Tutorial 1

 

I think these tutorials would be most useful to 3rd and 4th year Registrars. You need to know a fair bit of dermatology to appreciate the subtle differences between various look alike conditions! The Tutorials should give you a broad overview of clinical dermatology particularly aspects of differential diagnosis. They will use online atlases ,PubMed and eMedicine websites as resource materials as well as the cases in the Dermconsult website itself.

I will illustrate these tutorials better with both a Powerpoint and referral to the Global skin Atlas Website at Global Skin Atlas The format is based on one used by Ken Paver some years ago. Ken set up the Skin and Cancer Foundation in Sydney and was one of the most original and clear thinking dermatologists I have ever met.



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You can view a video of this tutorial below. Any errors then email me at imccoll@ozemail.com.au I think I confuse plane xanthomas and yellow palmar creases with xanthoma disseminatum for starters!



Topics covered in this tutorial

1.DD of the congenital oral leukoplakias
2.DD of erythematous plaques on the cheeks.
3.Lumps on the gums
4.Histiocytosis syndromes
5.Questions on the following conditions-
Gianotti-Crosti syndrome
TORCH syndrome
Pilomatrixoma
Epidermodysplasia verruciformis
Pemphigus vegetans
Juvenile Xanthogranuloma
Rashes of Infectious Mononucleosis
Spitz nevi
Xanthoma disseminatum
Atypical fibroxanthoma
Necrobiotic Xanthogranuloma

THE CONGENITAL ORAL LEUKOPLAKIAS

The differential diagnosis of congenital oral leukoplakias - white sponge nevus, pachyonychia congenita, dyskeratosis congenita, Darier's disease, hereditary benign intraepithelial dyskeratosis.

White sponge nevus is inherited as an autosomal dominant disorder. HPV16 DNA has been identified in some patients. Paradoxically tetracycline antibiotics improve some cases. The lesions can be found in the mouth, the vagina and the rectum Global Skin atlas -Oral Leukoplakia      Image

Pachyonychia congenita - thick nails, palmoplantar keratoderma, follicular keratosis of the skin especially on the knees and elbows, blister formation, palmar and plantar hyperhidrosis and leukokeratosis of the mucous membranes. The condition is inherited as an autosomal dominant, but autosomal recessive forms have also been described. Dermnet Pachyonychia Congenita   
Dyskeratosis congenita - in contrast there are thin nails with a reticulate pigmentation of the back and atrophy. There are also associated ectodermal and mesodermal changes. The reticulated pigmentation may follow the lines of Blaschko.

Hereditary benign intraepithelial dyskeratosis is associated with pingeculae.

Darier's disease is made up of small white papules on the gingival palate or there may be pebbly areas with verrucous white plaques.  

Condition	Typical onset	Oral pattern	Key extra‑oral features
White sponge naevus	Birth–childhood	Bilateral spongy buccal plaques	Often positive family history
Hereditary benign intraepithelial dyskeratosis	Childhood	Corrugated buccal/labial plaques	Recurrent conjunctivitis
Pachyonychia congenita	Infancy–early child	Multiple thick oral plaques	Nail dystrophy, painful plantar keratoderma
Dyskeratosis congenita	Childhood	Leukokeratosis of tongue/buccal mucosa	Nail dystrophy, reticulate hyperpigmentation, marrow failure
Hidrotic ectodermal dysplasia	Childhood	Oral leukokeratosis‑like plaques	Hair/nail changes, palmoplantar keratoderma
Frictional keratosis	Any age	Localized rough plaque at trauma site	Evidence of chewing/trauma
Chronic hyperplastic candidiasis	Early childhood+	Non‑wipeable white plaques	Predisposing immunodeficiency or local factors

HISTIOCYTOSIS SYNDROMES

These are now usually divided into those that are due to a proliferation of Langerhans cells and the others. They include conditions such as histiocytosis X where the acute disseminated form was called Letterer Siwe disease, the chronic progressive was Hand Schuller Christian disease and the benign localised variant was eosinophilic granuloma. The other histiocytic diseases were xanthoma disseminatum, diffuse plane xanthomatosis, juvenile xanthogranuloma and benign cephalic histiocytosis. The latter is usually found on the face and in children less than six months of age and clears often in that time.

 eMedicine-Histiocytosis


This photo is of an elderly lady with histiocytosis.Clinically she was initially thought to have Darier's disease.

ERYTHEMATOUS PLAQUES ON THE CHEEKS Search eMedicine     Search Perplexity AI

Red plaques are caused by infiltrates of cells, substances or bacteria. Look at the causes below. Usually you need a punch biopsy to make a certain diagnosis.

The differential diagnosis of erythematous plaques on the cheeks include lupus erythematosus, Jessner's lymphocytic infiltrate, polymorphous light eruption, granuloma faciale, lymphocytoma cutis, erysipelas, Sweet's syndrome, mycosis fungoides, leprosy, cold injury, amyloidosis and lichen myxedematosus.

Jessner's lymphocytic infiltrate is usually on the peripheral face generally in older males, particularly on the forehead and cheeks with central clearing. It is made up of polyclonal T cells.   Image

Lymphocytoma cutis is usually on the central face, the nose and sometimes the ear lobes. It is usually in young adults. You can sometimes get an epidermal change. Histologically there are usually B cells around lymphoid follicles.

Granuloma faciale is again usually in older men on the nose and cheeks. It can be single or multiple with a peau d orange appearance. It is slow growing and it can vary from skin colour through purple. The histology will show granulomatous infiltration with leukocytoclastic vasculitis.

GSA Granuloma faciale  GSA Sub Acute Lupus   GSA Erysipelas      GSA Lymphocytoma Cutis

This photo shows early discoid lupus

LUMPS ON THE GUMS

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The differential diagnosis of this includes giant cell granuloma, peripheral ossifying fibroma, epulis and pyogenic granulomas.

The term epulis means any benign lesion situated on the gingiva. Most of these are reactive processes with varying degrees of fibrosis, inflammation and vascular proliferation. Giant cell epulis, otherwise known as peripheral giant cell granuloma, is usually found on the gingiva as a bluish red or solitary tumour 1-2cm in diameter near the bicuspids and incisor teeth. Pyogenic granulomas occurring on the gingiva usually occur in pregnancy and may be called a granuloma gravidarum.

 eMedicine-Epulis Fissuratum

The photo below shows an epulis

JUVENILE XANTHOMA GRANULOMA

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This is a benign xanthomatous and granulomatous disease of the skin, the mucous membranes and the eyes. It occurs in crops. It usually appears in the first six months of life. The lesions can vary from 1mm-2mm to 20mm in size. It is sometimes associated with neurofibromatosis and patients may develop myeloid leukaemia. The fats are normal. The eye lesions are usually benign. 75% have solitary lesions.

GSA Juvenile Xanthogranuloma  eMedicine-Juvenile Xanthogranuloma 

XANTHOMA DISSEMINATUM

It is usually seen in males between the ages of five and 25 with yellow brown papules in the flexures and normal lipids. 40% have diabetes insipidus.

eMedicine-Xanthoma       Xanthoma Disseminatum-PubMed

This photo shows the typical yellow papules of Juvenile Xanthogranuloma

PILOMATRIXOMA

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These lesions are usually seen in children on the face and forehead. They are stony hard and sometimes lobulated. They are never malignant. They range in size from 3mm to 30mm. Histologically there are dark staining basophilic cells peripherally with more abundant eosinophilic cytoplasm in the middle of the lesion and bone formation.

GSA Pilomatricoma         eMedicine-Pilomatrixoma

SPITZ NEVI

These are usually red fairly rapidly growing nevi in children with a histology suggestive of melanoma. They are often spindle shaped cells which stream into the dermis in clusters. There is a dilated dermal vasculature but invasion into the upper epidermis does not occur.

 eMedicine-Spitz nevi    Dermoscopy Atlas

The photo below is of a pilomatrixoma

Epidermodysplasia Verruciformis

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These are often flat plane wart like lesions on the face. They may be more verrucous elsewhere. 20% may develop a squamous malignancy usually on exposed areas of the skin. The differential diagnosis is acrokeratosis verruciformis which is an inherited disorder, perhaps a form fruste of Dariers disease with flat wart like lesions peripherally on the hands and feet. Epidermodysplasia verruciformis is inherited as an autosomal recessive. The HPV types involved can be those that are seen in normal hosts as well as some types that are unique to epidermodysplasia verruciformis. There seems to be a defect in cell mediated immunity. The condition usually presents in childhood. As well as the papules in the peripheral areas on the trunk, there are sometimes red plaques or hypopigmented very slightly scaly plaques resembling tinea versicolor. If an SCC develops then radiation therapy is contraindicated. Surgical treatment is best.

GSA Epidermodysplasia Verruciformis         eMedicine- Epidermodysplasia verruciformis



ATYPICAL FIBROXANTHOMA

This is often misdiagnosed as a pyogenic granuloma, but with the histology of sarcoma in an old person often on the lips, face and neck. Common on sun damaged scalps and in immunosupressed patients. Make sure you do an incisional biopsy to show the base to allow the pathologist to distinguish an AFX from a more serious pleomorphic dermal sarcoma.

eMedicine- Atypical Fibroxanthoma              PubMed- Aytypical Fibroxanthoma

The photo below is an atypical fibroxanthoma

NECROBIOTIC XANTHOGRANULOMA

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This is a disease usually of older adults. Characteristically there are periorbital plaques and nodules in about 80% of cases. They may resemble xanthelasmas but they are much deeper, firmer and indurated. They extend into the orbit. The trunk may have plaques that are similar to necrobiosis lipoidica. It is often red in colour with an atrophic centre and superficial telangiectasia. Other eye features include keratitis, uveitis and iritis. There is usually a paraproteinemia.

PubMed-Necrobiotic Xanthogranuloma            Image Diagnosis Case

PEMPHIGUS VEGETANS

This is like pemphigus vulgaris but the edges of the blisters develop hypertrophic features. This is particularly seen around the mouth, the anus and the vulva and also in the flexures. The condition can also be seen in the scalp.

GSA Pemphigus Vegetans     eMedicine-Pemphigus

This is a photo of necrobiotic xanthogranuloma

GIANOTTI-CROSTI SYNDROME

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This condition is sometimes known as papular acrodermatitis of childhood and is probably a better name. Various viruses are involved. Certain viruses are more common in certain areas of the world. It was initially described in association with hepatitis B virus. It generally affects children. The medium age is two. The lesions are erythematous papules or papular vesicles. They are symmetrical on the face, buttocks and extensor limbs sparing the trunk. Note this is in contrast to most viral exanthems which usually affect the trunk. There may be some associated lymphadenopathy. The condition may last one to two months before slowly resolving.

GSA Gianotti Crosti       eMedicine-Gianotti-Crosti

The photos below is an example of the acral extensor papules seen in Gianotti Crosti syndrome

Gianotti Crosti

Gianotti Crosti

Gianotti Crosti

THE SKIN RASHES OF INFECTIOUS MONONUCLEOSIS

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These can be measles like or scarlatiniform, maculo papular, urticarial, purpuric because of thrombocytopenia or even the ampicillin like reaction when Amoxil is given to someone with this disease and a sore throat.

OTHER SKIN LESIONS ASSOCIATED WITH INFECTIOUS MONONUCLEOSIS OR THE EPSTEIN-BARR VIRUS

Some of these have been mentioned already, but other eruptions include a Gianotti-Crosti like. Chronic active Epstein-Barr virus is rare. Two unusual skin eruptions described include a granuloma annulare like eruption and a chronic erythema multiforme like rash. Oral hairy leukoplakia is strongly associated with EBV virus. Oral hairy leukoplakia is commonly seen in AIDS patients but it also occurs in other immunosuppressed hosts especially kidney and bone marrow transplant recipients.

 eMedicine-Infectious Mononucleosis

The TORCH Syndrome - this is seen in newborn infants. Some have blueberry muffin lesions representing cutaneous hematopoiesis. There is often hepatosplenomegaly with jaundice and purpura when the children are examined. Various viruses can cause this including cytomegalovirus and infectious mononucleosis.

GSA Blueberry Muffin baby       eMedicine-Torch syndrome-Cytomegalovirus

The photo below shows the macular Ampicillin induced drug rash seen in Infectious mononucleosis

Ampicillin rash

Ampicillin Rash

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Questions

1. Are the nails thick in dyskeratosis congenita?
2. Lymphocytoma cutis is usually found on the central face in older males?
3. What two conditions may be found with juvenile xanthogranuloma?
4. Diabetes mellitus is a feature of xanthoma disseminatum?
Click SUBMIT below for the answers to these questions. The photo below is of the lesions seen in the Blueberry muffin syndrome

Answers 1. No. They are thin.Thick nails occur with pachyonychia congenita.

2. It is mainly found on the central face but characteristically in younger adults rather than the elderly.  Jessners lymphocytic infiltrate is on the peripheral face in older males.

3. Neurofibromatosis and they may develope myeloid leukaemia.

4. No. It is diabetes insipidus in about 40% of cases.

Tutorial 26

 Topics discussed in this Tutorial

Variants of Discoid Lupus

Erythema infectiosum

Radionecrotic ulcers

Nail tumours

Pilomatrixoma

Phlebectasia

Eccrine tumours

Painful Tumours

Syndromes with Connective Tissue Nevi

Clinical types of Discoid Lupus

There is a vascular type with erythema and normal epidermis with infiltration beneath it so you have rosacea like discoid lupus. You can get a reticulated erythema where you get healing with punctate atrophy and telangiectasia. You can get chilblain lupus. There is also Rowell’s lupus, lupus profundus and there is an arteritic type like Degos disease or a disseminated atrophy blanche type may occur. The hyperkeratotic type can be nodular or plaque form. You can get a localised keratoderma of the foot and sometimes of the nose. The atrophic form presents as an annular erythema with an atrophic centre. It is like morphea. You can also get atrophic spindling of the fingers. The pigmented type can show both hyper and hypo pigmentation. So the four types are vascular, hyperkeratotic, atrophic and pigmentation types. Other variants include umbilicated papules on the back leaving acneiform scars or a red purple mottled plaque or even calcification. Around the eyes you can get conjunctival redness, lid erythema and scaling especially of the lower eyelid. Adnexae may be involved with hair and sweat gland loss. On the lips you can have a cheilitis or rarely oral ulcers as a manifestation of lupus. On nails you can have subungual hyperkeratoses or the red blue colouring of the nail plate showing longitudinal striae and crumbling away of the nail. Some GSA Images

Dermnet on Discoid Lupus

The image below is discoid lupus

Lupus profundus

Erythema Marginatum

There is usually a rapid evolution of the rash over two to three hours. It is not itchy. It can be seen in rheumatoid arthritis or Still’s disease with salmon pink macular or papular lesions on the trunk and extremities.

Dermnet on Erythema marginatum

Erythema marginatum

Erythema Infectiosum and Rubella

Both give buccal red macules. Rubella affects the soft palate. There is a prodrome with red macules. 20% show Forchheimer’s sign. Erythema infectiosum gives slight oedema of the face and it lasts longer than rubella. The lesions in Still’s disease are evanescent, salmon pink and non itchy macules.

The image below is erythema infectiosum

Radio Necrotic Ulcers

The radio necrotic ulcer is very painful. Radiotherapy can cause poikiloderma and watch anything that you are going to do surgically to an old x-rayed area including biopsy because it may not heal. These areas may also develop squamous cell skin cancers. Radiotherapy to the scalp can also induce erosive pustular dermatosis as it attempts to heal.

Dermnet on Radiation Dermatitis

The image below is radiation necrosis scalp

Tumours Found Around the Nail

The common benign lesions are warts, Koenen’s tumours, periungual digital fibromas, a glomus tumour, keratoacanthoma, pyogenic granuloma, subungual epidermoid inclusion, a nevus, subungual exostosis and an enchondroma. The other benign tumour is a myxoid cyst. This will often cause pressure on the nail plate causing a deformity. The malignant tumours are melanoma and SCC.

Periungual fibroma toe

The image below is of a myxoid cyst

Pilomatrixoma

This firm papular lesion can occur in adults. It is usually hard and lobulated. It is normally found in children. There may be occasionally an associated granulomatous reaction if the lesion ruptures. Multiple pilomatrixomas are associated with myotonic dystrophy and the Ehlers Danlos and Gardner’s syndrome.

The image below is a pilomatrixoma of the eyelid

Peutz Jegher Syndrome

There is fading of the extraoral areas of pigmentation at puberty and polyps are usually in the small bowel. They are usually hamartomas.

Cronkite Canada Syndrome

Patients with this condition can get a nail dystrophy as well as marked alopecia and bowel polyps.

Nevus of Ota

In nevus of Ota you have blue lesions on the sclera and black on the conjunctiva.

Phlebectasia

This does not occur at birth. It can occur as late as late as adolescence. Veins thrombose and recanalise with pigmentation and sometimes ulceration.

Florid Oral Papillomatosis

This is a variant of verrucous carcinoma and it can develop into squamous cell  cancer.

Sequences of the Rash in Syphilis

Initially you have macules developing into papules then into papulo squamous lesions. You also can have leukoderma. The lesion never itches and never vesiculates. The nails may present as paronychia. You may get erosions on the tongue and secondary syphilis that looks like geographic tongue.

Dermnet on Syphilis

The image below is of the typical palmar scaly lesions of secondary syphilis

Eccrine Tumours

These include hidrocystoma, apocrine hidrocystoma and hidradenoma, these are usually found on the face and are solitary and slow growing, hidradenoma papilliferum, syringo cystadenoma papilliferum and eccrine poroma. The latter is usually on the feet, has a collarette. It is pink. It may be smooth or warty and there is no pain associated with the lesions.

Hidradenoma

Eccrine hydrocystoma

Multicentric Reticulo Histiocytosis

This condition usually presents as multiple papules on the hands and fingers but it can occur also in the axillae. The lesions are often reddish brown and granulomatous looking. The condition has a specific histology with an eosinophilic ground glass multinucleated cells with surrounding histiocytes and lymphocytes.

Multicentric reticulo histiocytosis

Painful Tumours

Leiomyoma, glomus tumours, spiradenoma, angiolipoma, Schwannoma and chondrodermatitis nodularis helicis. Glomus tumours can be single and painful and in adults or they can be multiple seen in children mainly on the trunk and extremities. They are not painful and can be familial. You may get painful discolouration and sweating before the eruption of glomus tumours.

Glomangioma

Syndromes with Connective Tissue Nevi

1        Tuberous sclerosis   2        Goltz syndrome
3        Buschke-Ollendorf

The latter may present as three patterns

A        PXE like
B        with a thickened plaque plus a few skin coloured nodules
C        with multiple papules all the same size better felt than seen

There often may be other cutaneous manifestations associated with this disease such as striae, keloids and nevi. Note that pseudo xanthoma elasticum is usually found on the flexures.