Intro Week Lectures 2 Flashcards
When during pregnancy is fetal growth the fastest?
Peaks in 2nd trimester
How fast should children grow normally?
Growth velocity 5-7cm/yr
Falls slowly to <5cm/yr pre-pubertally
mid-childhood spurt at 6-8 yrs
First sign of puberty in girls v boys?
Breast change in girls/testicular growth in boys (4 mls size)
Sign of completion of puberty in girls v boys?
menarche in girls/ 10 mls size testes in boys
What tools can you use to assess growth?
Leicester height measure (stadiometer), weighing scales, head circumference
Growth charts
Bone age
Prader orchidometer
Short stature with normal growth velocity suggests what?
constitutional delay
Often associated with medical conditions e.g. asthma
Delayed bone age
Later onset of puberty
Often familial, will eventually achieve genetic height potential
Causes of short stature with slow velocity?
Chronic disease - e.g. Coeliac
GH deficiency
Skeletal dysplasia
Syndromes e.g Turner, Down, Prader-Willi,
Endocrine e.g hypothyroidism, hypopituitarism, Cushings
Child abuse
How may isolated growth hormone deficiency present?
midline defects e.g. cleft lip and cleft palate
undescended testes
Questions to ask patient / parents with suspected Turner’s?
Lymphoedema of hands/feet in neonates
Congenital Heart Disease
Recurrent ear infections
Learning difficulties– coordination, numerical
Delayed puberty – primary amenorrhoea
How can Turner’s syndrome be managed?
Growth Hormone – supraphysiological doses
Pubertal hormones
Educational help
Hearing aid/grommets
Cardiac monitoring
Osteoporosis prevention
What conditions are screened for in newborn screening?
Phenylketonuria (PKU)
Congenital Hypothyroidism
Sickle Cell Disease (SCD)
Cystic fibrosis (CF)
Medium chain Acyl- CoA-dehydrogenase deficiency (MCADD)
Causes of tall stature in children?
Familial
Early / precocious puberty
Hyperthyroidism, GH secreting adenomas
Marfan’s, Klinefelters
How does Marfan’s syndrome present?
tall stature with arm span to height ratio > 1.05
high-arched palate
pes planus
arachnodactyly
pectus excavatum
lungs: repeated pneumothoraces
eyes: upwards lens dislocation
Define hypersensitivity
Objectively reproducible symptoms or signs following exposure to a defined stimulus (e.g. food, drug, pollen) at a dose which is tolerated by normal people
Define allergy
A hypersensitivity reaction initiated by specific immunological mechanisms, leading to disease. This can be IgE mediated or non-IgE mediated.
Allergy is not a disease, but a mechanism leading to a disease
Define atopy
A personal and/or familial tendency to produce IgE antibodies in response to ordinary exposures to potential allergens, usually proteins.
Strongly associated with asthma, rhinitis and conjunctivitis, eczema and food allergy.
Define anaphylaxis
Severe, potentially life-threatening generalised or systemic hypersensitivity reaction which is characterised by being rapid in onset, effecting airway, breathing or circulatory problems, and is usually associated with skin and mucosal changes.
How may anaphylaxis present in children?
Signs that are difficult to interpret: behavioural changes, fussing, irritable
hoarseness (after crying), drooling
regurgitation (common after feeds)
drowsiness, somnolence (after feeds)
Signs obvious but non-specific: rapid onset coughing, choking, stridor
sudden, profuse vomiting
rapid onset unresponsiveness
How do allergies develop?
Allergic diseases occur when individuals make an abnormal immune response to harmless environmental stimuli, usually proteins
The developing immune system must be ‘sensitised’ to an allergen before an allergic immune response develops.
Sensitisation may be ‘occult’ e.g. sensitisation to egg in from exposure to trace quantities in maternal breast milk.
Outline the process of mast cell activation in IgE mediated allergy
antigen binds to specific IgE
IgE releases mediators such as histamine, tryptase and prostaglandins
Describe onset and resolution of sxs in IgE mediated versus non-IgE mediated allergy
IgE : comes on within 2 hours, usually resolves within 12 hours
non-IgE: comes on hours or days post ingestion, may continue for days
Describe sxs in IgE mediated allergy
Gastrointestinal such as vomiting, pain and diarrhoea
Cutaneous such as urticaria, angiodema, pruritis
Respiratory such as acute rhinoconjunctivitis, wheezing, coughing, stridor
Cardiovascular such as collapse due to hypotension
Describe sxs in non-IgE mediated allergy
Often non-specific symptoms.
These can include diarrhoea, vomiting, colic/pain, blood in the stool, gastrooesophageal reflux and food refusal or aversion.
Give some examples of IgE-mediated clinical phenotypes
Acute urticaria and angioedema, anaphylaxis, oral allergy syndrome