"INTERNAL MEDICINE"

WANT TO KNOW ABOUT YOUR ACNE VULGARIS ?

Acne is almost ubiquitous in the teenage years, differences between individuals being a matter of severity of disease and facility with which scarring develops. Peak severity is in the late teenage years but acne may persist into the third decade and beyond, particularly in females. The main clinical issues relate to under-treatment and lack of clinical interest or insight into the patient's condition.

HOW IT HAPPENS?
There are three pathogenetic factors
• The first is elevated sebum excretion. There is a clear relation between severity of acne and sebum excretion rate. In the complete absence of sebum, acne does not occur. The converse, however, is not true; acne may improve in the third and fourth decades despite high sebum excretion. Sebum excretion is therefore necessary for the development of acne but is not sufficient to cause acne on its own. The main determinants of sebum excretion are hormonal, accounting for the onset of acne in the teenage years. Androgens are the principal sebotrophic hormones but progestogens also increase sebum excretion whilst oestrogens reduce it. In the absence of other suggestive clinical features or frank virilism the vast majority of patients with acne have a completely normal circulating endocrine profile.
• The second factor in the pathogenesis of acne is infection with Propionibacterium acnes. This bacterium colonises the pilosebaceous ducts and acts on lipids to produce a number of pro-inflammatory factors.
• The third factor is occlusion or blockage of the pilosebaceous unit.
Whilst there is some evidence for a familial component for sebum excretion the genetics and epidemiology of acne have been little studied.



HOW IT PRESENTS?

1.Lesions are usually limited to the face, shoulders, upper chest and back. Seborrhoea (greasy skin) is often clinically obvious.

2.Open comedones (blackheads) due to plugging by keratin and sebum of the pilosebaceous orifice, or closed comedones (whiteheads) due to accretions of sebum and keratin deeper in the pilosebaceous ducts, are usually evident.

3.Inflammatory papules, nodules and cysts occur with one or two types of lesion predominating. Scarring may follow.
SOME TERMS

1.Conglobate acne refers to severe acne with many abscesses and cysts, marked scarring and sinus formation.
2.Acne fulminans refers to the presence of severe acne accompanied by fever, joint pains and markers of systemic inflammation such as a raised ESR.
3.Acne excoriée refers to the effects of scratching or picking, principally on the face of teenage girls with acne.
4.Infantile acne is rare and is thought to be due to the sebotrophic effects of maternal hormones on the infant.









WHAT ARE THE ASSOCIATIONS?

1.A mild form of acne dominated by the presence of comedones may be due to exogenous substances such as tars, chlorinated hydrocarbons or oily cosmetics.
2.A primarily pustular rash may also be seen in those being treated with corticosteroids, lithium, oral contraceptives and anticonvulsants. These forms of acne are usually clinically distinct from the usual variety developing in adolescence.


3.Individuals with moderate or even severe acne very rarely have any other systemic disorder.

4.Individuals with polycystic ovary syndrome are more likely to have severe acne, and clinical hints-for instance, menstrual irregularities-require investigation. If there is associated cutaneous virilism or other features of an androgen-secreting tumour, further investigations and expert endocrinological assessment are warranted.

DO YOU NEED INVESTIGATIONS?

Investigations are rarely required. It is important, however, to enquire about the details of previous treatments and particularly about their duration; for example, antibiotics are commonly prescribed for too short a period of time.

WHAT IS THE TREATMENT?

1.The advent of systemic retinoids revolutionised the therapy of acne, which is now more straightforward and rewarding. In individuals with fairly minor disease, particularly dominated by the presence of comedones, topical agents such as benzoyl peroxide or tretinoin should be used. Both these substances have irritant activities, a factor which may be important in their therapeutic effect, and instructions should be given on how to use them. They may initially be applied for short intervals of time and the strength and duration gradually increased.

2.Although a number of other topical remedies, including washes, soaps and antiseptics, are recommended, evidence for their effectiveness is not convincing.

3.Patients with anything but minor degrees of acne require therapy with antibiotics, either systemic or local. Local antibiotics (clindamycin or erythromycin) are used more widely than previously; their use should be considered prior to systemic antibiotics or in persons with relatively minor disease, and in combination with other topical agents.
The principal oral antibiotic is oxytetracycline, taken on an empty stomach not with food, in a dose of up to 1.5 g a day if tolerated. In general, oxytetracycline has a good safety profile even with long-term use. Minocycline may be used if the response to oxytetracycline is inadequate or because of the ease of dosing. It is, however, associated with autoimmune hepatitis and remains a second- rather than first-choice drug.
Before an antibiotic is deemed not to have worked, the individual must be treated continuously for up to 3 months. If after 3 months there is little response to oxytetracycline the patient should be changed to erythromycin up to 1 g per day in divided doses. Patients need to remain under review.

4. In women, oestrogen-containing oral contraceptives can be a useful adjunct in therapy. There is a small reduction in sebum secretion with oral oestrogens. An oral anti-oestrogen, cyproterone acetate, is occasionally added in doses of 50-100 mg daily on days 5-14 of the cycle to enhance the effects of sebum reduction. If these topical and systemic agents fail to produce an adequate clinical response within 3-6 months the patient should be referred for specialist opinion and consideration for treatment with isotretinoin

5.Isotretinoin has revolutionised the treatment of severe or moderate acne in patients unresponsive to other therapy. When used at a dose of 0.5-1 mg/kg this drug inhibits sebum excretion by > 90% over 4 months. Although sebum excretion gradually returns to normal over the course of the year after the drug is stopped, the clinical benefit is prolonged for much longer. Many patients with acne will not require any further treatment but in a minority a second course of isotretinoin may be required.

6.Side-effects, especially drying of the skin and mucous membranes, are common but well tolerated and relate 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 therapy and monitored during it. Depression and suicide have been reported, although it is difficult to disentangle the role of the drug from that of the underlying disease and age groups at risk; it is currently under investigation. 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 and monthly checks, and must be on effective contraception for at least 1 month before the course begins, during the course and for 1 month after it finishes.

7.Physical measures :
Cysts can be incised and drained under local anaesthetic. Intralesional injections of triamcinolone acetonide (0.1-0.2 ml of a 10 mg/ml solution) hasten the resolution of stubborn cysts. Scarring following acne is seen a lot less commonly if patients receive adequate care. Small, deep acne scars can be excised and other forms of more extensive but shallower scars can be treated by carbon dioxide laser.



THINGS YOU MUST KNOW?


External factors
1.Cosmetics may contribute to the development of acne. Oils, greases, or dyes in hair products and cosmetic creams can exacerbate the skin lesions, while water-based products are less comedogenic

2.Soaps, detergents, and astringents remove sebum from the skin surface but do not alter sebum production. Repetitive mechanical trauma caused by scrubbing with these agents may worsen the disorder by promoting the development of inflammatory lesions . Similarly, turtlenecks, bra straps, shoulder pads, orthopedic casts, and sports helmets may all cause acne mechanica. Thus, patients with acne should avoid occlusive clothing and refrain from rubbing their faces or picking their skin.

3.Environmental factors such as humidity and heavy sweating also can exacerbate acne. Chloracne is caused by exposure to halogenated hydrocarbons, including dioxin, via percutaneous contact, inhalation, or ingestion. These chemicals are found in industrial products such as cutting oils and herbicides, in chemical warfare, and in contaminated food products. Clinically, chloracne is characterized by large monomorphic comedones with evolution into severely inflammatory and scarring lesions.

Diet

1.A potential role for diet in acne is controversial . A study of 47,355 women in the Nurses' Health Study that used a retrospective collection of data on diet during high school found an association between acne and intake of milk . The authors suggest that natural hormonal components of milk and/or other bioactive molecules in milk could exacerbate acne.

2.Other studies have suggested that insulin-like growth factor (IGF) may play a role in acne. IGF is increased by ingestion of high glycemic loads and so could potentially link diet and acne. A 12-week randomized trial that compared low and high glycemic load diets in 43 male patients with acne found a greater reduction in lesion counts with the low glycemic load diet . However, the participants on that diet also lost more weight than those on the high glycemic load diet, so it is possible that the results were due to changes in weight rather than the composition of the diet.



Stress

1.Patients and medical providers commonly believe that psychological stress can exacerbate acne . A prospective cohort study in 94 secondary school students compared acne severity and sebum production at times of high stress (midterm examinations) and low stress (summer holidays) . Sebum production did not appear to be related to stress, but acne severity, as assessed by an examiner blinded to the hypothesis of the study, did appear to be associated with stress, particularly in boys.

Similarly, a study of 22 university students found that in a multivariate analysis, acne severity did appear to have some correlation with stress around the time of school examinations.