Sunday, April 2, 2017

Rosacea steroid induced (Video)

We keep seeing this condition despite dermatologists repeatedly warning of the dangers of using a fluorinated steroid cream on the face for more than 7 days. This is steroid induced rosacea, in this case from mometasone but any fluorinated topical steroid can do it. There is overgrowth of a small mite called demodex in the skin which causes a generalised facial papular, sometimes pustular rash with curious sparing around the vermillion lip border. It really flares when the topical steroid is stopped but this has to be done to cure it. Also add in an oral tetracycline such as doxycycline 50 mgs bd and try some 2% sulfur in sorbolene cream bd topically. Within a week it will be improving but it often needs a month of therapy to see it settled completely without any scarring. The initial rash treated might have been seborrheic dermatitis but if it recurs then use any sulfur in sorbolene cream left! 1% hydrocortisone cream virtually never causes this condition.

Necrobiosis lipoidica (Video)

Rashes on the front of the shin are seen commonly with lichen simplex chronicus which is very itchy  and also with this condition, necrobiosis lipoidica diabeticorum (NLD). It is a condition you see in diabetics or pre diabetics. It is non scaling, not itchy and just slowly expands. The cause is not known but it is thought to be related to diabetes induced vascular damage. Although only about 22% of patients with NLD have diabetes those diabetics who also have NLD have an increased incidence of neuropathy, retinopathy and joint immobility. These lesions have recurred around a large plaque that had been treated with intralesional steroid injections into the inflamed edge. Most lesions have a raised edge and a central atrophic area where the underlying veins can be easily seen. Sometimes the underlying fat gives them a yellowish tinge. A punch biopsy of the edge should always be sutured as injuries here are very slow to heal. No other treatment has been shown to work in double blind trials.

Palmo plantar psoriasis (Video)

We are used to seeing patients with psoriasis present with large scaly plaques on the elbows, knees and lower legs but sometimes patients may only have psoriasis on the hands and feet and here the diagnosis is not quite so obvious. Overweight patients, who walk around barefoot or with open backed sandals, will often develop thick keratin build up on the heels where the keratin will dry and crack giving deep painful fissures. True psoriasis is usually more extensive as in this case with forefoot involvement and on the instep extending out on to the side of the foot. Fungal infection is always a differential diagnosis but in psoriasis the web spaces between the toes are spared. Patients should use closed in shoes and can try Daivobet ointment BD for a month but many patients require an oral retinoid such as Acitretin to peel away the scale first before using the calcipotriol steroid combination or narrow band UVB to prevent it recurring. 

Saturday, December 10, 2016

Lupus erythematosus Subacute

This looks a florid red non scaly rash. It could be many conditions including drug and viral exanthems. However the distribution of the rash helps narrow the diagnoses and suggest others. This rash was mainly on sun exposed areas, outer arms, V of the neck, lower legs below the dress line, sides of the face with sparing behind the ears. A photo distribution like this suggests a photo drug reaction particularly to thiazide diuretics or oral tetracyclines but also brings diseases such as lupus erythematosus into consideration. Discoid lupus is seen in sun exposed areas but is red and scaly. The red non scaly variants of lupus are either subacute or systemic. This patient had subacute lupus with positive ANAs and ENAs particularly the photo inducing Ro antibodies. A skin biopsy can help but the positive antibodies really make the diagnosis in the correct clinical setting. Treatment is sun protection with clothing and sunscreens, topical steroid creams and hydroxychloroquine until the rash settles. 

Male pattern alopecia

Early male pattern alopecia can be a major psychological problem to a young male. This 18 year old has early significant retraction of his anterior hair line and also had some occipital thinning. There was a family history of baldness but only in the grandparents. For this reason hormone studies were done including testosterone and dehydroepiandrosterone (DHEAS) in case of adrenal problems but these were all normal. He did not have hirsuitism elsewhere or bad acne and was not taking any gym steroid supplements.  Minoxidil topically or Finasteride orally will slow down the rate of hair loss in virtually all treated patients. However actual hair regrowth occurs in only 10% of  topical minoxidil and 20% of oral finasteride treated patients. The treatments are often combined. If hair regrowth occurs the treatments must be continued indefinitely or the regrown hair will fall out. Significant side effects are rare. Dutasteride is a new drug acting like finasteride but more effective and well tolerated.

Necrobiosis Lipoidica

Lesions on the anterior shin can be a skin cancer or psoriasis but if red non scaly with a raised edge then the likeliest diagnosis is necrobiosis lipoidica. This condition is most often seen in diabetics or pre diabetics where it starts as a small flat pink macule that gradually increases in size and develops a papular edge. The central epidermis may thin, allowing the underlying yellow of the fat to appear centrally with prominent veins. If this area is traumatised it ulcerates easily and is very slow to heal. For early lesions the best way to stop progression is to inject  Kenacort A10 diluted with 3 mls of local anaesthetic to 2.5 mgs per ml  into the lesion edge. This can be repeated after 4 weeks. Other measures are used to increase peripheral blood flow such as   Pentoxifylline or low dose aspirin and dipyridamole. Around 75% of patients who have necrobiosis lipoidica will ultimately develop diabetes mellitus. 

Saturday, August 13, 2016

Eczema Hyperpigmentation

Chronic eczema in a person with darker coloured skin always gives rise to marked post inflammatory hyperpigmentation. This lady has had a pompholyx like eczema for months with the chronic rubbing reflected in the skin thickening or lichenification shown here and the marked pigmentation. She should be investigated by patch testing for a possible contact allergy but can be managed initially with skin protection using cotton lined rubber gloves when washing and cleaning and cotton gloves inside plastic gloves when preparing foods where the juices of fish or meats or from potatoes and tomatoes can act as irritants and rarely be allergens. A strong steroid cream or ointment such as betamethasone dipropionate 0.05% should be applied twice daily to settle the eczema and the hands moisturised. A soap substitute should be used when washing. Once controlled the hyperpigmentation will gradually fade and the skin texture return to normal. Any allergen found on testing will have to be avoided. See for other images.

Zoon's balanitis

Red shiny plaques or patches on the genital skin usually bring the patient fairly quickly to the doctor. They can be seen in squamous cell carcinoma but are also a feature of psoriasis , lichen sclerosus, lichen planus and candida. Candida should cause a smell and slight discharge but the other diseases are difficult to tell apart without a biopsy. Psoriasis and candida will both respond to a cream containing hydrocortisone and clotrimazole twice daily for a couple of weeks but if there is no response a biopsy is necessary. Sometimes the biopsy is reported as a Zoon’s balanitis. This is a curious reaction pattern in genital skin where the skin is infiltrated with lots of plasma cells in the dermis. It may be secondary to infection such as candida or chronic irritation and respond to the steroid clotrimazole mixture or a slightly stronger steroid cream. Persistent red plaques should always be biopsied to exclude a squamous cell carcinoma in situ. 

Crusted Scabies

This is the first of several articles where things are not quite what they seem to be. This looks like it is a red scaly rash. You might consider psoriasis, eczema or perhaps a fungal infection as a cause of all this scale. This patient had a past history of severe atopic eczema and had regularly been treated with oral antibiotics and courses of oral steroids. However every time her steroids were reduced the rash would flare and her itch would become intolerable. The scale would persist. The diagnosis was made by asking her partner, who came with her, if anyone else at home was itchy?  He immediately volunteered that he also had an itchy rash which on examination showed typical scabies burrows in the web spaces, wrists and genitals. His partner had the rare variant crusted or Norwegian scabies. Luckily there was no one else at home to become infected because crusted scabies easily starts scabies epidemics. The patient was treated with a single dose of Ivermectin repeated in a week with daily applications of permethrin cream all over in between.

Lichen Planus

This is a skin graft site on the thigh. A rash has arisen within the graft site. That rash is itchy and has a violaceous colour. The condition is lichen planus.  The patient had this graft taken to place on a lump on the leg that was excised. It had previously been biopsied and reported as an  inflamed well differentiated squamous cell carcinoma. A new rash is also now appearing in the centre of the grafted  excision site on the shin. Is this a recurrence of the excised SCC? No it also is lichen planus. The problem is the initial lesion reported as a well differentiated SCC  was actually hypertrophic lichen planus! The lump would have responded to intralesional steroid injections and the surrounding rash to a strong topical steroid under occlusion. Mistaking hypertrophic lichen planus for a well differentiated SCC is a well recognised error in dermatopathology. Just to complicate things rarely an SCC can arise in very long standing poorly treated lichen planus! Whoever said “Life was not meant to be easy”, was probably thinking of dermatopathologists.