Case 1Name:Gender: Female Age: 30 YeasMarital State: Married + 2 Residence: Alexandria – EgyptOccupation: HousewifeSpecial Habits: Nil (no smoking)

Complaints: Loss of weight Irritable Uncomfortable with summer weather

Examination:• Pulse: 130 • Blood pressure: 155/95• Palm sweaty Fine tremors of the fingers when her arms are stretched No eye signs Thyroid gland enlarged – No nodules

HistoryOn contraceptive pills containing estrogen

Investigations: Thyroid function tests

Further investigations:

Diagnosis:

Treatment:

Clinical Biochemistry LabUnit of Endocrinal Investigations

Thyroid Function TestsName of Patient : Case 1 DOB: 31/10/1983Gender: Female

Date of investigation:: 23/7/2012Sample type: BloodSample Number: 91024

Analysis Result Reference Range

TSH 0.1 mIU/L 0.3 – 0.5Free T4 20 pmol/L 10-27Total T4 160 nmol/L 70-150Free T3 20 pmol/L 3- 9Total T3 6 nmol/L 1.2-2.8

Case 2Gender: Male Age: 38 YeasMarital State: Married + 3 Occupation: Engineer

• He came to the outpatient clinic for follow up of his treatment • He was already diagnosed as Graves disease • Started treatment 3 months ago

Investigations: Thyroid function tests

Comments: ??

Recommendations: ??

Clinical Biochemistry LabUnit of Endocrinal Investigations

Thyroid Function TestsName of Patient : Case 2 DOB: 12/11/1975Gender: Male

Date of investigation:: 2/4/2013Sample type: BloodSample Number: 101123

Analysis Result Reference Range

TSH less than 0.1 mIU/L 0.3 – 0.5Free T4 5 pmol/L 10 - 27Total T4 100 nmol/L 70-150Free T3 2.9 pmol/L 3- 9Total T3 0.9 nmol/L 1.2-2.8

Case 3Name:Gender: Female Age: 26 YearsMarital State: Single Occupation: Student Residence: Al-Wahat Al-Kharja- EGYPTSpecial Habits: Nil

Complaints:Tired and feeling low all the timeGaining weightDiscomfort in her neck

Examination:Pulse: 55 BP: 108/65Palm dryThyroid examination: Goiter

Investigations: Thyroid function tests

Further investigations: ??

Diagnosis: ??

Treatment:?? Follow up:

Clinical Biochemistry LabUnit of Endocrinal Investigations

Thyroid Function TestsName of Patient : Case 3 DOB: 12/11/1984Gender: Female

Date of investigation:: 24/9/2010Sample type: BloodSample Number: 80656

Analysis Result Reference Range

TSH 48 mIU/L 0.3 – 0.5Free T4 8 pmol/L 10 - 27Total T4 56 nmol/L 70-150Free T3 6 pmol/L 3- 9Total T3 1.9 nmol/L 1.2-2.8

In individuals with iodide deficiency,

what is the cause of the thyroid enlargement ??(Goiter Formation)

Answer:

Elevation of TSH is the mechanism for goiter formation

Decreased thyroid hormone levels reduce feedback inhibition of TSH secretion by the pituitary.

TSH secretion is increased.

TSHacts as a growth factor for the thyroid gland

increasing its mass

Increase its capacity to synthesize thyroid hormones

Case 4:A 25-year old female asked her family doctor for a tretment her constant fatigue, lethargy & depression. She was small in stature & had previously been diagnosed with attention-deficit disorder.(recorded in her medical file).

On physical examinationShe was found to have an enlarged thyroid gland (goiter).

HOWEVER!!Blood tests revealed elevated levels of T3, T4 and TSH, yet she did not exhibit typical symptoms of hyperthyroidism.

How can you explain this case???

WHAT DO YOU THINK???

Thyroid hormone overproduction because of a thyroid gland tumor ?

Or

Hypersecretion of TSH because of a pituitary tumor?

Or

Genetic alteration in the thyroid receptor reducing its ability to bind thyroid hormone?

Or

Mutation in the TSH receptor in the thyroid gland reducing its ability to bind TSH ?

Or

Iodide deficiency in the diet ?

Answer is C:

The patient exhibits symptoms of hypothyroidism including goiter …etc,yet thyroid hormone levels are elevated.

This pattern can only beexplained by resistance of target cells to thyroid hormone,

for example,a mutation of the receptor decreasing its binding affinity for hormone

N.B. Iodide deficiency would lead to goiter but not increased hormone levels