Thyroid crisis

Emergency Medicine

Clinicals - History

Fact Explanation
History of hyperthyroidism The thyroid crisis typically occurs in
patients in whom preexisting hyperthyroidism
has not been diagnosed or has been
treated insufficiently.Thyroid crisis has been reported to be precipitated by the discontinuation of antithyroid drugs. It is the highest triggering factor for thyroid crisis. This is a life-threatening condition requiring emergency treatment.Graves Disease remains the most common cause of t thyroid crisis. However, toxic multinodular goitre and toxic adenoma may also progress to a thyroid crisis.
History of hyperthyroidism
The thyroid crisis typically occurs in
patients in whom preexisting hyperthyroidism
has not been diagnosed or has been
treated insufficiently.Thyroid crisis has been reported to be precipitated by the discontinuation of antithyroid drugs. It is the highest triggering factor for thyroid crisis. This is a life-threatening condition requiring emergency treatment.Graves Disease remains the most common cause of t thyroid crisis. However, toxic multinodular goitre and toxic adenoma may also progress to a thyroid crisis.
Hyperpyrexia Body temperature can rise up to 41° centigrade. Occurs due to concomitant sympatho-adrenal
hyperactivity.
Hyperpyrexia
Body temperature can rise up to 41° centigrade. Occurs due to concomitant sympatho-adrenal
hyperactivity.
History of physical or emotional stress This includes: trauma, surgery, burn, myocardial infarction or childbirth. The thyroid crisis has an
abrupt onset, and is almost always evoked
by a precipitating factor.
History of physical or emotional stress
This includes: trauma, surgery, burn, myocardial infarction or childbirth. The thyroid crisis has an
abrupt onset, and is almost always evoked
by a precipitating factor.
History of infection Second commonest trigger for thyroid crisis is infection,particularly that of the upper respiratory tract. History of infection
Second commonest trigger for thyroid crisis is infection,particularly that of the upper respiratory tract.
Radio-iodine therapy / Use of iodinated subtance Thyroid crisis may occur within days of radio-iodine therapy, as acute irradiation damage may lead to a transient rise in serum thyroid hormone levels. The use of other iodinated substances can also act as triggers: disinfectants, antiseptics, and iodinated contrast agents. Amiodarone is the drug most often associated with thyroid stimulation. Under physiological conditions, increased serum levels of iodine
results in inhibition of thyroid hormone synthesis and self regulatory inhibition of iodine transportation. Thus, the excess of iodine and absence of a regulatory system can lead to persistent increase in the production
of thyroid hormone and thyroid crisis.
Radio-iodine therapy / Use of iodinated subtance
Thyroid crisis may occur within days of radio-iodine therapy, as acute irradiation damage may lead to a transient rise in serum thyroid hormone levels. The use of other iodinated substances can also act as triggers: disinfectants, antiseptics, and iodinated contrast agents. Amiodarone is the drug most often associated with thyroid stimulation. Under physiological conditions, increased serum levels of iodine
results in inhibition of thyroid hormone synthesis and self regulatory inhibition of iodine transportation. Thus, the excess of iodine and absence of a regulatory system can lead to persistent increase in the production
of thyroid hormone and thyroid crisis.
Diarrhea Thyroid hormone Increases gut motility. There is an increased frequency of bowel movements due to increased motor contraction in the small bowel leads to diarhea. Diarrhea
Thyroid hormone Increases gut motility. There is an increased frequency of bowel movements due to increased motor contraction in the small bowel leads to diarhea.
Palpitation Thyroid hormone Increases heart rate and cardiac output. In addition it increases catecholamine sensitivity and β-adrenergic receptors in the myocardium this results in palpitations. Palpitation
Thyroid hormone Increases heart rate and cardiac output. In addition it increases catecholamine sensitivity and β-adrenergic receptors in the myocardium this results in palpitations.
Neuropsychiatric features Neuropsychiatric manifestations of thyrotoxicosis include emotional lability, restlessness, anxiety, agitation, confusion, psychosis and even coma Neuropsychiatric features
Neuropsychiatric manifestations of thyrotoxicosis include emotional lability, restlessness, anxiety, agitation, confusion, psychosis and even coma
Shortness of breath Shortness of breath may be due to decreased lung compliance, engorged pulmonary capillary bed or left ventricular failure. Respiratory
failure secondary to respiratory muscle
paralysis can cause death in these patients.
Shortness of breath
Shortness of breath may be due to decreased lung compliance, engorged pulmonary capillary bed or left ventricular failure. Respiratory
failure secondary to respiratory muscle
paralysis can cause death in these patients.

Clinicals - Examination

Fact Explanation
Fever Thyroid hormones increase the basal metabolic rate (BMR). This results in greater energy production leading to increased thermogenesis
;perspiration and heat intolerance., Temperature can rise up to 41° centigrade.
Fever
Thyroid hormones increase the basal metabolic rate (BMR). This results in greater energy production leading to increased thermogenesis
;perspiration and heat intolerance., Temperature can rise up to 41° centigrade.
Tachycardia Thyroid hormone increases heart rate and
cardiac output.
Tachycardia
Thyroid hormone increases heart rate and
cardiac output.
Signs of cardiac failure Thyroid crisis is often accompanied by varying
degrees of congestive heart failure. Congestive heart failure may be the initial clinical
presentation in approximately 6% of patients with hyperthyroidism. Dysrhythmias, cardiac failure and respiratory failure secondary to respiratory muscle paralysis are recognized causes of death in these patients.
Signs of cardiac failure
Thyroid crisis is often accompanied by varying
degrees of congestive heart failure. Congestive heart failure may be the initial clinical
presentation in approximately 6% of patients with hyperthyroidism. Dysrhythmias, cardiac failure and respiratory failure secondary to respiratory muscle paralysis are recognized causes of death in these patients.
Atrial Fibrillation In thyroid crisis atrial tachydysrhythmias, occur due to increased catecholamine sensitivity and β-adrenergic receptor numbers in heart. , Atrial Fibrillation
In thyroid crisis atrial tachydysrhythmias, occur due to increased catecholamine sensitivity and β-adrenergic receptor numbers in heart. ,
Wasting A common finding in thyroid crisis is weight loss, despite regardless of the calorie intake. Thermogenesis leads to increased
perspiration and heat intolerance.
In addition thyroid hormones also stimulate lipolysis.
Wasting
A common finding in thyroid crisis is weight loss, despite regardless of the calorie intake. Thermogenesis leads to increased
perspiration and heat intolerance.
In addition thyroid hormones also stimulate lipolysis.
Changes in thyroid gland With Graves’ disease, diffuse enlargement of the gland, and possibly a bruit, caused by increased vascularity and blood flow; can be appreciated. A toxic multi nodular goiter can have physical findings of one or more nodules. In subacute thyroiditis, a tender thyroid gland could be found,
In older individuals, typical symptoms of thyroid crisis may not be apparent.
Older patients may present with some atypical symptoms including weight loss, palpitations, weakness, dizziness, syncope, or memory loss, and physical findings of sinus tachycardia
or atrial fibrillation.
Changes in thyroid gland
With Graves’ disease, diffuse enlargement of the gland, and possibly a bruit, caused by increased vascularity and blood flow; can be appreciated. A toxic multi nodular goiter can have physical findings of one or more nodules. In subacute thyroiditis, a tender thyroid gland could be found,
In older individuals, typical symptoms of thyroid crisis may not be apparent.
Older patients may present with some atypical symptoms including weight loss, palpitations, weakness, dizziness, syncope, or memory loss, and physical findings of sinus tachycardia
or atrial fibrillation.
Jaundice Unexplained jaundice is suggestive of thyroid crisis, but is considered a poor prognostic sign Occurs due to gastrointestinal-hepatic dysfunction in severe hyperthyroidism. Jaundice
Unexplained jaundice is suggestive of thyroid crisis, but is considered a poor prognostic sign Occurs due to gastrointestinal-hepatic dysfunction in severe hyperthyroidism.

Investigations - Diagnosis

Fact Explanation
Triiodothyronine (T3) and L-thyroxine (T4) Since its pathophysiologic mechanisms have
not been clarified, the diagnosis of TS is based on clinical
manifestations, even if the symptoms
and signs may not be specific.low levels of thyroid stimulating hormone
(TSH) and high levels of free triiodothyronine
(T3) and free L-thyroxine (T4)
are characteristic, but as yet stated, not helpful
in distinguishing uncomplicated thyrotoxicosis
from thyroid crisis
Triiodothyronine (T3) and L-thyroxine (T4)
Since its pathophysiologic mechanisms have
not been clarified, the diagnosis of TS is based on clinical
manifestations, even if the symptoms
and signs may not be specific.low levels of thyroid stimulating hormone
(TSH) and high levels of free triiodothyronine
(T3) and free L-thyroxine (T4)
are characteristic, but as yet stated, not helpful
in distinguishing uncomplicated thyrotoxicosis
from thyroid crisis
Thyroid stimulating hormone (TSH) Low levels of thyroid stimulating hormone
(TSH) and high levels of free triiodothyronine
(T3) and free L-thyroxine (T4)
are characteristic of thyroid crisis,
Thyroid stimulating hormone (TSH)
Low levels of thyroid stimulating hormone
(TSH) and high levels of free triiodothyronine
(T3) and free L-thyroxine (T4)
are characteristic of thyroid crisis,
Random Blood sugar The hyperglycemia tends to occur because of
a catecholamine-induced inhibition of insulin release, and increased glycogenolysis
Random Blood sugar
The hyperglycemia tends to occur because of
a catecholamine-induced inhibition of insulin release, and increased glycogenolysis
Serum Electrolytes This will show Hypercalcaemia, which is result of Haemoconcentration
and bone resorption as thyroid hormone increase bone turnover and resorption
Serum Electrolytes
This will show Hypercalcaemia, which is result of Haemoconcentration
and bone resorption as thyroid hormone increase bone turnover and resorption
WBC/DC This will show leukocytosis with left shift as a result of stress response, with or without infection WBC/DC
This will show leukocytosis with left shift as a result of stress response, with or without infection
ECG Electrocardiogram manifestations of thyroid crisis most commonly include
sinus tachycardia and atrial fibrillation
ECG
Electrocardiogram manifestations of thyroid crisis most commonly include
sinus tachycardia and atrial fibrillation
Thyroid sonogram It is frequently helpful, and generally easier in the setting of an
intensive care unit, to obtain a thyroid sonogram with Doppler flow to assess
thyroid gland size, vascularity, and the presence of nodules that may require
further attention. Typically, a thyroid gland secreting excessive
hormones would be enlarged and have enhanced Doppler flow. On the other
hand, in the setting of subacute, postpartum, or silent thyroiditis, or exogenous
causes of hyperthyroidism, the thyroid gland would be expected to
be small, with decreased Doppler flow.
Thyroid sonogram
It is frequently helpful, and generally easier in the setting of an
intensive care unit, to obtain a thyroid sonogram with Doppler flow to assess
thyroid gland size, vascularity, and the presence of nodules that may require
further attention. Typically, a thyroid gland secreting excessive
hormones would be enlarged and have enhanced Doppler flow. On the other
hand, in the setting of subacute, postpartum, or silent thyroiditis, or exogenous
causes of hyperthyroidism, the thyroid gland would be expected to
be small, with decreased Doppler flow.
Nuclear medical imaging Although not always
indicated for diagnosis, given the urgency and clinical context, nuclear medicine
imaging with radioactive iodine uptake and scanning would reveal
a greatly increased uptake of radioiodine as early as 1 or 2 hours after administration
of the isotope, indicating rapid intraglandular turnover of iodine
Nuclear medical imaging
Although not always
indicated for diagnosis, given the urgency and clinical context, nuclear medicine
imaging with radioactive iodine uptake and scanning would reveal
a greatly increased uptake of radioiodine as early as 1 or 2 hours after administration
of the isotope, indicating rapid intraglandular turnover of iodine

Management - Supportive

Fact Explanation
Paracitamol Because fever is very common with severe thyrotoxicosis,
antipyretics should be used; Paracitamol 1g 8 horly is the preferable
choice. Salicylates should be avoided in thyrotoxicosis because salicylates
can decrease thyroid protein binding, causing an increase in free thyroid
hormone levels. External cooling measures, such as alcohol sponging,
ice packs, or a cooling blanket, can also be used
Paracitamol
Because fever is very common with severe thyrotoxicosis,
antipyretics should be used; Paracitamol 1g 8 horly is the preferable
choice. Salicylates should be avoided in thyrotoxicosis because salicylates
can decrease thyroid protein binding, causing an increase in free thyroid
hormone levels. External cooling measures, such as alcohol sponging,
ice packs, or a cooling blanket, can also be used
Hydrocortisone The
role
of
glucocorticoid
therapy
in
thyrotoxic
crisis
has
been
contentious
but
is
almost
universally
accepted.
Glucocrticoids
have
a
dual
role
in
this
situation.
They
inhibit
peripheral
conversion
of
T4
to
T3
and
will
potentially
reduce
active
homone
levels.
Furthermore,
they
will
also
correct
possible
adrenal
insufficiency
which
may
be
present
in
patients
who
have
a
thyroid
crisis
on
the
basis
of
uncontrolled
Graves’
disease.
Hydrocortisone
should
be
given
at
a
dose
of
100mg
every
8
hours
Hydrocortisone
The
role
of
glucocorticoid
therapy
in
thyrotoxic
crisis
has
been
contentious
but
is
almost
universally
accepted.
Glucocrticoids
have
a
dual
role
in
this
situation.
They
inhibit
peripheral
conversion
of
T4
to
T3
and
will
potentially
reduce
active
homone
levels.
Furthermore,
they
will
also
correct
possible
adrenal
insufficiency
which
may
be
present
in
patients
who
have
a
thyroid
crisis
on
the
basis
of
uncontrolled
Graves’
disease.
Hydrocortisone
should
be
given
at
a
dose
of
100mg
every
8
hours
Anticoagulation There
are
conflicting
views
about
the
incidence
of
thromboembolic
disease
in
atrial
fibrillation
(AF)
complicating
thyrotoxicosis.
The
standard
risk
factors
for
embolic
events
in
AF,
including
increasing
age
and
underlying
heart
disease,
apply
to
these
patients
as
well.
The
current
recommendations
are
to
apply
these
criteria
in
decisions
about
anticoagulation.
Thyrotoxic
patients
may
require
a
lower
maintainance
dose
of
warfarin
because
of
the
increased
clearance
of
vitamin
K
dependant
clotting
factors
Anticoagulation
There
are
conflicting
views
about
the
incidence
of
thromboembolic
disease
in
atrial
fibrillation
(AF)
complicating
thyrotoxicosis.
The
standard
risk
factors
for
embolic
events
in
AF,
including
increasing
age
and
underlying
heart
disease,
apply
to
these
patients
as
well.
The
current
recommendations
are
to
apply
these
criteria
in
decisions
about
anticoagulation.
Thyrotoxic
patients
may
require
a
lower
maintainance
dose
of
warfarin
because
of
the
increased
clearance
of
vitamin
K
dependant
clotting
factors
Fluid and supportive therapy Fluid
losses
caused
by
reduced
oral
intake,
increased
sweating,
fever,
vomiting
and
diarrhoea
should
be
vigorously
treated,
with
central
venous
or
arterial
monitoring.
Intravenous
fluids
containing
isotonic
saline
with
5--]10%
dextrose
will
better
restore
depleted
hepatic
glycogen
Fluid and supportive therapy
Fluid
losses
caused
by
reduced
oral
intake,
increased
sweating,
fever,
vomiting
and
diarrhoea
should
be
vigorously
treated,
with
central
venous
or
arterial
monitoring.
Intravenous
fluids
containing
isotonic
saline
with
5--]10%
dextrose
will
better
restore
depleted
hepatic
glycogen

Management - Specific

Fact Explanation
Inhibition of new hormone production Large doses of propylthiouracil (600 mg loading
dose and 200.300 mg every 6 h) should be given PO or
by nasogastric tube or per rectum; the drugs inhibitory
action on T4 to T3 conversion makes it the antithyroid
drug of choice or Methimazole 20–25 mg will
po q 6 hourly will Inhibits new
hormone
synthesis Both of these are used as First-line therapy.All antithyroid drugs inhibit the function of thyroid peroxidase hormone , reducing oxidation and organification of iodide.
These drugs also reduce thyroid antibody levels by
mechanisms that remain unclear, and they appear to
enhance rates of remission.
Inhibition of new hormone production
Large doses of propylthiouracil (600 mg loading
dose and 200.300 mg every 6 h) should be given PO or
by nasogastric tube or per rectum; the drugs inhibitory
action on T4 to T3 conversion makes it the antithyroid
drug of choice or Methimazole 20–25 mg will
po q 6 hourly will Inhibits new
hormone
synthesis Both of these are used as First-line therapy.All antithyroid drugs inhibit the function of thyroid peroxidase hormone , reducing oxidation and organification of iodide.
These drugs also reduce thyroid antibody levels by
mechanisms that remain unclear, and they appear to
enhance rates of remission.
Inhibition of thyroid hormone release One hour after the first dose of propylthiouracil,
stable iodide is given to block thyroid hormone
synthesis via the Wolff-Chaikoff effect (the delay allows
the antithyroid drug to prevent the excess iodine from
being incorporated into new hormone). A saturated
solution of potassium iodide (5 drops SSKI every 6 h), or
ipodate or iopanoic acid (0.5 mg per 12 h),may be given
PO. (Sodium iodide, 0.25 g IV every 6 h, is an alternative
but is not generally available.) Wolff-Chaikoff effect is is a reduction in thyroid hormone levels caused by ingestion of a large amount of iodine It is an autoregulatory phenomenon that inhibits organification in the thyroid gland, the formation of thyroid hormones inside the thyroid follicle, and the release of thyroid hormones into the bloodstream
Inhibition of thyroid hormone release
One hour after the first dose of propylthiouracil,
stable iodide is given to block thyroid hormone
synthesis via the Wolff-Chaikoff effect (the delay allows
the antithyroid drug to prevent the excess iodine from
being incorporated into new hormone). A saturated
solution of potassium iodide (5 drops SSKI every 6 h), or
ipodate or iopanoic acid (0.5 mg per 12 h),may be given
PO. (Sodium iodide, 0.25 g IV every 6 h, is an alternative
but is not generally available.) Wolff-Chaikoff effect is is a reduction in thyroid hormone levels caused by ingestion of a large amount of iodine It is an autoregulatory phenomenon that inhibits organification in the thyroid gland, the formation of thyroid hormones inside the thyroid follicle, and the release of thyroid hormones into the bloodstream
Beta-adrenergic blockade Propranolol 60–80 mg po q 4 h causes Beta-adrenergic
blockade; causing reduction in adrenergic symptoms and also
decreases
T4-to-T3
conversion,or
Atenolol 50–200 mg po qd
used when
cardioselective
agents preferred.Although other β-adrenergic blockers can be used,
high doses of propranolol decrease T4 →T3 conversion,
and the doses can be easily adjusted. Caution is needed
to avoid acute negative inotropic effects, but controlling
the heart rate is important, as some patients develop a
form of high-output heart failure
Beta-adrenergic blockade
Propranolol 60–80 mg po q 4 h causes Beta-adrenergic
blockade; causing reduction in adrenergic symptoms and also
decreases
T4-to-T3
conversion,or
Atenolol 50–200 mg po qd
used when
cardioselective
agents preferred.Although other β-adrenergic blockers can be used,
high doses of propranolol decrease T4 →T3 conversion,
and the doses can be easily adjusted. Caution is needed
to avoid acute negative inotropic effects, but controlling
the heart rate is important, as some patients develop a
form of high-output heart failure
Alternative therapies 1. Lithium
carbonate
300 mg po
q 8 hd will
blocks release of
hormone from
gland; inhibits
new hormone
synthesis
Used when
thionamide or
iodide therapy is
contraindicated;
lithium levels
should be checked
regularly,
2. Potassium
perchlorate
1 g po qds Inhibits iodide
uptake by thyroid
gland
Used in
combination with
thionamide in
treatment of Type
II amiodaroneinduced
thyrotoxicosis
3. Cholestyramine 4 g po qid Decreases
reabsorption of
thyroid hormone
from
enterohepatic
circulation
Used in
combination with
thionamide
therapy.
Alternative therapies
1. Lithium
carbonate
300 mg po
q 8 hd will
blocks release of
hormone from
gland; inhibits
new hormone
synthesis
Used when
thionamide or
iodide therapy is
contraindicated;
lithium levels
should be checked
regularly,
2. Potassium
perchlorate
1 g po qds Inhibits iodide
uptake by thyroid
gland
Used in
combination with
thionamide in
treatment of Type
II amiodaroneinduced
thyrotoxicosis
3. Cholestyramine 4 g po qid Decreases
reabsorption of
thyroid hormone
from
enterohepatic
circulation
Used in
combination with
thionamide
therapy.

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  1. AKAMIZU, T., T. SATOH , O. ISOZAKI , et al. Diagnostic criteria, clinical features, and incidence of thyroid storm based on nationwide surveys. Thyroid.[online]. Mary Ann Liebert. Number 7, 2012. Vol . 22(7). 661-79.[viewed 28 April 2014]. Available from: doi: 10.1089/thy.2011.0334
  2. Bondugulapati, L.N.R., et al. Review-Thyroid Emergencies. SriLanka Journal of Critical Care.[online] Srilanka journals online.info. 2011, vol. 2(1). 1-12 [viwed 28 April 2014]. Available from: www.sljol.info/index.php/SLJCC/article/download/1782/3174
  3. Bondugulapati, L.N.R., et al. Review-Thyroid Emergencies. SriLanka Journal of Critical Care.[online] Srilanka journals online.info. 2011, vol. 2(1). 1-12 [viwed 28 April 2014]. Available from: www.sljol.info/index.php/SLJCC/article/download/1782/3174‎
  4. COLLEDGE N.R., B.R. WALKER, S.H. RALSTON. Davidson's Principles and Practice of Medicine. 21st ed. London. Churchill Livingstone, 2010.
  5. DE ALMEIDA, C.E., E.F. CURI, C.R. De ALMEIDA, D.F. VIEIRA. Thyrotoxic crisis associated with gestational trophoblastic disease. Revista Brasileira de Anestesiologia.[online]. Elsevier. September 2011, vol. 61(5). 604-609 [viewed April 28, 2014]. Available from: www.ncbi.nlm.nih.gov/pubmed/21920210‎
  6. DORLAND W.A.N.Dorland's Illustrated Medical Dictionary.32 nd ed. Philadelphia, Saunders, 2012.
  7. GOODMAN L.S., GILMAN A.G., Goodman and Gilman's the pharmacological basis of therapeutics. 9th ed. New york. McGraw-Hill Companies, 1996.
  8. JAMESON J.L., Harrison's Endocrinology. 2nd ed. McGraw Hill Professional. New york. 2010.
  9. KUMAR, P.J., M.L. CLARK. Kumar and Clark's Clinical Medicine. 8th ed. London: W.B. Saunders Company; 2012
  10. KUMAR, P.J., M.L. CLARK. Kumar and Clark's Clinical Medicine. 8th ed. London: W.B. Saunders Company; 2012.
  11. KUMAR, P.J., M.L. CLARK. Kumar and Clark's Clinical Medicine. 8th ed. London: W.B. Saunders Company; 2012.
  12. Liang, M., H. Wang, L.Tan, M. Feng, Y. Shen, Q. Wang. Successful treatment of thyrotoxic crisis after esophagectomy in an elderly woman with hyperthyroidism. The Annals of Thoracic Surgery[online]. Elsevier.January 2012. Vol. 93(6),141-142. [viewed 28 April 2014]. Available from: doi:10.1016/j.athoracsur.2011.12.042
  13. MIGNECO, A., V. OJETTI, A.TESTA, A. DE LORENZO, N. GENTILONI silveri . Management of thyrotoxic crisis. European Review for Medical and Pharmacological Sciences[online]. Catholic University - Rome (Italy).2005, vol. 9(1),69-74. [viewed 25 April 2014] Available from : www.ncbi.nlm.nih.gov/pubmed/15850146
  14. MIGNECO, A., V. OJETTI, A.TESTA, A. DE LORENZO, N. GENTILONI silveri . Management of thyrotoxic crisis. European Review for Medical and Pharmacological Sciences[online]. Catholic University - Rome (Italy).2005, vol. 9(1),69-74. [viewed 25 April 2014] Available from : www.ncbi.nlm.nih.gov/pubmed/15850146
  15. MIGNECO, A., V. OJETTI, A.TESTA, A. DE LORENZO, N. GENTILONI silveri . Management of thyrotoxic crisis. European Review for Medical and Pharmacological Sciences[online]. Catholic University - Rome (Italy).2005, vol. 9(1),69-74. [viewed 25 April 2014] Available from : www.ncbi.nlm.nih.gov/pubmed/15850146
  16. NAYAK, B., K. BURMAN . Thyrotoxicosis and thyroid storm. Endocrinology Metabolic Clinics of North America[online]. Elsivier. September 2006, vol. 35(4). 663-86,[viewed 25 April 2014]. Available from: doi: 10.1016/j.ecl.2006.09.008
  17. NOH, K.W., C.S. SEON, J.W. CHOI,Y.B. CHO, J.Y. PARK,H.J. KIM. Thyroid storm and reversible thyrotoxic cardiomyopathy after ingestion of seafood stew thought to contain marine neurotoxin. Thyroid[online] Mary Ann Liebert. November 2011. vol. 21(6), 679-82.[viewed 28 April 2014]. Available from: DOI: 10.1089/thy.2010.0276