Tiroides Flashcards
¿Qué significa T4?
a) Tetrayodotironina
b) Triyodotironina
c) tiroxina
a) Tetrayodotironina y c) tiroxina son correctas
¿Qué significa T3?
a) Tetrayodotironina
b) Triyodotironina
c) tiroxina
b) Triyodotironina
Hormona tiroidea en mayor cantidad pero menor potencia:
a) T3
b) T4
c) T5
b) T4
Hormona tiroidea en menor cantidad pero mayor potencia:
a) T3
b) T4
c) T5
a) T3
¿Cuál enunciado es correcto?
a) T3, tiroxina, se convierte en iodinasa en tejidos.
b) T4, tiroxina, se convierte en iodinasa en tejidos.
c) T4 se convierte en T3 en los tejido con iodinasa
d) T3 se convierte en T4 en los tejido con iodinasa
c) T4 se convierte en T3 en los tejido con iodinasa
Enfermedad de Graves, Adenoma tóxico, bocio multinodular e ….. farmacológico son tipos de enfermedades de :
a) hipotiroidismo
b) hipertiroidismo
b) hipertiroidismo
Bocio por deficiencia de yodo, tiroiditis crónica y destrucción de la glándula son tipos de enfermedades de :
a) hipotiroidismo
b) hipertiroidismo
a) hipotiroidismo
Tratamientos para enfermedades tiroideas:
Tioamidas,
yodo radioactivo,
preparados de hormonas tiroideas
¿Cuál es el mecanismo de acción de la Tioamida: Metimazol?
a) inhibe tioperoxidasa > bloquea organificación del yodo
b) inhibe conversión de T4 a T3 en tejidos
c) ambas son correctas
a) inhibe tioperoxidasa > bloquea organificación del yodo
¿Cuál es el mecanismo de acción de la Tioamida: Propiltiouraiclo (PTU)?
a) inhibe tioperoxidasa > bloquea organificación del yodo
b) inhibe conversión de T4 a T3 en tejidos
c) ambas son correctas
c) ambas son correctas
Fármacos para hipertiroidismo usados p/prepar px para tiroidectomía o yodo reactivo; y en crisis tirotóxicas:
Metimazo y PTU
Con tiaminas se logra remisión completa (30-40%) en más de año y medio en la:
a) Sx Sjörgen
b) enfermedad de Graves
c) tiroiditis
b) enfermedad de Graves
Fármaco que se reserva para pacientes alérgicos o intolerantes al metimazol. Para px embarazadas 1er trimestre o que busquen embarazarse. Y en tormenta tiroidea:
a) metimazol
b) propiltiouracilo - PTU
b) propiltiouracilo - PTU
Son efectos adversos de las tioamidas:
a) lesión hepática (mortal) y leucopenia transitoria benigna
b) lupus eritematoso y exantema maculopapular
c) neutropenia y agranulocitosis (grave)
Todas son correctas
¿Cómo es la dosificación de las tioamidas?
Se comienza con dosis elevada y se va reduciendo posteriormente.
¿Cuáles son los yodos radioactivos?
I-131 y I-123
____ entra a la glándula tiroides, emite rayos beta destruyendo el tejido.
a) I-123
b) I-131
c) I-121
d) I-132
b) I-131
____ se usa con fines diagnóstico.
a) I-123
b) I-131
c) I-121
d) I-132
a) I-123
¿Cuáles son las indicaciones para yodo radioactivo?
Hipertiroidismo y Posteriori a tiroidectomía en cáncer tiroideo.
El yodo radioactivo es CONTRAINDICADO en embarazo o previo a él, ¿por qué?
Porque destruye igualmente el tejido tiroideo fetal.
Al usar yodo radioactivo se deben evitar el consumo de _____ pues reduce eficacia terapéutica.
Tioamidas.
Menciona los 3 preparados de hormonas tiroideas:
Levoriroxina, Liotironina y Combinación de ambas.
Fármaco de selección para tx sustitutiva, disminución de TSH y previo a tiroidectomía:
Levotiroxina (T4)
Fármaco poco usado, de vía intravenosa al tx coma mixedematoso:
Liotironina (T3)
Alimentos y otros fármacos disminuyen abolición de _______, por ello consumir con 2 hrs de diferencia.
a) liotironina (T3)
b) combinación de ambos
c) levotiroxina (T4)
c) levotiroxina (T4)
Levothyroxine use is contraindicated in px with which one of these conditions?
a) hypertension
b) uncorrected adrenal insufficiency
c) end-stage renal disease
d) cirrhosis
b) uncorrected adrenal insufficiency
In general, adverse effects associated with levothyroxine are due to incorrect or excessive dosing. Which one of these adverse effects is more commonly associated with levothyroxine use?
a) Decreased appetite
b) Weight gain
c) Polyuria
d) Angina pectoris
d) Angina pectoris
Which statement is most accurate regarding levothyroxine toxicity?
a) onset of sign san symptoms of levothyroxine toxicity has been delayed as long as 10 days
b) a one-time ingestion of as much as 2 mg of levothyroxine typically causes severe complications in children and adults
c) common signs and symptoms associated with levothyroxine toxicity include constipations, extreme fatigue, and bradycardia
d) serious health concerns related to levothyroxine toxicity are more common in children than in adults for the same overdose ingested
a) onset of sign san symptoms of levothyroxine toxicity has been delayed as long as 10 days
Which medica>on is most well recognized as a cause of hypothyroidism?
a) Lithium
b) Amoxicilin
c) Metoprolol
d) Metformin
a) Lithium
Which is most commonly recognized as a sign or symptom of hypothyroidism?
a) Emotional lability
b) Weight loss
c) Tachycardia
d) Hyperhidrosis
a) Emotional lability
What’s the first tx for thyroid eye disease?
a) teprotumumab
b) mertormin
c) levothyroxine
a) teprotumumab
“Un inhibidor de IGF-IR del receptor del factor de crecimiento similar a la insulina 1 (dentro de la órbita del ojo)” es el mecanismo de acción de:
Teprotumumab
Untreated hyperthyroidism + stress like infections or illness can lead to a life threatening disease called:
thyroid storm
____________ is the primary mechanism of action of methimazole.
Inhibition of thyroid peroxidase
Methimazole is recommended for use during the (1st/2nd/3rd/no) _____________ trimester of pregnancy in patients with hyperthyroid.
2nd and 3rd
Propylthiouracil (is/is not) ______ safe for use during the first trimester of pregnancy in patients with hyperthyroidism.
is
_________ and methimazole are two hyperthyroidism medications that can cause agranulocytosis and aplastic anemia.
Propylthiouracil (PTU)
_______ is a thioamide that inhibits the enzyme thyroid peroxidase only, and does not have peripheral activity.
Methimazole
______ and propylthiouracil are two medications used in the treatment of hyperthyroidism.
Methimazole
______ is a possible teratogenic complication of Methimazole.
Aplasia cutis
______ is the black box warning of propylthiouracil.
Hepatotoxicity
______ is a rare hematological complication of propylthiouracil and methimazole use.
Agranulocytosis
______ and methimazole are thioamides used in hyperthyroidism and are associated with agranulocytosis.
Propylthiouracil (PTU)
______ is a thioamide that inhibits thyroid peroxidase and 5’-deiodinase at peripheral tissues.
Propylthiouracil (PTU)
Propylthiouracil (inhibits/stimulates) ______ conversion of T4 to T3.
inhibits
______ is a hyperthyroid medication that inhibits both thyroid peroxidase and 5′-deiodinase.
Propylthiouracil (PTU)
______ is a short acting thioamide.
Propylthiouracil (PTU)
A 6-hour-old male delivered at 37 weeks’ gestation is found to have a lesion on the right side of his scalp, with out skin. On further inspection, the lesion is non-inflammatory and involves both the epidermis and upper dermis. The infant was delivered by normal vaginal delivery and has microcephaly and polydactyly of the right hand. The mother had little prenatal care and has no past medical history, aside from hyperthyroidism which was treated with methimazole throughout the pregnancy. Which of the following is the most likely diagnosis?
a) Aplasia cutis congenita
b) Birth trauma
c) Epidermolysis bullosa
d) Focal dermal hypoplasia
e) Neonatal herpes infection
a) Aplasia cutis congenita
An 18-year-old woman comes to the clinic because of tachycardia, nervousness, decreased exercise tolerance, and weight loss over the past 6 months. She was previously healthy and takes no medications. Her sister has Graves disease. Her pulse is 124/min, respirations are 18/min, and blood pressure is 128/78 mm Hg. Her BMI is 19 kg/m2. There is no proptosis. Examination of the neck shows a smooth and enlarged thyroid gland. Cardiac examination shows regular tachycardia. Her lungs are clear to auscultation. Laboratory studies are obtained and show:
Thyroid-stimulating hormone: <0.01 µU/mL
Thyroxine (T4 ): 15.5 μg/dL
Triiodothyronine (T3 ): 240 ng/L
Which of the following is the most appropriate treatment for this patient?
a)Propranolol
b) Propranolol and methimazole
c) Methimazole
d) Propylthiouracil
e) Radioactive iodine and methimazole
b) Propranolol and methimazole
A 29-year-old woman comes to the clinic because of heat intolerance, excessive sweating, and thinning hair. She has a family history of auto-immune disease, including rheumatoid arthritis. She is 8 weeks’ pregnant and has had no other issues during the pregnancy. Medical history includes hyperthyroidism. Laboratory serum studies are positive for thyroid stimulating immunoglobulin. Which of the following drugs is most appropriate for the treatment of the patient’s condition?
a) Methimazole
b) Oxytocin
c) Propylthiouracil
d) Radioactive iodine
e) Synthetic T4
c) Propylthiouracil
______ is a thyroid hormone produced from its prohormone, thyroxine.
Triiodothyronine (T3)
In cells, thyroxine is a thyroid hormone that is converted by deiodinases to its more potent form, _________.
Triiodothyronine (T3)
Patients on thyroid replacement therapy such as levothyroxine require ______ weeks to achieve steady state.
6 to 8 weeks
Intravenous ______ and levothyroxine are the treatments for myxedema coma.
liothyronine
For patients with Hashimoto thyroiditis or any form of hypothyroidism, _______ is the drug of choice.
levothyroxine
The side effects of levothyroxine are the symptoms of ______, namely, palpitations, diarrhea, weight loss, and increased appetite.
Hyperthyroidism
______ is a recombinant form of T4 that served as a thyroxine replacement and is an agonist at the thyroid hormone receptor.
Levothyroxine
Triiodothyronine has a (shorter/longer) ______ half-life than thyroxine.
shorter
A 20-year-old woman, gravida 1, para 0, is brought to the obstetrics clinic for her first prenatal visit. Patient’s medical history include diabetes mellitus type 1 and hypothyroidism controlled with levothyroxine. Levothyroxine is explained to the patient as a category A drug. Which of the following best describes a category A medication?
a) Positive evidence of human fetal risk that may or may not outweigh the potential benefit
b) Well-controlled studies in women fail to demonstrate a risk to the mother
c) Well-controlled studies in women fail to demonstrate a risk to the fetus in the first trimester
d) Clearly defined risk of fetal abnormality outweighing the potential benefit
e) Animal studies demonstrating adverse effects that are not supported by well controlled human studies
c) Well-controlled studies in women fail to demonstrate a risk to the fetus in the first trimester
A 25-year-old woman is brought to the dermatology clinic because of palpitations and hyperhidrosis of the palms and soles for the past month. Her temperature is 38°C (100.4°F), pulse is 106/min, respirations are 18/min, and blood pressure is 142/80 mm Hg. The patient’s medications include bupropion and levothyroxine. Which of the following physical examination findings are most consistent with this patient’s clinical picture?
a) Angular cheilitis
b) Hirsutism
c) Koilonychia
d) Plummer’s nails
e) Psoriasis
d) Plummer’s nails
