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Pregnancy outcome in a patient with Gitelman’s syndrome-a case study
Dr. Gabriel Onyeka Ekekwe, Mrs. Sandhya Rao
St Helens & Knowsley Teaching Hospitals NHS
Whiston Hospital, Warrington Road, Prescot, L35 5DR
Introduction
Gitelman’s syndrome is a rare autosomal recessive
renal tubulopathy
It was first described by Gitelman in 1966 (RiveiraMunoz et al, 2007)
 It is caused by mutation in SLC12A3 gene that
encodes thiazide-sensitive sodium chloride cotransporter in the distant convoluted tubules (Adam et al,
2011; Hollenberg, 2011)
It is characterised by hypokalaemia,
hypomagnesaemia, secondary hyperaldosteronism,
metabolic alkalosis and hypocalciuria
It usually manifests in adolescent or adulthood and are
often asymptomatic.
It may present with muscle weakness/pain, fatigue,
dizziness, nocturia, polydipsia, polyuria, paraesthesia,
palpitations, low blood pressure, and rarely blurring of
vision, vertigo, ataxia, tetany and seizure (Riveira-Munoz
et al, 2007)
The case report presented highlighted the following;
i. Management issues regarding Gitelman’s syndrome
in pregnancy
ii. Areas of controversy in the management of this rare
condition. Only 12 cases has been described in the
literatures (Adam et al, 2011)
iii. The need for high index of suspicion in making the
diagnosis in pregnancy and also early initiation of
appropriate management in order to avoid
morbidities and possibly mortality
Case Report
23 year old G2P1 whose first pregnancy was in 2007
It was complicated with hypokalemia which was
attributed to poor diet and recurrent urinary tract infection
She was managed with oral potassium and magnesium
supplements and long term antibiotic
Had vaginal delivery at 37 weeks following induction of
labour due to pre-eclampsia
Was admitted to the coronary unit with severe chest
pain at 12 weeks gestation in her second pregnancy
She was found to have low potassium (3.1mmol/L),
urinary potassium and calcium were high. ECG did show
any changes
There no history of diarrhoea , vomiting or laxative use
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Diagnosis of heterozygous Gitelman,s syndrome was
made via genetic testing at 24 weeks gestation
She was managed with potassium and magnesium
supplements, amiloride with favourable pregnancy out
come
Had serial growth USS which showed normal fetal
growth and liquor volume
She was admitted on three different occasions and
treated with intravenous potassium when serum
potassium was found to 2.4mmol/L on each occasions
She was induced at 37 weeks due to persistently
potassium
Had an uneventful vaginal delivery of a health baby
She was co-managed with physicians-Nephrologist and
Endocrinologist
Was commenced on Microgynon for contraception 3
months post delivery
The OCP was however discontinued on the advice of
the endocrinologist as it worsened the salt losing
condition
Discussions
Normal pregnancy is associated with up to 70% and
50% increase in renal blood flow and glomerular filtration
respectively (Bennett and Williamson, 2010)
Compensatory increase in tubular reabsorption maintain
maternal electrolytes despite the increase in renal blood
flow and glomerular filtration in pregnancy (Bennett and
Williamson, 2010)
This compensatory mechanism is disrupted in patients
with Gitelman’s syndrome
Therefore, pregnancy and use of combined oral
contraceptive are capable of worsening electrolyte loss as
was noted in our patient (Kwan and Falk, 2010)
Diagnosis can be made with serum potassium and
magnesium, and urinary potassium and calcium. Genetic
testing remains the gold standard for definitive diagnosis
Over a 100 mutations are scattered through SLC12A3
gene. Heterozygous individuals are not expected to be
symptomatic in a recessively transmitted disease
(Reveira-Munoz et al, 2007; Hollenberg, 2011)
Our patient was heterozygous yet symptomatic. This
may be explained by limitation of current genetic tests to
identify the second mutant allele (Reveira-Munoz et al,
2007; Hollenberg, 2011
Wide variation in patients symptoms may due to
genotype-phenotype correlation (Reveira-Munoz, 2007)
Treatment with potassium and magnesium
supplements, and potassium sparing diuretics like
amiloride and spironolactone should be aimed mainly at
symptomatic control rather than aggressive efforts to
normalise potassium and magnesium levels (Kwan and
Falk, 2010; McCarthy et al, 2010)
Spironolactone found to be safe despite concerns of
possible antiandrogenic effects on male fetus (De Arriba
et al, 2009; Basu et al, 2004)
Use of aldosterone antagonist is controversial and
should be reserved as second line diuretic (De Arriba et
al, 2009; Basu et al, 2004)
 Ultrasonic fetal and amniotic fluid surveillance is
mandatory due possible adverse effects of the use of
diuretics in pregnancy
Conclusions
The diagnosis and appropriate management Gitelman’s
syndrome in pregnancy is vital as pregnancy is capable of
worsening the condition
Also it constitutes significant general anaesthetic risk
Despite the exacerbation of the condition in pregnancy,
maternal and fetal outcomes remain favourable
Treatment with potassium and magnesium supplements
and potassium sparing diuretic are aimed at relieving
worsening maternal symptoms
Use of aldosterone antagonist in pregnancy remains
controversial. It may be used as second line drug in
patients intolerant to amiloride or spironolactone (first line
drugs)
Ultrasonic fetal and amniotic fluid surveillance is
mandatory
Combined oral contraceptive should be avoided in these
patients
There need for more research to improve genetic
testing methods for the syndrome .
Research should also be conducted to correlate
Gitelman’s genotypes with maternal and fetal outcome
References
Adam, M., Panitz, B. and Adam, B (2011) ‘Eplerenone
for Gitelman Syndrome in Pregnancy’, Nephrology vol.
16; pp. 349-350. Available from: doi: 10.1111/j.14401797.2010.01396.x
Basu, A., Dillion, R.D.S., Taylor, R., Davison, J.M. and
Marshall, S.M. (2004) ‘Is normalisation of serum
potassium and magnesium always necessary in
Gitelman’s Syndrome for a successful obstetric outcome?
International Journal of Obstetrics and Gynaecology vol.
111: pp. 630-634.
Bennett, P. and Williamson, C. (2010) ‘Basic Science in
Obstetrics and Gynaecology-A textbook for MRCOG Part
1, 4th edition. London: Churchill Livingstone.
De Arriba, G., Sanchez-Heras, M. and Basterrechea,
M.A. (2009) ‘Gitelman’s Syndrome during pregnancy: a
therapeutic challenge’, Arch. Gynecol Obstet. 280:807809 Available from: doi: 10.1007/s00404-009-0994-3
Hollenberg, N.K. (2011) ‘Improving genetic testing for
Gitelman’s syndrome’, Curr. Hypertens Rep [Online]
Available from: doi: 10.1007/s11906-011-0213-z
Kwan, T.K. and Falk, M.C. (2010) ‘Second pregnancy
outcome in a patient with Gitelman syndrome without the
use of parenteral electrolyte supplementation’, The Royal
Australian and New Zealand College of Obstetricians and
Gynaecologists vol. 51; pp. 91-95 Available from:
doi:10.1111/j.1479-828X.2010.01248.x
McCarthy, F.P., Magee, C.N., Plant, W.D. and Kenny,
L.C. (2010) ‘Gitelman’s syndrome in pregnancy: case
report and review of the literature’, Nephrol. Dial.
Transplant, vol. 25:1338-1340 Available from: doi:
10.1093//ndt/gfp688
Riveira-Munoz, E., Chang, Q., Bindels, R.J. and
Devuyst, O. (2007) ‘Gitelman’s syndrome: towards
genotype-phenotype correlations? Padiatr. Nephrol. Vol.
22:326-332 Available from: doi: 10.1007/s00467-0060321-1