Sunday, February 22, 2015
Only those aspects of treatment which differ from routine practice or are related specifically to dermatology are described.
Washing-Routine washing with soap and water may do much harm or much good, depending on the particular disorder being treated. specific instructions must, therefore be given in every case. In eczematoug and exudative eruptions as a whole washing should be reduced to a minimum. Soap and water also usually aggravates seborrhoeic dermatitis, rosacea, and. pityriasis rosea. on the other hand frequent washing forms an integral part of the treatment of acne vulgarif and daily tar baths are prescribed for psoriasis. In all other conditions no changes need be made.
Diet- Dietetic treatment is tittle used in dermatology' occasionally some food, substance may be the cause of urti-caria and must therefore be eliminated. on the other hand, food and. drink play no part in either infantile eczemlu or any other eczematous Lruption. It is traditional to restrict the intake of carbohydrates in seborrhoeic dermatitis and chocolate in acne vulgaris, though usually little discernible improvement results. Any food or drink which normally tends to cause flushing, such as hot tea, spiced food or alcohol, will temporarily aggravate rosacea, but has no permanent effect. A reducing diet is probabty the most, useful dietetic weapon as many dermatological patients are over-weight and this materiaily aggravates their maladies. Finally a particular type of low fat diet may be used in the treatment of xantha- matosis
DRUGS-Systemic treatment is playing a larger and larger part in dermatology. specific drugs used in the treatment of individual diseases are described in the section dealing with those diseases. The following remarks concern the particular use in dermatology of drugs common to the whole of medicine.
Antipruritics- There is, unfortunately, no drug which has a specific effect on itching. some decrease of this symptom can hover be obtained by the judicious use of sedatives and antihistamines.
Sedatives-These are extensively used to reduce tension, to relieve itching and to obtain sleep. Small doses, such as phenobarbitone, mg. 16 to 30 (gr.1/4 to 1/2) or amytal mg. 50 (gr. 3/4), may be given two or three times through the day and larger doses may be given at night. If itching is severe, very large doses at night often only decrease the patient's ability to refrain from scratching, without inducing sleep. Tranquillisers have on the whole proved disappointing, although .hlotoptomazine (Largactil) and chlordiaziepoxide (Librium) are sometimes helpful, as are some of the newer phenothiazine derivatives.
Antihistamines do not prevent the liberation of histamine but, as the name indicates, inhibit its action. They also have a mild antipruritic effect which is quite separate from their antihistaminic action and which therefore can be utilised in other conditions. The different, compounds in this group vary in their length of action and in the intensity of their sedative effect. chlorpheniramine maleate (Piriton), cyproheptadine hydrochloride (Periactin) and triprolidine hydrochloride (Actidil) for instance are effective for about 4 hours and have a moderate sedative effect, which tends, as is the case with all members of this group of drugs, to become less marked the longer the substance is given. on the other hand, promethazine (Phenergan) exerts its effect for about 12 hours and, because it also has a marked. hypnotic effect, is best given last thing at night. The majority of these compounds are also available in the form of an elixir for the treatment of children and as injections for intramuscular or intravenous use. There are a great number of antihistamine drugs available and new ones are constantly being produced. Efrorts are now being concentrated on their antipruritic properties and trimeprazine, which is given in doses of l0 mg. three or four times a day, is one of the first marketed for this purpose. It has a definite, though unfortunately only slight, effect on itching. None of these substances have any antihistaminic effects when apptied locally, although they are markedly antipruritic when used in this way. Nevertheless, they should never be employed topically because of their sensitizing properties and the consequent risk of causing dermatitis.
Bacterial. systemic antibiotics are less frequently required in dermatology than in other branches of medicine,since it is possible to control most, infections by local applications. when systemic therapy is necessary, penicillin remains the first choice, since the staphylococcus is by far the commonest infecting organism, being present in pure culture in over 60% of all infective conditions and in mixed culture in over 90%. The increasing number of resistant strains must however be borne in mind and these occur in about staphylococci, cloxacillin, areg enerally effective and it is rarely necessary to use chloramphenicol or any of the erythromycin group. The long-term use of penicillin in recurrent erysipelas and tetracycline in acnev ulgaris is dealt with in the sections dealing with those diseases. In choosing a loeal antibiotic three things must be borne in mind, the sensitivity of the organism, the potency of the antibiotic and its irritant effect on the skin. Thus penicillin and streptomycin are never used locally, since they so frequently cause a sensitisationre action. Bacitracin and tyrothrycin are relatively weak antibiotics and of little use when used alone. The tetracyclines and erythromycins should not be used topically unless they are specifically indicated since, becauset hey are needed to combat serious systemic infections, every effort must be made to avoid increasing resistant strains of organism by unrlecessary use. This does not apply nearly so forcibly to chloramphenicol, but here the chanceso f causing a sensitisation dermatitis are greater than with the latter groups of antibiotics, but much less than with penicillin or streptomycin. The antibiotics of choice for external use are those which are never used systemically, namely neomycin, soframycin and polymyxin. The first two are available as ointments or lotions and control the great majority of infective conditions. If they fail and adequate bacteriological investigation is unavailable a change should be made to chloramphenicol, especially as it is effective against most of the gram-negative organisms. Polymyxin, although very effective against staphylococci, should be exclusively reservedf or the treatment of infections due to pseudomonas pyocyanea. It is available as an ointment (Polyfax) and as a lotion (Otosporin).
Fungal. Nystatin, an artibiotie isolated from a strepto-myces, has a specific action against caniliila albieans (monilia). It may be prescribed in the form of an ointment, suspension, or ear drops (dissolved in propylene glycol), in a strength of 100,000international units per gram or millilitre, and as tablets (500,000 units per tablet) for oral use. The latter are not absorbed and only exert, their effects against candida in the gut. Amphoterecin B, obtained from streptomyces nodosus, is also effective against candida. It is used either locally or as a slow intravenous injection for systemic cases.
Monday, January 5, 2015
Diagnosis is not usually difficult. Gummatous ulcers and Bazin's disease, are the most likely conditions to cause difficulty. The presence of varicose veins, oedema, purple discolouration, pigmentation and thickening of the skin,
ulceration on the inner side of the lower third of the leg and extreme chronicity are in favour of varicose ulcer. Syphilitic ulcers may occur in patients who already have varicose dermatitis, but they are likely to be on the outer side of the leg, to begin as swellings which break down in the centre, to have a " punched out" appearance, a yellow sloughy base and to be arranged in arcs of circles. The Wassermann reaction will probably be positive but a patient with a varicose ulcer may also have syphilis and so give a positive Wassermann.
Local-varicose eczema is treated in the same way as other eczematous eruptions,the condition responding well under compression bandaging. varicose panniculitis requires no local application, but responds well to surgery, compression or both. When the condition is painful, however, an initial period in bed may be necessary. Varicose ulcers should be treated locally with bland applications, such as wet gauze compresses of half strength Eusol or equal parts of Eusol and liquid paraffin.Occasionally, when secondary infection is severe, especially if with Ps. pyocyanea, the appropriate antibiotic may be applied. Complete occlusion for a week at a time with an occlusive bandage such as Viscopaste is sometimes the best treatment. Large or painful ulcers may necessitate a short period in bed. Occasionally, skin grafting is required.
A very common condition in middleaged women and elderly men with varicose veins. The skin on the lower third or half of the inner side of one or both legs has usually been for a long time congested and purplish or else pigmented with blood pigment and
scaly. Then it becomes irritable, develops vesicles and becomes eczematous. This form of eczema is usually on the inner side but may be on the outer side of the leg depending on which veins are varicose. The condition is very chronic and after it has been present for some months general sensitisation of the skin to products of pidermal break-down takes place so that if the patient then scratches his 1eg vigorously, or applies an irritating ointment, he is very likely to wake up in the morning with eczema also on his face, neck, arms or hands. Varicose eczema may also arise in the skin overlying a varicose vein in any part of the lower limb.
PERNIOSIS SKIN DISEASES
Lesions which may be mistaken for chilblains are papulo-necrotic tuberculides , lupus erythematosus and nodular vasculitis . The former are smaller and more regular in size than chilblains, they occur also on the elbows, shoulders, and legs, and leave small white depressed scars. Ordinarily chilblains leave no scars, but it they become ulcerated they leave irregular scars. Papulo-necrotic tuberculides are apt to occur in people who have acrocyanosis and possibly actual chilblains as well. Lupus erythematosus when it occurs on the hands forms oval plaques or rings on the backs of the fingers; these are bluish-red and may be scaly, or may show the characteristic stippling. other lesions of lupus erythematosus will most likely be present also on the face. Nodular vasculitis causes more inflammatory lesions, does not ulcerate, lacks the background of cold, blue calves and occurs in older women.
Warm clothing is essential, and this applies as much to the trunk as to the extremities. on the whole, vasodilator drugs have proved disappointing, but some improvement may be obtained from tolazoline hydrochloride 25-50 mg. thrice daily, dibenylene 10-20 mg. thrice daily or bamethan sulphate (Vasculit) 12.5 mg. four times a day. The latter is probably the most effective, but the side-effects may be troublesome. Severe chilblains can be incapacitating and then sympathectomy may be indicated.
Sunday, January 4, 2015
ERYTHEMA NODOSUM SKIN DISEASES
From Bazin`s disease. This is a chronic disease and affects the lower halves of the backs of the legs. It tends to recur every winter. The nodules are purple, relatively painless, and often ulcerate. These distinguishing features also apply to nodular vasculitis, except that the lesions occur at any time of the year and are red rather than purple. From erythema multiforme. In this the lesions are likely to be most, marked on the hands or arms and to be maculo-papular or vesicular. They are not painful or tender, and there is seldom much fever. Prognosis. The disease usually lasts about three weeks and the lesions leave no scars. It seldom recurs.
Every effort should be made to discover the cause, which should then be treated. further, a follow-up of at least, a, year should he instituted, including twice yearly chest X-rays. During the acute phase, the patient, should be put to bed and treated with aspirin or salicylates.
Locally, calamine or lead, lotion is soothing.
Vesicular and Bullous type skin diseases
Erythema multiforme is not as a rule difficult to diagnose, but the vesicular and bullous type may have to be distinguished from pemphigoid. Erythema multiforme occurs in a much younger age group and is a more obviously centrifugal disease, affecting the hands and feet, elbows, knees and neck. Cases with small vesicles may cause confusion with dermatitis herpetiformis. In the latter disease the eruption tends to be less symmetrical, has less tendency to be limited to the extremities, irritates much more, and is often accompanied by an eosinophilia. Cases with the eruption chiefly on the face may be confused with lupus erythematosus . In this disease, however, the nose and ears are often affected and the follicles on the affected part are filled with little horny plugs which give the skin a stippled appearance. Lupus erythematosus usually follows a, very chronie course while erythema multiforme is essentially an acute disease.
Prognosis. The eruption will probably disappear in two to three weeks leaving no scars, but it is very liable to recur.
Every effort should be made by means of a careful history and thorough general examination to find a cause and this should then be treated. Little else can be done and no drug has any specific effect in the condition. When the mucous membranes are involved, especially those in the eye, local or systemic antibiotics may be needed to control secondary infection. Steroid hormones given systematically appear to be helpful in certain of the severe bullous and mucosal cases.