Topics discussed in this Tutorial
Leukemia
Atypical Fibroxanthoma
Nodules and arthritis
Plaques
Leukoplakia
Separating Leprosy from Morphoea
Histiocytoses
Generalised hyperpigmentation
Dagos disease
Unusual types of Herpes simplex
Blue legs and Ulcers DD
Red spot disease
Light eruptions in children
Causes of Pseudotumours
Leukemia
There are generally no specific skin lesions in acute leukemia.
The specific skin lesions in chronic lymphatic leukemia are nodules, erythroderma or diffuse infiltration sometimes giving rise to leonine faces. In granulocytic leukemia the skin lesions are uncommon but there is a chloroma, which is a greenish tumour in children due to myeloperoxidase. Monocytic leukemia can give an acute exanthem like rash, which goes bluish later, you can have purpura on the legs, you can have ulcerating papules on the legs and you can have some infiltration of the gums. Image in GSA
Non-specific skin findings in leukemia are polymorphous with very many lesions. Pruritus is the most common in chronic lymphatic leukemia. Prurigo can also occur. Haemorrhage, erythroderma, herpes zoster particularly in chronic lymphatic leukemia though it can become generalised and haemorrhagic with large bullae in the mouth.
If monocytic it is mainly the skin that is involved. If lymphatic it is mainly pruritus and if they have got varicose veins then hyperviscosity can give rise to ulcers. With a plasmacytoma this can present as amyloid or primary systemic amyloidosis.
This cutaneous infiltrate was seen in chronic lymphatic leukemia
Atypical Fibroxanthoma
It should have been put in as part of the differential diagnosis of pyogenic granuloma. You often have bizarre spindle shape cells and atypical histiocytes. The lesions present on the ears of elderly patients, are reddish brown and often ulcerate and crust just like a BCC or some SCCs.
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| Atypical Fibroxanthoma ear |
Nodules and Arthritis
If you are asked to examine a case of a patient with nodules and arthritis consider rheumatoid arthritis, gout, lupus, sarcoid, Sweet’s and erythema elevatum diutinum. Image in GSA From the sarcoid point of view always check the eyes and the parotid glands.
The image is of an atypical fibroxanthoma
Plaques
If a patient presents with large non scaly plaques consider chronic infection, particularly granulomatous disorders such as TB, Leprosy and Deep fungi and Other Atypical Mycobacteria , vasculitis, malignancy particularly lymphomas and infiltrations with cells and substances particularly leukemia, and the mucinoses.
Leukoplakia
Leukoplakia is commonly seen on the lips and the inside of the mouth and tongue. Most cases are benign hyperplasias but some are premalignant secondary to cigarette smoking or papilloma virus. Note that syphilis can give an atrophic mucositis with leukoplakia and there is a condition called smokers leukoplakia with umbilicated lesions on the roof of the mouth. GSA on Leukoplakia Also see these other images with lichen planus as a differential
The image is of oral leukoplakia in the floor of the mouth and undersurface of the tongue.
How can you separate a suspected case of leprosy from morphea?
Remember that morphea can be hypo anaesthetic. There can be little sweating and it can have an insidious onset as well. The skin will be more indurated in morphoea than leprosy.
Answer
You look for the thick nerves associated with leprosy. Distinguishing between leprosy (Hansen’s disease) and morphea relies on three main differences: sensory loss (leprosy), skin texture firm bound down (morphea), and nerve involvement (leprosy)
Alopecia mucinosa can be another differential because there is reduced sensitivity to cold in these lesions and some of the lesions are hypopigmented as well.
The Histiocytoses
These are rare disorders. I have only seen, I think, one florid case in Specialist practice in an old lady who presented with lesions in areas looking like Darier’s. Hand Schuller Christian disease can present with diabetes insipidus. About a third get pulmonary metastases. It also starts as seborrhoeic dermatitis and may present with bone cysts on the skull. Multiple xanthomas may also be seen. Eosinophilic granuloma usually starts about the orifices or genitals with greasy scaly papules associated with easy bleeding or petechiae in the skin.. It does involve bone but it has a better prognosis. GSA on Langerhans cell histiocytosis
The image is a case of tuberculoid leprosy
Generalised Hyperpigmentation
The mnemonic is DAMNE PIG. Burnt out Scleroderma is the commonest collagen disease causing hyperpigmentation.
D-Drugs Melasma, Fixed drug eruption,bleomycin,arsenic,gold and cyclophosphamide,Puva
A Autoimmune Scleroderma,lupus erythematosus and dermatomyositis
M-Metabolic Addison’s disease,Porphyria cutanea tarda,Hemochromatosis,Renal and hepatic failure,Amyloidosis
N-Nutritional Pellagra,Malabsorption
E-Endocrine Hyperthyroidism,Pregnancy,Cushings,Acromegally,Thyrotoxicosis,Pheochromocytoma
P-Physical Post sunburn,Post taumatic,Racial pigmentary demarcation lines,Phototoxic hyperpigmentation (Plants),Vagabond’s disease
Dagos Disease
This occurs in crops, probably a form of vasculitis. The patient may have abdominal pain due to perforation. There may be 30 or more active lesions at any one time. Image Differentials include the chronic form of pityriasis lichenoides, albo papuloid epidermolysis bullosa and syphilis. Some people consider Degos a variant of Lupus erythematosus.
There are usually no long lasting scars from pityriasis lichenoides chronica.
This is the pigmentation seen in scleroderma. Commonly called salt and pepper pigmentation.
Answer
Those occurring primarily in the mouth or on the fingertip or secondary to wrestling, particularly on the chest and the face and ezema herpeticum where generalised herpes simplex affects someone suffering atopic dermatitis but there are other diseases in which this can occur. Do you know what they are? ( Dariers, PRP, for starters) In secondary herpes virus infections lymphadenopathy is common without any secondary bacterial infection.
The image below is of a severe primary herpes simplex infection in an infant
A patient presents with blue legs and ulcers. What conditions do you think of?
Answer
Nodular erythrocyanosis, erythema nodosum, nodular vasculitis, erythema induratum, sub-acute migratory nodular panniculitis which is usually preceded by infection or trauma, thrombophlebitis migrans which can be secondary to malignancy elsewhere or Bazins disease. See Dermnet on Panniculitis
You can also get livedo with nodules, patients are usually female with some pain but no ulceration and polyarteritis nodosa will present with blue legs and ulcers often with nodules and vasculitis. Calciphylaxis is another condition with levido and ulcers.
The image below is of erythema nodosum
Causes are embolic, local inflammation or bites. Embolic can be due to viruses, bacteria or drugs. Viruses will generally show cropping of lesions. Drugs seldom do. If bacterial syphilis is often the commonest although sub-acute bacterial endocarditis may do the same. Local inflammatory causes include folliculitis or involvement of sweat glands and bites are usually due to insects.
Red Spot disease is not really a useful term as the range of disorders is immense. I think of it most with Rickettsial infections in children and adults with fever . The initial tick bite might leave an eschar with the red macules developing acrally on palms and soles sometimes with petechiae. See Dermnet
Tinea cruris may arise in the pubic area whereas erythrasma seldom appears there. It particularly occurs in flexures.
The red spot disease below was caused by leech bites
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| Severe papular urticaria from bed bug bites |
Answer
Juvenile spring eruption typically occurs in boys on the ears and may blister. Hutchison’s summer prurigo is non-scarring and often in non-sun exposed areas. Hydroa vacciniforme causes crops and it causes scarring and is mainly on the face. Polymorphous light eruption can present as eczema papules with an onset 8 to 12 hours after exposure and may even be later.
The image below is hydroa vacciniforme
Acrodermatitis Chronica Atrophicans
May present as pseudo tumours occurring on the elbows.
Question
What are the causes of pseudo tumours?
Answer
Goltz syndrome, acrodermatitis chronica atrophicans, Ehlers Danlos syndrome and anetoderma. All these pseudo tumours are soft with herniation. There is either loss of the dermis in Goltz syndrome or loss of elastic tissue as in anetoderma.
What are the clinical features?
Answer
Basically they have hyperextensible skin which will spring back as against cutis laxa which takes much longer. They have some fragility of the skin and scarring may well occur over the joints. There is joint hyperelasticity, blue sclerae and pea size nodules on the shins and the forearms. Image in GSA
What other diseases may be associated with Ehlers Danlos syndrome?
The image below is of acrodermatitis chronica atrophicans.
