Growthand growth issues and normal growth pattern.pptx

Growth related issues and growth patterns

1. Growth Growth refers to an increase in physical size of the whole body or any of its parts. It is simply a quantitative change in the child ’ s body. It can be measured in Kg, pounds, meters, inches, … .. etc

2. GROWTH PATTERN: Growth is characterized by phases of rapid growth ( intrauterine , infancy and puberty ) interspersed with reduced growth ( childhood ) Maximum linear growth happens in the fetal period with increase of 50 cm . Fetal growth is regulated by intrauterine environment with limited impact of growth hormone and thyroxine . Infancy is associated with gain of 25 cm in first year and 12 cm in the second. Growth during this period is largely driven by nutrition .

3. Childhood growth contributes significantly to adult height and occurs at a steady rate of 5-6 cm per year . Puberty accounts for 20-25 cm of growth . . 

4. Growth hormone Growth is regulated by the GHRH - GH - IGF1 axis with inputs from nutritional signals , sex steroids and thyroxine .  Growth hormone - IGF1 axis  Hypothalamic GHRH acts on pituitary to produce growth hormone . Growth hormone is secreted in pulsatile fashion with maximum release at night . Growth hormone acts on the liver to produce IGF I , which acts on the type I IGF receptor on the growth plate to induce growth . 

5. GROWTH REGULATION  Final height is determined by genetics explaining 60-80 % variation . Within this framework growth represents an interaction of nutrition and endocrine factors . Nutrition plays vital role in growth regulation . Type 1 nutrients ( vitamins , calcium , iodine and magnesium ) play a role in specific processes . There deficiency disrupts a unique facet with normal overall growth . Type II nutrients are the building blocks of body ( proteins , electrolytes , zinc , phosphorus and sulfate ) . Their deficiency causes global reduction in growth . 

6. Nutritional influence  Malnutrition is a growth hormone resistant state with high GH and low IGF1 levels. GHD may therefore be missed in children with malnutrition . Overnutrition is a growth hormone sensitive state with high IGFI and low growth hormone levels . This may lead to erroneous diagnosis of growth hormone deficiency in obesity. Increased insulin in obesity stimulates growth by raising free IGF1 levels and acting on the type I IGF receptor .

7. Growth assessment Growth assessment involves measurement of length and weight along with monitoring of growth velocity. Regular monitoring is mandatory to ensure early identification of growth disorders. When to assess growth? Growth should be assessed at each outpatient visit irrespective of the presenting complaint. Routine growth assessment is indicated at birth, at each immunization visit (6, 10 and 14 weeks), six months of age, six-monthly for the ages 1-8 years and annually thereafter.

8. Growth failure Growth failure is one of the most common presentation to a pediatrician . Most short children have physiological causes not requiring evaluation . The aim of evaluation of growth failure is to avoid unnecessary work - up in children with physiological causes while not missing a pathological cause . 

9. ETIOLOGY  Growth is controlled by multiple factors and abnormality in any of these may cause growth failure .

10. MANAGEMENT  Growth hormone therapy is indicated in children with: GHD ( benefit of 20-25 cm ) , Turner syndrome ( 10-15 cm ) , SGA without catchup ( gain 7-10 cm ) , chronic kidney disease planned for renal transplant and Prader Willi syndrome with growth failure . GH therapy is being increasingly used in children with idiopathic short stature with height below 1st percentile .  

11. MANAGEMENT  General measures include nutrition ( protein , Lysine, zinc , iron and calcium supplementation ) and physical activity.

12. Micronutrients Zinc the pituitary growth hormone (GH)–insulin-like growth factor-I (IGF-I) axis is responsive to zinc status. Both increased and decreased circulating concentrations of GH have been observed in zinc deficiency, although circulating IGF-I concentrations are consistently decreased. Other micronutrients like calcium, magnesium, and phosphorus are involved in bone and muscles health, which are central to growth.

13. B12  as an essential vitamin that positively regulates postweaning growth and bone formation through taurine synthesis and suggests potential therapies to increase bone mass.   Vitamin A Deficiency is associated with abnormal nocturnal GH secretion. Dietary supplementation of Vit. E and/or Se improve and upregulate the growth-related genes without effect on the general health status .