What Is Acne?
Acne are skin lesions usually limited to the face, shoulders, upper chest and back. The lesions comprises of inflammatory papules, nodules and cysts; representing various stages of progression of the skin condition. In most individuals, one or two types of the lesions predominate (either papules and nodules, or nodules and cysts or papules and cysts). Invariably, scarring follows after a while.
What Are The Various Types Seen In Most Individuals? (i.e. Clinical Variants):
(a) Conglomerate Acne: This refers to severe acne with many abscesses and cysts, resulting in marked scarring of the skin and sinus formation.
(b) Acne Fulminans: Refers to severe acne accompanied by fever, joint pains and systemic inflammation generally.
(c) Acne Excoriee: Refers to the effects of scratching or picking, principally on the face of teenage girls (and boys at times) with acne.
(d) Infantile Acne: This is rare and is thought to be due to the sebotropic effects of maternal hormones on the infant.
(e) Acne Due to Exogenous Substances: This refers to a mild form of acne dominated by the presence of comedones (blackheads or whiteheads). Blackheads are open comedones occurring due to plugging by keratin and sebum of the pilosebaceous orifice of the skin while Whiteheads are closed comedones occurring due to accretions of sebum and keratin deeper in the pilosebaceous ducts. These occur due to contacts with such exogenous substances as: Tars, Chlorinated Hydrocarbons, or Oily Cosmetics. A similar pustular rash may also be seen in those being treated with Corticosteroids, Lithium, Oral Contraceptives and Anticonvulsants. These form of acne are usually clinically distinct from the varieties listed above which usually develop in adolescence.
The common name for acne described in(a)(b)(c) & (e) is ACNE VULGARIS.
What Causes It? (Aetiology):
Three main pathogenic factors have been identified, and they are:-
(1) Elevated Sebum Excretion: A clear relation has been established between the severity of acne and sebum excretion rate. It is to be noted that in the complete absence of sebum, acne does not occur. However, the converse of this statement is not true, for acne has been known to improve in the third and fourth decades of life despite high sebum excretion. The main determinants of sebum excretion are hormonal, accounting for the onset of acne in the teenage years. Androgens and progestogens increase sebum excretion although androgens are the principal sebotropic hormones, while estrogens reduce it. It is to be said, however, that the vast majority of patients with acne have a completely normal circulating endocrine profile.
(2) The second factor is infection with Propionibacterium acnes: This bacterium colonises the pilosebaceuos ducts and acts on lipids to produce a number of pro-inflammatory factors.
(3) The third factor is occlusion or blockage of the pilosebaceous unit.
• There is some evidence for a familial component for sebum excretion but the genetics and epidemiology of this with regards to acne has been little studied so far.
How Does One Get It?:
In most cases acne develops on its own in most individuals during the teenage years as the hormonal changes begin to take place in the body. However, theoretically speaking coming in contact with the bacterium Propionibacterium acne on the skin of a person with fulminant acne may predispose to one developing it, but this is rarely the case.
How Can One Get Rid Of It? (Treatment):
For individuals with fairly minor manifestations, particularly those dominated by the presence of comedones (blackheads & whiteheads) topical agents such as Benzoyl Peroxide or Tretinoin should be used. Patients with severe acne require treatment with Antibiotics both local and systemic. Local antibiotics (Clindamycin or Erythromycin) are applied to the lesions, at times in combinations with other topical agents like Benzoyl peroxide. The principal oral systemic antibiotic is Oxytetracycline, usually taken on an empty stomach to ensure maximal absorption. Up to 1.5g a day in divided doses can be given if tolerated.
Minocycline may be used if oxytetracycline is not tolerated although this is associated with autoimmune hepatitis and has to be used with caution. It remains a second rather than first drug of choice.
These antibiotics need to be taken for at least 3 months to be able to fully access their curative effect. If after 3 months there is little response to oxytetracycline the patient should be changed to Erythromycin 1g daily in divided doses. In women, oestrogen containing oral contraceptives can be a useful adjunct in therapy. Oestrogens help reduce sebum secretion. Cyprotene acetate (an oral anti-oestrogen) is occasionally added in doses of 50 - 100mg daily in days 5 -14 of the cycle to enhance the effects of sebum reduction. Should these topical and systemic agents fail to produce an appreciable clinical response within 3 - 6 months, then the patient should be referred for a specialist (Dermatological) opinion and consideration for treatment with Isotretinoin ( 13 Cis-Retinoic Acid) taken.
Isotretinoin has revolutionized treatment of severe to moderate acne in patients unresponsive to other therapy. At a dose of 0.5 - 1mg/kg body weight, this drug inhibits sebum excretion by greater than 90% over 4 months. Although sebum excretion gradually returns to normal over the course of a year after the drug is stopped, the clinical benefits are prolonged for much longer. In most cases, patients do not require any further treatment but in a minority, a second course may be required.
Side Effects Of Isotretinoin: --Drying of skin and mucous membranes are common but well tolerated. This relates to the drug's effects on the function of modified sebaceous glands on the lips, and on lipid biosynthesis in interfollicular epidermis.
--Rarely abnormalities of liver function occur and limit treatment.
--Isotretinoin may elevate serum triglycerides. Levels should be checked before treatment and monitored during and after.
--Depression and suicide have been reported, although it is difficult to disentangle the role of the drug from that of the underlying disease and the age groups at risk. Further studies and research are being carried out in this area.
N.B. The major consideration before the drug is prescribed is that like all systemic Retinoids, Isotretinoin is highly Teratogenic. Females must have a negative pregnancy test before treatment is commenced and must have monthly checks during treatment and must be on effective contraception 1 month before treatment begins and 1 month after it finishes.
Some Physical Aspects Of Treatment: Incision and drainage of cysts can be done under local anesthetic, while intralesional injections of Triamcinolone acetonide (0.1 - 0.2mls of a 10mg/ml solution) helps to hasten resolution of stubborn cysts. Adequate care of lesions results in less scarring. Small and deep acne scars can be excised and other forms of more extensive but shallower scars can be treated by Carbon dioxide Laser by the specialist.
Acne Rosacea:
This is a persistent facial eruption of unknown cause, characterized by Erythema and Pustules. Sebum secretion is normal. The disorder is most common in middle age and involves the cheeks, chin and central forehead in most cases. Dome shaped Papules and Pustules but no comedones occur. Rhinophyma, with erythema, sebaceous gland Hyperplasia and overgrowth of the soft tissue of the nose sometimes occur in association. Blepharitis and Conjunctivitis are complications.
Treatment:
This involves oral oxytetracycline mostly on a long term basis. Once it is under control the oxytetracycline dose can be reduced but some individuals need to stay on the antibiotic long term or may require repeated courses. Topical Metronidazole (Flagyl) also shows some efficacy in curing the papules and pustules, although it may cause irritation in some individuals.
N.B.: These treatment regimens for Acne Vulgaris and Rosacea under normal circumstances cannot be carried out by individuals since the drugs involved are mostly prescription drugs that can only be obtained through the Physician, these treatments have been written to educate and inform those suffering from Acne, so that when they see their physician, they are better able to grasp his or her explanations and understand the line of management of their condition.
A Glossary Of Medical Terms Used In This Article:-
Abscess: A localized collection of pus in a cavity formed by the disintegration of tissues.
Antibiotic: A chemical substance produced by microorganisms, which has the capacity, in dilute solutions to inhibit the growth of or to destroy bacteria and other microorganisms: used largely in the treatment of infectious diseases of man, animals and plants.
Bacterium: small minute germ visible only under the microscope (plural=bacteria).
Blepharitis: Inflammation of the eyelids.
Conjunctivitis: Inflammation of the delicate membrane that lines the eyelids and covers the exposed surface of the eyeball (Conjunctiva).
Comedone: A plug of dried sebum in an excretory duct of the skin.
Cyst: Any sac, normal or abnormal, containing a liquid or semisolid material.
Dermatology: Branch of medicine concerned with the diagnosis and treatment of diseases of the skin.
Erythema: Redness of the skin produced by congestion of the capillaries which may result from a variety of causes.
Epidermis: The outermost and nonvascular layer of the skin made up of five layers.
Hyperplasia: The abnormal multiplication or increase in the number of normal cells in normal arrangement in a tissue.
Inflammation: The condition into which tissue enter as a reaction to injury. The classical signs of inflammation are: - pain (dolor), heat (calor), redness (rubor), and swelling (tumor); to which may be added at times the loss of function (function laesa).
Lesion: Any pathological or traumatic discontinuity of tissue or loss of function of a part.
Nodule: A small solid swelling or protuberance which can be detected by touch.
Papule: A small circumscribed, solid elevation of the skin.
Pustule: A small elevation of the skin filled with pus.
Pilosebaceous: Sebaceous gland associated with the hair follicle.
Rhinophyma: A form of rosacea characterized by nodular swelling and congestion of the nose.
Sinus: An abnormal channel or tract permitting the escape of pus.
Sebum: Secretion of the sebaceous glands; a thick, semifluid substance composed of fat and epithelial debris from the cells of the inner layer of the skin (Malpighian layer).
Teratogenic: Tending to produce anomalies of formation especially in multiplying cells.
Author: Ola Suyee PS: Comments and Questions are welcome, Thanks, Suyee.
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