CAH/Kallman's/MD/PCD/ADPKD Flashcards
Definition of congenital adrenal hyperplasia?
Any one of several autosomal recessive diseases in enzymes catalyzing the production of mineralocorticoids, glucocortticoids or sex steroids from the adrenal glands
How do CAH affect sexual development?
Cause excessive or inadequate production of sex steroids
Commonest gene mutated in CAH?
21-hydroxylase
How does 21-hydroxylase mutation arise?
Recombination between the active CYP21A gene, and the homologous inactive pseudogene CYP21P. Process known as gene conversion
How do female infants with classic CAH present?
Ambigious genitalia due to androgen excess; less affected females may present with early pubarcge
How might young women present with CAH?
Symptoms of PCOS
Symptoms of males with classic CAH?
Generally none at birth; may present later with hyperpigmentation and possible penile enlargement
In males what does the age of diagnosis generally depend on?
Severity of aldosterone deficiency
How do males and females present in rarer forms of CAH?
Males- undermasculinzed
Females- no symptoms at birth
Autosomal dominant triplet repeat disorder causing inability to relax muscles?
Myotonic dystrophy
What tripet repeat is implicated in myotonic dystrophy and what genes?
CTG
Type 1- DMPK gene
Type 2- CNBP gene
Spectrum of disease in myotonic dystrophy
a) mild
b) classical
a) cataracts
b) frontal balding, heart defects, increased risk of diabetes
How does MD affect fertility?
Women can get POF, higher miscarriage rate. Men can get gonadal atrophy
Isolated gonatrophin-releasing hormone leading to hypogonadism, lack of sexual maturation and anosmia (lack of sense of smell)
Kallman syndrome
Why is Kallman syndrome difficult to counsel for?
Various modes of inheritance and many genes involved
