A 77-year-old man presented with confusion, shortness of breath, and swelling due to untreated hypothyroidism and developed myxedema crisis. Several biases led to doctors not checking the patient's thyroid levels earlier. Myxedema crisis is rare but can result from long-term hypothyroidism if left untreated. The patient's condition rapidly improved after starting thyroid hormone replacement treatment.

1. Myxedema crisis
An uncommon effect of a common condition
Travis Gerrard, MD, PGY3 at Virginia Mason Medical
Center
▪ Hypothyroidism is a common condition
effecting 10% of population
▪ Myxedema crisis is a much less common
but serious sequela of untreated
hypothyroidism
Introduction
Case
Learning points
▪ Features of hypothyroidism were
present in patient prior to
hospitalization (SSS, suborbital edema),
yet surprisingly a TSH was not checked
until hospital day 8. This was the result
of several biases.
▪ Anchoring bias:
▪ PNA as initial diagnosis
▪ Likely a true diagnosis, but also
the precipitant of his myxedema
crisis
▪ As symptoms evolved, anchored
onto common dx in elderly with
premature closure bias
▪ CHF due to ischemia but
deferred cardiac cath given his
acute PNA
▪ CVA with inability to get MRI due
to pacemaker
▪ Availability bias was also present
▪ The above diagnoses are common
in elderly hospitalized patients
▪ Myxedema crisis is an uncommon
diagnosis. Patient presented
without coma or need for
intubation, possibly due to PM
supporting patients cardiac output
▪ Have a low index of suspicion in elderly
to check TSH
▪ Never assume: In this instance that a
TSH had been checked.
Cardiovascular Bradycardia, Hypotension
Respiratory Hypoxia
Gastrointestinal Constipation
Neuropsychiatric Confusion, Lethargy, Poor cognitive
function
Renal and water metabolism Anasarca, Hyponatremia
Metabolic Hypoglycemia
Features of myxedema crisis in patient
References
• Mathew, Vivek et al. “Myxedema Coma: A New Look into an Old Crisis.” Journal of Thyroid
Research 2011 (2011): 493462. PMC. Web. 9 Oct. 2017.
• Popoveniuc, G., Chandra, T., Sud, A., Sharma, M., Blackman, M. R., Burman, K. D., ...
Wartofsky, L. (2014). A diagnostic scoring system for myxedema coma. Endocrine
Practice, 20(8), 808-817. DOI: 10.4158/EP13460.OR
• Kim, J. (2017). Myxedema — NEJM. New England Journal of Medicine. Retrieved 19 October
2017, from http://www.nejm.org/doi/full/10.1056/NEJMicm1403210#t=article
• Bahn, R. (2017). Graves' Ophthalmopathy — NEJM. New England Journal of Medicine.
Retrieved 19 October 2017, from http://www.nejm.org/doi/full/10.1056/NEJMra0905750
• Pathology definition - Myxedema. (2017). Medical Zone. Retrieved 19 October 2017, from
http://www.medicalzone.net/pathology-definition---myxedema.html
▪ 77 y/o male who 5 years ago developed sick sinus
syndrome (SSS) and underwent pacemaker (PM)
implantation
▪ 3 months ago noted to have suborbital edema
▪ Presented in the night with confusion, SOB,
purulent cough, anasarca
▪ Started on abx given finding of infiltrate on chest
CT
▪ Hospital day (HD) 2 patient developed dysarthria,
hypotension, hypoxemia & hypoglycemia.
▪ Work up for stroke, Addison's, ACS only
remarkable ECHO showing left ventricular ejection
fraction of <40%, global hypokinesis. Unable to get
head MRI due to PM
▪ HD 5, senior residents switch, patient has first
bowel movement of hospital stay
▪ HD 7, interns off. Pt with persistent hypotension &
hypoglycemia. Surprise when discovered patient
never had TSH checked
▪ HD 8, on AM labs patient found to be profoundly
hypothyroid, IV replacement with levothyroxine is
initiated
▪ HD 9, patient with rapid improvement of confusion,
hypoxia, hypotension & hypoglycemia
Examples of suborbital edema