ABP Pediatric Endocrinology flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Midparental height formula

Boys: (father's height + mother's height + 13 cm)/2; girls: (father's height + mother's height − 13 cm)/2. Target range is this value ±8.5 cm.

Growth hormone provocative testing

Two agents such as clonidine, arginine, glucagon, or insulin are used; a peak GH below about 10 ng/mL supports growth hormone deficiency, though assay-specific cutoffs vary.

Turner syndrome growth hormone

Girls with Turner syndrome may receive recombinant GH at doses up to 0.375 mg/kg/week divided daily, often started at 4-6 years, to improve adult height.

Pituitary hormone loss order

In acquired hypopituitarism growth hormone is usually lost first, followed by gonadotropins, TSH, ACTH, and finally antidiuretic hormone.

Craniopharyngioma presentation

Children present with headache, visual field defects, growth failure, obesity, and diabetes insipidus; treatment is surgery with or without radiotherapy, often causing panhypopituitarism.

Water deprivation test

Water deprivation concentrates urine in primary polydipsia but not in diabetes insipidus; desmopressin then concentrates urine in central but not nephrogenic diabetes insipidus.

Congenital hypothyroidism treatment

Start levothyroxine 10-15 mcg/kg/day immediately after confirmatory serum free T4 and TSH; do not delay for imaging, because early treatment preserves cognitive outcome.

Graves disease first-line drug

Methimazole is first-line for pediatric Graves disease; propylthiouracil is avoided in children because of hepatotoxicity but is used in thyroid storm and the first trimester.

Pediatric thyroid nodule workup

Any pediatric thyroid nodule is evaluated with TSH, ultrasound, and fine-needle aspiration if at least 1 cm; malignancy risk is higher in children than in adults.

Salt-wasting CAH findings

21-hydroxylase deficiency causes hyponatremia, hyperkalemia, hypotension, elevated 17-hydroxyprogesterone, and elevated renin; treat with hydrocortisone, fludrocortisone, and sodium chloride.

Adrenal crisis hydrocortisone dose

Give hydrocortisone 50-100 mg/m2 intravenously as a bolus, then 50-100 mg/m2/day divided, with isotonic saline containing dextrose for stress coverage.

Primary aldosteronism findings

Hypertension with hypokalemia, elevated aldosterone, and suppressed renin indicates primary aldosteronism; adrenal imaging and adrenal vein sampling may localize a unilateral adenoma.

GnRH agonist stimulation test

A pubertal LH peak above about 5 IU/L after GnRH agonist confirms central precocious puberty; a flat response suggests peripheral or prepubertal causes.

Delayed puberty definition

Absence of breast development by age 13 in girls, or no testicular enlargement by age 14 in boys, defines delayed puberty and warrants endocrine evaluation.

Klinefelter syndrome features

47,XXY causes small firm testes, gynecomastia, tall stature, elevated gonadotropins, and infertility; testosterone replacement supports virilization and bone health.

Complete androgen insensitivity

46,XY with female external genitalia, blind vaginal pouch, absent uterus, testes, and normal-to-high testosterone; androgen receptor mutations cause the complete form.

5-alpha-reductase deficiency

46,XY with low dihydrotestosterone and a high testosterone/DHT ratio; affected infants may have ambiguous genitalia and virilize at puberty.

Ambiguous genitalia newborn workup

Obtain karyotype, 17-hydroxyprogesterone, electrolytes, pelvic ultrasound, testosterone, and LH; delay sex assignment until congenital adrenal hyperplasia and other causes are excluded.

DKA initial fluid bolus

Give 10 mL/kg isotonic saline before insulin, then maintenance plus deficit; avoid rapid osmotic shifts and watch for cerebral edema with headache, bradycardia, and hypertension.

Neonatal diabetes genetics

Mutations in KCNJ11 or ABCC8 cause transient or permanent neonatal diabetes and often respond to oral sulfonylureas, allowing insulin discontinuation.

Hypoglycemia critical sample

At glucose below 50 mg/dL obtain insulin, C-peptide, cortisol, growth hormone, ketones, free fatty acids, lactate, ammonia, and acylcarnitine before treatment.

Nutritional rickets laboratory findings

Low 25-hydroxyvitamin D, low phosphate, high alkaline phosphatase, and elevated PTH with wrist metaphyseal cupping and fraying on radiographs characterize nutritional rickets.

Corrected calcium formula

Corrected calcium equals measured calcium plus 0.8 times (4.0 minus albumin in g/dL); use it when serum albumin is abnormal.

Pseudohypoparathyroidism features

Low calcium, high phosphate, and elevated PTH with GNAS mutations; Albright hereditary osteodystrophy includes short stature, round face, and brachydactyly.

Childhood obesity definition

BMI at or above the 95th percentile for age and sex defines obesity; 85th to 95th percentile is overweight, and 120% of the 95th percentile is severe obesity.

Familial hypercholesterolemia criteria

LDL cholesterol above 190 mg/dL suggests familial hypercholesterolemia; statins may be started from about 8-10 years after lifestyle counseling.

Metabolic syndrome criteria

Central obesity plus two of: triglycerides at least 150 mg/dL, HDL below 40 mg/dL, blood pressure at least 130/85, or fasting glucose at least 100 mg/dL.

SIADH diagnostic criteria

Euvolemic hyponatremia with urine osmolality above 100 mOsm/kg, urine sodium above 40 mEq/L, and low serum osmolality; treat with fluid restriction.

Hyponatremia correction limit

Raise serum sodium by no more than 8-10 mEq/L in 24 hours to avoid osmotic demyelination; use 3% saline only for symptomatic or severe hyponatremia.

MEN2B features

RET codon 918 mutations cause medullary thyroid carcinoma, pheochromocytoma, marfanoid habitus, and mucosal neuromas; early prophylactic thyroidectomy is recommended.

Beckwith-Wiedemann syndrome

11p15 imprinting defects cause macroglossia, omphalocele, macrosomia, neonatal hypoglycemia, and increased Wilms tumor and hepatoblastoma risk requiring screening.

Prader-Willi syndrome

Loss of paternal 15q11-q13 expression causes neonatal hypotonia, hyperphagia, obesity, hypogonadism, and short stature; growth hormone is often used.