DIAGNOSTICS TEST 2 NSG 535 | COMPREHENSIVE NURSING
DIAGNOSTICS STUDY GUIDE, PRACTICE QUESTIONS & ANSWERS
2026/2027
What is the primary function of the thyroid gland? - ANS ✔✔To produce thyroid hormones (T3 and T4)
that regulate metabolism and various bodily functions.
What are the two main hormones produced by the thyroid? - ANS ✔✔Thyroxine (T4) and
Triiodothyronine (T3).
How is thyroid hormone production regulated? - ANS ✔✔Through a negative feedback loop involving
the hypothalamus and pituitary gland.
What hormone does the hypothalamus produce to stimulate the thyroid? - ANS ✔✔Thyroid releasing
hormone (TRH).
What is the role of thyroid stimulating hormone (TSH)? - ANS ✔✔TSH stimulates the thyroid gland to
produce T3 and T4.
What is a primary thyroid disorder? - ANS ✔✔A condition where the problem originates from the
thyroid gland itself.
What characterizes a secondary thyroid disorder? - ANS ✔✔The thyroid gland is functioning normally,
but there is a problem with the pituitary gland affecting TSH levels.
What is a tertiary thyroid disorder? - ANS ✔✔A condition where both the thyroid and pituitary are
normal, but the hypothalamus is not functioning properly.
What is the significance of thyroxine (T4) in thyroid function testing? - ANS ✔✔T4 is a better indicator of
thyroid status because only a small percentage circulates unbound to proteins.
What is the normal range for TSH levels? - ANS ✔✔0.4-6.0 (lab dependent).
What does an increased TSH level indicate? - ANS ✔✔It may indicate hypothyroidism, as the pituitary
produces more TSH when T4/T3 levels are low.
What is the most active form of thyroid hormone? - ANS ✔✔Triiodothyronine (T3).
What is the role of calcitonin? - ANS ✔✔Calcitonin is used to detect medullary thyroid cancer.
Which protein binds T3 and T4 in the bloodstream? - ANS ✔✔Thyroid binding globulin (TBG).
What is the primary use of antithyroid antibodies (TgAb)? - ANS ✔✔To bind to TSH receptors and can
stimulate or inhibit their function, often found in autoimmune thyroid disease.
, What is the purpose of a thyroid scan (scintigraphy)? - ANS ✔✔To measure the accumulated
radioactivity in the thyroid to differentiate possible causes of hyperthyroidism.
What does fine needle aspiration (FNA) cytology detect? - ANS ✔✔It detects thyroid cancer and other
disorders with a sensitivity of 70-90%.
What is the significance of free T4 in thyroid testing? - ANS ✔✔Free T4 is the most important measure
for determining how the thyroid is functioning as it enters target tissues.
What is the relationship between T4 and TSH levels? - ANS ✔✔TSH production is inversely related to T4
and T3 concentrations due to the negative feedback mechanism.
What is the role of iodine in thyroid hormone synthesis? - ANS ✔✔Iodine is necessary for the production
of T3 and T4, as T4 contains four iodine atoms.
What is the primary indicator for hyperthyroidism testing? - ANS ✔✔Total T3 and Free T3 are often
measured to check for hyperthyroidism.
What is the significance of equilibrium dialysis in thyroid testing? - ANS ✔✔It provides a more direct
measure of free T4, which is biologically more active than total T4.
What are common causes of autoimmune thyroid disease? - ANS ✔✔Hashimoto thyroiditis
(hypothyroidism) and Grave's disease (hyperthyroidism).
What is the function of the liver in thyroid hormone metabolism? - ANS ✔✔The liver metabolizes and
degrades T4 and converts it to T3 by removing an iodine atom.
What are the common symptoms of hypothyroidism? - ANS ✔✔Memory problems, oversleeping, muscle
weakness, sensitivity to cold, slow heart rate, weight gain, tiredness, intolerance to cold, elevated
cholesterol, dry skin and hair.
What is the most common type of hypothyroidism? - ANS ✔✔Hashimoto's thyroiditis, accounting for
90% of cases.
What is a hot nodule in thyroid diagnosis? - ANS ✔✔An autonomous nodule that takes up more
radioactive iodine than surrounding tissue, indicating it is actively producing thyroid hormones.
What is a cold nodule in thyroid diagnosis? - ANS ✔✔A nodule that shows reduced uptake of iodine,
indicating it may not be producing thyroid hormones; it can be benign or malignant.
What diagnostic tests are ordered for suspected hypothyroidism? - ANS ✔✔TSH (increased), Free T4
(decreased), Thyroid peroxidase antibody, Thyroglobulin antibody.
What characterizes primary hypothyroidism? - ANS ✔✔Increased TSH and decreased Free T4 levels.
What characterizes secondary hypothyroidism? - ANS ✔✔Mildly increased TSH with normal Free T4
levels, often due to pituitary issues.
DIAGNOSTICS STUDY GUIDE, PRACTICE QUESTIONS & ANSWERS
2026/2027
What is the primary function of the thyroid gland? - ANS ✔✔To produce thyroid hormones (T3 and T4)
that regulate metabolism and various bodily functions.
What are the two main hormones produced by the thyroid? - ANS ✔✔Thyroxine (T4) and
Triiodothyronine (T3).
How is thyroid hormone production regulated? - ANS ✔✔Through a negative feedback loop involving
the hypothalamus and pituitary gland.
What hormone does the hypothalamus produce to stimulate the thyroid? - ANS ✔✔Thyroid releasing
hormone (TRH).
What is the role of thyroid stimulating hormone (TSH)? - ANS ✔✔TSH stimulates the thyroid gland to
produce T3 and T4.
What is a primary thyroid disorder? - ANS ✔✔A condition where the problem originates from the
thyroid gland itself.
What characterizes a secondary thyroid disorder? - ANS ✔✔The thyroid gland is functioning normally,
but there is a problem with the pituitary gland affecting TSH levels.
What is a tertiary thyroid disorder? - ANS ✔✔A condition where both the thyroid and pituitary are
normal, but the hypothalamus is not functioning properly.
What is the significance of thyroxine (T4) in thyroid function testing? - ANS ✔✔T4 is a better indicator of
thyroid status because only a small percentage circulates unbound to proteins.
What is the normal range for TSH levels? - ANS ✔✔0.4-6.0 (lab dependent).
What does an increased TSH level indicate? - ANS ✔✔It may indicate hypothyroidism, as the pituitary
produces more TSH when T4/T3 levels are low.
What is the most active form of thyroid hormone? - ANS ✔✔Triiodothyronine (T3).
What is the role of calcitonin? - ANS ✔✔Calcitonin is used to detect medullary thyroid cancer.
Which protein binds T3 and T4 in the bloodstream? - ANS ✔✔Thyroid binding globulin (TBG).
What is the primary use of antithyroid antibodies (TgAb)? - ANS ✔✔To bind to TSH receptors and can
stimulate or inhibit their function, often found in autoimmune thyroid disease.
, What is the purpose of a thyroid scan (scintigraphy)? - ANS ✔✔To measure the accumulated
radioactivity in the thyroid to differentiate possible causes of hyperthyroidism.
What does fine needle aspiration (FNA) cytology detect? - ANS ✔✔It detects thyroid cancer and other
disorders with a sensitivity of 70-90%.
What is the significance of free T4 in thyroid testing? - ANS ✔✔Free T4 is the most important measure
for determining how the thyroid is functioning as it enters target tissues.
What is the relationship between T4 and TSH levels? - ANS ✔✔TSH production is inversely related to T4
and T3 concentrations due to the negative feedback mechanism.
What is the role of iodine in thyroid hormone synthesis? - ANS ✔✔Iodine is necessary for the production
of T3 and T4, as T4 contains four iodine atoms.
What is the primary indicator for hyperthyroidism testing? - ANS ✔✔Total T3 and Free T3 are often
measured to check for hyperthyroidism.
What is the significance of equilibrium dialysis in thyroid testing? - ANS ✔✔It provides a more direct
measure of free T4, which is biologically more active than total T4.
What are common causes of autoimmune thyroid disease? - ANS ✔✔Hashimoto thyroiditis
(hypothyroidism) and Grave's disease (hyperthyroidism).
What is the function of the liver in thyroid hormone metabolism? - ANS ✔✔The liver metabolizes and
degrades T4 and converts it to T3 by removing an iodine atom.
What are the common symptoms of hypothyroidism? - ANS ✔✔Memory problems, oversleeping, muscle
weakness, sensitivity to cold, slow heart rate, weight gain, tiredness, intolerance to cold, elevated
cholesterol, dry skin and hair.
What is the most common type of hypothyroidism? - ANS ✔✔Hashimoto's thyroiditis, accounting for
90% of cases.
What is a hot nodule in thyroid diagnosis? - ANS ✔✔An autonomous nodule that takes up more
radioactive iodine than surrounding tissue, indicating it is actively producing thyroid hormones.
What is a cold nodule in thyroid diagnosis? - ANS ✔✔A nodule that shows reduced uptake of iodine,
indicating it may not be producing thyroid hormones; it can be benign or malignant.
What diagnostic tests are ordered for suspected hypothyroidism? - ANS ✔✔TSH (increased), Free T4
(decreased), Thyroid peroxidase antibody, Thyroglobulin antibody.
What characterizes primary hypothyroidism? - ANS ✔✔Increased TSH and decreased Free T4 levels.
What characterizes secondary hypothyroidism? - ANS ✔✔Mildly increased TSH with normal Free T4
levels, often due to pituitary issues.
