Cerebellar ataxia in Hypothyroidism
EDITOR-I read with interest the case report by Krishnan,et
al(1)describing a rather unusual manifestation of
hypothyroidism.Hypothyroidism is a common endocrine disorder but patients
with severe hypothyroidism can present with unusual manifestations(2) and
the authors mentioned about cerebellar ataxia as a presenting syndrome(1).
Acquired cerebellar ataxia has been described in hypothyroidism and is
typically reversible by thyroid replacement therapy(3,4).Cerebellar
degeneration in hypothyroidism with raised antithyroid antibodies is
thought to be immune mediated(3).
I describe a male 54-years old patient who presented recently with a few
weeks' history of dysarthria and severe limb and truncal ataxia.He also
had horizintal nystagmus.There was no other motor or sensory nerological
findings.There was no past history of cerebrovascular (CVA)episodes but he
had history of coronary artery disease(CAD).A possible CVA in the vertebro
-basilar territory or a posterior cranial fossa lesion was suspected.A CT-
brain scan was normal.His echocardiogram and carotid vascular studies were
both normal.All his baseline investigations were normal.MR-brain scan also
failed to show any posterior fossa pathology and both cerebellam were
healthy.A thyroid function test(TFT) showed a free T4 of 2.5pmol/L and his
TSH was >35mu/L.as there was no other explanation for his cerebellar
signs it was a reasonable assumption that his ataxia was 'hypothyroidism'
induced.He was started on thyroxine replacement with careful monitoring of
his TFT and dose adjustment,as he had history of CAD.His improvement has
been slow so far.He is receiving physiotherapy at the stroke unit of this
hospital at the moment.
It is interesting to note that one of six patients in a 1960 paper on
"Cerebellar syndrome in myxoedema" was subsequently found to have
adenocarcinoma(5).I do not suspect that my patient has any such disorder.
1.Krishnan STM,Philipose Z,Rayman G. Hypothyroidism mimicking intra-
abdominal malignancy. BMJ 2002;325:946-47.
2.Westphal SA. Unusual presentations of hypothyroidism. Am J Med Sci
3.Gentilini M,Palmieri M. Myxedematous cerebellar ataxia.Description of a
case. Riv Patol Nerv Ment 1984;105:75-80.
4.Selim M,Drachman DA. Ataxia associated with Hashimoto's disease:
progressive non-familial adult onset cerebellar degeneration with
autoimmune thyroiditis. J Neurol Neurosurg Psychiatry 2001;71:81-87.
5.Quinn N,Barnard RO,Kelley RE. Cerebellar syndrome in myxoedema
revisited: a published case with carcinomatosis and multiple system
atrophy at necropsy. J Neurol Neurosurg Psychiatry 1992;55:616-18.
The patient whose case is described has given his signed informed consent to publication of his case.
Competing interests: No competing interests