F r o m the Academv This report reflects the best data available at the time the report was prepared, but caution should be exercised in interpreting the data. The results of future studies may require alteration of the conclusions or recommendations set forth in this report.
Report of the Consensus Conference on Acne Classification Washington, D.C., March 24 and 25, 1990 Planning Committee Members: Peter E. Pochi, MD, Chairman; Alan R. Shalita, MD, John S. Strauss, MD, and Stephen B. Webster, MD Other Consensus Panel members." William J. Cunliffe, MD, H. Irving Katz, MD, Albert M. Kligman, MD, James J. Leyden, MD, Donald P. Lookingbill, MD, Gerd Plewig, MD, Ronald M. Reisner, MD, Orlando G. Rodman, Jr., MD, Maria L. Turner, MD, and Guy F. Webster, MD, PhD A number of systems have been described for the classification of acne vulgaris, but there is no universally accepted method for assessing gradations of acne severity. As a result, determining whether a patient has severe acne or not becomes a subjective assessment. Furthermore, this lack of uniformity from one classification system to another has made it difficult to compare therapeutic efficacy among different studies. To address the issue of acne classification, the American Academy of Dermatology convened a Consensus Conference on Acne Classification in Washington, D.C., on March 24 and 25, 1990, in which a group of 14 expert clinicians and specialists interested in acne participated. In addition, representatives from the pharmaceutical industry were invited to attend as observers and were asked to offer their opinions. After lengthy discussion on the complex issues concerning the clinical rating of acne severity, two broad focus questions were addressed. Why is a suitable acne classification difficult to establish unequivocally? What elements should be considered in establishing ratings of severity and how are these modified by other considerations? Question 1: What are the diflicukies in establishing a standardized and reproducible system of classifying acne vulgaris? Reprint request: Department of Education, American Academy of Dermatology, 1567 Maple Ave., P.O. Box 3116, Evanston, IL 60204-3116. 16/8/26814
The central problem is that acne vulgaris is a highly pleomorphic disorder in which (1) there may be an admixture of both inflammatory and noninflammatory lesions involving multiple skin sites; (2) the inflammatory lesions vary in size, density, and severity of inflammation within localized sites of involvement in the same person, as well as among persons; and (3) there is considerable variability in the natural evolution and healing of lesions, and in the response to therapy.t To the members of the Consensus Conference, it seemed obvious from the outset that one of the more frequently used classification systems, dividing ache into four grades of severity,2-4 is overly simplistic. Other classifications have attempted to measure the number and extent of inflamed and noninflamed lesions.59 These semiquantitative classifications require special training for the user and seem better suited for the evaluation of new therapies in the investigative arena rather than for use in the clinical setting. Some methods have relied on standardized photographs to establish baseline observations and to document lesion types.9"t2Although photographs provide a permanent record, they may not accurately reflect disease activity. Photographs do not discriminate between macular and elevated lesions; in addition, small comedones may not be fully visualized, which result in their being underrecorded. Question 2: Should a standardized system of classification be based on lesion type, lesion count, global evaluation, or a combination thereof, and should the presence of scarring be considered in a 495
Journal of the American Academy of Dermatology
496 P o c h i et al.
Fig. 1. Mild papular acne. (Courtesy W. J. Cunliffe, MD, Leeds, England) Hg. 2. Moderate eomedonal and papuIopustular aene. (Courtesy W. J. Cunliffe, MD)
Table I. Severity grading of inflammatory acne lesions --
Severity
Mild Moderate Severe
.]
Papules/pustules
Nodules
Few to several Several to many Numerous and/or extensive
None Few to several Many
grading system? In addition, should psychosocial factors be considered, as well as the response to previous therapy? Acne lesions m a y be divided into inflammatory and noninflammatory lesions. Noninflammatory lesions consist of open and closed comedones. In general, acne manifested only by noninflammatory lesions can rarely be characterized as severe, unless the number, size, and extent of such lesions are so overwhelming as to warrant such a designation, (e.g., severe chloracne). Inflammatory acne is traditionally characterized
.
by the presence of one or more of the following types of lesions: papules, pustules, and nodules (cysts). Papules are inflammatory lesions less than 5 m m in diameter. Pustules are similar in size to papules but have a visible central core of purulent material Nodules are inflammatory lesions with a diameter of 5 m m or greater. These nodules may become suppurative or hemorrhagic. Nodular lesions, particularly when suppurative, have commonly been referred to as cysts because of their resemblance to inflamed epidermal cysts. The term cystic ache is frequently, although inaccurately, used to denote
Volume 24 Number 3 March 1991
Classification of acne vulgaris 49"/
Fig. 3. M~176176 in the central area of the cheek. (Courtesy W. J. Cunliffe, MD.) Fig. 4. M~176176 in the temporal and medial cheek regions. (Courtesy W. J. Cunliffe, MD.)
nodular ache. Rarely, true epidermal cysts may be a residual of healing ache lesions. In nodular acne, the inflammatory infiltrate is not always restricted to the immediate perifollicular area and may extend to involve nearby follicles. This may result in recurring rupture and reepithelialization, leading to epithelial-lined sinus tracks, often accompanied by disfiguring scars. This manifestation is known as conglobate ache. Severe, destructive variants of acne may also occur, presenting as ulceration and sometimes accompanied by fever and arthralgia (ache fulminans). Inflammatory ache lesions are usually located on one or more of the following sites: face, neck, back, and chest. Lesions sometimes extend beyond the trunk onto the buttocks and extremities. Often, the resolution of inflammatory lesions may leave erythematous and/or pigmented macules that can persist for months or longer.
In addition to the type and distribution of lesions, an aerie grading system should include assessments of the size and density of lesions, the intensity of lesional inflammation, formation of scars (atrophic and hypertrophic), and the presence of sinus tracks. Classification of acne on morphologic grounds seems to be feasible and reasonably reliable; however, quantification of severity is difficult. Although it is possible to count and describe each lesion according to size, such detail is not feasible in dayto-day clinical practice. Even if the size and number of different types of lesions could be determined practically, it is not obvious what relative importance should be given to the various types of lesions. It is the opinion of the Consensus Panel that acne grading can be best accomplished by the use of a pattern-diagnosis system, which would include a global (total) evaluation of lesions and their complications such as drainage, hemorrhage, and pain.
498
Pochi et al.
Journal of the American Academy of Dermatology
Fig. 5. Moderate nodular ache, with moderate and extensive papular disease. Slight scarfing is present. (Courtesy W. J. Cunliffe, MD.) Fig. 6. Severe papulopustular and nodular acne. (Courtesy W. J. Cunliffe, MD.) Furthermore, global evaluation takes into account the total impact of the disease, which may be influenced significantly by the disfigurement it causes. Other factors that m a y be involved in evaluating severity include occupational disability, the psychosocial impact, and the failure of response to previous therapies. The most destructive forms of the disease (i.e., acne conglobata, acne fulminans, and the follicular occlusion triad [acne inversa]) are undeniably severe. These entities are easily recognized and should be designated as very severe. At the opposite end of the spectrum, aerie comprised only of comedones, even when they are present in large numbers and/or are extensively distributed, can rarely be designated as severe. For inflammatory acne lesions, the Consensus Panel proposes that lesions be classified as papulopustular a n d / o r nodular. A severity grade based on a lesion count approximation would be assigned as mild, moderate, or severe, as shown in Table I. Illustrative examples of each category of severity
for both types of inflammatory lesions are shown in Figs. I through 8. Figs. 3, 4, and 5 show cases ofacne that can be considered severe, because of the presence, in cases shown in Figs. 4 and 5, of both nodular and inflammatory papules and/or pustules. In the case shown in Fig. 3, no nodules are apparent, but the presence of scarring and a moderately severe papular eruption would designate this as a severe case. A mild to moderate degree of scarring is also present in the other two cases. It should be readily appreciated that persons with moderate nodular acne will, more often than not, have varying degrees of paPular and/or pustular lesions as well, to an extent at times that the classification for that person can be deemed severe (i.e., moderate papulopustular plus moderate nodular acne would amount to severe inflammatory acne) (Fig. 5). As mentioned previously, other factors, in addition to the types and severity of inflammatory lesions shown in Table I, are important in assessing sever-
Volume 24 Number 3 March 1991
Classification of ache vulgaris 499
Fig. 7. Severe papulopustular and nodular acne. (Courtesy W. J. Cunliffe, MD.) Fig. 8. Severen~176176176
ity. These include ongoing scarring, persistent purulent and/or serosanguineous drainage from lesions, or the presence of sinus tracks. Moreover, additional factors are important in designating a patient as having severe acne. First, patients differ in the psychological, social, and even occupational consequences of their disease. These factors cannot be measured easily, but difficulty in their quantification does not diminish their importance. Second, acne patients who are clinically similar can respond differently to therapy. Thus when a patient is classified as having severe acne, factors of importance that complement the physical examination-derived grade include a history of resistance to prior therapy (which would also include treatment complications) and/or the impact of psychosocial circumstances in which ache of moderate severity might, on the cumulative basis of these considerations, be designated as severe.
The major conclusions of the Consensus Panel were as follows: 1. A strictly quantitative definition of acne severity cannot be established because of the variable expression of the disease. 2. The clinical diagnosis of severe acne should be based on the presence of any of the following characteristics: persistent or recurrent inflammatory nodules, extensive papul0pustular disease, ongoing scarring, persistent purulent and/or serosanguineous drainage from lesions, or the presence of sinus tracks. 3. In addition to the severity of a patient's clinical disease as determined by the examination of the skin, additional factors, from the patient's standpoint, are important in the designation of a particular case of ache as a severe one. These factors include psychosocial circumstances, occupational difficulties, and inadequate therapeutic responsiveness.
500
Pochi et aL
REFERENCES 1. IOigman AM. An overview of acne. J Invest Dermatol 1974;6:268-87. 2. Pillsbury DM, Shelley W-B, Kligrnan AM. Dermatology. Philadelphia: WB Saunders, 1956:810. 3. James KW, Tisserand JB Jr. Treatment of aene vulgaris. GP 1958;18:131-9. 4. Plcwig G, Kligman AM. Classification of ache vulgar'is. In: Aerie: morphogencsis and treatment. Berlin: Springer-Vetlag, 1975. 5. Witkowsld JA, Simons HM. Objective evaluation of demethylchlortetraeyeline hydrochlodde in the treatment of ache. JAMA 1966;196:111-4. 6. Michai~isson G, Juhlin L, Valalquist A. Effects of oral zinc and vitamin A in ache. Arch Dermatol 1977;113:31-6. 7. Christiansen J. Holm P, Reymarm F. The retinoic acid de-
Journal of the American Academy of Dermatology
rivative Ro 11-1430 in acnc vulgaris. Dcrmatologica 1977;154:219-27. 8. Allen BS, Smith JO Jr. Various parameters for grading ache vu]garis.Arch Dcrmatol 1982;118:23-5. 9. Burke BM, Cunliffe WJ. The assessment of acne vulgaris-the Leeds technique. Br J Dermatol 1984;111:83-92. 10. Cook CH, Cenmer RL, Michaels SE. An aene grading method using photographic standards. Arch Dermatol 1979;115:571-5. I 1. Wilson RG. Office application of a new ache grading system. Cuds 1980;25:62-4. 12. Samuelson JS. An accurate photographic method for grading acne: initial use in a double-blind clinical comparison of minocycline and tetracycline. J AM ACAD DERMATOL 1985;12:461-7.
Report of the Consensus Conference on Acne Classification Washington, D.C., March 24 and 25, 1990 Planning Committee Members: Peter E. Pochi, MD, Chairman; Alan R. Shalita, MD, John S. Strauss, MD, and Stephen B. Webster, MD Other Consensus Panel members." William J. Cunliffe, MD, H. Irving Katz, MD, Albert M. Kligman, MD, James J. Leyden, MD, Donald P. Lookingbill, MD, Gerd Plewig, MD, Ronald M. Reisner, MD, Orlando G. Rodman, Jr., MD, Maria L. Turner, MD, and Guy F. Webster, MD, PhD A number of systems have been described for the classification of acne vulgaris, but there is no universally accepted method for assessing gradations of acne severity. As a result, determining whether a patient has severe acne or not becomes a subjective assessment. Furthermore, this lack of uniformity from one classification system to another has made it difficult to compare therapeutic efficacy among different studies. To address the issue of acne classification, the American Academy of Dermatology convened a Consensus Conference on Acne Classification in Washington, D.C., on March 24 and 25, 1990, in which a group of 14 expert clinicians and specialists interested in acne participated. In addition, representatives from the pharmaceutical industry were invited to attend as observers and were asked to offer their opinions. After lengthy discussion on the complex issues concerning the clinical rating of acne severity, two broad focus questions were addressed. Why is a suitable acne classification difficult to establish unequivocally? What elements should be considered in establishing ratings of severity and how are these modified by other considerations? Question 1: What are the diflicukies in establishing a standardized and reproducible system of classifying acne vulgaris? Reprint request: Department of Education, American Academy of Dermatology, 1567 Maple Ave., P.O. Box 3116, Evanston, IL 60204-3116. 16/8/26814
The central problem is that acne vulgaris is a highly pleomorphic disorder in which (1) there may be an admixture of both inflammatory and noninflammatory lesions involving multiple skin sites; (2) the inflammatory lesions vary in size, density, and severity of inflammation within localized sites of involvement in the same person, as well as among persons; and (3) there is considerable variability in the natural evolution and healing of lesions, and in the response to therapy.t To the members of the Consensus Conference, it seemed obvious from the outset that one of the more frequently used classification systems, dividing ache into four grades of severity,2-4 is overly simplistic. Other classifications have attempted to measure the number and extent of inflamed and noninflamed lesions.59 These semiquantitative classifications require special training for the user and seem better suited for the evaluation of new therapies in the investigative arena rather than for use in the clinical setting. Some methods have relied on standardized photographs to establish baseline observations and to document lesion types.9"t2Although photographs provide a permanent record, they may not accurately reflect disease activity. Photographs do not discriminate between macular and elevated lesions; in addition, small comedones may not be fully visualized, which result in their being underrecorded. Question 2: Should a standardized system of classification be based on lesion type, lesion count, global evaluation, or a combination thereof, and should the presence of scarring be considered in a 495
Journal of the American Academy of Dermatology
496 P o c h i et al.
Fig. 1. Mild papular acne. (Courtesy W. J. Cunliffe, MD, Leeds, England) Hg. 2. Moderate eomedonal and papuIopustular aene. (Courtesy W. J. Cunliffe, MD)
Table I. Severity grading of inflammatory acne lesions --
Severity
Mild Moderate Severe
.]
Papules/pustules
Nodules
Few to several Several to many Numerous and/or extensive
None Few to several Many
grading system? In addition, should psychosocial factors be considered, as well as the response to previous therapy? Acne lesions m a y be divided into inflammatory and noninflammatory lesions. Noninflammatory lesions consist of open and closed comedones. In general, acne manifested only by noninflammatory lesions can rarely be characterized as severe, unless the number, size, and extent of such lesions are so overwhelming as to warrant such a designation, (e.g., severe chloracne). Inflammatory acne is traditionally characterized
.
by the presence of one or more of the following types of lesions: papules, pustules, and nodules (cysts). Papules are inflammatory lesions less than 5 m m in diameter. Pustules are similar in size to papules but have a visible central core of purulent material Nodules are inflammatory lesions with a diameter of 5 m m or greater. These nodules may become suppurative or hemorrhagic. Nodular lesions, particularly when suppurative, have commonly been referred to as cysts because of their resemblance to inflamed epidermal cysts. The term cystic ache is frequently, although inaccurately, used to denote
Volume 24 Number 3 March 1991
Classification of acne vulgaris 49"/
Fig. 3. M~176176 in the central area of the cheek. (Courtesy W. J. Cunliffe, MD.) Fig. 4. M~176176 in the temporal and medial cheek regions. (Courtesy W. J. Cunliffe, MD.)
nodular ache. Rarely, true epidermal cysts may be a residual of healing ache lesions. In nodular acne, the inflammatory infiltrate is not always restricted to the immediate perifollicular area and may extend to involve nearby follicles. This may result in recurring rupture and reepithelialization, leading to epithelial-lined sinus tracks, often accompanied by disfiguring scars. This manifestation is known as conglobate ache. Severe, destructive variants of acne may also occur, presenting as ulceration and sometimes accompanied by fever and arthralgia (ache fulminans). Inflammatory ache lesions are usually located on one or more of the following sites: face, neck, back, and chest. Lesions sometimes extend beyond the trunk onto the buttocks and extremities. Often, the resolution of inflammatory lesions may leave erythematous and/or pigmented macules that can persist for months or longer.
In addition to the type and distribution of lesions, an aerie grading system should include assessments of the size and density of lesions, the intensity of lesional inflammation, formation of scars (atrophic and hypertrophic), and the presence of sinus tracks. Classification of acne on morphologic grounds seems to be feasible and reasonably reliable; however, quantification of severity is difficult. Although it is possible to count and describe each lesion according to size, such detail is not feasible in dayto-day clinical practice. Even if the size and number of different types of lesions could be determined practically, it is not obvious what relative importance should be given to the various types of lesions. It is the opinion of the Consensus Panel that acne grading can be best accomplished by the use of a pattern-diagnosis system, which would include a global (total) evaluation of lesions and their complications such as drainage, hemorrhage, and pain.
498
Pochi et al.
Journal of the American Academy of Dermatology
Fig. 5. Moderate nodular ache, with moderate and extensive papular disease. Slight scarfing is present. (Courtesy W. J. Cunliffe, MD.) Fig. 6. Severe papulopustular and nodular acne. (Courtesy W. J. Cunliffe, MD.) Furthermore, global evaluation takes into account the total impact of the disease, which may be influenced significantly by the disfigurement it causes. Other factors that m a y be involved in evaluating severity include occupational disability, the psychosocial impact, and the failure of response to previous therapies. The most destructive forms of the disease (i.e., acne conglobata, acne fulminans, and the follicular occlusion triad [acne inversa]) are undeniably severe. These entities are easily recognized and should be designated as very severe. At the opposite end of the spectrum, aerie comprised only of comedones, even when they are present in large numbers and/or are extensively distributed, can rarely be designated as severe. For inflammatory acne lesions, the Consensus Panel proposes that lesions be classified as papulopustular a n d / o r nodular. A severity grade based on a lesion count approximation would be assigned as mild, moderate, or severe, as shown in Table I. Illustrative examples of each category of severity
for both types of inflammatory lesions are shown in Figs. I through 8. Figs. 3, 4, and 5 show cases ofacne that can be considered severe, because of the presence, in cases shown in Figs. 4 and 5, of both nodular and inflammatory papules and/or pustules. In the case shown in Fig. 3, no nodules are apparent, but the presence of scarring and a moderately severe papular eruption would designate this as a severe case. A mild to moderate degree of scarring is also present in the other two cases. It should be readily appreciated that persons with moderate nodular acne will, more often than not, have varying degrees of paPular and/or pustular lesions as well, to an extent at times that the classification for that person can be deemed severe (i.e., moderate papulopustular plus moderate nodular acne would amount to severe inflammatory acne) (Fig. 5). As mentioned previously, other factors, in addition to the types and severity of inflammatory lesions shown in Table I, are important in assessing sever-
Volume 24 Number 3 March 1991
Classification of ache vulgaris 499
Fig. 7. Severe papulopustular and nodular acne. (Courtesy W. J. Cunliffe, MD.) Fig. 8. Severen~176176176
ity. These include ongoing scarring, persistent purulent and/or serosanguineous drainage from lesions, or the presence of sinus tracks. Moreover, additional factors are important in designating a patient as having severe acne. First, patients differ in the psychological, social, and even occupational consequences of their disease. These factors cannot be measured easily, but difficulty in their quantification does not diminish their importance. Second, acne patients who are clinically similar can respond differently to therapy. Thus when a patient is classified as having severe acne, factors of importance that complement the physical examination-derived grade include a history of resistance to prior therapy (which would also include treatment complications) and/or the impact of psychosocial circumstances in which ache of moderate severity might, on the cumulative basis of these considerations, be designated as severe.
The major conclusions of the Consensus Panel were as follows: 1. A strictly quantitative definition of acne severity cannot be established because of the variable expression of the disease. 2. The clinical diagnosis of severe acne should be based on the presence of any of the following characteristics: persistent or recurrent inflammatory nodules, extensive papul0pustular disease, ongoing scarring, persistent purulent and/or serosanguineous drainage from lesions, or the presence of sinus tracks. 3. In addition to the severity of a patient's clinical disease as determined by the examination of the skin, additional factors, from the patient's standpoint, are important in the designation of a particular case of ache as a severe one. These factors include psychosocial circumstances, occupational difficulties, and inadequate therapeutic responsiveness.
500
Pochi et aL
REFERENCES 1. IOigman AM. An overview of acne. J Invest Dermatol 1974;6:268-87. 2. Pillsbury DM, Shelley W-B, Kligrnan AM. Dermatology. Philadelphia: WB Saunders, 1956:810. 3. James KW, Tisserand JB Jr. Treatment of aene vulgaris. GP 1958;18:131-9. 4. Plcwig G, Kligman AM. Classification of ache vulgar'is. In: Aerie: morphogencsis and treatment. Berlin: Springer-Vetlag, 1975. 5. Witkowsld JA, Simons HM. Objective evaluation of demethylchlortetraeyeline hydrochlodde in the treatment of ache. JAMA 1966;196:111-4. 6. Michai~isson G, Juhlin L, Valalquist A. Effects of oral zinc and vitamin A in ache. Arch Dermatol 1977;113:31-6. 7. Christiansen J. Holm P, Reymarm F. The retinoic acid de-
Journal of the American Academy of Dermatology
rivative Ro 11-1430 in acnc vulgaris. Dcrmatologica 1977;154:219-27. 8. Allen BS, Smith JO Jr. Various parameters for grading ache vu]garis.Arch Dcrmatol 1982;118:23-5. 9. Burke BM, Cunliffe WJ. The assessment of acne vulgaris-the Leeds technique. Br J Dermatol 1984;111:83-92. 10. Cook CH, Cenmer RL, Michaels SE. An aene grading method using photographic standards. Arch Dermatol 1979;115:571-5. I 1. Wilson RG. Office application of a new ache grading system. Cuds 1980;25:62-4. 12. Samuelson JS. An accurate photographic method for grading acne: initial use in a double-blind clinical comparison of minocycline and tetracycline. J AM ACAD DERMATOL 1985;12:461-7.
