Approach to tall

stature.

By: Dr Inayat Ullah.

PGY-II Pediatrics Shifa International Hospital Islamabad

Definition.

• Tall stature is defined as height beyond 97th

percentile (i.e., over two standard deviations)

of mean for age and sex.

•

• Excessive growth is defined as an abnormally

rapid growth velocity, which could manifest as

height acceleration across two major percentile

lines on the growth chart.

Growth charts.

• Height charts

• Weight charts

• BMI charts

• Proportionate charts

– Sitting height

– Sub-ischial leg length

• Growth velocity charts.

Predictors of height.

• Genetics, nutrition, hormones (growth hormone,

thyroid hormone, estrogen and testosterone) and

overall health.

• The growth spurt around puberty occurs around

2 years earlier in girls when compared to boys,

but the boys tend to be taller when it begins.

Height Predictors (MPH)

• Mid-parental height (MPH):

• Target height for boy = ([Father’s height + 13] + Mother’s height)/2 cm.

• Target height for girl = (Father’s height + [Mother’s height – 13])/2 cm.

• MPH is an indicator of child’s genetic potential for growth. The value is plotted as adult height at 18 years and the target range is 6 cm on either side of the target height (TH). This becomes the target range and if the child’s height is within these percentiles, it is considered as normal.

Regulation of growth

Normal human growth can be divided into three

overlapping stages each under the control of different

factors:

1. Infancy:

o Largely under nutritional regulation

o Wide inter-individual variation in rates of growth

o Many infants show significant ‘catch-up’ or ‘catch-

down’ in weight and length

o By 2 years, length is much more predictive of final

adult height than at birth

Regulation of growth

2. Childhood:

o Growth hormone (GH) and thyroxine

o Mini-growth spurts with intervening stasis, each phase lasting

several weeks

o Over years, a child will tend to maintain their centile position

on height charts, with a height velocity between the 25th and

75th centiles

3. Puberty:

o The combination of GH and sex hormones promotes bone

maturation and a rapid growth acceleration or ‘growth spurt’.

o In both sexes, oestrogen eventually causes epiphyseal fusion,

resulting in the attainment of final height.

Assessment of growth

• To minimize error in the calculation of height

velocity (cm/year), height measurements should be

taken

• at least 6 months apart

• using the same equipment and

• Ideally by the same person.

Height measurements

• From birth to 2 years

old, supine length is

measured ideally using

a measuring board (e.g.

Harpenden

neonatometer).

• Two adults are needed

to ensure that the child

is lying straight and legs

extended.

Height measurements

• From 2 years old, standing height is

measured against a wall-mounted or

free-standing stadiometer

• Without footwear

• Heels & back touching the wall

• Looking straight ahead

• Gentle but firm pressure upwards

applied to the mastoids from underneath

• US / LS ratio

• Horizontal Arm span

Etiology of Tall Stature.

• Familial:

– (constitutional) tall stature common cause

• Nutritional:

– Exogenous obesity.

• Endocrine:

– Precocious puberty (early stage), pituitary gigantism,

McCune-Albright syndrome, thyrotoxicosis,

androgen/estrogen deficiency, estrogen resistance (in

males), testicular feminization, adrenocorticotropic

hormone (ACTH)/cortisol deficiency, ACTH/cortisol

resistance and aromatase deficiency.

Etiology (cont’d)

• Chromosomal:– Klinefelter syndrome (XXY), fragile X syndrome, XYY

syndrome.

• Collagen vascular:– Marfan syndrome.

• Metabolic:– Homocystinuria.

• Fetal overgrowth syndrome:– Maternal diabetes mellitus, cerebral gigantism (Sotos

syndrome), Beckwith-Wiedemann syndrome, Weaver syndrome, Simpson-Golabi-Behmel overgrowth syndrome, other (IGF)-2 excess syndrome.

Causes of tall stature

• Familial Tall Stature:

• Most common cause of tall stature seen in

childhood and adolescence.

• Length of the child may be above average at

birth.

• History of a very tall parent or a close relative

Marfan’s Syndrome.

Marfan syndrome:

Hypotonia, joint laxity (thumb sign and wrist sign), lax skin,

ectopia lentis, abnormally flat cornea, blue sclera, iridodonesis,

Marfan's syndrome

arachnodactyly, dolichocephaly,

malar hypoplasia, retrognathia,

downslanting palpebral fissures,

high arched palate, crowding of

teeth, pectus excavatum or

carinatum, scoliosis,

aortic aneurysm, aortic

regurgitation, mitral valve

prolapsed

Homocystinuria:

• Ectopia lentis, cataracts,

• Arachnodactyly,

• Pectus excavatum or carinatum,

• Genu valgum, pes cavus,

• High arched palate,

• Scoliosis,

• Crowding of teeth

Klinefelter syndrome

• Gynecomastia, small testes,

• Sparse facial hair,

• Micropenis,

• Delayed pubertal development,

• Cryptorchidism,

• Hypospadias

• Thin and tall for age

• Low upper/lower segment ratio (long legs)

The XYY Syndrome

• Newborns are normal

• Many adult males are normal

• Tall stature, hypospadias and/or cryptorchidism, severe acne, radio-ulnarsynostosis

• Mild or moderate mental retardation, but findings of an XYY karyotype in newborn does NOT predict intelectual function

Sotos Syndrome =

Cerebral Gigantism• Unknown etiopathogenesis

• Transmitted AD & AR

• Large at birth (W&H), rapid growth in first year of life, above 97% for height at 1 year of age

• Rapid growth in first 3-4 years

• Arm span > 5cm above height (normally negative up to age 12 years)

• Irritability, feeding problems, delayed developmental milestones (esp. impaired fine motor control), IQ around 70.

• Mildly dilated cerebral ventricles, sometimes abnormal EEG,

• Poor intelectual prognosis

• Supposed to be at risk for hepatic neoplasm

Beckwith-Wiedemann syndrome• Hepatosplenomegaly,

• Nephromegaly,

• Macrososmia,

• Macroglossia,

• Omphalocele,

• Renal malformations,

• Ear creases/pits,

• Facial nevus flammeus

• Post natal gigantism and asymmetry: high risk for wilm’s tumor.

• Transient hyperinsulinemia and hypoglycemia

Diagnostic triad at birth

Omphalocele

Visceromegaly

Mc-Cune Albright Syndrome

• Polyostotic Fibrous Dysplasia

• Café au lait spots, irregular border, unilateral

and asymmetrical

• Endocrinopathies,most common

Hyperthyroidism and Precocious Puberty

Weaver syndrome

• Broad forehead and face,

• Ocular hypertelorism,

• Prominent wide philtrum,

• Micrognathia,

• Deep horizontal chin groove,

• Deep-set nails

Simpson-Golabi-Behmel syndrome

• Large protruding jaw,

• Widened nasal bridge,

• Macroglossia,

• Upturned nasal tip,

• Coarse face, ‘bulldog-like’ appearance, supernumerary nipples,

• Generalized muscular hypotonia, congenital heart defect

Physical Examination

• Meticulous measurement of parameters height, weight, BMI, upper segment/lower segment ratio, arm span and height/arm span ratio is essential.

• Accurate plotting of anthropometric parameters on growth chart

• Crossing height percentiles between infancy and onset of puberty always warrants further evaluation.

• Specifically look for signs of obesity, signs of precocious or delayed puberty, dysmorphism, stigmata of specific disorders known to be associated with tall stature.

• Tanner sexual maturity rating (SMR) should be done in all children presenting with tall stature as a routine practice..

MANOEUVRES TO ASSES FOR

TALL STATURE

• HANDS AND FEET TOGETHER:• Hemihypertrophy

• Unilateral growth arrest

• Genu valgum

• Genu recurvatum

• Pes planus

MANOEUVRES (cont’d)

• Bend over and touch toes:

– Scoliosis (Marfan, homocystinurea,sotos,NF-1)

– Kyphosis (with scoliosis as above, pituitary

gigantism)

MANOEUVRES (cont’d)

• Mobility:

– Hyper mobility (Marfan's)

– Limitation of extension (homocystinuria)

• Arachnodactyly

– To detect marfan’s syndrome.

• Tremors:

– To detect hyperthyroidism.

Investigation

MANAGEMENT

TREATMENT

• Reassurance of the family and the patients is

the key to the management of normal variant

tall stature.

• The use of the bone age and a careful

assessment of pubertal status to predict adult

height

• General supportive discussions on the social

acceptability of this condition

TREATMENT (Cont’d)

• Even though treatment is available for girls and boys with excessive growth.

• Its use should be restricted to patients with:

– Predicted adult height > 3 SD above the mean (78 inches or 198 cm in male patients, 71 inches or 180 cm in female patients) and

– Evidence of significant psychosocial impairment.

Treatment

• For those with extreme tall familial height or those with Marfan’s syndrome

• Sex steroid will cause early epiphyseal fusion and growth arrest and will accelerate puberty

• Oral ethinyl estradiol at a dose of 0.15-0.5 mg/24 hr until cessation of growth occurs has been used successfully in girls. If necessary, a progestational agent can be added after 1 year of unopposed estrogen.

• In boys, treatment should begin before the bone age reaches 14 yr; testosterone enanthate is used at a dose of 500 mg IM every 2 wk for 6 mo

Treatment of growth hormone oversecretion.

• The goals of therapy:– to remove or shrink the pituitary mass,

– to restore GH and secretory patterns to normal,

– to restore IGF-I and IGFBP-3 levels to normal,

– to retain the normal pituitary secretion of other hormones, and to prevent recurrence of disease.

• For well-circumscribed adenomas, transsphenoidal surgery The likelihood of surgical cure depends greatly on the surgeon's expertise as well as on the size and extension of the mass

• The goal of treatment: – Normalize GH levels.

– GH levels (<1 ng/mL within 2 hr after a glucose load) and serum IGF-I levels (age adjusted normal range) are the best tests to define a biochemical cure.

• If surgery fails to normalize growth hormone level:

– Medical theraphy

– Radiation

• Tumor growth is arrested in 99 % cases by radiations but it has delayed efficacy in lowering GH level

• Hypopituitarism is predictable outcome in 40-50 % cases after 10 yr irradiation.

Medical management

• Somatostatin analogs: highly effective in the treatment of patients with GH excess.– Octreotide suppresses GH to less than 2.5 ng/mL in 65%

of patients with acromegaly and normalizes IGF-I levels in 70%

• For cases that have both GH and prolactin oversecretion, dopamine agonists, such as bromocriptine, should be considered which bind to pituitary dopamine type 2 (D2) receptors and suppress GH secretion

• It is generally used as adjuvant medical treatment for GH excess. Its effectiveness may be additive to that of octreotide.