Familial glucocorticoid deficiency: Glucocorticord deficiency results in increased pituitary production of
ACTH, which has melanocyte-like stimulatory hormone properties. The combination of normal blood pressure and
normal-appearing genitalia in a female patient helps exclude adrenal
hyperplasias, which would present much earlier in life (usually in the
first month). This familial autosomal recessive disorder does not have salt
wasting as a feature and is due in some patients to defects in the ACTH
receptor.
·
Lipoid adrenal
hyperplasia is a rare disorder, reported in fewer than 100, mostly
Japanese patients. There is marked accumulation of cholesterol and lipids in
the adrenal cortex and gonads, associated with severe impairment of all
steroidogenesis. MUTATION IN STAR.
Genetic males are unable to synthesize androgens and
thus are phenotypically female but with gonads.
Genetic females appear normal at
birth and may undergo feminization at puberty with
menstrual bleeding. They too, however, progress to hypergonadotropic
hypogonadism when accumulated cholesterol kills granulosa (i.e.,
steroid-synthesizing) cells in the ovary.
·
Malignant adrenal tumor: A 4-yr-old previously normal girl has developed
acne and pubic hair. On physical examination she has clitoromegaly and mild
increase in her blood pressure. Serum dehydroepiandrosterone sulfate is
markedly elevated.
·
McCune-Albright syndrome is a
polyendocrinopathy with excessive hormone production. Precocious
puberty that is independent of central gonadotrophic hormones is
classic. Additional features include fibrous dysplasia and cutaneous
hyperpigmentation.
·
Apparent mineralocorticoid excess (11 -HSD
deficiency): The hypokalemic alkalosis in a hypertensive patient
without abnormal genitalia or sexual precocity is highly suggestive of a
primary disorder of mineralocorticoid excess.
·
Glucocorticoid-remediable
aldosterone is caused by Formation of a hybrid
gene between CYPI IB1 and CYPIIB2. This unique
mechanism explains the suppressibility of the
hyperaldosteronism, with one gene regulating the other.
·
Facial anomalies, especially if short stature is present, suggest pituitary
and thus growth hormone deficiency.
·
Most patients
with SOTOS syndrome have some degree
of mental retardation. Perceptual deficits are also common.
·
In the absence of neurologic or visual signs, a pituitary or hypothalamic
lesion is highly unlikely.
·
To Dx Congenital Hypothyroidism, T4 level should be done as TSH will
be low always.!!
·
Anti-GAD antibodies, also
known as anti-islet antibodies, are present in at least 90% of children with
insulin-dependent diabetes.
·
Neonatal
thyrotoxicosis normally is a self-limited disease that subsides by
about 3 months of age when maternal TSIs are metabolized. However, tachycardia,
irritability, and poor weight gain require treatment with low-dose PTU with or
without propranolol. The danger of treatment is oversuppression of the neonatal
thyroid and consequent hypothyroidism.
·
StAR protein
is necessary for proper reduction of aldosterone, cortisone, and sex hormones.
Its absence leads to feminization of males as part of congenital lipoid adrenal
hyperplasia. In a subset of patients with congenital lipoid adrenal
hyperplasia, mutations in StAR protein result in severe impairment of steroid
biosynthesis in the adrenal glands and gonads.
·
Circadian rhythms
do not affect the level of cortisol in very premature infants.
Infants with extremely low birth weight may have quite low cortisol levels (9.2
± 9.8 µg/mL) and lack the typical early-morning rise in cortisol. Whether such
low corticosteroid levels in premature infants with very low birth weight
indicate adrenal insufficiency is not fully known.
·
Even with
bilateral adrenal hemorrhage, most infants are asymptomatic.
·
Hypoglycemia and
microphallus are commonly presenting symptoms and signs of neonatal
hypopituitarism.
Midline facial defects
are associated with pituitary hormone deficiencies.
Placental growth hormone is secreted only into the
maternal circulation.
·
Sex-determining
region of Y-chromosome (SRY) is thought to be the first in a cascade
of transcription factors that initiate the process of testicular development.
SRY is located on the short arm of the Y chromosome, and the gonad loses
bipotentiality at approximately 6-8 weeks' gestation. In the absence of SRY
expression, the bipotential gonad will develop into an ovary.
·
Tandem mass
spectrometry (MS-MS) can be performed on dried blood spots and can
measure hundreds of metabolites to facilitate screening of dozens of inborn
errors of metabolism while more precisely quantitating the levels of the
metabolites to improve screening sensitivity and specificity.
·
There is no
difference between the units torr and mmHg.
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