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Showing posts with label hair examination. Show all posts
Showing posts with label hair examination. Show all posts

Hypertrichosis -clinical significance

Hypertrichosis is a condition where there is excessive growth of hair in generalized or localized pattern but this is not of male pattern of distribution.
Congenital hypertrichosis is seen in porphyria cutanea tarda, 
Hurler's syndrome, 
Giant pigmented naevus also called as [bathing suit naevus]
Acquired hypertrichosis is seen in the following conditions
  • Malignancy-bronchogenic carcinoma
  • Drugs-phenytoin, steroids,minoxidil, diazoxide, streptomycin.
  • Endocrine causes
  • Sexual precocity
  • Hypothyroidism
  • Adrenal hyperplasia or neoplasm


Examination of hair

The scalp contains approximately 1,00,000 hairs.Each hair grows for about 1,000 days.
Rate of hair loss per day is approximately 100 normally.
Examination of hair consists of:
  • Distribution-normal or abnormal
  • Color of hair
  • Alopecia
  • Hypertrichosis
  • Hirsutism


Causes of hypertrichosis

Hypertrichosis is a condition where there is excessive growth of hair in generalized or localized pattern but this is not of male pattern of distribution.
Congenital hypertrichosis is seen in porphyria cutanea tarda, Hurler's syndrome, giant pigmented naevus also called as [bathing suit naevus]
Acquired hypertrichosis is seen in the following conditions
Malignancy-bronchogenic carcinoma
Drugs-phenytoin, steroids,minoxidil, diazoxide, streptomycin.
Endocrine causes
  • Sexual precocity
  • Hypothyroidism
  • Adrenal hyperplasia or neoplasm
Hirsuitism
Increased growth of terminal hair in women similar to  male secondary sexual pattern.
Causes of hirsuitism are 
  1. Idiopathic
  2. Virilization in adrenal and ovarian tumors
  3. Corticosteroid therapy





Causes of Greying of hair

Graying of hair can be seen as part of  Aging process
Starts at an age >20 in whites and at an age > 30 in black
Poliosis is the presence of grey hair in circumscribed pattern
What are the causes of premature graying of hair?
  • Megalobastic anemia
  • Diabetes mellitus
  • Hyperthyroidism
  • Dystrophia myotonica
  • Rare syndromes like Werners syndrome ,Vogt Koyanagi syndrome, Waardenbure syndrome, Chediak-Higashi syndrome.
Flag sign is the brownish discolouration of hair, with interspersed normal colour of hair, is seen
in protein energy malnutrition

What are the causes of alopecia?

Alopecia is the loss of hair from skin. It is of 2 types
Non-cicatrical alopecia and Cicatrical alopecia 
Causes of Non-cicatrical alopecia 
Physiological alopecia also called as male pattern of alopecia
Physiologic androgenic alopecia is an autosomal dominant male pattern of baldness,there is bitateral pattern of hair loss and is usually familial. 5-alpha reductase inhibitor finasteride is useful in the treatment. Other causes are puberty, pregnancy and neonatal period.
Alopecia areata is the most common type of noncicatricial alopecia.It is a autoimmune disease characterised by single or multiple areas of alopecia without any inflammation.
If it involves the whole of the scalp it is called atopecia totatis 
If it involves the whole of the body it is called atopecia universalis
It is associated with other auto immune disease like  SLE, vitiligo, autoimmune haemolytic anemia
Systemic diseases that produce alopecia are 
  • SLE
  • Hyperthyroidism
  • Hypothyroidism
  • Acrodermatitis enteropathica
  • Pernicious anemia 
  • Down's syndrome.
Infection: Moth eaten type of alopecia is seen  in syphilis and fungal infections.
Drugs: Antimetabolites, Cytotoxic agents, Carbimazole, Iodine, Bismuth, Vitamin A and Amphetamines. 
Telogen effluvium: is the hair loss following systemic illness (typhoid, measles, pneumonia) postpartum and postsurgical cases.
Radiation.
Alopecia in females  seen in virilising tumor of ovary or adrenal
Causes of cicatricial Alopecia
It is due to primary dermatological conditions
  • Trauma
  • Burns
  • Folliculitis, gumma, lupusvulgaris and herpes zoster
  • Morphea, lichen planus, saroidosos and DLE
  • Drugs-Mepacrine.
Decreased Body Hair Distribution (Loss of Secondary Sexual Character)
This is seen in the following conditions:
  • Decompensated liver disease
  • Klinefelter's syndrome
  • Bilateral testicular atrophy as seen in Hansen's disease.