Download Identifying Central Hypothyroidism in Persons with

Identifying Central Hypothyroidism in Persons with Traumatic Brain Injury
Elizabeth Reusche BSN, RN & Mary Anne Saveoz BSN, RN, CRRN
Introduction
Individuals who have sustained
Traumatic Brain Injury (TBI) frequently
develop pituitary and/or hypothalamic
dysfunction. This is a contributing
factor to central hypothyroidism whose
onset is not related to injury severity
and can, in fact, develop several to
many years post injury. This poster will
define
central
hypothyroidism,
indications for ongoing evaluation of
pituitary hormone secretion, current
diagnostic tools and treatment with
adequate hormonal therapy. The
rehabilitation nurse’s involvement is
critical in advocating for these
individuals for proper diagnosis and
treatment.
Pituitary Gland- Referred to as the
“master gland”. Anterior pituitary has
many functions. A critical hormone it
produces is TSH which stimulates the
thyroid gland to produce Thyroxine.
Hypothalamus – A midbrain structure
that produces hormones which direct
the pituitary gland to stimulate the
thyroid gland.
Thyroid Gland- Secretes Thyroxine
(T4) which is needed for growth and
development. Located in the lower
throat region.
Primary Hypothyroidism is a
dysfunction occurring at the level of
the thyroid gland.
Causes
• Autoimmune disease (Hashimoto
disease)
• Thyroid surgery
• Radiation therapy
• Medication
Comprehensive medical history,
physical exam, and extensive lab
work. Low serum TSH concentration
in the presence of subnormal T4 and
T3 concentration is characteristic of
central hypothyroidism.
Signs and Symptoms of
Hypothyroidism
•
•
•
•
•
•
•
•
•
•
•
•
Weakness, fatigue •
Dry skin
Cool extremities •
Puffy face, hands •
Difficulty hearing
Alopecia
•
Paresthesia
•
Bradycardia
Menorrhagia
•
Poor concentration •
Peripheral edema
Poor memory
Delayed tendon
reflex relaxation
Constipation
Carpal tunnel
syndrome
Weight gain
Serous cavity
effusions
Dyspnea
Hoarse voice
Male: Date of Injury- 2008 (age 30)
 Diagnosed with Hypothyroidism in
February 2013 (age 35, 5 yrs post injury)
 Managed by PCP
 No T3/T4 levels were monitored
Date
2/2013
6/2013
12/2014
5/2015
TSH
5.02
0.85
4.83
4.93
Levothyroxine
50 mcg
50 mcg
50 mcg
75 mcg
Female: Date of Injury- 1989 (age 17)
Secondary or Tertiary
Hypothyroidism (central
hypothyroidism) is a defect at the
pituitary, hypothalamus, or
hypothalamic portal circulation level
Causes
• Certain drugs such as opiates,
glucocorticoids, dobutamine, and
dopamine
• Space occupying lesions of the
brain or pituitary
• Radiation
• Traumatic brain injury
• Growth hormone therapy
• Genetic mutations
• Idiopathic causes
Case Studies
Diagnosis
Definitions & Causes
 Diagnosed with Hypothyroidism in March
2009 (age 37, 20 yrs post injury)
 Managed by PCP
 No T3/T4 levels were monitored
Treatment
A majority of people are treated with
Levothyroxine. The principle of this
treatment includes replacement of
thyroid hormone.
Labs are monitored for serum TSH T3
and T4 levels with the goal of
maintaining these levels in the higher
range of normal.
Client Review
•
•
•
•
•
•
•
•
Total of 29 clients
Females n=11, Males n=18
Age range: 40 – 60 years
Hypothyroidism diagnosis: 7 clients
(5 females, 2 males) This is 24% of
reviewed population
Levothyroxine doses:
Female 25mcg – 112mcg
Male 50mcg-75mcg
One female diagnosed with Grave’s
Disease in 2000 (two years prior to
injury) and was treated with I-131.
Date
3/2009
3/2010
2/2011
7/2011
12/2012
2/2013
4/2013
6/2013
3/2015
TSH
7.32
5.36
3.95
2.28
3.95
3.28
2.45
1.67
3.40
T4
-----0.9
--1.2
Levothyroxine
25 mcg
50 mcg
50 mcg
50 mcg
50 mcg
75 mcg
100 mcg
100 mcg
112 mcg
Conclusions
Individuals who have sustained TBI
frequently
develop
pituitaryhypothalamic dysfunction which is a
contributing
factor
to
central
hypothyroidism. The onset of central
hypothyroidism is not related to the
severity of the injury. Central
hypothyroidism, most importantly, can
arrive several to many years after
injury. Ongoing evaluation of pituitary
hormone
secretion
should
be
included in long term follow up of all
TBI patients so proper diagnosis can
be made and adequate hormonal
therapy administered.