{"id":319,"date":"2019-04-02T06:16:16","date_gmt":"2019-04-02T06:16:16","guid":{"rendered":"http:\/\/antp16.epgpbooks.inflibnet.ac.in\/?post_type=chapter&p=319"},"modified":"2019-04-02T06:32:03","modified_gmt":"2019-04-02T06:32:03","slug":"methods-of-assessing-abnormal-growth","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/antp16\/chapter\/methods-of-assessing-abnormal-growth\/","title":{"rendered":"Methods of assessing abnormal growth"},"content":{"raw":"
\"epgp<\/a>\r\n<\/span><\/div>\r\n \r\n\r\n \r\n
\r\n\r\n \r\n\r\nContents:<\/strong>\r\n\r\n \r\n\r\nIntroduction\r\n\r\nShort stature\r\n\r\nGrowth velocity\r\n\r\nCauses of short stature\r\n\r\nNutrition and systemic diseases\r\n\r\nBone disorders\r\n\r\nIntrauterine growth retardation\r\n\r\nGrowth and puberty\r\n\r\nBone age\r\n\r\nObesity\r\n\r\nSummary\r\n\r\n \r\n\r\nLearning Objectives:<\/strong>\r\n\r\n \r\n\r\nTo understand:\r\n\r\n1.\u00a0\u00a0\u00a0\u00a0\u00a0 What is growth?\r\n\r\n2.\u00a0\u00a0\u00a0\u00a0\u00a0 What is abnormal growth?\r\n\r\n3.\u00a0\u00a0\u00a0\u00a0\u00a0 What causes short stature?\r\n\r\n4.\u00a0\u00a0\u00a0\u00a0\u00a0 About Growth velocity, metabolic disorders, hormonal disorders\r\n\r\n \r\n\r\nIntroduction<\/strong>\r\n\r\n \r\n

Growth is the progressive increase in the size of a person or parts of a person. Development is the acquisition of various skills to perform specific functions. Growth and development go together but at different rates. The healthy state of a person can be assessed by his growth and development. Measurement of growth therefore is very essential to know whether the growth is normal or abnormal. Failure to grow normally indicates symptom of disease.<\/span><\/p>\r\n \r\n

Growth takes place when bones of the arms, legs, and back increase in size. This usually occurs before the ages 16 to 18 years. The bone age or the maturation of the bone can be assessed by taking the X-ray of the hand or knee. There are many causes of abnormal growth ,some are temporary and merely variations of the normal pattern of growth. Abnormal growth may result due genetic factors or may be associated with other physical problems. The proper health and growth of a child can only be maintained by regularly getting the child examined and measured.<\/span><\/p>\r\n \r\n

There are a number of conditions that may lead to decreased or increased growth rate and \/ or short or tall stature, which could be detected through growth monitoring. Conditions in which stature outside the normal range is often the only or most significant presenting feature are growth harmone deficiency and Turner\u2019s syndrome (TS) .Such conditions justify growth screening in childhood.<\/span><\/p>\r\n \r\n

1.\u00a0<\/strong>Short stature <\/strong>may result from hypothyroidism, psychosocial deprivation, and intrauterine growth retardation or other chronic diseases. Tall stature may be due to Marfan syndrome and Klinefelter syndrome, or a sign of treatable endocrine disorders. Early detection of organic causes of abnormal growth is important. When a child is born the size is almost same in everyone but postnatally every individual varies in size and shape. Established growth standards i.e. established range of normal height and weights for different age groups can be used to monitor growth of children.<\/span><\/p>\r\n \r\n

A growth chart is used to compare a child\u2019s height and growth rate with those of others of the same age. A standard growth chart is the one in which the researchers take a large number of children of different ages and make a graph of their heights and weights. The most commonly used growth charts are from the National Center for Health Statistics (NCHS) and are age and gender specific. The height at the 50th percentile means the height at which half of the children of that age are taller and half are\u00a0<\/span>shorter. The 25th percentile means 75 percent of the children are taller at that age, and 25 percent are shorter. The 75th percentile means that 75 percent will be shorter and 25 percent taller.<\/span><\/p>\r\n \r\n

As there is a lot of variation, and if children are between the 3rd and 97th percentile but if they are growing at a normal rate, they will be regarded as normal. The reasons for such differences are searched for. These children simply may have inherited \u201cshort\u201d or \u201ctall\u201d genes from their parents.In most of the cases, they will however continue to grow at a normal pace. What is the normal growth rate during childhood? Most children establish a pattern of growth by 3 years of age and do not deviate from this pattern until the onset of puberty. During this time, the normal growth rate is 2-2.5 inches\/year (5-6.5 cm\/year). When children in this age group cross over or change growth channels, this may signal a growth problem and should be evaluated further.<\/span><\/p>\r\n \r\n

1.1. Mid-parental Height<\/strong>: This calculation provides a target mean and range for the genetic potential of a child based upon the biologic parents' heights. This calculation alone is not sufficient to predict final height; it only calculates a reference range for assessing growth .mid-parental height = (father's height - 5 in.) + (mother's height) for girls (inches) 2 mid-parental height = (mother's height + 5 in.) + (father's height) for boys (inches) 2 Target height = mid-parental height \u00b1 2 SD (1 SD = 2 in).<\/span><\/p>\r\n \r\n

Single Height measurement identifies children, whose height is outside the normal range. In contrast, repeated height measurements over time allow for calculation of a growth rate (or growth velocity) and can be used to define abnormal growth in terms of a crossing of the height centiles, thereby identifying abnormality through the pattern of growth within the individual (Rogol et a.2000).<\/span><\/p>\r\n \r\n

1.2. Growth velocity <\/strong>provides a superior measure because changes in actual height only become evident after altered growth rates have been sustained for a period of time. A normal child tends to follow a given centile line or pattern, deviations in growth away from the percentile are difficult to detect over short intervals using the growth curve. This is one of the most important reasons for calculating the growth rate or growth velocity(Brooke et al.,1986). Evaluating the growth velocity at each routine and acute illness visit provides the earliest identification of problems with growth.<\/span><\/p>\r\n \r\n

Growth velocity is normal if growth is maintained along an isobar line. When growth slows and crosses the height centiles, even if still within the normal range on the growth chart, a pathological aetiology is more likely. Growth deceleration is defined as a growth velocity that is below the 5th\u00a0<\/span>percentile for age and gender (e.g. <5 cm\/year after the age of 5 years) or a height drop across two or more percentiles on the growth chart. When growth velocity is abnormally decreased, height measurements will progressively fall across isobars, sometimes termed \u2018falling off the curve\u2019. Conversely, acceleration of growth velocity results in crossing the upper isobars but not all growth acceleration is beneficial, exposure to abnormal sex steroid whether from an exogenous or endogenous source can lead to early accelerated growth, premature fusion of the epiphyses and ultimately, short adult stature.<\/span><\/p>\r\n \r\n

Growth velocity must therefore be interpreted in conjunction with attained height because position on the growth curve is essential for interpreting the growth rate and determining the effectiveness of interventions. Short stature with decreased weight-for-height ratio may indicate the presence of a chronic systemic disease. Indeed, almost all systemic diseases may attenuate growth to a degree that is dependent on the severity and treatment of the underlying disease. In some cases (e.g. irritable bowel syndrome, coeliac disease, chronic renal insufficiency), growth may be impaired for several years before the gastrointestinal or renal symptoms are evident.<\/span><\/p>\r\n \r\n

In contrast to these more subtle diseases, growth failure associated with other chronic disease (e.g. heart, immunological, etc.) is clinically evident and obviously related to the underlying condition. Children who are undernourished or suffer malnutrition also present with similar symptoms; short stature and reduced weight for height. In children with a nutritional deficiency despite access to food (e.g. anorexia nervosa or poorly controlled type 1 diabetes), weight loss is more pronounced than the decline in linear growth, and there may also be delayed sexual maturity and bone age.<\/span><\/p>\r\n \r\n

Genetic or syndromic causes of short stature are often diagnosed because of abnormalities found during clinical examinations.<\/span><\/p>\r\n \r\n

The intrinsic biological complexity of the dynamics of human growth, however, makes the use and interpretation of measurements of growth challenging. Growth velocities of individual children are characterized by very high variability in consecutive growth intervals. Intermittent short growth arrests and growth spurts are frequent in child development. It is not unusual for a child to grow at the 95th velocity centile during one month and at the 20th velocity centile in the following month. Correlations between subsequent different patterns of growth are generally low; this reflects both a natural pattern\u00a0<\/span>of saltatory growth and possible catch-up or catch-down growth that contributes to overall narrowly canalized patterns in the attained growth trajectories of individual children.<\/span><\/p>\r\n \r\n

Growth velocity is best assessed using measurements taken at 3- to 4-monthly intervals in infants and at 6-monthly intervals in older children. As young children often have growth spurts, the most accurate estimates of yearly growth velocity are derived from averaging 12-monthly height (or length) measurements as compared with averaging measurements from intervals of < 12 months. Although the latter approach may intuitively appear more useful, imprecision in height measurements means that, in the short term, height velocity may not adequately identify reduced growth during routine growth monitoring (Voss et al.1991).<\/span><\/p>\r\n \r\n

Although obtaining and plotting height measurements does not require expensive or sophisticated equipment, training and attention to detail are warranted(Cole, 2002). Indeed, two of the most common reasons for the misdiagnosis of growth disorders and inappropriate referrals for further evaluation are errors in height measurement or inaccurate plotting of values on a growth curve(Voss,1994).<\/span><\/p>\r\n \r\n

An appropriate growth chart is an essential tool for the screening, surveillance and monitoring of children's growth.<\/span><\/p>\r\n \r\n

The growth of preterm children differs from that of children born at full term and is dependent on their gestational age. Evidence suggests that boys, in particular, may be vulnerable to the complications of preterm birth that influence growth (Bocca-Tjeertes et al., 2012).When assessing height on a growth chart it is therefore important to correct for premature birth and to use their corrected age, rather than their actual age since birth. For example, a child born at 31 weeks\u2019 gestation was born nine weeks early (40\u201331 = 9 weeks). The corrected age for this child will always be nine weeks less than his or her actual age since birth. The large number of clinical conditions associated with short stature can make the task of identifying the cause of short stature challenging.<\/span><\/p>\r\n \r\n

The European Society of Paediatric Endocrinology (ESPE) classified the main causes of short stature into three groups:<\/span><\/p>\r\n

(i)\u00a0 \u00a0 primary growth disorders,where the condition is intrinsic to the growth plate;<\/span><\/p>\r\n

(ii)\u00a0 secondary growth disorders, where the milieu of the growth\u00a0<\/span>plates change as a consequence of the condition; and<\/span><\/p>\r\n

(iii)\u00a0 when there is no identifiable cause of short stature (idiopathic short stature [ISS] or growth failure of unknown aetiology) ( Wit et al.2007).<\/span><\/p>\r\n \r\n

1.3 Causes of short stature<\/em><\/strong><\/p>\r\n \r\n

1. Primary growth failure<\/span><\/p>\r\n \r\n

Clinically defined syndromes including Down syndrome, Turner syndrome, Noonan syndrome, Prader\u2013Willi syndrome and Silver\u2013Russell syndrome, Small for gestational age (SGA) ,with failure of catch-up growth, Congenital bone dysplasia, for example, achondroplasia, Hypochondroplasia<\/span><\/p>\r\n \r\n

2.\u00a0 Secondary growth disorders <\/span><\/p>\r\n \r\n

Endocrine causes<\/span><\/p>\r\n

Growth hormone deficiency (GHD) either congenital or acquired (hypothalamic-pituitary region lesions such as craniopharyngioma or head trauma)<\/span><\/p>\r\n

Multiple pituitary deficiencies <\/span><\/p>\r\n

Cushing syndrome <\/span><\/p>\r\n

Hypothyroidism<\/span><\/p>\r\n

Consequences of precocious puberty <\/span><\/p>\r\n

Other disorders of the GH\u2013IGF-I axis <\/span><\/p>\r\n

IGF-I deficiency <\/span><\/p>\r\n

ALS-deficiency<\/span><\/p>\r\n

IGF-I resistance<\/span><\/p>\r\n \r\n

Metabolic disorders<\/strong><\/p>\r\n \r\n

Poorly controlled diabetes mellitus<\/span><\/p>\r\n

Disorders of lipid, carbohydrate, protein metabolism, for example, chronic renal insufficiency Disorders in organ systems and systemic disorders, for example, cardiac, pulmonary (cystic fibrosis), liver, intestinal (short bowel syndrome and coeliac disease), renal, chronic anaemia, juvenile arthritis\u00a0<\/span>Psychosocial conditions such as emotional deprivation, anorexia nervosa Systemic or local glucocorticoid therapy. Treatment of childhood malignancy, for example, chemotherapy, total body irradiation.<\/span><\/p>\r\n \r\n

2.1<\/strong>\u00a0\u00a0<\/span>NUTRITION AND SYSTEMIC DISEASES<\/strong><\/p>\r\n \r\n

There are many diseases and disorders that can cause short stature and growth failure. Malnutrition in some parts of the world leads to abnormal growth. There are a number of intestinal disorders which may lead to poor absorption of food. Failure to absorb nutrients and energy from food then leads to growth failure. Children with these conditions may have complaints that involve the stomach or intestines. Treatment of these conditions often involves a special diet. Normal growth usually resumes after proper treatment is taken. Chronic diseases that may impair growth include diabetes, congenital heart disorders, sickle cell disease.<\/span><\/p>\r\n \r\n

2.2<\/strong>\u00a0<\/span>BONE DISORDERS<\/strong><\/p>\r\n \r\n

Several inherited bone diseases influence growth and maturation. In achondroplasia, a dominant inherited abnormality, the cartilage cells mature less rapidly than normal. This leads to short long bones and the skin of limbs tends to hang in folds. Physical performance is not much affected. A recessive abnormality known as Osteochondrodystrophy, results in decreased growth of articular cartilage and consequently metaphysical development is delayed. Degenerative changes in joints, sclerosis may lead to restriction of movement. The underlying causes of most of these skeletel dysplasias are not known. Researches are being done to identify the genetic and biochemical mechanisms.<\/span><\/p>\r\n \r\n

2.3<\/strong>\u00a0<\/span>INTRAUTERINE GROWTH RETARDATION<\/strong><\/p>\r\n \r\n

Some infants are small at birth, as they are born earlier than usual time. Such babies are premature. Some infants are shorter and weigh less than they should at birth. In other words, they had a chance to grow in the womb, but did not reach the length and weight they should have for their gestational age\u00a0<\/span>(length of the time in the womb). This failure to grow normally in the womb is called intrauterine growth retardation.<\/span><\/p>\r\n \r\n

A problem with the placenta, the organ in the mother\u2019s womb that supplies nutrients and oxygen to the baby may result in such conditions. During pregnancy, German measles a viral infection may affect the placenta , causing intrauterine growth retardation. <\/span>This condition cannot be identified in some case<\/strong>. Such children will remain small throughout life, whereas some of them may reach normal size. Intrauterine growth retardation may result because of so many reasons. Researches are being done to see if growth hormone is effective in increasing the growth rate and adult height of these children.<\/span><\/p>\r\n \r\n

2.4<\/strong>\u00a0<\/span>GROWTH AND PUBERTY<\/strong><\/p>\r\n \r\n

At the time of adolescence, a growth spurt normally occurs. Girls experience growth spurt about two years earlier than boys. Rates of growth and changes during puberty vary from person to person. Parent\u2019s growth and puberty patterns often are passed on through their genes to their children. If one or both parents had a late puberty, then their children are more likely to reach puberty later and to experience a later growth spurt. This is also known as constitutional growth delay.<\/span><\/p>\r\n \r\n

2.4.1. SEX HORMONES<\/strong><\/p>\r\n \r\n

The increase in growth rate during puberty is marked by the increase in production of sex hormones which is estrogen from ovaries in girls, and testosterone from the testicles in boys. These hormones are responsible for skeleton growth and maturation. Hormones produced by the adrenal glands at puberty contribute to the development of secondary hair and under arm hair. They have little effect on bone growth. Disorders of pubertal development can affect a child\u2019s growth pattern and ultimate height. Disorders during puberty are usually grouped into two categories. (i) Precocious or premature puberty. (ii) delayed or late puberty.<\/span><\/p>\r\n \r\n

2.4.2<\/strong>\u00a0<\/span>PRECOCIOUS PUBERTY<\/strong><\/p>\r\n \r\n

Puberty is considered precocious (early) if changes in sexual development manifest before age eight for girls and before age ten for boys. Most symptoms of precocious puberty are similar to normal\u00a0<\/span>puberty. The early risk in sex hormone levels in children with precocious puberty experience early growth spurts. Although initially this causes these children to grow taller than others of their age, their skeletons mature more rapidly, which results in stopping the growth at an early age. Therefore precocious puberty if left untreated may lead to a decrease in a child\u2019s ultimate height.<\/span><\/p>\r\n \r\n

There are many possible causes for precocious puberty, including brain tumors or genetic abnormality and other disorders of the central nervous system; and tumors or other conditions that cause the gonads or adrenal glands to overproduce sex hormones. In girls, however, the majority of cases of precocious puberty are idiopathic, which means a cause cannot be identical. Precocious puberty can be divided into two categories central precocious puberty and peripheral precocious puberty.<\/span><\/p>\r\n \r\n

Central Precocious Puberty also known as gonadotropin-dependent precocious puberty, occurs when the abnormality is located in the brain. Central precocious puberty is the most common form of precocious puberty and affects many more girls than boys. The causes of central precocious puberty include: brain tumors, or infection<\/span>.<\/strong><\/p>\r\n \r\n

2.4.2 DELAYED PUBERTY<\/strong><\/p>\r\n \r\n

Delayed puberty occurs when the hormonal changes of puberty occur later than occurring at normal range of ages. Puberty is considered late if it has not begun by age 13 in girls or by age 15 in boys. Most children who experience delayed puberty are following the normal pattern called constitutional growth delay.<\/span><\/p>\r\n \r\n

Several disorders, such as disorders of the hypothalamus, pituitary, ovaries, and testicles can result in delayed puberty by interfering with the rise in sex hormones during puberty. Many chronic disorders of other body organs and systems (such as the intestines and lungs), as well as long-term medical treatments also may cause delayed puberty. Children with delayed puberty go through an otherwise normal puberty, just at a late age. This delay is due to the fact that the is maturing slowly than average, also known as constitutional delay of puberty. This condition often runs in families.<\/span><\/p>\r\n \r\n

Improper nutrition due to long-term illnesses can delaying puberty strenuous physical training (running or gymnastics) may cause delayed puberty in girls. A medical condition, in which the sex glands (the testes in men and the ovaries in women) produce few or no hormones may cause delayed puberty.\u00a0<\/span>Hypogonadism can be divided into two categories: secondary hypogonadism and primary hypogonadism.<\/span><\/p>\r\n \r\n

The pattern of skeletal maturity is also helpful in differentiating the type of short stature.<\/span><\/p>\r\n \r\n

3.\u00a0 <\/strong>BONE AGE <\/strong>- skeletal maturity is observed directly by visualization of epiphyseal growth plates on X-ray. X-rays are useful to determine skeletal age \u2013<\/span><\/p>\r\n

1.\u00a0\u00a0\u00a0\u00a0\u00a0 <1 year: shoulder x-ray.<\/span><\/p>\r\n

2.\u00a0 \u00a0 \u00a01-13 years: hands and wrists<\/span><\/p>\r\n

3.\u00a0 \u00a0 \u00a0>13 years: elbow and hip<\/span><\/p>\r\n \r\n

Bone age is necessary for interpreting hormone levels in pubertal age; for diagnosis of precocious puberty or hyperandrogenism; for deciding whether to treat or not the above mentioned conditions; for predicting adult height in normal children; in evaluating any child with growth and\/or puberty disorders; in deciding the time to start replacement therapy in hypogonadism; in monitoring children on growth hormone therapy.<\/span><\/p>\r\n \r\n

4.\u00a0<\/strong>GENETIC DISORDERS<\/strong><\/p>\r\n \r\n

4.1.\u00a0<\/strong>TURNER SYNDROME<\/strong><\/p>\r\n \r\n

Short stature in girls may be caused by a genetic condition that affects the X chromosome. Chromosomes are small thread-like bodies in the nucleus of each cell; they contain the genetic material that determines the characteristics we inherit. Two of these chromosomes determine sexual development-the X and Y chromosomes. Boys have one X and one Y chromosome, and girls have two X chromosomes. In girls with Turner Syndrome, one of the X chromosomes is misshapen or missing in many or all body cells. Because of this, affected girls are short and may have undeveloped ovaries. Intelligence is normal. Turner Syndrome may be present because of the presence of certain physical features, but poor growth is sometimes the only sign. A special blood test (karypotype) is done to look for damaged or missing sex chromosomes. Replacement of the missing ovarian hormones in these girls help to develop normal female sexual characteristics.<\/span><\/p>\r\n \r\n

4.2.<\/strong>\u00a0<\/span>MARFAN SYNDROME<\/strong><\/p>\r\n \r\n

Some genetic conditions cause abnormal tall stature. Marfan syndrome is a hereditary condition affecting connective tissue and is associated with tall stature. People with Marfan syndrome have very long arms and legs, eye problems, and differences in facial features. Other physical problems, such as heart abnormalities, also may be present. It is commonly believed that Abraham Lincoln had Marfan syndrome. Klinefelter\u2019s syndrome is also one such example of abnormal tall stature.<\/span><\/p>\r\n \r\n

4.3.<\/strong>\u00a0<\/span>HORMONES AND GROWTH DISORDERS<\/strong><\/p>\r\n \r\n

Growth is controlled by hormones (chemical messengers) from various glands. One of the most important, growth hormone is secreted by the pituitary gland. The gland looks like a peanut sitting at the base of the brain. Other hormones also are essential for growth. The thyroid gland in the neck secretes thyroxine, a hormone required for normal bone growth. Sex hormones are secreted from the ovaries.<\/span><\/p>\r\n \r\n

4.4.<\/strong>\u00a0<\/span>PITUITARY HORMONES<\/strong><\/p>\r\n \r\n

The pituitary gland is attached by a stalk to the hypothalamus, an area of the brain that controls the function of the pituitary. The anterior or front part of the pituitary gland secretes the following hormones that can affect growth:-<\/span><\/p>\r\n\r\n