Hypothyroidism
Concept and Etiology: How does the disease affect the endocrine and neural body systems in
particular? How does it deviate from the definition of health discussed in Module One?
With hypothyroidism, the thyroid gland does not product adequate thyroid hormones. This is a
common disorder, usually managed with medications such as levothyroxine.
Classification: How is the disease classified?
Hypothyroidism has four classifications. Primary due to thyroid hormone deficiency, secondary due
to TSH deficiency, tertiary due to thyrotropin-releasing deficiency, and peripheral due to extra-
thyroidal conditions (Chaker et al., 2017).
Clinical Manifestations (Symptoms and Signs): What are the symptoms and signs of the disease or
disorder? Be sure you understand the difference between symptoms (subjective) and signs
(objective).
Hypothyroidism is manifested with fatigue, sluggishness, increased sensitivity to cold, constipation,
pale and dry skin, edema in the face, hands, and feet, hoarseness, hypercholesterolemia,
unexplained weight gain, myalgia, arthralgia, muscle weakness, heavier than normal menstrual
periods, infertility, brittle fingernails, hair loss or thinning, bradycardia, hypotension, depression,
and goiter (Story, 2018).
Diagnostic Tests: What are some additional diagnostic tests that can be done to illuminate the
diagnosis? For example, when you injure your ankle, they take an X-ray to determine if it is broken
or sprained.
Diagnostic testing for hypothyroidism includes patient history, physical examination, bloodwork
that includes serum thyroid hormone levels, serum TSH, liver function tests, complete blood count
(CBC), cholesterol panel, and electrocardiogram (EKG).
Encephalitis is inflammation of the brain parenchyma and occasionally spinal cord from infection,
autoimmune conditions, or (in rare cases) allergic reaction. Encephalitis is most commonly the
result of a viral infection, with the most common sporadic encephalitis cases in the US caused by
HSV (Greenlee, 2020). Direct viral invasion of the brain usually damages neurons, and severe
infections can cause bleeding from the cerebral vasculature and haemorrhagic necrosis (Greenlee,
2020). Given that the definition of health in almost every case necessitates the relative absence of
disease or infirmity, acute infection or autoimmune response is directly contrary to the definition of
health.
Infectious encephalitis is defined as either primary or secondary. Primary encephalitis results from
direct infection of the brain or spinal cord, where secondary infection begins elsewhere in the body
and then travels to the brain or spinal cord (Story, 2017). Autoimmune encephalitis is subclassified
either based on anatomic location or the causative antibody (Farkas, 2021).
Encephalitis, especially from an infectious source, often begins with generalized flu-like symptoms
and malaise. Diplopia, photophobia, and headache are often the first symptoms to appear, followed
by hallmark symptoms of encephalopathy: altered mental status optionally with ataxia, tremor, or
myoclonus, and/or focal neurological deficits. Bulging fontanelle can sometimes be found in infants.
Diagnostic tests include CSF analysis including opening pressures, cell count, and culture; serum labs
including blood culture, HIV serology, and treponemal testing; imaging of the brain (MRI preferred
to CT) and chest (XR or CT); and EEG (Venkatesan & Geocadin, 2014). A requirement for ruling-in
encephalitis is altered mental status for 24 hours or greater. This must be accompanied by 2 or
more of the following that are not attributable to another cause or underlying condition:
documented fever within 72 hours, seizure, new focal neurological findings, abnormal imaging of
brain parenchyma consistent with encephalitis, abnormal EEG, or presence of leukocytes >= 5/mL in
CSF (Venkatesan & Geocadin, 2014).
Myasthenia gravis
Concept and Etiology: How does the disease affect the endocrine and neural body systems in
particular? How does it deviate from the definition of health discussed in Module One?
Myasthenia gravis is an autoimmune disorder that attacks the communication between the nerve
and the muscles, causing muscles to become weak. The antibodies can block the protein muscle-
specific receptor tyrosine kinase or lipoprotein-related protein 4. However, there are some people
that have the disease without these antibodies, which is known as seronegative (Mayo Clinic, 2021).
It typically occurs in young woman aged 20-30, or older males age 50 or older. (John Hopkins
Medicine, n.d.)
Classification: How is the disease classified?
Myasthenia gravis is a prototypic autoimmune disease caused by antibodies to the acetylcholine
receptor (AChR) leading to weakness of the ocular, bulbar, respiratory, axial, and limb muscles
(Hehir & Silvestri, 2018).
Clinical Manifestations (Symptoms and Signs): What are the symptoms and signs of the disease or
disorder? Be sure you understand the difference between symptoms (subjective) and signs
(objective).
Signs
Drooping eye lids
Facial muscle involvement, i.e., a smile looking more like a snarl
Short of breath
Paralysis
Symptoms
Weakness
Trouble swallowing
Fatigue
Hoarseness/ voice changes
Diagnostic Tests: What are some additional diagnostic tests that can be done to illuminate the
diagnosis? For example, when you injure your ankle, they take an X-ray to determine if it is broken
or sprained.
Some diagnostic tests that can be performed to evaluate for myasthenia’s gravis are nerve
conduction and single-fibre EMG. Blood test to test for the presence of acetylcholine receptor
antibodies can be tested for, a Tension test can evaluate baseline muscle strength. They may also
perform a CT or MRI scan of the chest to check for a thyroid tumour (Signs-and-Symptoms.org,
2017).
References
Hehir, M. K., & Silvestri, N. J. (2018). Generalized Myasthenia Gravis: Classification, Clinical
Presentation, Natural History, and Epidemiology. Neurol Clinic. Doi: 10.1016/j.ncl.2018.01.002
John Hopkins Medicine. (n.d.). Myasthenia Gravis. Retrieved November 17, 2021, from John
Hopkins Medicine: https://www.hopkinsmedicine.org/health/conditions-and-diseases/myasthenia-
gravis
Mayo Clinic. (2021, June 22). Myasthenia gravis. Retrieved from Mayo Clinic:
https://www.mayoclinic.org/diseases-conditions/myasthenia-gravis/symptoms-causes/syc-
20352036
Signs-and-Symptoms.org. (2017). Myasthenia Gravis Signs and Symptoms. Retrieved from Signs-and-
Symptoms.org: https://www.signs-and-symptoms.org/myasthenia-
gravis/#:~:text=The%20Most%20Common%20Signs%20and%20Symptoms%20of%20Myasthenia,Ch
oking%209%20Paralysis%2010%20Hoarseness%20or%20Changing%20Voice
Story, L. (2017). Pathophysiology: A Practical Approach (3rd Edition). Jones & Bartlett Learning.
https://mbsdirect.vitalsource.com/books/9781284142983
Farkas, J. (2021, May 21). Autoimmune Encephalitis. EMCrit Project. https://emcrit.org/ibcc/ae/
Greenlee, J. E. (2020, July). Encephalitis - Neurologic Disorders. Merck Manuals Professional Edition.
https://www.merckmanuals.com/professional/neurologic-disorders/brain-infections/encephalitis
Venkatesan, A., & Geocadin, R. G. (2014). Diagnosis and management of acute encephalitis: A
practical approach. Neurology: Clinical Practice, 4(3), 206–215.
https://doi.org/10.1212/cpj.0000000000000036
Chaker, L., Bianco, A. C., Jonklaas, J., & Peeters, R. P. (2017). Hypothyroidism. The Lancet,
390(10101), 1550–1562. https://doi.org/10.1016/s0140-6736(17)30703-1
Story, L. (2018). Pathophysiology: a practical approach (3rd ed.). Jones & Bartlett Learning.
