Growth Disorders and Measurement Techniques

Growth Disorders

• Growth is an increase in cell size and number, resulting in height and girth changes
• Growth monitoring tracks a child's growth rate against established standards. It involves frequent anthropometric measurements
• Anthropometry measures a person's physical parameters and compares them to a standard
• Anthropometric measurements for weighing include essential pretesting, hanging the scale on a stable support, adjusting the dial to eye level, and ensuring the pointer is set to 0. The child should be undressed as much as possible, and their feet should not be touching the ground
• Measurement of length is used in infants and children up to 24 months old, while height measurements are appropriate for children 2 years or older.
• When measuring height, heels, buttocks, shoulder blades, and the occiput should lightly touch the measuring device. The head should be aligned so the external eye angle and external ear canal are horizontal, and the child should be looking straight ahead.
• Head circumference is a good measure of brain growth, especially during the first two years of life.
• Normal head circumference at birth is 34-36 cm.
• Head circumference increases by 2cm/month for the first 3 months, then 1cm/month for months 3-6, and 0.5cm/month for months 6-12. (12cm increase for the first year)
• Mid-upper arm circumference (MUAC) measures muscle development, correlates with malnutrition, and is efficient for screening large populations of 1-5 year olds (Shakir's tape)
• MUAC increases rapidly in the first year (11-16cm) and remains stable at 16-17cm for children 1-5 years old. Below 11.5cm indicates severe malnutrition.
• MUAC color coding: red (severe malnutrition - <11.0 cm), orange (moderate - 11.0 - 12.5 cm), yellow (at risk or mild - 12.5-13.5cm), green (well nourished - >13.5cm)
• Body mass index (BMI) is calculated by dividing weight (kilograms) by height squared (meters).
• Overweight: BMI between 85th and 94th percentiles
• Healthy weight: BMI between 5th and 85th percentiles
• Underweight: BMI below 5th percentile
• Normal BMI <25 kg/m², Overweight 25-29 kg/m², Obese ≥30 kg/m²
• Body mass index percentiles can be used to categorize children according to their weight status (underweight, healthy weight, overweight, or obese) based on age.
• Bone age assessment uses X-rays to determine the maturity of a child's bones and is useful in predicting the potential for future height. It correlates with sexual maturity.
• Calipers measure body fat. Body fat increases gradually with age.
• Flexibility is the range of motion about one or more joints. Flexibility is affected by the anatomical structure of the joint, exercise habits, stretching habits, age, and gender (women tend to be more flexible).
• Standard deviation (SD) measures the dispersion/variation of data values around the average. A low SD means data points are close together; a high SD means they are more spread out.
• Percentiles are used to summarize the distribution of values in a dataset, enabling comparison against the percentage of observations below a specific value.
• Growth charts track the growth of children over time against established benchmarks (percentiles).

Growth Chart Evaluation

• Assess if the child's height is below the 3rd percentile (or -2SD) in relation to his age and sex.
• Determine significant deficits in height compared to genetic potential (-2SD below mid-parental target).
• Assess if the child's growth velocity is abnormally slow
• Evaluate for dysmorphic features or disproportionate body features.
• Evaluate indications for GH deficiency or treatment (paediatric GHD and others)

Clinical Presentation of Growth Hormone Deficiency (GHD)

• The primary clinical manifestation of GHD is growth failure
• Congenital GHD causes: breech presentation, perinatal asphyxia, hypoglycemia, and prolonged jaundice
• Higher male to female ratio (3:1)
• Acquired GHD causes: growth failure, weight gain

Investigation and Management of Growth Hormone Deficiency

• GHD investigations include: measuring insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP-3), conducting provocative growth hormone (GH) testing, performing an MRI to assess pituitary and other brain structures, performing GH stimulation tests, and assessing IGF-1 and IGFBP-3 levels after GH stimulation.
• GHD management involves treating the underlying cause, providing psychological support if the cause is untreatable, and appropriate treatment for GH deficiency (e.g. paediatric GHD, Turner's syndrome, small for gestational age, chronic renal insufficiency, prader-Willi syndrome, AIDS cachexia)

GHD Complications

• Potential complications of GHD include increased intracranial pressure, impaired glucose tolerance, joint and muscle pain, carpal tunnel syndrome, pancreatitis, scoliosis, and an increased risk of neoplasm recurrence

Tall Stature

• Tall stature is characterized by height exceeding two standard deviations above the average for the population based on sex, age, and race. (Height > 2 SD)
• Common causes of tall stature include genetic, hormonal (GH excess, hyperthyroidism, excess androgen/estrogen), syndromes (Weaver Sotos Marfan Klinefelter), and metabolic disorders

Obesity

• Obesity is characterized by elevated body fat, often associated with health complications.
• General causes of obesity include high calorie intake, a lack of exercise, genetics, societal factors (personal choices), and diet
• Obesity is diagnosed using BMI (Body Mass Index) =weight(kg) / height² (m²), and BMI > 30 kg/m²
• Common measuring sites for body fat include: 2 sites on the trunk (sub scapular and supra iliac) and 3 sites on the extremities (triceps, thighs, and mid calf). TRICEPS is most reliable to obesity changes.

Microcephaly

• Microcephaly involves an abnormally small head size (HC < 2 Standard deviations below the mean for age and sex)
• It can be present at birth or during the first few years of life
• Common causes can be attributed to congenital problems, such as isolated, familial, X-linked, and chromosomal abnormalities. Acquired causes can include disruptive injuries, strokes, monozygotic twin demise, infections, TORCH infections (Zika virus), and drug exposure (fetal hydantoin syndrome, fetal alcohol syndrome).
• Other potential causes can include radiation exposure to the mother, poor maternal nutrition, poorly controlled gestational diabetes, hyperthermia, maternal hypothyroidism, and placental insufficiency.
• Potential associated issues can include intellectual disability, poor motor function, abnormal speech patterns, abnormal facial features, seizures, and dwarfism.

Macrocephaly

• Macrocephaly refers to an excessively large head in infants compared to the standards by age, sex, and race (HC > 2 standard deviations above the mean).
• Potential causes of macrocephaly can include hydrocephalus, brain malformations, brain tumors, intracranial bleeding, chronic hematomas, syndromes (Morquio syndrome, Hurler syndrome), and other risk factors such as Alexander disease, Canavan disease, and neurofibromatosis.
• Zika virus infection during pregnancy is another identified risk factor.

Precocious Puberty

• Precocious puberty is characterized by the acceleration of linear growth and earlier than expected skeletal maturation (bone age) for the child's chronological age.
• A consequence of precocious puberty is that the child's ultimate height may be stunted due to early epiphyseal closure.

General notes

• The use of appropriate growth charts is critical for assessment.
• The presentation may vary significantly between individuals.
• Specific investigations should be conducted based on clinical suspicion and findings.
• Consult with a healthcare professional for diagnosis and management.

This quiz explores growth disorders, emphasizing the importance of growth monitoring in children. It includes techniques for conducting anthropometric measurements, catering to various age groups for accurate growth assessment. Test your knowledge on best practices and standards for measuring height and weight in children.