Examination of skin

What are the functions of the Skin ?

Alterations in colour of skin

Primary and secondary skin lesions

Causes of cutaneous hyperpigmentation

What is melasma or chloasma ?

Cardinal features of addisons disease

What are the cardinal manifestations of hemochromatosis?

Hypopigmentation of skin

Skin lesions that give clue to the underlying diagnosis

What are Neurocutaneous diseases?

What is Cafe au lait spot?

What are the cutaneous signs of internal malignancy?

Cutaneous manifestations of chronic kidney disease

Skin in Hematological Diseases

What are the cutaneous manifestation of Diabetes mellitus?

Cutaneous manifesation of gastrointestinal disease

Cutaneous manifestations of Cardiovascular Diseases

What are the cutaneous markers in Collagen Vascular disease?

Skin in Hematological Diseases

What are the systemic diseases with Pruritus?

What are the cardinal manifestations of hemochromatosis?

What is haemochromatosis ?

It is an iron storage disease that is characterised by increased Intestinal iron absorption.There is deposition of iron in parenchymal cels with tissue damage -The disease is clinically manifested as the following

• Excessive skin pigmentation (due to increased melanin and iron .Melanin is responsible for bronzing of skin
• Diabetes mellitus (bronze diabetes)
• Arthropathy
• Cardiac involvement- Congestive cardia faiure or cardiomyopathy
• Hepatic involvement - Cirrhosis or hepatocellular carcinoma with hepatocellular failure
• Loss of libido and testicular atrophy.

What are the cause of death in Hemochromatosis

• CCF
• Hepatocellular failure
• Hepatocellular carcinoma

What is the treatment of hemochromatosis

• Phlebotomy.
• Iron chelation by desferrioxamme.
• Treatment of CCF. hepato-cellular failure .diabetes mellilus etc.

What are the functions of the Skin ?

• Protection:Skin provide protection from  Physical, Chemical, Infections agents
• Thermoregulation: Blood vessels and Eccrine sweat glands are involved in thermoregulation
• Homeostasis of water, electrolytes and protein
• Lubrication and waterproofing: Sebum secreted by sebaceous glands
• Sensations - specialized nerve endings act as sensory organs
• Immunological: Lymphocytes, macrophages, Langerhans cells are involved in immunity
• Synthesis of vitamin D by keratinocyte
• Body odour: Apocrine glands produce body odour
• Protection and prising: Nails are involved in this function
• Calorie reserve: Subcutaneous fat preserve body heat
• Psychosocial: Cosmetic functions -skin, lips, hair, nails.

What is melasma or chloasma ?

This is a frequently seen hyperpigmentation in young females

It is rare in males

Chloasma may be frequently precipitated by pregnancy also called as Chloasma gravidarum or mask of pregnancy

They may be precipitated by oral contraceptive pills

The pigmentation is generally seen on the malar prominence and bridge of nose

They are frequently symmetrical

Cardinal features of addisons disease

Following are the cardinal features of Addison s disease

Commonly the patient is female and suffers from :

• Asthenia,hypotenstion.hyperpigmentation are the major manifestations

The minor manifestations are

• Anorexia, malaise, weight loss.
• Decreased body hairs
• Hyperkalaemia.
• Hvpoglycaemia
• Nausea, vomiting.
• Chronic fatigue syndrome.
• Acute adrenal crisis.

Pigmentation in addison's disease .

• Pigmentation in addisons disease is due to increased pituitary MSH andACTH secretions
• Initially there is tanning after exposure to the sun.
• Later there is tanning noticed pressure points (elbow).
• Normally  pigmented areas like areola ,knuckles palmar creases and scars become more pigmented
• Mucous membrane pigmentation can occur (genitals and oral cavity)
• There may be areas of vililigo

Differentiation between primary and secondary adrenocortical insufficiency

In primary (Addison s disease) cases, there are features of.

• Absence of hypothyroidism and hypogonadism
• High plasma ACTH level.

In secondary hypofunction, there are :

• Absence of pigmentation.
• Presence of hypothyroidism and hypogonadism
• Low plasma ACTH level.

What are the systemic diseases with Pruritus?

Pruritus is a prominent symptom in the following illness

• Obstructive jaundice
• CRF
• Diabetes mellitus
• Hypothyroidism
• Hyperthyroidism
• Polycythemia vera
• Internal malignancy-lymphoma, myeloma
• Carcinoid syndrome
• Psychosis

Skin lesions that give clue to the underlying diagnosis

Certain skin lesions are important as they give clue to some underlying illness

Purplish striae is seen over the lower, anterior abdominal wall in Cushing's syndrome.

Erythema marginatum is a cutaneous sign in rheumatic fever.

Purpuras, ecchymosis are seen in ITP, Henoch-Schonlein purpura, coagulation defects, Leukemias.

Adenoma sebaceum ,Shagreen patch and  Ash leaf macules are seen in Tuberous sclerosis

Hemangiomas present externally may also be present in the CNS.

Telangiectasia are seen in ataxia telangiectasia .Multiple telangiectasias are seen in Osler-Rendu Weber syndrome.

 Osler-Rendu Weber syndrome there is AV malformations  found in

• Lung
• Liver
• CNS 
• Mucous membranes.

Spider naevi indicate decompensated liver disease ,SVC obstruction.

Palmar erythema is seen in

• Decompensated liver disease
• Chronic febrile illness
• Chronic leukemias
• Polycythemia 
• Rheumatoid arthritis  
• Thyrotoxicosis
• Chronic alcohol intake 
• Physiological states like pregnancy.

Erythema nodosum  is a nonspecific skin marker and it may be seen in conditions like primary complex, sarcoidosis and with certain drugs

Multiple neurofibromas are seen in von Recklinghausen's disease

Xanthomas indicate underlying Hyperlipidemia

Malignant tumours of the skin are Squamous cell carcinoma, basal cell carcinoma, malignant melanoma.

Pigmentation of the mucous membrane of the oral cavity is seen in

Addison's disease, and in Peutz-Jeghers syndrome which is associated with perioral pigmentation and polyposis of colon.

A tuft of hair or a lipoma over the lower lumbar region in the back may give clue to the presence of spina bifida.

Cutaneous manifesation of gastrointestinal disease

• Pigmentation of peri oral lips and hand is seen in Peute Jegher s syndrome
• Derma1 cyst-Gardener's syndrome
• Pyoderma gangrenosum-ulcerative colitis
• Dematitis herpetiformis –Gluten sensitive enteropathy
• Eczematous lesion of acral parts-acrodermatitis enteropathica
• Cirrhosis liver is characterised by pruritus ,Palmar erythema, purpura and jaundice
• Migratory thrombophlebitis-Ca head of pancreas-Trousseau's syndrome
• Dermatomyositis-GI malignancy
• Pityriasis rotunda-Hepatocellular carcinoma, hyperpigmented scaly lesions over trunk and thighs.
• Palmar tylosis-Ca esophagus'
• Necrolytic migratory erythema-glugonoma
• Flushing of skin-carcinoid syndrome.

Cutaneous manifestations of Cardiovascular Diseases

Infective endocarditis is characterised by 

• Osier's nodes
• Janeway lesions

Rheumatic fever has the following cutaneous manifestations

• Erythema marginatum
• Erythema nodosum
• Subcutaneous nodules

What are Neurocutaneous diseases?

Cutaneous manifestations that are characteristic of certain neurological disease are described here

Tuberous sclerosis  is characterised by the following lesions

• Adenoma sebaceum/Angiofibroma of face 
• Subungual  fibroma
• Shagreen patch
• Leafy macule

Von Recklinghausen's disease

• Multiple cutaneous and subcutaneous neurofibroma
• Cafe-au-lait spots > 6 in no: >1.5 cm in size
• Axillary freckles

Sturge Weber syndrome

Capillary hemangioma in trigeminal nerve distribution is seen in Encephalo-trigeminal angiomatosis

Hereditary hemorrhagic telangiectasia

There is multiple telangiectasia of skin, mucosa, and pulmonary system

Hypopigmentation of skin

Generalised absence of skin pigmentation is seen in Albinism 

Following are the syndromes with albinism

Chediac higashi syndrome also called as phagocytic deficiency disease

Phenylketonuria a condition characterised by inborn error of metabolism

Patchy absence of skin pigmentation may be due to Vitiligo which is seen in 

• Idiopathic cases
• Autoimmune disease
• Thyroid disease
• Pernicious anemia

In the presence of vitiligo always rule out immune causes in that patient

What are the causes of Hypopigmented Lesions

• Early vitiligo
• Leukoderma-early
• Hansen's disease
• Nevus anemicus
• Leafy macules-tuberous sclerosis
• Tinea versicolor
• Pityriasis alba

Circumscribed hypopigmented lesions of the skin may be seen in Hansens disease ( Tuberculoid or Borderline Tuberculoid types) and Tinea versicoior.

Causes of cutaneous hyperpigmentation

Patchy hyperpigmentation of the skin is seen in 

• Pellagra on exposed part to sunlight
• Porphyria cutanea tarda
• Scleroderma
• Chloasma
• Butterfly rash on face of sle
• Acanthosis nigricans
• Fixed drug eruptions
• Drugs like Chlorpromazine, crofazimine,heavymetals like bismuth and gold

Acanthosis nigricans is a pigmented velvety thickening of skin

Types of Acanthosis nigricans

• Benign type is seen in - Obesity, Cushing's syndrome, drugs-OCP, nicotinic acid, protease inhibitors
• Malignant type seen in Internal malignancy

Megaloblastic anemia-hyperpigmentation of hands and face can be seen

Haemochromatosis

Endocrine disorders

• Addison's disease
• Cushing's syndrome
• Ectopic ACTH production.
• Nelson's syndrome is seen in post adrenelectomy cases

Arsenic poisoning

Common causes of hyperpigmentation are

• Familial, racial.
• Sunburn. 
• Addison'sdisease
• Hemochromatosis
• Peutz-Jeghcrs syndrome.
• Chronic kala-azar.
• clofazimine (red), busulphan.
• Pellagra.
• Chronic arsenical poisoning.
• Facial pigmentation in chloasma or melasma. SLE
• Porphyria (cutanea tarda) 

What are the sites examined for increased pigmentation :

• Face.
• Inside the oral cavity, specially cheeks and palate 
• Palmar creases
• General skin surface 
• Pressure points
• Normally pigmented area like areola
• Sun exposed area
• Recent scars
• Palms and sole

What are the cutaneous signs of internal malignancy?

Intemal malignancy may have the following cutaneous maniesations

• Acanthosis nigricans is seen in adenocarcinoma of GIT
• Palmo-plantar keratoderma is the thick hard hyperkeratotic skin seen in carcinoma bronchus and oesophagus 
• Necrolytic migratory erythema is seen in glucagonoma
• Pityriasis rotunda seen in association with hepatocellular Carcinoma
• Sign of Leser-Trelat is the sudden eruption of intensly pruritic multiple seborrhoeic keratosis in Carcinoma stomach
• Migratory thrombophlebitis is a sign of Carcinoma  pancreas
• Cutaneous hamartoma are seen in carcinaoma  breast, thyroid, gastrointestinal polyposis-cowdens disease
• Pellagra like skin lesions are seen in Carcinoid syndrome
• Pruritus is seen in association with Lymphoma, polycythemia vera
• Dermatomyositis  can be seen in GI malignancy.

Cutaneous manifestations of chronic kidney disease

Certain skin changes are seen in patients with chronic renal failure

• Uraemic frost
• Erythema papulaturn uraemicum are erythematous nodules over palms, soles and forearm 
• Generalized pruritus
• Kyrle's disease is characterised by multiple discrete or confluent hyperkeratotic follicular papules over lowerextremities
• Nail changes (half-half nail—proximal white and distal half pink, mees lines are the nail manifestation of CKD
• Oral manifestations (coating of tongue, xerostomia, ulcerative stomatitis).
• Metastatic calcification

What are the cutaneous markers in Collagen Vascular disease?

Manifestations of SLE

• Butterfly rash
• Telangiectasia

Polyarteritis nodosa and anti-phospholipid syndrome

• Livido reticularis
• Purpura

Dermatomyosistis

• Heliotropic rash
• Periorbital edema
• Gottron's papules

Skin in Hematological Diseases

Following are the cutaneous manifestations of haematological disease

Hyperpigmentation in megaloblastic anemia

Urticaria after hot water bath and palmarerythema is seen in polycythenria vera

Painful ecchymosis at the site of minor trauma is called autoerythrocyte sensitization syndrome sensitization to extravasated RBCs 

Cutaneous bleeds are classified as given below

• Petechiae < 2 mm size
• Purpura   2-5 mm size
• Ecchymosis > 5 mm size 

What are the cutaneous manifestation of Diabetes mellitus?

Diabetes mellitus is associated with following cutaneous manifestation

• Necrobiosis lipoidica diabeticorum is characterised by papulonodular lesions enlarging to form brownish yellow plaques with waxy surface over the front of legs.
• Diabetic dermopathy are  dull red, oval, flat-topped papules over both legs
• Diabetic bullae are seen the over legs, hands and feet bilaterally and  healing with atrophic scars.
• Diabetic rubeosis is the flushed skin of face.
• Scleredema diabeticorum is a diffuse, waxy nonpitting induration_of skin particularly over back of the neck and upper trunk
• Carotenoderma is the yellowish tint of skin due to deposition of carotene
• Granuloma annulare is characterised by the papular lesion over central areas of body and flexures of neck, arm and thigh.
• Infections like furuncle, carbuncle, candidalparonychia, balanoposthitis, intertrigo, recurrent dermatophytosis are common in diabetic patients

What is Cafe au lait spot?

Cafe au lait spots are macule that are seen in more than 90 percentage of people with Neurofibromatosis Type 1 and 2

• They appear as light brown round to ovoid macules with smooth borders often located over the nerve trunk with their long axis parallel to the cutaneous nerves
• It is significant when the number is more than 6 and each more than 1.5 cm in diameter 

Cafe au lait macules are also seen in McCune-Albright syndrome.
They differ from neurofibromatosis in the following

• They have irregular borders 
• They are seen in the midline

Alterations in colour of skin

Alterations in colour of skin is seen in following conditions

Pigmentation of skin vary from dark skinned to fair individuals depending on the race to which they belong

Pale skin -Pallor

Is seen anemia, hypopituitarism, CRF

In pallor the patient appears pale,it is seen over the skin, mucous membranes, lower palpebral conjunctiva, finger nails and palms of thehands. Loss of pigmentation of the palmar creases of the hands gives a clue that the Hb may be less than 7 gm% .

Bluish discoloration—cyanosis

Yellowish—jaundice

Yellow pigmentation of the skin is seen in 

• Jaundice is the yellowish discoloration of the skin ,mucous  membranes' and the sclera seen  when the serum bilirubin exeeds 2mg percentage
• Carotenerma is due to excessive ingestion of carotene.It is associated with yellowish discolouration of skin and mucous membrane but sparing sclera
• Lemon yellow discotoration of skin may be  seen in long standing severe anemia

Generalised Hyperpigmentation of skin 

Flushing of Skin (facial plethora)is seen in 

• Chronic alcoholism.
• Cushing's syndrome
• Polycythemia
• SVC syndrome
• Chronic cor pulmonale.
• Carcinoid syndrome

Primary and secondary skin lesions

Skin is a mirror of systemic disease. Examination of skin will reveal specific sign of systemic disease.
Skin lesions can be classified as 
Primary skin lesions

• Macules are flat lesions < 1cm circumscribed alteration of color of skin <1cm
• Papules are palpable solid elevation < 1cm .Maculopapular rash include both macule and papule
• Plaque are papular lesions of size > 1cm
• Patch is a circumscribed alteration of color of > 1cm.
• Vesicles are lesions < 1 cm these are fluid filled epidermal elevations.
• Bullae are > 1cm fluid filled elevation 
• Pustules are epidermal elevations < 1cm containing pus
• Nodule areSolid palpable lesion ->0.5 cm
• Papilloma - Pedunculated projecting lesion
• Wheal - Elevated central white lesion with red margin
• Telangiectasia - Dilated small cutaneous blood vessel
• Petechiae - Pinhead size macule of blood into the skin.
• Purpura -Larger petechiae which do not blanch on pressure
• Ecchymosis -Large extravasation of blood into resulting in  haematoma 
• Erythema - Redness of the skin.

Secondary skin lesions are the following

• Scales—Desquamated epithelium
• Ulcers—Loss of epidermis, dermis and often with loss of underlying tissue
• Crust are dried up exudates
• Scar are replacement by fibrous tissue
• Excoriation are Loss of skin substance produced by scratching
• Fissure—Any linear slit or discontinuity of skin.