROUND
Little information is available on a long-term follow-up in Bartter syndrome type I and II.


METHODS
Clinical presentation, treatment and long-term follow-up (5.0-21, median 11 years) were evaluated in 15 Italian patients with homozygous (n = 7) or compound heterozygous (n = 8) mutations in the SLC12A1 (n = 10) or KCNJ1 (n = 5) genes.


RESULTS
Thirteen new mutations were identified. The 15 children were born pre-term with a normal for gestational age body weight. Medical treatment at the last follow-up control included supplementation with potassium in 13, non-steroidal anti-inflammatory agents in 12 and gastroprotective drugs in five patients. At last follow-up, body weight and height were within normal ranges in the patients. Glomerular filtration rate was <90 mL/min/1.73 m(2) in four patients (one of them with a pathologically increased urinary protein excretion). In three patients, abdominal ultrasound detected gallstones. The group of patients with antenatal Bartter syndrome had a lower renin ratio (P < 0.05) and a higher standard deviation score (SDS) for height (P < 0.05) than a previously studied group of patients with classical Bartter syndrome.


CONCLUSIONS
Patients with Bartter syndrome type I and II tend to present a satisfactory prognosis after a median follow-up of more than 10 years. Gallstones might represent a new complication of antenatal Bartter syndrome.
Puricelli
Elena
E
Department of Pediatrics, San Leopoldo Mandic Hospital, Largo Mandic 1, Merate, Lecco, Italy.
Bettinelli
Alberto
A
Borsa
Nicolò
N
Sironi
Francesca
F
Mattiello
Camilla
C
Tammaro
Fabiana
F
Tedeschi
Silvana
S
Bianchetti
Mario G
MG
D001477:Bartter Syndrome / Q000145:classification / Q000188:drug therapy / Q000235:genetics*; D001827:Body Height; D001835:Body Weight; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009154:Mutation / Q000235:genetics*; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics*; D011379:Prognosis; D028021:Sodium-Potassium-Chloride Symporters / Q000235:genetics*; D064466:Solute Carrier Family 12, Member 1; D013997:Time Factors
C086989:KCNJ1 protein, human; D024661:Potassium Channels, Inwardly Rectifying; C578714:SLC12A1 protein, human; D028021:Sodium-Potassium-Chloride Symporters; D064466:Solute Carrier Family 12, Member 1