Paediatrics

Question 1

Turner syndrome definition

Answer 1

Turner syndrome occurs when a female has a single X chromosome (45XO)

Question 2

Turner syndrome presentation

Answer 2

Short stature
Webbed neck
High arched palate
Downward sloping eyes with ptosis
Broad chest with widely spaced nipples
Cubitus valgus (when the arm is extended downwards with the palms facing forward, the angle of the forearm at the elbow is exaggerated, angled away from the body)
underdeveloped ovaries
Late/incomplete puberty
Infertility

Question 3

Turner syndrome complications

Answer 3

Recurrent UTIs
Recurrent otitis media
Coarctation of aorta
Bicuspid aortic valve
Hypothyroidism
Hypertension
Obesity
Diabetes
Osteoporosis
Learning disabilities

Question 4

Turner syndrome management

Answer 4

Growth hormone therapy - prevent short stature
Oestrogen and progesterone replacement for female secondary sex characteristics
Fertility treatment

Question 5

Klinefelter syndrome definition

Answer 5

Male with an additional X chromosome (47 XXY)

Rarely, can present with further X chromosomes e.g. 48 XXXY or 49 XXXXY

Question 6

Klinefelter syndrome presentation

Answer 6

Usually appear normal till puberty

Taller height
Wider hips
Gynaecomastia (developing breasts)
Weaker muscles
Small testicles
Reduced libido
Shyness
Infertility
Subtle learning difficulties

Question 7

Klinefelter syndrome management

Answer 7

Testosterone injections for symptomatic relief
Advanced IVF to aid fertility
Breast reduction
Speech and language therapy
Physiotherapy
Educational support

Question 8

Klinefelter’s complications

Answer 8

Increased risk of

Breast cancer (less than women, more than XY men)
Osteoporosis
Diabetes
Anxiety & depression

Question 9

Down’s, Edward’s & Patau syndromes definition

Answer 9

Down’s = trisomy 21
Patau = trisomy 13
Edward’s = trisomy 18

Question 10

Down’s syndrome presentation

Answer 10

Hypotonia
Brachycephaly (small head with flat back)
Short neck
Short stature
Flattened face & nose
Prominent epicanthic folds
Upwards sloping palpebral fissures (gaps between lower and upper eyelid)
Single palmar crease

Question 11

Down’s syndrome complications

Answer 11

Learning disability
Recurrent otitis media
deafness
Visual problems
Hypothyroidism
Cardiac defects
Atlantoaxial instability
Leukaemia more common in children
Dementia more common in adults

Question 12

Down’s sydrome screening

Answer 12

11-14 weeks: combined test (nuchal translucency [>6mm], beta-HCG [high], PAPPA [low])

14-20 weeks: triple (beta-HCG [high], AFP [low] and serum oestriol [low]) or quadruple (same as triple plus inhibin A [high])

Question 13

Antenatal testing for Down’s syndrome

Answer 13

Chorionic villus sampling (<15 weeks) - ultrasound guided biopsy of placental tissue

Amniocentesis (later in pregnancy) - ultrasound guided aspiration of amniotic fluid

Question 14

Robertsonian translocation definition

Answer 14

Translocation (portion of one chromosome directly swapped with another) in acrocentric chromosomes (13, 14, 15, 21, 22). They have a long and short arm, and lose the short arm completely, with the two long arms joining

They are usually phenotypically normal but have 45 chromosomes and risk issues in their offspring

Question 15

Congenital adrenal hyperplasia definition

Answer 15

Group of inherited genetic disorders (autosomal recessive) caused by enzyme deficiencies in the adrenal cortex, disrupting steroid hormone synthesis

Most common variant is 21-hydroxylase deficiency

Question 16

Congenital adrenal hyperplasia presentation

Answer 16

Varies greatly depending on type and severity of enzyme defect

Typical features:

Ambiguous genitalia (esp in females due to in utero exposure to excessive androgens)
Hypotension
Salt wasting crises (low Na, high K, dehydration, shock & metabolic acidosis)
Vomiting
Virilisation (developing male secondary sexual characteristics)
Precocious puberty (males)

Question 17

Congenital adrenal hyperplasia investigations

Answer 17

Blood test hormone assays - low cortisol and elevated 17-hydroxyprogesterone suggest CAH
Genetic testing
Imaging

Question 18

Congenital adrenal hyperplasia management

Answer 18

acute treatment e.g. fluid & sodium replacement and hydrocortisone
Long-term hydrocortisone/fludrocortisone as needed
Patient education
Surgical intervention

Question 19

Androgen insensitivity syndome definition

Answer 19

Difference in sex development involving hormonal resistance androgen receptor dysfunction affecting biological men (XY)

Question 20

Precocious puberty definition

Answer 20

Early onset puberty
<8yrs in girls and <9yrs in boys

First signs of pubertal maturation are breast budding in girl and testicular volume >4mm in boys

Usually idiopathic in girls and pathological in boys

Question 21

Forms of precocious puberty

Answer 21

Gonadotropin dependent (central precocious puberty)
Gonadotrophin independent (peripheral or pseudo precocious puberty)
Abnormal pattern of gonadotrophin secretion (variants of early sexual maturation)

Question 22

Causes of central precocious puberty

Answer 22

Brain tumours (e.g. gliomas, germ cell tumours secreting HCG)
Hypothalamic hamartomas
Neurosurgery
Head injuries
Radiation therapy
Previous meningitis
Abscess
Congenital abnormalities

Question 23

Causes of gonadotrophin independent/non-central precocious puberty

Answer 23

Congenital adrenal hyperplasia
McCune Albright syndrome
HCG secreting tumours
Adrenal, ovarian, testicular cancers
Aromatase excess syndromes
Exposure to exogenous sex steroid hormones

Question 24

McCune Albright syndrome definition and presentation

Answer 24

GNAS gene mutation

Polyostotic fibrous dysplasia
Cafe-au-lait skin pigmentation
Autonomous endocrine hyperfunction

Question 25

Delayed puberty definition and types

Answer 25

Onset of puberty >13yrs in girls and >14 years in boys Constitutional delay (normal puberty just delayed) Secondary Hypogonadism (hypogonadotropic hypogonadism or hypergonadotropic hypogonadism)

Question 26

Hypogonadism examples

Answer 26

Hypogonadotrophic hypogonadism: Isolated gonadotrophin deficiency Multiple pituitary hormone deficiency Secondary to CNS tumours or cranial irradiation or congenital malformation Hypergonadotrophic hypogonadism: Turner’s Syndromes and Klinefelter’s Idiopathic gonadal failure/ autoimmune Secondary to TBI, Abdominal Dx and chemotherapy Rare disorders e.g. FSH receptor mutations

Question 27

Delayed puberty investigations

Answer 27

Clinical assessment of pubertal development Hand-wrist x-ray to assess bone age LH/FSH, thyroid hormones, oestrogen, testosterone

Question 28

Hypogonadotropic hypogonadism definition/example

Answer 28

Low levels of gonadotrophins (LH/FSH) and sex hormones e.g. Kallmann syndrome: X-linked recessive disorder, failure of GnRH-releasing neurons to migrate into the hypothalamus during development Similar phenotype to Klinefelter's but with a lack of colour vision and struggle with smell

Question 29

Hypergonadotropic hypogonadism definition/example

Answer 29

High levels of gonadotrophins (LH/FSH) and low levels of sex hormones e.g. Klinefelter's, Turner's syndrome

Question 30

Prader-Willi syndrome definition

Answer 30

Genetic disorder resulting from genetic imprinting, particularly affecting a gene on chromosome 15 (15q11-q13 region) The child only expresses the maternally inherited version of the gene

Question 31

Prader-Willi syndrome presentation

Answer 31

Hypotonia Poor feeding in infancy Developmental delay Short stature Learning disabilities Excessive hunger

Question 32

Angelman syndrome definition

Answer 32

Genetic disorder resulting from genetic imprinting, particularly affecting a gene on chromosome 15 (15q11-q13 region) The child only expresses the paternally inherited version of the gene

Question 33

Angelman syndrome presentation

Answer 33

Fascination with water Happy demeanour Inappropriate laughter Hand flapping Epilepsy ADHS Wide mouth with widely spaced teeth Severe delay/absence of speech development Microcephaly

Question 34

5a-reductase deficiency definition

Answer 34

Autosomal recessive genetic disorder affecting biological males in which 5a-reductase is defective or absent Enzyme usually converts testosterone to dihydrotestosterone, a more potent form of the hormone

Question 35

5a-reductase deficiency presentation/mechanism

Answer 35

5aR catalyzes the conversion of testosterone to DHT, which plays a key role in sexual differentiation of the genitalia and prostate during fetal development Atypical genitalia Hypospadias Micropenis Normal internal structures Testes undescended

Question 36

Androgen insensitivity syndrome definition

Answer 36

X linked disorder in which androgen receptor are dysfunctional (loss of function mutation), clinically significant only in XY males Can be complete, presenting with female external genitalia, mild when the external genitalia are male, or partial, where the external genitalia are partially masculinised

Question 37

Androgen insensitivity syndrome presentation

Answer 37

Internal, undescended testes (due to Y chromosome) Short vagina or under-masculinised genitalia Partial/complete regression of Mullerian structures 46XY karyotype Normal or elevated testosterone, LH, and oestrogen