A site for medical students - Practical,Theory,Osce Notes

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Showing posts with label built. Show all posts

What is cretinism ?

Cretinism is a condition produced due to hypothyroidism since birth due to partial or complete failure of thyroid gland  (commonly it is due to thyroidal agensis).
Juvenile myxoedema is a condition with onset of hypothyroidism since childhood but develops before puberty ,this is only due to dyshormonogenesis
Myxoedema is characteried by onset of hypothyroidism after puberty (probably Hashimolo's thyroiditis is the commonest cause of myxoedema).
What are the morphologic characteristics of cretin?
 The facies in cretinism 
  • Appearance is dull and idiotic.
  • There is depressed bridge of the nose, broad flat nose with big nostrils.
  • Hypertelorism (widely set eyes) with wrinkling of eyebrows : narrow palpebral fissures.
  • Cretin has Sparse hair with dry skin.
  • Their lips are thick and everted with big, protruded tongue (macroglossia)
  • There is Delayed dentition.
The other features are
  • Short stature but they maintains the infantile proportion, ie. upper segment > lower segment.
  • These patients are lethargic and apathetic.
  • Memory is grossly impaired. Markedly retarded intelligence
  • Skin is dry. rough  and cold with sparse scalp hair.
  • Thick and short neck with presence of supraclavicular pad ot fat.
  • Pot-bellied abdomen with umbilical hernia is observed
Clinical features of hypothyroidism in neonatal period
Hypothyroididm in the neonatal period may be associated with the following
  • Prolonged physiological jaundice.
  • Somnolence.
  • Feeding problem (difficulty in sucking)
  • Constipation
  • Hoarse cry 
  • Delayed milestones of development (is observed in  later months)
How will you diagnose cretinism based on laboratory tests?
Blood investigations
  • High serum cholesterol.
  • Low protein bound iodine
  • Low radioactive I131 uptake.
  • T3 and T4 levels are low with high TSH level.
ECG - Low voltage complex is seen.
Skeletal x-ray (of long bones and pelvis) 
In cretinism there is delayed closure of epiphysis (i.e. bone age is less than that of chronological age).
Epiphyseal dysgenesis - Instead of one epiphysis, there are multiple epiphysis (This is DIAGNOSTIC of cretinism).
How will you treat Cretin?
  • Very small dosage of L-thyroxine is needed. Initial dose is 10 to 25 microgram and the dose is adjusted according to clinical improvement as well as the biochemical findings.
  • Rehabilitation.

What are the cardinal features of achondroplasia ?

Dwarfism in achondroplasia is due to decrease in the proliferation of cartilage present in growth
plate.This  is an autosomal dominant disease and is usually recognised at birth. The dwarf jokers we see in the circus are usually achondroplasia patients. 
The characteristics features are 
  • Dwarfism.
  • Normal mental and sexual development.
  • Short limbs.
  • Large head with saddle nose.
  • Lumbar lordosis: kyphoscoliosis.

What is pseudohypoparathyroidism ?

Pseudohypoparathyroidism  is a condition with increased  secretion of parathormone (PTH) is there but due to end organ resistance, there is no response to PTH hormone resulting in clinical features of hypoparathyroidism. This is a hereditary disorder with distinctive skeletal and developmental defects. These patients have elevated levels of serum PTH.
The common features are :
  • Short height with stocky built.
  • Round face with short neck.
  • Mental retardation.
  • Epileptic convulsions.
  • Short 4th and 5th metacarpals and metatarsals.
  • Basal ganglia calcification.

How will you differentiate dwarfism by body ratio?

Based on upper and lower segment ratio dwarfism is classified as follows
Upper segment = Lower segment is seen in 
  • Hereditary.
  • Constitutional
  • Pituitary dwarf.
Upper segment > Lower segment is seen in 
  • Achondroplasia.
  • Cretinism
  • Juvenile myxoedema.
Upper segment < Lower segment is seen in 
  • Spinal deformities
You should always remember that short stature may be associated with features of delayed puberty.

Dwarfism and its causes

Dwarfism is defined as marked permanent shortness of stature, with predicted adult height of the person less than 4 standard deviations from the mean. An adult may be called a dwarf, if his height is less than 4 feet.
What are the causes of short stature?
Normal variant of short stature
  • Familial short stature
  • Constitutional growth delay
  • Racial.
Pathological causes of short stature
Proportionate dwarfism
  • Prenatal
  • Intrauterine growth retardation 
  • Antenatal infection in mother (TORCH*,syphilis, AIDS)
  • Antenatal consumption of alcohol, tobacco, heroin
  • Chromosomal disorders (Down's syndrome, Turner's syndrome). 
  • Postnatal
  • Malnutrition ,Protein-energy malnutrition, anorexia nervosa
  • Endocrine disorder growth hormone deficiency, hypothyroidism, congenital adrenal hyperplasia, precocious puberty pseudohypoparathyroidism
  • Cardiovascular disorders of cyanotic and acyanotic congenital heart disease, early onset rheumatic heart disease.
  • Respiratory disorders Kartagener's syndrome, cystic lung disease, childhood asthma 
  • Renal disorders renal tubular acidosis, renal rickets, nephrotic syndrome, chronic' pyelonephritis
  • Blood disorders ,chronic anemia like thalassemia or sickle cell anemia leukemia
  • Psychosocial disorders (maternal deprivation)
Disproportionate dwarfism
  • Rickets 
  • Skeletal dysplasia (kyphosis, lordosis, scoliosis)
  • Defective bone formation (osteopetrosis, osteogenesis imperfecta)
  • Defective cartilage growth (achondroplasia multiple cartilagenous exostosis)
  • Defective bone matrix (fibrous dysplasia)
  • Inborn error of metabolism (mucopolysaccharidosis)
  • Calcium and phosphorus metabolism defects (hyperphosphatemic rickets)
  • Metabolic disease (Wilson's disease, zinc deficiency).
What are the common causes of shortstature?
  • Hereditory
  • Constitutiona; delay in growth
  • Protein energy malnutrition (this is the commonest cause of malnutrition in developing countries)
  • Rickets.
  • Cretinism.
  • Pituitary dwarf.
  • Achondroplasia: mucopolysaccharidosis
  • Congenital cyanotic heart diseases e.g. Fallot s tetralogy
  • Gross kyphoscoliosis
  • Down’s syndrome or Turner's syndrome.

What are the clinical features of marfan's syndrome ?

Marfan syndrome is basically due the defect in collagen cross-linking  that may be responsible for abnormalities in supporting tissue. It is an autosomal dominant disease.

It is a syndrome comprising a tetrad of features
  1. Familial (autosomal dominant)
  2. Lens dislocation (upward)
  3. Great vessel (aortic or pulmonary) dilatation and  dissection
  4. Long tubular bones.
The arm span is 7.5 cm > height
Lower segment  5cm more than the upper segment

The abnormalities in marfans syndrome are the following
1. Skeletal abnormalities
  • Tall and thin (asthenic individual)
  • Crown to heel height is above average (ie. tall stature).
  • Upper segment : Lower segment = < 0.9
  • Arm-span > height
  • The arm span is more than the height of the patient by at least 5 cm.
b. Skull—Dolicocephalus  is long and narrow facies
c. High arched palate
d.Chest and spine—Pectus carinatum, pectus excavatum, straight back syndrome, kyphosis, scoliosis
e. Limbs—Long thin limbs and long thin fingers(Arachnodactyly)
Metacarpal index more than 8.4 this is calculated by taking the length of 4 metacarpals divided by its width at its midpoint then values are averaged
f. Joint hypermobility and ligament laxity
Hyperextensible joints (Steinberg’s sign or thumb sign - in which the thumb when opposed across the palm extends beyond the outer border of the palm).
Wrist sign
To elicit it the patients  is asked  to enclose his wrist with his thumb and little finger of hand then these digits will overlap
g. Feet—Pes planus, pes cavus, hallux valgus.
B.Subluxation or dislocation of lens upwards and outwards (look for irldodoncsls).

Other Ocular Defects are the following
  • Microcornea
  • Cataract
  • Strabismus
  • Myopia
  • Retinal detachment
  • Iridodonesis.
  • Cardiovascular abnormality
  • Cardiac Defects
  • Aneurysm of aorta
  • Dissection of aorta
  • Sinus of Valsalva aneurysm
  • Aortic regurgitation
  • Mitral or tricuspid valve prolapse syndrome
  • Atrial septal defect (ostium secundum)
  • Ventricular septal defect
  • Dilatation of the pulmonary artery..
Mental retardation is not seen In Marfans syndrome

What is Tall stature ?

Tall stature is defined as the height of the person more than  97th percentile of normal population of same age and sex.
Common causes for tall stature are the following
  • Constitutional
  • Racial 
  • Marfan's syndrome
  • Gigantism and acromegaly
  • Disorder of amino acid metabolism
  • Supermales (XYY) and superfemales (XXX).
How to differentiate tall stature by body ratio ?
Upper segment to lower segment ratio of our body is approximately
1.7:1 at birth 
By the age of 10 years the ratio becomes I : I 
it is approximately 0 .8: 1 in adulis
This is beause the legs grow more rapidly than the trunk 
Tall stature is classified as proportionate and disproportionate according to the uppersegment and lower segment ratio
1.Upper segment = Lower segment is seen in proportionate tall stature:
  • Constitutional, and
  • Pituitary causes.
2.Lower segment > Upper segment is seen in disproportionate tall stature
  • Marfan's syndrome.
  • Klinefelter’s syndrome,
  • Hypogonadism
  • Homocyslinuria.
3.Upper segment > Lower segment is found in 
  • Precocious puberty.
  • Adrenal cortical tumour.
What are the clinical associations in tall stature?
Accident proneness, isolated signs of virilism' s, signs of early puberty and rarely symptoms of hvperthyroidism
You should always examine the testis, palate (high-arched), spine and CVS (for Aortic regurgitation) in tall stature

What is Gigantism ?

Gigantism is said to be present in an individual, when his or her  height exceeds six feet, six inches.
Types of Gigantism
1. Hereditary: Primary or genetic.In this type the body is perfectly proportioned. They are normal mentally, physically and sexually.
2. Endocrine gigantism: The following types are seen.
a. Hyperpituitary gigantism: They are well-proportioned and have good physical and sexual development.
b. Eunuchoid gigantism: They are tall and long limbed individuals with infantile sex organs, e.g.Klinefelter's syndrome.

Cardinal features of Homocystinuria

Basic abnormality is reduced activity of enzyme cystathionine betasynthatase
Autosomal recessive inheritance is seen 
Mental retardation is present
There is upward lenticular dislocation
Thrombotic episode can occur
Patients are tall statured

What are the diagnostic points in klinefelter's syndrome?

Following are the diagnostic clue to klinefelters syndrome
1.Tall stature (due to hypogonadism).
2.Lower segment > upper segment of the body. Crown to pubis length < pubis lo heel
3. Gynaecomastia with loss of secondary sexual characters         
4.Phenotypically male with small, firm testis.
5.Mental subnormality.
6.Azoospermia (sterility) wilh elevated levels of plasma and urinary gonadotropinins
7.Chromatin barr body is present in buccal smear. Chromosal pattern is 47XXY in klinefelters syndrome

Anthrapometry -How to examine the stature of the patient ?

Anthropometry is the measurements of height (stature), weight, arm span, upper segment-lower segment ratio.
Following are the Anthropometry types 
Endomorphy - Soft rounded body where the digestive viscera dominate.
Mesomorphy - Muscles, bones and connective tissue derived from the embryonic mesoderm dominate.
Ectomorphy - Fragile, thin built with linearity or angularity is called ectomorphy.This is characterised by long narrow hands, long feet, shallow thorax, small waist and tall stature
What is stature?
Stature is defined as total height measured from vertex of head to the soles of the feet. It is a sum total of upper segment measurement (measured from vertex of head to the upper border of symphysis pubis) + lower segment measurement (measured from top of symphysis pubis to soles of the feet).
The relationship between upper segment measurement (from vertex to symphysis pubis) and lower segment measurement (from symphysis pubis to the heel) also varies with age as follows:
What is the Normal US: LS ratio 
Normal US: LS ratio is 1:1
Age - Uppersegment/lower segment
a. At birth=1.7:1
b. 3 years =1.4:1
c. 10 years=1:1
d. Adult  = 0.8:1
Infantile body proportions: US > LS height > arm span.
How to measure Arm span?
It is the distance between the tips of the middle fingers of the two hands, with both the arms held outstretched horizontally outwards from the body
According to the age the relationship between arm span and stature (height) varies as follows
Age-Arm span minus height (in cm)
0-7 years= -3
8-12 years=0
More than 12 years=+1 in females and +4 in males
What is build' or built' ?
It is the skeletal framework’ of a person in relation to his/her age and sex compared to a normal person
Build is classified into two groups:
I) Short stature
2) Tall stature (less common than short stature).
Dwarfism is a condition where the height of the patient is below 3rd percentile of normal population of same age and sex.
Tall stature height of the person is above 97th percentile of normal population of same age and sex.
Stature > Arm Span is seen in 
1. Adrenal cortex tumour
2. Precocious puberty.
This is because of early epiphyseal fusion.
Arm Span > Stature is seen in 
1. Eunuchoidism
2. Hypogonadism
3. Marfan's syndrome
4. Homocystinuria
5. Klinefelter's syndrome.
Upper Segment > Lower Segment is seen in 
1. Adrenal cortex tumour
2. Precocious puberty.
Lower Segment > Upper Segment is seen 
1. Eunuchoidism
2. Hypogonadism
3. Homocystinuria
4. Klinefelter's syndrome
5. Marfan's syndrome.

How will you clinically differentiate between Marfan syndrome and homocystinuria

Marfan's syndrome is characterised by the following
  • It is a connective tissue disorder
  • It is transmitted as an autosomal dominant trait
  • Bones are normal
  • Mitral valve prolapse and dilatation of the aortic root and sinus of Valsalva may be present
  • There is no mental retardation
  • There is superoateral subluxation of the lens
Homocysinuria is characterised by the folowing
  • It is an inborn error of metabolism, due to lack of the enzyme cystathionine synthase, leading to accumulation of homocystine and methionine and a deficiency of cystathionine and cystine
  • It is transmitted as an autosomal recessive trait
  • Mental defect is present
  • Osteoporosis is present 
  • Medial degeneration of the aorta and elastic arteries may be present
  • Arterial  and venous thrombosis can occur
  • Inferolateral subluxation of the lens is seen