Endocrine Cases (Pestana) Flashcards
A 62 year old lady was drinking her morning cup of coffee at the same time she was applying her makeup, and she noticed in the mirror that there was a lump in the lower part of her neck, visible when she swallowed. She consult you for this and on physical exam you ascertain that she indeed has a dominant, 2 cm. mass on the left lobe of her thyroid as well as two smaller masses on the right lobe. They are all soft and she has no palpable lymph nodes in the neck.
Management: Most thyroid nodules are benign, and surgical removal to ascertain the diagnosis is a big operation…thus surgery has to be reserved for selected cases. Worrisome features include: young, male, single nodule, history of radiation to the neck, solid mass on sonogram and cold nodule on scan. In center with sufficient experience, the last tow tests are omitted in preference for fine needle aspiration and cytology. This case does not sound malignant, but you can not be sure. If given the option among the answers, go for the FNA.
A 21 year old college student is found on a routine physical examination to have a singe, 2 cm. nodule in the thyroid gland. The young man had radiation to his head and neck when he was thirteen years old because of persistent acne. His thyroid function tests are normal.
Management: This one will need surgery, but if offered FNA is still your first answer.
A 44 year old lady has a palpable mass in her thyroid gland. She also describes losing weight in spite of a ravenous appetite, palpitations and heat intolerance. She is a thin lady, fidgety and constantly moving, with moist skin and a pulse rate of 105.
Management: confirm hyperthyroidism by measuring free T4. Confirm source of the excessive hormone with radioactive iodine scan. Do surgery after Beta blocking.
A 22 year old male has a 2 cm. round firm mass in the lateral aspect of his neck, which has been present for four months. Clinically this is assumed to be an enlarged jugular lymph node and it is eventually removed surgically. The pathologist reports that the tissue removed is normal thyroid tissue.
What is it? - There is no such thing as “lateral aberrant thyroid”. This is metastatic follicular carcinoma from an occult primary in the thyroid gland.
Management: Look for the primary with a thyroid scan. Eventually surgery.
An automated blood chemistry panel done during the course of a routine medical examination indicates that an asymptomatic patient has a serum calcium of 12.1 in a lab where the upper limit of normal is 9.5. Repeated determinations are consistently between 10.5 and 12.6. Serum phosphorus is low.
What is it? - Parathyroid adenoma.
How is the diagnosis made? - Had this question been written 20 years ago, the vignette would have described a patient with a disease of “stones and bones and abdominal groans”, and you would have cleverly asked for a serum calcium as your first test. Nowadays most parathyroid adenomas are identified when they are still asymptomatic, because of the widespread use of automated blood chemistry panels. Across the board most cases of hypercalcemia are due to metastatic cancer, but that would not be the case in asymptomatic people. Your next move here is PTH determination and sestamibi scan to localize the adenoma. Surgery will follow.
A 32 year old woman is admitted to the psychiatry unit because of wild mood swings. She is found to be hypertensive and diabetic and to have osteoporosis. (she had not been aware of such diagnosis beforehand). It is also ascertained that she has been amenorrheic and shaving for the past couple of years. She has gross centripetal obesity, with moon facies and Buffalo hump, and thin, bruised extremities. A picture from 3 years ago shows a person of very different, more normal appearance.
What is it? - Cushings. The appearance is so typical, that you will probably be given a photograph on the test, with an accompanying brief vignette. The presenting symptom may be any one of those listed.
How is the diagnosis made? - Start with AM and PM cortisol determinations. Later she will get dexamethasone suppression tests and MRI) of the head looking for the pituitary microadenoma, which will eventually be removed by the trans-nasal, trans-sphenoidal route.
A 28 year old lady has virulent peptic ulcer disease. Extensive medical management including eradication of H.Pylori fails to heal her ulcers. She has several duodenal ulcers in the first and second portions of the duodenum. She has watery diarrhea.
What is it? - Gastrinoma (Zollinger-Ellison).
How is the diagnosis made? - Start by measuring serum gastrin. Later CT scans (or MRI) of the pancreas looking for the tumor, and surgery to remove it.
A second year medical student is hospitalized for a neurological work-up for a seizure disorder of recent onset. During one of his convulsions it is determined that his blood sugar is extremely low. Further work-up shows that he has high levels of insulin in the blood with low levels of C-peptide.
What is it? - Exogenous administration of insulin. If the C-peptide had been high along with the insulin level, the diagnosis would have been insulinoma.
Management: In this case, psychiatric evaluation and counseling (He is faking the disease to avoid taking the USMLE). If it had been insulinoma, CT scan or MRI looking for the tumor in the pancreas, to be subsequently removed surgically.
A 48 year old lady has had severe, migratory necrolytic dermatitis for several years, unresponsive to all kinds of “herbs and unguents”. She is thin, has mild stomatitis and mild diabetes mellitus.
What is it? - Glucagonoma.
How is the diagnosis made? - Determine glucagon levels. Eventually CT scan or MRI looking for the tumor in the pancreas. Surgery will follow. If inoperable, somatostatin can help symptomatically and streptozocin is the indicated chemotherapeutic agent.
