What are examples of dismorphologies which often go together
Diff btwn MRI and CT
CT is a series of x-rays and is thus better for dense structures (e.g. bone, calcifications). MRI used RF (Radio Frequency) signals and is better used for high water and/or hydrogen content substances (e.g. tumors, soft tissue). Repeated CT scans increase cancer risk while MRI does not, but MRI is much more expensive.
Examples of autosomal dominant disorders
Treacher Collins syndrome
von Willebrand's disease
True or False - a child cannot have a particular autosomal dominant disorder if neither of the parents has it
FALSE - it can occur spontaneously!
__% of genetic disorders are multifactorial
Differentiate fetal alcohol syndrome from fetal alcohol effect
FAS: Mother drinks alcohol during first trimester - leads to postnatal growth deficiencies, microcephaly, skeletal and heatt defects and characteristic facies (epicanthial folds, thin upper lip)
FAE: Mother drinks alcohol after first trimester - leads to development and behaviour problems
What is Prader-Willi syndrome
Deletion of a subset of 15 genes (which are normally silenced on maternal copy of chromosome) leads to hyperphagia and obesity, hypotonia, hypogonadism and mild retardation. It's sister syndrome (genes in same region of paternal chromosome are silenced) is Angelman syndrome.
Frequency of Down syndrome
Mechanisms by which Down syndrome occurs in order of frequency
1) Non-disjunction during meiosis phase 1, thus each haploid cell ends up with 24 chromosomes (2 copies of one)
3)Mosaicism of trisomy 21
__% of Down syndrome victims have congenital heart problems
What is Turner syndrome and what are its physical characteristics?
45X (one missing X chromosome) - results in webbed neck, low-set ears, broad chest and sterility. Also associated with Celiac's disease and coarctation of aorta (feel pulse in groin and arm at same time - groin is weaker - also, can listen in 2nd intercostal space)
Triple test and how to interpret it
High AFP = neural tube defects
High hCG, low AFP, low UE3 = down syndrome
All low = trisomy 18 (Edwards syndrome)
Deletion on chromosome 7q11 - have a 'cocktail party personality.' 80% will have SVAS (SupraValvulaire Aortic Stenosis)
Cornelia de Lang syndrome
Caused by spontaneous mutations (because the Dutch are so spontaneous :-D
Everything is joined like Dutchies riding bikes while holding hands:
- eyebrows meet at midline
- 2nd & 3rd toes tend to be joined
- incurved 5th finger
Severe mental retardation and heart problems
Remember REPENTS at NOON:
Eyes (wide set & epicanthal folds)
Pulmonary valve stenosis
Ears (backwards rotated and low set)
Neck (excess skin & low hairline on back)
Testicles often don't descend (cryptorchidism)
Causes dwarfism, thus it is ironic that it is AUTOSOMAL DOMINANT! Caused by defect in FGF recepter 3 and comes from father's gene (due to older father)
Of uknown origin - think of Kabuki make-up, which is done by asians, so SLOTTED EYES with EPICANTHAL FOLDS. One puts makeup on with the fingers, so PROMINENT FINGERPADS, and Kabuki actors tilt their heads to the sides, so ASYMETRIC, LOW-SET EARS. HEART PROBLEMS are also associated with this syndrome.
Cardiac abnormalities (esp. tetralogy of Fallot)
Abnormal facies (square ears since book are SQUARE)
Thymic aplasia (leading to recurrent infections)
Hypocalcemia (malfunctioning parathyroid glands)
22 (is a number - the number you need to remember is that ~90% of mutations are de novo)
Risk factors for ADHD
Smoking, alcohol and stress during the pregnancy
Most important neurotransmitter in ADHD
Four medications used for ADHD and details
Remember the structure of cardohydrates:
Atoms are smallest - Atomoxetine (like atoms, not very exciting, not stimulating, no fear of abuse, continuous working)
Methyl means one Carbon - Methylfenidaat (comes in two doses - long and short action - and works 70% of time)
Tri means three Carbons - Tricyclische antidepressiva (no specific indication for ADHD, but sometimes used)
Dex sounds like 'Hex' which means six carbons - Dextroamfetamine - just like Methylfenidaat, but half of the kids who do not response to Methylfenidaat respond to Dextroamfetamine
Definition of epilepsy
Two or more epileptic attacks not brought on by fever, drugs, etc, in a year.
What is Hoover's sign
Used to determine if leg paralysis is somatoform or organic. Place hand under heel of normal leg and ask patient to try to move paralyzed leg. If leg is actually paralyzed, pressure will be felt on hand as patient attempts to raise leg. If not pressure is felt, paralysis is likely somatoform.
What is a somatoform disorder?
Disorder of mental origin which manifests itself in physical symptoms (e.g. somatoform paralysis of leg indicates leg paralysis resulting from mental issues as opposed to organic issues)
Four reflexes necessary for a baby to breastfeed
Define underweight, anorexia nervosa and obesity
Underweight: <85% of expected weight
Anorexia nervosa: BMI < 17,5
Obesity: BMI > 30
Percentage of people who will die from Anorexia Nervosa
What is Münchausen Syndrome by Proxy
Caregiver fakes or causes harm to other in order to get resulting attention
What is SPUTOVAMO
...it is designed to help determine if child abuse has occured.
Estimate for bladder size
(Age + 2)*30mL
Percentage of kids in Holland who experience childabuse at leaste once before the age of 18
What is FISH and what is it used for
Flourescent In Situ Hybridization - used to detect specific sequences or specific deletions (e.g. Williams, 22q11)
What is SNP array and what is it used for?
Single Nucleotide Polymorphism array - used to detect SNPs
What is Treacher Collins syndrome
AUTOSOMAL DOMINANT genetic defect due to mutation of gene on chromosome 5. Yields facial defects such as absent cheekbones, a small jaw and malformed ears.
1p36 deletion syndrome
Almost always de Novo mutation - causes motor, speach and developmental delays and HYPOTONIA
Triade of infantile epilepsy, characteristic EEG pattern and mental retardation (only two required for diagnosis). Originally published by Dr. West in observation of his son :-( MRI shows atrophy of neurons and inlargement of ventricles. Often accompanies 1p36 deletion syndrome.
What is a somatoform disorder?
A mental illness characterized by physical symptoms that suggest physical illness or injury
What is a converstion disorder?
A condition in which patients present with neurological symptoms such as numbness, blindness, paralysis or fits, without a neurological cause.
Medication given for ADHD
ALWAYS begin with psycho-education and meditation therapy
Methylphenidate (Ritalin) is first pharmaceutical choice (mechanism of action is UKNOWN)
Dexamfetamine (Adderall) also used
Medication given for behavioural disorders
1st choice: stimulants
2nd choice: neuroleptics (antipsychotics)
In cases of severe agression, antipsychotics become 1st choice