Topics discussed in this Tutorial
Leprosy
Alopecia mucinosa
Tertiary Syphilis
Skin lesions in Rheumatoid Arthritis
Folliculitis decalvans
Erythema and pain
DD of Pyogenic granuloma
Mucinoses
Red and Painful Plaques DD
Localised pustular psoriasis
Epidermal nevus syndrome
Acrocyanosis
Rapidly growing lesion
Another session on Leprosy
Tuberculoid Leprosy involves macules, papules at the edge, a sharp outer edge fading in the way, the colour may be hypopigmented, purplish or red, no sweating, there is a reduction in sensation, there is no hair. You can have palpable nerves. There are a few lesions only and they are usually asymmetrical.
Borderline tuberculoid in contrast has papules with a central clear area but a sharp inner area and it flattens to the outside. It is symmetrical and there are more patches.
Indeterminate leprosy is macular, pink or white.
Borderline leprosy may have palpable nerves as well as nodules. Borderline lepromatous may have palpable nerves as well as nodules and lepromatous can have nodules, infiltrated plaques and in the late stage white macules.
The image below is of tuberculoid leprosy
It is usually seen in women, post puberty. It involves the axillae. There is itch at first in areas of apocrine glands and subsequent domed papules with pigmentation of the papules.
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| Fox Fordyce disease |
The acute benign variant has erythema scale and acute papules. The chronic variant is more widely distributed with plaques. Mucinous MF variants are seen as plaques on the head and neck, usually grouped, can be scaly flat areas like psoriasis and usually have patulous follicles, which may secrete a clear material.
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| Benign alopecia mucinosa |
Tertiary Syphilis
It is usually the nodular tuberculoid type, flat and serpiginous and then there is the gummatous type. Differentiate a gumma from pyoderma gangrenosum. A gumma is usually painless and chronic and pyoderma gangrenosum is painful and acute. Remember that sarcoidosis can be scaly.
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| Tertiary syphilis |
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| Tertiary syphilis abdomen |
Skin Lesions in Rheumatoid Arthritis
Bywaters lesions involve the nail fold and last a few days. They are also seen in lupus erythematosus. You can get purpura, ulcers, rheumatoid nodules, linear bands, sclerotic changes, pyoderma gangrenosum and the various complications of treatment. There is an acute rash, which is like Stills disease. In males you get a sensory and motor neuropathy.
Folliculitis decalvans involves the scalp and other areas. It is seen in middle-aged women. Slow in men. Usually unilateral.
This is lichen planus of the scalp.
Keratosis Pilaris Atrophicans
This is seen in children and it may involve the eyebrows causing scarring and hair loss.
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| Folliculitis decalvans |
Grouped Micro papules
The diagnosis is keratosis pilaris, lichen spinulosus, lichen scrofulosorum, perforating granuloma annulare, sarcoidosis, lichen nitidus, lichen plano pilaris and follicular mucinosis.
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| Follicular mucinosis neck |
You can have primary or secondary. Secondary is due to polycythemia rubra vera and thrombocythemia.
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| Erythromelalgia hands |
Erythema and Pain
Consider thromboangiitis obliterans, erythromelalgia and atherosclerosis. Night pain in seen in both Burgers syndrome and atherosclerosis. In ischemic pain you may have nerve loss as well with trophic skin changes.
It can present as a plaque with orange.peel like surfaces. It can be diffuse and extend down to the foot and it can be elephantine.
The Differential Diagnosis of Pyogenic Granuloma
There are five malignancies and five hyperplasias. The five malignancies are metastasis, Kaposi’s sarcoma, amelanotic melanoma, BCC and spitz nevi. The five hyperplasias are angio lymphoid hyperplasia, pseudo pyogenic granuloma, atypical fibroxanthoma, pyogenic granuloma with surrounding satellite lesions and inflamed seborrhoeic keratosis. Pseudo pyogenic granulomas are found in patients being treated with Retinoids. They are multiple, small and sessile. Telangiectatic epulis is pyogenic granuloma on the lip. Pyogenic granulomas show little collagen but vascular proliferation and a lot of mucin.
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| Pyogenic granuloma in pregnancy |
They are classified as being localised, generalised or syndromal. The localised ones are things such as myxoid cysts, papular mucinosis, pretibial myxoedema, reticular erythematous mucinosis and follicular mucinosis. The generalised ones are lichen myxodermatosis, scleromyxedema, myxoedema and scleredema. There are other diseases such as lupus erythematosus that may form mucin. The syndromes are Hunter’s and Hurler’s syndrome, Morquios in which there is generalised telangiectasia, Leroy’s which is like Hurler’s but no corneal opacities. In the mucinoses look for ivory white nodules or ridges in symmetrical areas between the angles of the scapula and the posterior axillary lines. They may be 1 to 10mm in size, it is usually seen in Hunter’s syndrome, which has cloudy corneas in 90% of cases and is an x linked recessive.
The image below are the sipndled fingers of Scleromyxedema
The Differential diagnosis of Red and Painful Plaques
Consider erysipelas, erysipeloid, cellulitis, necrotising fasciitis, malignancy and a streptococcal gangrene. In erysipeloid you have a circumscribed dull erythema, it is self-limiting. In necrotising fasciitis you have localised anaesthesia surrounding the area within it. Consider also Sweet’s syndrome, familial Mediterranean fever where the red painful plaques involve the legs. The Vitamin K injection reaction where there is no pain. Consider also lupus and vasculitis. Well’s syndrome or Eosinophilic cellulitis tends to have a greenish plaque or a greenish tinge above the plaque and malignant angioendotheliomatosis have plaque like erysipelas but then they develop into nodules. It particularly involves the face in older people. It can look more bruise like.
The image below is a patch of erysipeloid
Localised Pustular Psoriasis
It can be circinate as in Reiters. It can be acropustulosis of Hallopeau. You can get an annular erythematous form which looks like erythema annulare centrifugum but it is going to have pustules on the edge. You can get an ordinary psoriatic plaque with pustules. You have the palmar plantar pustulosis, you have napkin pustular psoriasis and you can also have an exanthematous type that may be drug induced but it tends to be more generalised rather than localised.
This image is acrodermatitis continua of Hallopeau
Localised pustular psoriasis feet
Some Other General Points
A malignant blue nevus usually comes from the cellular variety, may be present at birth and it is often flat rather than raised.
A myxoid cyst is usually traumatic around the DIP joint and may involve the nail matrix causing a deformity of the nail plate.
Pigmented basal cell skin cancer has a pearly edge and is well defined. It can be seen in arsenic ingestion, it is usually on the back but also consider it in the basal cell nevus syndrome.
A thrombosed haemangioma looks like a superficial spreading melanoma but remember it has been red before it became thrombosed.
You have a nasal tumour. Consider a myxoma, which may be a fibroma with mucin in it.
Watch also children with dome shaped tumours on the scalp or even over the spine centrally. It can be a central glioma on the scalp with ectopic brain in it, so do not stick a punch into it.
Comparing Nevus Spilus with Capillaritis
In a nevus spilus it is flat with a background café au lait spot with speckled pigmentation. Capillaritis can have some speckled pigmentation but there is no background café au lait spot and there may be some punctate bright red recent haemorrhage.
If you are comparing Bowen’s and a superficial spreading BCC watch for the edge of the BCC. It is a pearly edge and Bowen’s does not have it.
Café au Lait spots
You will see them in neurofibromatosis and Albright’s syndrome. The edges of them are much more irregular in Albright’s.
Generally the epidermal nevi associated with this are larger. They are seen on the scalp and face. The patient may have had epilepsy or some unilateral ocular syndrome. They sometimes can have underlying bone problems. Nevus sebaceous occurs particularly in the scalp area. It has a yellowish colour and often rounded papules associated with it compared with an epidermal nevus. Basal Cell carcinoma or a forme fruste called trichoblastoma, can develop in these lesions along with syringocystadenoma papilliferum.
This is an extensive Epidermal nevus under the breast.
Extensive sebaceous nevus scalp
Three Diseases with Erythema, Bullae and Hyperkeratosis
Consider bullous epidermolytic hyperkeratosis where there is no pigment. Incontinentia pigmenti where there is no erythema and Conradi’s syndrome where there are no bullae and ichthyosis usually clears in the first year of life.
Ichthyosis hystrix is the porcupine man. Nevus unius lateralis is a linear epidermal nevus on one side of the body following Blaschko’s lines.
The Differential Diagnosis of Acrocyanosis
Acrocyanosis occurs in a young person. It is symmetrical, may be familial, it is persistent. Erythrocyanosis is typically seen over fat and there may be associated follicular erythema seen in the forearms in infants, the buttocks in young boys and the legs in fat girls and it may also show the Koebner phenomenon. Erythromelalgia is not cyanotic, it is red and other diseases associated with it include polycythemia rubra vera. Secondary erythromelalgia can be seen with system lupus with associated hypertension and diabetes. Rowell’s syndrome is discoid lupus or systemic lupus with perniosis and erythema multiforme. In disseminated intravascular coagulation you get cyanosis initially. Lupus pernio can give a cyanotic presentation particularly in the nose and the ears. It is a form of sarcoidosis and there may be underlying bone and lung problems.
Chilblain lupus. This can occur years after damage to the peripheries. It may evolve into systemic lupus. Acral ischemia can also give rise to erythermalgia like lesions and peripheral cyanosis.
These toes show the features of Chilblain Lupus.
A Rapidly Growing Lesion
It can be a sarcoma or a secondary tumour or a keratoacanthoma. A neuroma is a painful tumour. A granular cell myoblastoma occurs particularly on the foot or the tongue. It has a very striking pathology with large pale cells with a granular cytoplasm and fibroblasts are squeezed between the cells.
Other Causes of Red Plaques
Sweet’s syndrome where you get erythema and plaques on the hands over the knuckles with arthritis, dermatomyositis erysipeloid and malignant angioendothelioma. The latter has two types. There is a type on the scalp of the elderly and there are young people where it is usually paranasal. Note also rosacea. There is no involvement of the folds in rosacea. The papules are not tender and they are perifollicular compared with acne where the papules are tender and in lupus erythematosus the folds of the face are often involved.
Episodic Facial Flushing
It can be emotional, menopausal, alcohol, pheochromocytoma, Cushing’s disease, rosacea, mastocytosis or drugs. There is also the rare Zolinger Ellison syndrome. Facial flushing can also occur in hyperthyroidism. One sided facial flushing can be due to the Sphenopalatine syndrome with rhinitis. The auricular temporal syndrome with hyperhidrosis and the ciliary syndrome with pain lacrimation and headache.
The image below is a Granular Tumour on the forearm
