Temporary Until Decks Synced Flashcards
What is first line bone maintenance treatment for patients on glucocorticoids?
Calcium and vitamin D supplementation
What do glucocorticoids do for bones?
Decrease intestinal absorption of calcium
Increase calcium excretion in urine
Accelerate bone resorption
How should treatments on glucocorticoids therapy for over three months (or 6 months if low dose, meaning <10mg/day) be monitored?
Baseline densitometry, and test repeated every year as long as therapy continues
What if a patient is on glucocorticoids and has very high risk of osteoporosis?
Add bisphosphonates (alendronate) to calcium and vitamin D supplementation
caution in premenopausal women bc of teratogenic risk
Sensitivity: definition + calc
The probability of a diseased person testing positive
Sensitivity = True positives / (True positives + False negatives)
Specificity: definition + calc
The probability of a nondiseased person testing negative
Specificity = True negatives / (True negatives + False positives)
Positive predictive value: def + calc
The probability that disease is present given a positive result
PPV = True positives / (True positives + False positives)
Negative predictive value: def + calc
The probability that disease is absent given a negative result
NPV = True negatives / (True negatives + False negatives)
Positive likelihood ratio: def + calc
A ratio representing the likelihood of having the disease given a positive result
LR+ = Sensitivity + (1-Specificity)
Negative likelihood ratio: def + calc
A ratio representing the likelihood of having the disease given a negative result
LR- = (1-Sensitivity) / Specificity
Diabetic ketoacidosis in children: clinical features
Polyuria/nocturia Polydipsia, polyphagia Vomiting, abdominal pain Weight loss, fatigue Kussmaul respirations (deep, rapid breathing) Dehydration
Diabetic ketoacidosis in children: laboratory findings
Glucose >200 mg/dL Bicarbonate <15 mEq/L PH <7.3 Anion gap >14 Serum/urine ketones
Diabetic ketoacidosis in children: management
10 mL/kg isotonic fluid bonus over 1 hour
Insulin infusion + isotonic fluids with potassium
Diabetic ketoacidosis in children: complications
Cerebral edema
How should one evaluate toxicity of a cardiotoxic agent such as doxorubicin or daunorubicin?
Radionucleotide ventriculograohy
Conditions that alter thyroxine-binding globulin (TBG): increased TBG
Estrogens (eg pregnancy, OCs, HRT) & estrogenic medications (eg tamoxifen)
Acute hepatitis
Conditions that alter thyroxine-binding globulin (TBG): decreased TBG
Androgenic hormones
High-dose glucocorticoids/hypercortisolism
Hypoproteinemia (eg nephrotic syndrome, starvation)
Chronic liver disease
What does thyroxine-binding protein (TBG) do?
More than 99% circulating thyroid hormone (T4, T3) is bound to TBG. Free thyroid hormone is cleared by the kidneys so TBG makes sure adequate hormone available for tissue delivery. Patients who start estrogen therapy need higher dose of levothyroxine to saturate the binding sites bc they develop relative hypothyroidism.
What do bile acid-binding resins (eg cholestyramine) do to intestinal levothyrozine absorption?
Decrease absorption.
Iron, fiber, antacids also decrease absorption.
What agents are used to treat thyrotoxicosis and thyroid storm, and through what mechanism?
Glucocorticoids, beta blockers, and proplythiouracil
They inhibit peripheral deiodination of T4 to T3.
What drugs and substances inhibit thyroid hormone secretion?
Lithium, potassium iodide, and Luton solution (elemental iodine and potassium iodide)
