Topics discussed in this Tutorial
The difference between Necrobiosis and Necrosis
Sclerodermoid changes in the skin
Secondary syphilis
Kawasaki Syndrome
Comparing Dyskeratosis congenital and Pachyonychia congenita
Mucopolysacharidoses
Congenital syphilis
Peg teeth
Ectodermal dysplasias
Neurofibromatosis and Tuberous Sclerosus
Dyskeratosis Congenita/Fanconi’s anaemia/Naegeli’s Syndrome
Poliosis
The Difference between Necrobiosis and Necrosis
Necrobiosis means physiological death and necrosis means pathological death. Necrobiosis lipoidica diabeticorum near the hairline gives no atrophy or scarring. The differential diagnosis of NLD includes granuloma annulare, morphea, panniculitis, xanthomata. Note also that diabetic dermopathy does not scar. They still have hair follicles whereas the hair follicles are lost in necrobiosis lipoidica and there may sometimes be comedones in necrobiosis lipoidica.
The image below is necrobiosis lipoidica
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| Diabetic dermopathy It is often paler than this. |
Sclerodermoid Changes in the Skin
On the face these can be due to xanthosidero histiocytosis. This gives a greenish tinge and it looks like scleroderma. The carcinoid syndrome can also give an sclerodermoid change as can PCT which gives a violaceous colour like Cushing’s and also a condition called rhomboidallis cutis frontalis. Sclerodermoid features are also seen in late stage graft versus host disease. Porphyria cutanea tarda in the scalp may scar and the differential diagnosis is necrobiosis lipoidica and lupus.
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| Sclerodermoid PCT chest |
The Flushing Syndromes
Carcinoid and mast cell disease give flushing that mainly affects the limbs but I still consider it most with severe prolonged facial and upper chest flushing with varying colours. Pheochromocytoma particularly occurs around the menopause with hyperhidrosis. You get over breathing with the carcinoid syndrome.
The Colour of Lymphomas
B-Cell lymphomas are usually reddish whereas T-Cell lymphomas such as mycosis fungoides are often violaceous. Lymphocytoma Cutis can be polymorphic and very rarely will it scale whereas Jessners is never polymorphic and it never scales.
Inherited Ichthyotic Disorders and CNS Features
Sjogren Larsen gives spasticity and Refsum’s disease gives ataxia.
The image below is a B cell lymphoma
Note such unusual features such as a nocturnal headache. Also the papules come inside the macules and then they gradually become more papular as the immunity changes and that is what causes the morphological change.
Oral Lesions of Syphillis
You get the snail track ulcers, there is a loss of papillae on the tongue and there is a glossitis.
The image below is of secondary syphilis
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| Oral lesions of secondary syphilis |
Comparing Dyskeratosis Congenita and Pachyonychia Congenita
In dyskeratosis congenita you get aplastic anaemia and paronychia. You will get hyperhidrosis in both pachyonychia congenita and dyskeratosis congenita. Both also give oral leukoplakias. The nail bed is also involved in pachyonychia congenita with hyperkeratosis but the matrix is involved with grossly thickened nails like hooves. Dyskeratosis congenita starts at ages 5 to 15 and damage to the matrix gives a sort of sticking up plug like deformity of the nail.
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| Pachyonychia congenita nails |
You get a glove and stocking type erythema and you also get oedema of the hands and feet with a red tongue. It may also classically give a buttock erythema.
Compare and Contrast Scleromyxedema versus Scleroderma
In scleromyxedema the skin is thickened but it is moveable on the subcutis whereas in scleroderma the skin is bound down and it is not moveable
The image below is scleromyxedema
The Inherited Mucopolysaccharidoses - Compare Hurler’s Syndrome with Hunter’s Syndrome
In Hurler’s syndrome it is an autosomal recessive with cloudy corneas. In Hunter’s syndrome it is an x linked with clear corneas and ivory white nodules arranged in rows on the lateral trunk.. The San Filipo also has a clear cornea. All the other mucopolysaccharidoses have cloudy corneas.
The image below is of Hurler's syndrome
It may present :
a. With disease in which case the antibody tests will be positive. The child may look apelike with yellowish skin, rhinitis, the skin features of secondary syphilis and also a mild paronychia.
b. Secondly it may present as a latent stage with no obvious features. The standard treponemal tests are positive in about 60% of cases.
c. Or it may present as the late stage where it presents with an interstitial keratitis, synovitis, bone changes especially affecting the nose or sabre tibia and often 8th nerve deafness with optic atrophy and paroxysmal cold haemoglobinuria.
The other features associated with congenital syphilis presenting with disease are osteochondritis, syphilitic dactylitis, hepatitis splenomegaly and meningitis. The stigmata of congenital syphilis are notched incisors and mulberry molars. Hutchinson’s triad is interstitial keratitis, Hutchinson’s teeth and 8th nerve deafness. Optic atrophy in a young person should arise suspicions of congenital syphilis.
A good way of looking at the term gumma is a boil that does not hurt. The serology of congenital syphilis, if it is IGM positive then treat, if there is a rising titre then treat. Titres are usually negative by three months if they have been there in the first place because of passive transfer from a treated mother.
The image below is of secondary syphilis
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| Secondary syphilis palms |
This can be seen in congenital syphilis, anhidrotic ectodermal dysplasia, incontinentia pigmenti and chondroectodermal dysplasia. Chondroectodermal dysplasia is an achondroplastic dwarf with six fingers. They have peg teeth and nail abnormalities.
Dermnet on the Ectodermal dysplasias
The treponnema pallidum immobilisation test is positive in late primary syphilis. It is always positive and it distinguishes a biological false positive. The treponemal pallidum antibodies are very sensitive and they are seen earlier than the VDRL test.
The image below is of Anhidrotic ectodermal dysplasia and peg teeth
The similarities are poliosis, café au late spots, mental deficiency, pedunculated fibromas, collagenous nevus and a high spontaneous mutation rate. The endocrine problems associated with neurofibromatosis include phaeochromocytoma, acromegaly, hyperparathyroidism, gynecomastia and precocious puberty.
The clinical types you can see include molluscum fibrosum, plexiform neuromas and elephantiasis neuromatosa. Crowe’s sign is axillary freckling. There may be an association with juvenile xanthogranuloma. Oral lesions are seen in 5% to 10% of cases. Kyphosis in 10%. Neurological abnormalities in 40%. Sarcomatous change may occur in 5% to 15% of cases but it is rare before the age of 40.
The image below is of Tuberous Sclerosus
Dyskeratosis Congenita/Fanconi’s anaemia/Naegeli’s Syndrome
These all have reticulate pigmentation in the new born period.
See also Reticulate pigmentation of Kitamura
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| dyskeratosis congenita |
The image below is reticulate pigmentation of Kitamura
The Differential Diagnosis of a Breast Dermatitis
This includes Paget’s disease, eczema, Bowen’s disease and scabies.
Albright’s syndrome and Others
It will show irregular café au late spots and polyostotic fibrous dysplasia.
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| Albright's syndrome |
Henoch-Schoenlein disease may present with urticarial papules around the elbow plus the purpura on the buttocks and lower legs.
Consider syphilis if someone has pale ulcers in the mouth.
Hereditary haemorrhagic telangiectasia can look live caviar tongue. The latter is usually due to a lymphangioma.
The differential diagnosis of scrotal ulcers includes behcet’s, a fixed drug eruption and an artifactual lesion.
If you have papules in an area that otherwise looks like tinea it usually represents fungus in hair follicles.
If a patient appears to have erythematous patches on the face but it is only in the most cold exposed areas such as the ears and the lobes and the tips of the nose then consider leprosy.
This is seen in tuberous sclerosis, piebaldism, vitiligo, Voyt Koyanagi syndrome, Wardenbergs syndrome and neurofibromatosis.
The Phakomatoses
These are fibrous tumours involving the eye and the skin.
Café Au Late Spots
These are found in Albrights syndrome, neurofibromatosis, Blooms syndrome, Silver syndrome, Leprechaunism, tuberous sclerosis, Von Hippel-Lindau syndrome, ataxia telangiectasia, Leske’s syndrome, Sipples syndrome, Cowden’s syndrome and local morphoea. Note that the differential diagnosis of café au late spots and poliosis is either neurofibromatosis or tuberous sclerosis. The EEC syndrome is ectrodactyly giving a lobster claw deformity, peg teeth and a cleft palate. AEC syndrome is ankloblepharitis, peg teeth and a cleft palate.
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| Poliosis |
In Adenoma sebaceum angioid streaks do not go into the macular area. They do though in Pseudoxanthoma elasticum.
Naegeli’s syndrome is a reticulate pigmentation often in the neck and axilla. There is no preceding inflammation. There may be keratoderma of the palms and soles. The teeth may have a yellow discolouration of the enamel and they are mentally normal.
Fanconi’s syndrome is pigment like dyskeratosis congenita with some depigmented raindrop like macules. They have anaemia and thrombocytopenia, short hands and tapering fingers.
