Why is bone health important in childhood?

Bones undergo changes throughout our lives, as old bone is broken down and new bone forms. But the most important time for building a strong skeleton is during childhood and adolescence. Bone strength depends on both the size of the bones and the amount of mineral they contain.

The greatest gains in bone size and mineral content occur in adolescence. At puberty, hormonal changes take place that start sexual maturity and speed up bone growth. Bones not only get longer and wider, they also get denser. People reach their peak bone mass, or maximum bone size and density, by their late teens or early twenties. As early as age 30, some bones begin to slowly lose mass.

The more bone mass we “Bank” in childhood and adolescence, the better we withstand the inevitable bone losses and the better protected we are from osteoporosis and bone fractures later in life.

What affects children’s bone health?

The genes we inherit, our hormones and our lifestyle all affect our peak bone mass. Genetic factors have the greatest influence on peak bone mass, but to reach his or her “genetic potential,” a child needs adequate levels of certain hormones along with healthy eating and exercise habits.

Growth hormone and the sex hormones estrogen and testosterone at puberty are essential for building bone mass in both boys and girls. Maintaining a healthy weight and getting enough vitamin D, calcium, protein, and physical activity are also key to bone health. Calcium is the main mineral in bone, and vitamin D helps the body absorb calcium. Weight-bearing exercise, such as running and jumping, helps build muscle and bone strength.

Adolescent girls need to be moderate in their approach to diet and exercise. Menstruation can stop in girls who exercise excessively or are extremely underweight (as in anorexia). Girls who never start their periods or stop menstruating often have low estrogen levels, which can harm their bone health.

Is your child getting enough vitamin D and calcium?

Vitamin D. Most of our vitamin D is produced when our skin is exposed to sunlight. Children get vitamin D from playing outdoors, but it’s hard to tell if they’re getting enough. Since few foods naturally contain vitamin D, most milk and infant formula are fortified (meaning vitamin D is added).

Infants, children, and adolescents need at least 400 IU (international units) of vitamin D each day. Children of all ages who do not get 400 IU a day from their diet should take a supplement, prescribed by their doctor.

Children and adolescents with dark skin, limited sun exposure, or certain chronic diseases are more likely to be deficient in vitamin D. A simple blood test can check for vitamin D deficiency.

Calcium. Pregnant and breastfeeding women need at least 1,000 mg of calcium each day, along with adequate vitamin D, to support their own and their babies’ bone health. The recommended daily calcium intake for children and adolescents varies by age:

0-6 months         210 milligrams (mg)

7- 12 months      270 mg

1-3 years            500 mg

4-8 years            800 mg

9-18 years          1,300 mg

What should you do with this information?

Set an example for your child by modeling good bone health habits. Keep calcium rich foods on hand and encourage physical activity. Talk about your child’s bone health whenever you consult your pediatrician. Ask if your child needs nutritional supplements or treatments for an underlying medical condition. If your child has a hormone related disorder that might threaten bone health, you should consult an Endocrinologist, a specialist in the field, about whether hormone treatment is needed.

]]> http://www.diabetesendocrinology.in/2010/02/19/bone-health/feed/ 0 http://www.diabetesendocrinology.in/2009/04/30/delayed-puberty-in-girls/ http://www.diabetesendocrinology.in/2009/04/30/delayed-puberty-in-girls/#comments Thu, 30 Apr 2009 09:16:21 +0000 admin http://www.diabetesendocrinology.in/?p=299 1. What is delayed puberty?

Failure to enter into puberty later than 14 years is called delayed puberty.

2. What are the causes of delayed puberty?

These can be divided into general causes and specific causes. Constitutional delay of growth and puberty, chronic childhood diseases and under nutrition are the general causes. The specific causes are related to under production of sex hormones.

3. What the problems related to sex hormone production?

The under production of sex hormones could be either because of problem in the pituitary gland or in the testes. If the problem lies in the pituitary gland then it is called hypogonadotrophic hypogonadism. If the problem is in the testes then it is called hypergonadotrophic hypogonadism.

4. What are the causes for the hypogonadotrophic hypogonadism?

They are:

1. Kallaman’s syndrome: Sense of smell is also affected
2. Tumors or radiation in the region of pituitary
3. Genetic problem

5. Why does hypergonadotrophic hypogonadism happen?

It is because of

1. Turner’s syndrome
2. Destruction of ovaries because of local radiotherapy, chemotherapy.

6. What are the features of delayed puberty?

The girls fail to develop breast enlargement, fail to experience pubertal growth spurt, menstrual periods.

7. What tests are done to know the cause?

The doctor orders for several hormones and scans. Some are done after giving stimulating hormones. LH and FSH, the two pituitary hormones responsible for stimulating testes to secrete the female sex hormones -estradiol and prgesterone, are measured at base line and post GnRH injection. Blood levels of estradiol are done. To detect the genetic defect karyotyping is done. This test tells about the genetic makeup of the individual. MRI scan of the brain and/or abdomen are also done.

8. How to treat these patients?

Improving the nutrition in under nourished children is very important in that group. But if the problem is because of sex hormone deficiency then oral estrogen in small doses is given. If break through bleeding occurs then progesterone is added.

Failure to enter into puberty later than 16 years is called delayed puberty.

2. What are the causes of delayed puberty?

These can be divided into general causes and specific causes. Constitutional delay of growth and puberty, chronic childhood diseases and under nutrition are the general causes. The specific causes are related to under production of sex hormones.

3. What the problems related to sex hormone production?

The under production of sex hormones could be either because of problem in the pituitary gland or in the testes. If the problem lies in the pituitary gland then it is called hypogonadotrophic hypogonadism. If the problem is in the testes then it is called hypergonadotrophic hypogonadism.

4. What are the causes for the hypogonadotrophic hypogonadism?

They are:

1. Kallaman’s syndrome: Sense of smell is also affected
2. Tumors or radiation in the region of pituitary
3. Genetic problem

5. Why does hypergonadotrophic hypogonadism happen?

It is because of

1. Klinefelter’s syndrome
2. Destruction of testes because of local radiotherapy, chemotherapy, testicular torsion, infection.

6. What are the features of delayed puberty?

The boys fail to develop facial hair i.e. beard and mustache, fail to experience pubertal growth spurt and their testes and penis also fail to enlarge.

7. What tests are done to know the cause?

The doctor orders for several hormones and scans. Some are done after giving stimulating hormones. LH and FSH, the two pituitary hormones responsible for stimulating testes to secrete the male sex hormone – Testosterone, are measured at base line and post GnRH injection. Blood levels of testosterone at base line and after hCG injection are done. To detect the genetic defect karyotyping is done. This test tells about the genetic makeup of the individual. MRI scan of the brain and/or abdomen are also done.

8. How to treat these patients?

Improving the nutrition in under nourished children is very important in that group. But if the problem is because of sex hormone deficiency then Inj. Testoviron can be given. To begin with the physician gives a small dose and then he increases it to reach 250mg every 4 weeks.

The problem of early blooming is called precocious puberty. If the girls show signs of puberty before the age of 8 years and if the boys before the age of 9 years then it is called precocious puberty.

2. What are the types of precocious puberty?

We divide this into four categories.

• Central (complete or true) isosexual precocious puberty
• Incomplete isosexual precocious puberty
• Sexual precocity due to gonadotropin or sex steroid exposure
• Variation in pubertal development

3. What could be the causes of the central precocious puberty?

Usually in girls the cause is unknown when it is called idiopathic. However it could be familial also. But in boys intracranial pathology like tumors, hydrocephalus, trauma, cranial irradiation are more common than idiopathic or familial cause.

4. What are the causes of incomplete isosexual precocious puberty in boys?

1. Gonadotropin secreting tumors
2. Autonomous androgen secretion

5. What are the causes of incomplete isosexual precocious puberty in girls?

• Follicular cysts
• Granulosa or theca cell tumors
• Adrenal rest tissue
• Estrogen administration from outside
• Hypothyroidism
• McCune – Albert syndrome

6. What are the variations in pubertal development?

They are of three different types. They actually do not denote precocious puberty and hence can be considered as normal variations only. They are premature thelarche (early breast enlargement without other signs), premature menarche (early periods without other signs) and premature adrenarche (early development of pubic and arm pit hair without other signs).

7. What are the implications of precocious puberty?

Precocious puberty is associated with both psychological and physiological implications. Psychologically the child is too young to adjust to the new situation. Physiologically it has a bearing on the ultimate height reached by the child. Although puberty is associated with initial growth spurt it ultimately causes early fusion of the bones thus reducing the final height.

8. How it is identified?

The doctor identifies the condition by the physical examination of the child where he notices the signs of puberty and then asks for the appropriate investigations.

9. What are those investigations?

He orders for the certain hormone tests by which one comes to know the blood levels of the hormones concerned with puberty are elevated or not. After that a stimulation test called GnRH stimulation test is performed. In this test the hypothalamic hormone GnRH is given and then the pituitary hormones are measured at 30 & 60 minutes. Seeing the pattern of these hormones one can diagnose precocious puberty. MRI scan of the brain and the adrenals are also requested in order to look at the structural lesions of these glands.

10. Is there any need to treat these patients?

Yes. This is because if this condition is left untreated then the final height of the child is compromised. Secondly there are psychological implications for the child as the child is not ready psychologically to accept the new situation.

11. What is the treatment for central precocious puberty?

Leuprorelin acetate 3.5mg given intra muscular every month suppresses pituitary FSH/LH secretion and hence stops the march of puberty.

12. How long these need to be given?

They need to be given at least until the normal age of puberty i.e. 10-12 years in girls and 12 years in boys.

13. Is there any problem in using this drug on long term basis?

No. Some may develop allergic reactions and some other may develop reduction in bone mineral density and hence increased dietary calcium supplementation may be necessary.

14. Will the puberty restart after stopping these drugs at the appropriate age?

Yes. It restarts once these drugs are stopped.

15. How to treat incomplete precocious puberty?

Treating the root cause like removal of the tumor causing the precocious puberty is the solution for this problem.

16. Do we have to treat premature thelarche, adrenacrche and menarche?

No, these treatments are not required as first two are self limiting conditions and the for the last none is required.

Puberty is the sequence of physical, sexual, physiological and psychological changes that take place at adolescence which brings one to adulthood. Most of the time it is the sexual maturity which takes the forefront but all the changes needs due attention because this is the time when one moves from parental control to personal control.

2. What happens when one enters puberty?

Puberty heralds sequential changes in the body. Different organs concerned with the sexual maturity develop at different times. In the girls the first sign is development of breast which is called as thelarchae in medical parlance. In the boys the testes enlarge first. From here onwards there is an orderly fashion of development in which the breast size progressively increases in girls while the testes and the penis increase in boys. This march is regulated by the interplay between the hormones produced by the thalamus, pituitary and ovaries/testes. They are called as GnRH, FSH & LH and estrogen/testosterone respectively. In both the sexes the hair in the armpit and around the pubis increases in thickness and darkens in colour. The doctors can determine the stage of puberty by noticing the growth of the breast or testes and amount of hair in the armpit and around the pubis. Another important change that is noticed is sudden increase in the height of both boys and girls. This is called pubertal growth spurt.

3. What is the normal age of entry into puberty?

While girls enter the puberty at an average age of 10-12 yrs the boys do so when they are around 12-14 years. Certain feature like genes, race, weight gain and overall nutrition determine the age of onset of puberty.

The completion of maturation process is rather wide, it may take 4 to 6 years.

Growth problems are very common but frequently missed. Schools, playgroups etc are unaware of the problems of dealing with very short child and your child may experience practical problems like unable to reach the peg or desk or sit on toilet. As they grow older they develop psychological problems of not being accepted by friends or treated as toy or picked up by other friends.

What is normal growth?

At birth child is around 50 cms. Growth is maximum in the first year of life, about 25 cm per year. It gradually declines from birth to about 4 years. During second year height gain is half of first year, around 12.5 cm and 6-7cm per year in third and fourth year of life. From fifth year till onset of puberty it is about 5 cm per year. During puberty girls gain 6-8 cm of height and boys grow about 7-10 cm.

How do I know if my child is growing okay?

Few clues for this are -

• If your child is not outgrowing his /her clothes and / or shoes
• If your child is among short ten children
• If your child looks younger than his classmates
• If your child has developed complex about height

What is a growth chart?

The best way of confirming normal / abnormal growth is by regular growth monitoring. This can be done by simple height measurement at regular interval of 3 months and plotting them on growth charts.

What are causes for short stature?

Most common cause for short stature is nutritional deficiency. Other causes are genetic or familial short stature, constitutional short stature or late bloomer, chronic diseases and hormonal deficiency. Among hormonal deficiencies they are thyroid and growth hormone (GH) deficiency. Rare causes are Turner syndrome, Intrauterine growth retardation and emotional deprivation.

What is Hypothyroidism?

Hypothyroidism means thyroid hormone deficiency. It can occur at any age from new born baby to old age. When a newborn baby develops hypothyroidism it is called congenital hypothyroidism. It is one of the preventable causes of mental retardation. Earlier the diagnosis and treatment better is the outcome. Earlier diagnosis has been achieved with the introduction of newborn screening for congenital hypothyroidism.

Symptoms of congenital hypothyroidism are prolonged jaundice, constipation, excessive sleep, poor feeding, large tongue hoarse voice, etc.

Symptoms in infancy and childhood are growth failure, constipation, dry skin, excessive sleep, etc.

What is IUGR ( Intrauterine growth retardation)?

Low birth weight or small for dates or babies weight is inappropriately low for duration of the pregnancy. This inappropriate low weight indicates that growth of the baby in womb has been unsatisfactory and this is why it is called intra uterine growth retardation or IUGR.

Is there treatment for short stature?

Yes, there is treatment for short stature. Initially good balanced diet with exercise, thyroid deficiency screening and treatment of chronic diseases are tried with regular growth monitoring. If all these factors are corrected and growth is not adequate then tests are done to rule out growth hormone deficiency. Growth hormone deficiency is treated with growth hormone.

What are the signs of GH deficiency?

Children with GH deficiency are short with normal body proportions and intelligence. Bone development may be delayed causing child to look younger than his actual age. There may be under development of mid facial structure and frontal bossing of the skull. They are often obese / overweight as GH controls fat deposition.

What is growth hormone deficiency?

Growth hormone is a hormone that regulates growth. GH deficiency occurs when pituitary gland (master gland, a small pea sized gland at the base of brain) fails to produce adequate amount of GH in the body.

How do you diagnose Growth hormone deficiency?

After all other possibilities of short stature have been ruled out, tests are done for growth hormone deficiency. First analyse growth rate in the growth chart, second, thorough physical examination, X-ray of hand and wrist to see bone development and compare it with height and chronological age. Confirmation is by giving the child a substance that releases growth hormone burst in normal children. If the release is sub optimal it confirms growth hormone deficiency.

Are there any side effects with the treatment?

No, there are no side effects with this, as it is developed by recombinant DNA technology but correct dose needs to be used.

What is the set back with Growth hormone?

COST. It is an expensive medicine. Hence it is not reachable by everybody. It needs to be given for a minimum period of one year and the cost increases if the child is older and heavier.

Why an adult cannot grow taller?

Adults cannot grow as their bones are fused. Once puberty is reached the sex hormones, oestrogens in girls and testosterone in boys cause fusion of bones. Once bones are fused we cannot grow any more.