Endocrinology Flashcards
Criteria for short stature
Height below 1st percentile for age
Sex for height >2 SD below sex-adjusted mid-parent height
8 approved pediatric indications for recombinant hGH treatment
GH deficiency
Idiopathic short stature
SGA short stature
Turner Syndrome
Prader-Willi Syndrome
Noonan Syndrome
SHOX gene abnormality
Chronic renal failure before transplantation
Criteria for stopping GH treatment
- Decision by the patient that he/she is tall enough
- Growth rate <1 inch/yr
- Bone age >14 yr in Girls, >16 yr in Boys
Features of Wolfram syndrome
DI, DM, Deafness, Optic atrophy
most common primary brain tumors associated with Central DI
Germinomas
Pinealomas
Features of SIADH
Hyponatremia
Inappropriately concentrated urine
Normal/Slightly elevated Plasma volume
Normal/High Urine Sodium
Low Serum Uric Acid
Absence of:
Renal, adrenal, or thyroid insufficiency Heart failure, nephrotic syndrome, or cirrhosis Diuretic ingestion
Dehydration
Urine osmolality >100 mOsm/kg (usually > plasma)
Serum osmolality <280 mOsm/kg and serum sodium <135 mEq/L
Urine sodium > 30 mEq/L
Reversal of “sodium wasting”and correction of hyponatremia with water restriction
this is caused by rapid correction of hyponatremia
Central pontine myelinolysis
Most common brain lesion causing central precocious puberty
Hypothalamic hamartomas
Definition of precocious puberty
onset of secondary sexual characteristics before 8 yr in females, before 9 yr in males
most common cause of delayed puberty
constitutional delay of growth and puberty
physiologically active thyroid hormone
T3
- this is because it binds the thyroid hormone receptor with 10-15 fold greater affinity
most sensitive test for primary thyroid dysfunction
Serum TSH level
TSH levels are elevated in what condition
Primary Hypothyroidism
TSH levels are suppressed in what condition
Hyperthyroidism
State of insufficient circulating thyroid hormone
Hypothyroidism
most common cause of permanent congenital hypothyroidism
Thyroid Dysgenesis
Pendred syndrome is an autosomal recessive disorder composed of _____ and _____
Sensorineural deafness and Goiter
most common cause of congenital hypothyroidism worldwide
Endemic Goiter//Iodine Deficiency
true or false: congenital hypothyroidism, most babies are asymptomatic
true
anomalies most common in 10% of infants with congenital hypothyroidism
cardiac anomalies
features of untreated congenital hypothyroidism
stunted growth
short extremities
normal/increased head size
large anterior fontanel
open posterior fontanel
at what month of age is the clinical picture of congenital hypothyroidism will be fully developed
3-6 months of age
group of patients who deserve vigilance for congenital hypothyroidism
Infants with Trisomy 21 or with cardiac defects
treatment for congenital hypothyroidism
Levothyroxine (L-T4)
- Although T3 is the biologically active form of thyroid hormone, 80% of circulating T3 is derived from deiodination of circulating T4
recommended initial dose of L-T4
10-15 ug/kg/day
recommended monitoring of Serum T4/FT4 and TSH for patient with congenital hypothyroidism undergoing treatment
every 1-2 months in the 1st 6 months of life, then every 2-4 months between 6 months and 3 years of age
most common cause of acquired hypothyroidism
Autoimmune thyroid disease// chronic lymphocytic thyroiditis//hashimoto thyroiditis
examples of anticonvulsants which may cause thyroid dysfunction
Phenytoin
Phenobarbital
Valproate
This refers to any disorder that causes inflammation of the thyroid gland
Thyroiditis
difference between painful thyroiditis and painless thyroiditis
painful thyroiditis is typically due to infection or trauma whereas painless thyroiditis is often autoimmune-mediated or due to drug exposure
Differentiate Thyrotoxicosis from Hyperthyroidism
Thyrotoxicosis is a state of excess circulating thyroid hormone while Hyperthyroidism refers to the synthesis and secretion of excess thyroid hormone from the thyroid gland
most common cause of hyperthyroidism in children
Graves Disease
Peak incidence of Graves Disease
11-15 year old age group
Give precipitating events that lead to Thyroid storm
Trauma
Infection
RAI treatment
Surgery
Enumerate symptoms of Thyrotoxicosis
Constitutional: Weight loss despite increased appetite, heat-related symptoms (heat intolerance, sweating, polydypsia)
Neuromuscular: Tremor, nervousness, anxiety, fatigue, weakness, disturbed sleep, poor concentration
Cardiovascular: Palpitations
Pulmonary: Dyspnea, Shortness of breath
Gastrointestinal: Hyperdefecation, nausea, vomiting
Skin: Increased perspiration
Ocular: Diplopia, sense of irritation in the eyes; eyelid swelling; retro-orbital pain or discomfort
First line ATD for children with Graves disease, state its function
Methimazole
- blocks the organification of iodide necessary to synthesize thyroid hormone
Why is propylthiouracil not recommended in children as the first line treatment for Graves Disease?
It has a potential to cause LIVER FAILURE
Severe adverse reaction caused by ATDs
Agranulocytosis
Congenital malformations associated with exposure to Methimazole in utero
Aplasia cutis
Omphalocoele
Choanal atresia
Urinary System malformations
> 90% of Congenital Adrenal Hyperplasia is caused by
21-Hydroxylase deficiency
hormones deficient in CAH (severe salt-wasting form)
Cortisol
Aldosterone
Major function of Aldosterone
Maintain IV volume by conserving Na and eliminating K and hydrogen ions
typical laboratory findings in CAH
Hyponatremia
Hyperkalemia
Metabolic Acidosis
Hypoglycemia
Treatment of Cortisol deficiency
Glucocorticoids
result of abnormally high blood levels of cortisol or other glucocorticoids
Cushing Syndrome
most common etiology of endogenous Cushing syndrome in children older than 7 yr of age
Cushing disease
— excessive ACTH secreted by a pituitary adenoma causing bilateral adrenal hyperplasia
treatment of choice in pituitary cushing disease in children
Transsphenoidal pituitary microsurgery
Differentiate Type 1 and Type 2 DM
T1DM - results from deficiency of insulin secretion
T2 DM - results from insulin resistance
most common endocrine metabolic disorder of childhood and adolescence
Type 1 DM
susceptibility to T1DM is controlled by ____ expressing ____
Major Histocompatibility complex (MHC) - Human Leukocyte Antigens (HLAs)
How to diagnose DM?
FBS >= 126 mg/dL
2 hr plasma OGTT >= 200 mg/dl
hBA1C >= 6.5%
or
Symptoms of DM (polyuria, polydypsia, unexplained weight loss with glucosuria and ketonuria) + Random/casual plasma glucose >200 mg/dL
peaks of presentation of T1DM
5-7 yr of age and time of puberty
clearest evidence of a role of viral infection in human T1DM is seen in what condition
Congenital Rubella Syndrome
Classification of DKA based on pH
Mild: pH 7.25-7.35
Moderate: 7.15-7.25
Severe: pH <7.15
Expected electrolyte abnormalities in DKA
Hyponatremia
Hypokalemia
Hypophosphatemia
This electrolyte imbalance would also be classified as severe diabetic ketoacidosis
Severe hypernatremia >150 meqs/L
major cause of morbidity and mortality in children and adolescents with T1DM
Cerebral edema
in the event that cerebral edema develops in DKA, what are the immediate interventions to be done?
Elevation of the head of the bed
Reduction in IV fluid rate
Administration of Mannitol (1 g/kg) over 20 minutes
Current recommended blood glucose targets in DM
90-130 mg/dL before meal
90-150 mg/dL before bedtime
what is DAWN phenomenon?
caused by overnight growth hormone secretion and increased insulin clearance
criteria for testing Type 2 DM in children
Overweight +
any 2 of the ff risk factors:
- family history of T2DM in the first or 2nd degreee relative
- race/ethnicity (Native american, african american, hispanic, asian/pacific islander)
- Signs/conditions of insulin resistance (acanthosis nigricans, hypertension, dyslipidemia, PCOS)
recommended as the screening test for T2DM in children
Fasting Blood glucose
HbA1c target for all children with diabetes
<7.5%
Enumerate side effects of GH treatment
Pseudotumor cerebri
Slipped capital femoral epiphysis
Gynecomastia
Worsening of scoliosis
Coarsening of features
6-fold increase in the risk for type 2 diabetes
Medications that can cause acquired NDI
Lithium, Amphotericin B, Methicillin, Rifampin
diagnosis of diabetes insipidus is established thru what values of serum and urine osmolarity
Serum osmolarity >300 mOsm/kg
Urine osmolarity <300 mOsm/kg
most common primary brain tumors associated with DI
Germinomas
Pinealomas
oral dosage safe and effective in children with central DI
25-300 ug every 8-12 hours
this is a condition of precocious puberty with polyostotic fibrous dysplasia and abnormal pigmentation
McCune-Albright Syndrome
age of onset of McCune-Albright Syndrome in females
3-6 year
major cause of morbidity in McCune-Albright Syndrome
Fibrous dysplasia of multiple bones (polyostotic)
Definition of Delayed Puberty
failure of development of any pubertal feature by 13 yr of age in Females or by 14 yr of age in Males
most common cause of delayed puberty and is thought to be a normal variant
Constitutional delay of growth and puberty
cardinal diagnostic result in Constitutional delay of growth and puberty
Bone age that is moderately delayed in comparison with chronologic age
mechanisms underlying delayed TSH elevation and apparent transient primary hypothyroidism in preterm infants
- immaturity of hypothalamic-pituitary-thyroid axis
- loss of the maternal contribution of thyroid hormone normally present in 3rd trimester
- severe illness and complications of prematurity
- exposure to medications that can affect thyroid function
presence of this sign at birth may be a clue to early recognition of congenital hypothyroidism
Anterior and posterior fontanels are open widely
Most common form of hypogonadotropic hypogonadism
Kallmann syndrome
— associated with anosmia or hyposmia, short stature, ocular albinism
Levothyroxine tablet should not be mixed with these 3 substances because they can inhibit its absorption
Soy protein formulas
Concentrated Iron
Calcium
most common infectious etiology for adrenal insufficiency
Meningococcemia
—Waterhouse-Friderichsen syndrome: adrenal crisis
hBa1C target for all patients with T1DM
<7.5% should be considered but individualized
childhood tumor associated with Beckwith-Wiedemann syndrome
Wilms tumor
Neuroblastoma
Hepatoblastoma
components of metabolic syndrome
Central obesity
Hypertension
Glucose intolerance/impaired glucose
Hyperlipidemia
low HDL
