NICHOLAS A.
`HOWARD P. BADEN
`
`1 of 18
`
`Almirall EXHIBIT 2027
`Amneal v. Almirall
`IPR2018-00608
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`

`

`One of the editors (N.A.S.) dedicates this book to his mother,
`Mildred Elizabeth Sorer, and the other editor (H.P.B.) dedicates
`this book to his family.
`
`PATHOPHYSIOLOGY OF DERMATOLOGIC DISEASES
`
`Copyright © 1991, 1984 by McGraw-Hill, Inc. All rights reserved. Printed in
`the United States of America. Except as permitted under the United States
`Copyright Act of 1976, no part of this publication may be reproduced or
`distributed in any form or by any means, or stored in a data base or retrieval
`system, without the prior written permission of the publisher.
`
`1234567890 HALHAL 9876543210
`
`ISBN 0-07-059747-2
`
`This book was set in Palatino by Monotype Composition, Inc.; the editors were
`William Day and Lester A. Sheinis; the production supervisor was Clare Stanley;
`the cover was designed and the project was supervised by M "N O Production
`Services, Inc.
`Halliday Lithograph Corporation was printer and binder.
`
`Library of Congress Cataloging-in-Publication Data
`
`Pathophysiology of dermatologic diseases / [edited by] Nicholas A.
`Soter, Howard P. Baden. -- 2d ed.
`p. crn.
`Includes bibliographical references.
`Includes index.
`ISBN 0-07-059747-2
`1. Skin Pathophysiology. I. Soter, Nicholas A. II. Baden,
`Howard P.
`[DNLM: 1. Skin Diseases---physiopathology. WR 140 P297]
`RL96.P37 1991
`616.5---dc20
`DNLM/DLC
`for Library of Congress
`
`90-6646
`CIP
`
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`13
`
`Biology of the
`Sebaceous Gland and
`the Pathophysiology
`of Acne Vulgaris
`
`John S. Strauss
`
`BIOLOGY OF SEBACEOUS GLANDS
`
`Sebaceous glands are found everywhere on the human skin except for
`the pahns, soles, and dorsa of the feet. The sebaceous glands are part of
`tile pilosebaceous unit, and their secretion (sebum) flows through the
`sebaceous duct into the follicular canal. Sebaceous glands also are found
`on some mucous membranes. Those in the mouth empty directly onto the
`surface through the gland duct itself. There is great variation in the size
`and density of the glands; more glands and larger glands are found on the
`face and scalp compared with other areas of the body. On much of the face
`in adults, the sebaceous glands are the predominant portion of the follicle.
`These follicles are called sebaceous follicles (Fig. 13-1) and are the follicles
`that are involved in ache.
`Sebaceous cells enlarge and contain more lipid as they move in a
`centripetal direction to the center of the sebaceous acini. Mitotic activity
`is restricted to the peripheral basal cell layer of the gland. Therefore
`sebaceous gland development involves both mitosis and lipogenesis, and
`there is evidence that these two processes are independently controlled.
`Sebaceous gland secretion is a continuous process and is holocrine in
`nature. However, the capacity of the unprotected skin to hold lipid is
`limited, and therefore excess lipid is lost. If the skin is protected, the lipid
`will continue to accumulate.
`
`195
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`196 Disorders of the Epidermal Appendages
`
`i!i
`
`¯
`
`o
`
`°?
`
`°Z~¯
`
`":"
`
`¯ ,q,I
`.,.0~
`
`,o
`
`.r.
`
`Figure 13-1 Sebacet,us follicle /rom tilt, human cheek. ’Ihe sebaceous ducts, as well as the
`widely dilated follicular canal, are filled with keratinous material. A small velhls hair is
`present. [From TB tilzpatrwk el al (eds), D~’rmatolo~! In Gcm’ral Medwinc, 3d ed, New Yorl,,
`McGraw-HilL 1987, p 180.1
`
`Sebaceous gland growth is under endocrinologic control.~ ~ The prime
`stimulus for growth in the male is testicular testosterone and its metabolic
`products such as dihydrotestosterone. In the female, ovarian and adrenal
`androgens are probably responsible for gland growth. While the glands
`are large at birth, they undergo atrophy soon afterward and do not enlarge
`again until the beginning of puberty. Since the sebaceous glands are
`androgen sensitive, their growth is one of the earliest signs of the pubertal
`spectrum. After puberty, the glands remain stable in size. in women, they
`undergo atrophy during menopause, but in nlen sebaceous gland activity
`
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`The Sebaceous Gland and Acne Vulgaris 197
`
`is maintained until approximately 70 years of age. While androgens are of
`prime importance, there is an important pituitary influence on sebaceous
`gland activity, and in hypopituitarism, sebaceous gland activity is markedly
`diminished.
`Physiological amounts of estrogens do not influence sebaceous gland
`development and, therefore, are unimportant in the normal control of the
`sebaceous gland. However, pharmacologic amounts of estrogen do de-
`crease sebaceous gland activity.4 This effect is mediated through central
`inhibition of androgen production. This finding is used in the treatment
`of severe acne in women,s
`Because the sebaceous glands are deep in the dermis and do not open
`directly to the skin surface, it has not been possible to collect sebum, the
`product of the sebaceous glands, directly. Therefore, skin surface lipids
`have been used to study sebaceous gland secretion and sebum composition.
`The skin surface lipids represent a two-compartment system in that they
`originate from both the epidermis and the sebaceous glands. Since
`sebaceous and epidermal lipids are distinctly different, the composition of
`the skin surface lipids will vary depending upon whether the major portion
`is derived from the epidermis or the sebaceous glands.(’ The approximate
`composition of sebum and epidermal lipid is given in Table 13-1. Triglyc-
`erides and their breakdown products make up approximately two-thirds
`of both epidermal and sebaceous lipids. Therefore, the concentration of
`triglycerides and their breakdown products does not vary significantly as
`the percentage of sebaceous and epidermal lipids changes. On the other
`hand, since triglycerides are hydrolyzed by bacterial lipases, the concen-
`trations of triglycerides, diglycerides, and free fatty acids may vary greatly
`in a given individual under various conditions.
`Besides triglycerides, the epidermal lipids are cholesterol and cholesterol
`esters. In contrast, less than 5 percent of sebaceous lipids are cholesterol
`and cholesterol esters. Wax esters and squalene are uniquely of sebaceous
`origin and represent the major nontriglyceride fraction of sebum. Therefore,
`
`Table 13-1
`
`APPROXIMATE COMPOSITION OF SEBUM AND
`EPIDERMAL LIPID
`
`Glycerides and free fatty acids
`Wax esters
`Squalene
`Cholesterol esters
`Cholesterol
`
`Sebum,
`wt (’Y,)
`
`57.5
`26.0
`12.0
`3.0
`1.5
`
`Epidermal
`Lipid
`wt (’~)
`
`65
`--
`--
`15
`20
`
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`198 Disorders of the Epidermal Appendages
`
`if most of the skin surface lipids are of epidermal origin, as in childhood,
`the cholesterol content will be high, whereas the concentration of wax
`esters and squalene will be low.7 If, however, most of the skin surface
`lipid is of sebaceous origin, as in the adult, in whom over 95 percent of
`facial lipid is from the sebaceous glands,~ the wax ester and squalene
`content is high, whereas the cholesterol level is low. Under appropriate
`conditions, the relative amounts of cholesterol and wax esters or squalene
`in skin surface lipids can be used as an indication of the relative sebaceous
`and epidermal contributions to the skin surface lipid.
`Since the sebaceous glands are holocrine structures, their secretory
`activity provides a rough measurement of gland size, and for many years
`measurements of sebum production have been used to study changes in
`sebaceous gland activity. It is best to collect the lipids of the forehead by
`trapping them on absorbing materials such as paper~ or a dried bentonite
`slurry.~ Then the trapped lipid is extracted for quantitative or qualitative
`analysis. An essential element that must be considered is the contribution
`of the lipid reservoir of the epidermis. In the most common method, in
`use for over 20 years, surface lipids are depleted for only 30 minutes.8 It
`has now been established that cutaneous reservoir depletion takes as long
`as 12 to 14 h, and a new collection method takes this fact into consideration.9
`The surface samples are obviously contaminated by epidermal lipids, but
`less than 5 percent of forehead lipids are of epidermal origin. Therefore,
`within the limits of the technique, the collected lipids do represent a
`measure of sebum production and can be used to detect physiological as
`well as drug-induced changes in sebaceous glands.
`
`ACNE VULGARIS
`
`Acne vulgaris is usually classified as a disease of the sebaceous glands,
`but it should be classified as a disease of the pilosebaceous unit since the
`lesions develop in the upper portion of the follicular canal and do not
`involve the glands primarily. Acne is the mosi common disease seen by
`dermatologists, accounting for over 25 percent of all dermatologic office
`visits. Physicians involved in primary care delivery are also likely to see
`acne as a presenting complaint quite frequently. Nonetheless, since 80 to
`90 percent of all individuals develop some acne in the second and third
`decades, it is obvious that only a small percentage of those with acne
`actually consult physicians.
`Acne is occasionally present at birth or in the neonatal period. However,
`it is not until puberty that it becomes a common problem. The disease
`may be an early manifestation of tile pubertal spectrum, and in young
`females it may precede menarche by more than a year. Acne reaches a
`peak incidence during the middle to late teenage period, and then the
`number of cases gradually decreases. In women, acne may persist through
`the third decade or even later. Ache is slightly more common in males,
`and severe ache is definitely more common in males.
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`5ubje~: USCopyricht Laws
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`The Sebaceous Gland and Acne Vulgaris 199
`
`Etiology and Pathogenesis
`
`While the basic cause of acne is unknown, there is considerable
`information on its pathogenesis. The disease is multifactorial. Knowledge
`of the various factors involved in the disease is important, since treatment
`may be directed at one or more of these causative factors.
`Acne develops in sebaceous follicles (Fig. 13-1). These follicles open to
`the surface by a widely dilated follicular orifice (visible as the so-called
`pore of the skin of the face) and are wide throughout their entire length.
`A vellus hair is always present in the follicle, but as it is very small, it
`may not be apparent from examination of a single microscopic section.
`Short ducts connect the huge, deeply situated, multiacinar glands to the
`large follicular duct.
`The follicular canal contains keratinous material from the wall of the
`canal, sebum from the sebaceous glands, and a variable microbial flora.
`These are all involved m the pathogenesis of the disease.
`The primary structural change is an alteration in the pattern of kerati-
`nization in the lower portion of the follicular infundibulum (the infrain-
`fundibulum).l" Normally the keratinous squamae in the follicular canal are
`loosely organized. In the earliest lesion (the microcomedo), which is not
`visible clinically, the keratinous material becomes more dense. The cells
`of the microcomedo are much more coherent and contain amorphous
`material, which is probably generated by lipid during the process of
`keratinization. Kinetic studies have demonstrated that there is an increase
`in cellular turnover, so that more cells are generated per unit period of
`time.t~
`As a group, patients with acne produce more sebum than do normal
`persons, and patients with severe acne secrete more sebum than those
`with mild acne.~2 Nevertheless, there is considerable variation in sebum
`production within the group of patients with acne, indicating that the
`disease is not related solely to sebaceous gland activity. Many other facts
`indicate that sebum plays a role in the overall pathogenesis of the disease.
`These include the following: sebum is comedogenic’~; sebum causes
`inflammation when injected into the skin~4; acne occurs in the neonatal
`period when the sebaceous glands are well developed; acne appears as
`part of the pubertal spectrum at a time when sebaceous gland development
`occurs; and acne can be controlled by orally administered estrogens,
`antiandrogens such as cyproterone acetate, and spironolactone and reti-
`noids, all of which inhibit sebaceous gland activity.
`Several studies have been done to attempt to demonstrate that sebum
`from acne patients is different from that in normal individuals. In general,
`no consistent patterns of change have been observed.> However, there is
`a significant decrease in the level of linoleic acid in sebum,~’ and consid-
`erable evidence has been presented to link the low levels of linoleic acid
`to the pathogenesis of acne.~r It has been postulated that the low levels
`of linoleic acid represent the dilution of this essential fatty acid, which is
`
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`200 Disorders of the Epidermal Appendages
`
`not synthesized in the sebaceous glands, by the newly synthesized
`sebaceous lipids in the large sebaceous glands characteristically found in
`patients with acne. In turn, the low concentration of linoleate in sebum
`induces a localized essential follicular fatty acid deficiency, with the
`characteristic responses of hyperkeratosis and decreased barrier function
`within the follicle.Z7
`The predominant organism in the follicular flora is an anaerobic pleo-
`morphic diphtheroid, Propionibacterium aches. In the acne age range from
`11 to 15 years, practically no P. aches are found in individuals without
`acne, whereas in patients with acne the geometric mean is 114,800 P. aches
`per square centimeter.IS Similar differences are found in 16- to 20-year-old
`groups, but in older individuals the number of organisms is the same in
`those with and without ache. While staphylococci, micrococci, and yeasts
`(Pityrosporum species) are also found in the follicle, there is no evidence
`that they are involved in the acne process.
`In spite of the importance of P. aches in the pathogenesis of acne, acne
`is not a bacterial disease per se, and its response to therapy with antibiotics
`is not what one would expect from a bacterial disease. Instead, P. aches
`generates inflammatory agents. Extracellular products of P. aches include
`enzymes such as lipases, proteases, and hyaluronidases, as well as
`chemotactic factors. It is these extracellular products and, in turn, their
`products that cause inflammatory changes.
`Indirect evidence that P. aches is responsible for lipolysis and inflam-
`mation is supplied by experiments in which suspensions of this organism
`have been injected into cysts. ’~ The injection of viable organisms causes
`rupture of the cysts and severe inflammation of the surrounding tissues.
`Very little inflammation is produced by the injection of nonviable organisms
`into cysts, and injection of living organisms into the dermis induces only
`a slight to moderate infiltrate of neutrophils.
`
`Clinical Manifestations
`
`The primary site of acne is the face, and to a lesser degree the back,
`chest, and shoulders. On the trunk, lesions tend to be more numerous
`near the midline. Acne is a pleomorphic disease consisting of noninflam-
`matory and inflammatory lesions. While one type of lesion may be
`predominant, close observation usually reveals several types of lesions.
`Comedones, which are the primary lesions of ache, are noninflammatory
`(Fig. 13-2). Closed comedones (whiteheads) may be difficult to visualize.
`They appear as pale, slightly elevated, small papules. They often do not
`have a clinically visible orifice. Stretching of the skin is an aid in detecting
`these lesions. Since the dosed comedones are the precursors of the large
`inflammatory lesions, they are of considerable clinical importance. Open
`comedones (blackheads) develop from closed comedones as the orifice
`dilates. The open comedo is flat or slightly raised, with a central follicular
`impaction. While comedones are the primary lesions of acne, they are not
`
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`The Sebaceous Gland and Acne Vulgaris 201
`
`unique to this disease, since they may be seen under other conditions
`(e.g., so-called senile comedones commonly seen in the periorbital area of
`older persons).
`Inflammatory lesions in acne vary from small papules with an inflam-
`matory areola to pustules to large, tender, fluctuant nodules (Fig. 13-3).
`All these lesions show an inflammatory infiltrate in the dermis and, as
`indicated below, have a common pathogenesis; their appearance depends
`on the size and location of the infiltrate.
`
`Pathology
`
`Comedo development starts in the midportion of the follicle as an
`expanding mass of lipid-impregnated keratinous material, resulting in
`thinning and ballooning of the follicular wall. Gradually, more keratinous
`material accumulates, and, as it does, further thinning and dilatation of
`the follicular wall occur. The fully formed comedo has a thin wall and
`minute sebaceous appendages, if these can be found at all. The open
`comedo has a patulous orifice, and the keratinous material is arranged in
`a lamellar concentric fashion (Fig. 13-4). With lipid stains, it can be shown
`that the keratin is permeated by lipid. P. aches is alo present. In cross
`sections, the orderly arrangement of the keratinous material consists of
`smaller whorls of lamellar material centered on appendageal structures
`such as the hairs. In fact, most comedones contain multiple hairs. The
`closed comedo differs from the open comedo in that the keratinous material
`is not as compact, as the follicular orifice is narrow and not distended
`(Fig. 13-5).
`The fully developed open comedo usually is not the site of inflammatory
`changes unles it is traumatized by the patient. Inflammatory changes
`develop in closed comedones. Initially there is an area of inflammation
`along the follicular wall, which then ruptures. Once complete rupture has
`occurred, the entire contents of the comedo are extruded into the dermis,
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`202 1)i~orders of the I(pidcrmal Appendages
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`The Sebaceous Gland and Acne Vulgaris 203
`
`Figure 13-4 Open comedo. The mouth of the follicle is widely dilated. The comedo is
`composed of a lamellar keratinous mass impregnated with lipid. Bacteria are also present.
`The sebaceous glands have undergone atrophy. (From IS Straz~ss, AM Kligmat;.’~)
`
`¯ ~: ,, ’~;:’
`
`Figure 13-5 Closed comedo. The structure of the lesion is similar to that of the open comedo.
`However, the orifice is small and the contents of the comedo are not as compact. (Fn~m IS
`Stn~t~ss, AM Kli,gma~.’*)
`
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`204 Disorders of the Epidermal Appendages
`
`Figure 13-6 Ruptured closed comedo. In the upper portion of the lesion there is lamellar
`keratinous material from the comedo. Below this, necrotic material is being encapsulated by
`new epithelial cells. These new cells are shown in higher magnification in the insert.
`Multinucleated giant cells are present in the inflammatory infiltrate in the dermis. (From ]S
`Strauss, AM Kligman.l~)
`
`exciting a greater inflammatory response. Depending upon the site and
`extent of the inflammation, these ruptured lesions may appear as a pustule,
`a nodule, or a nodule surmounted by a pustule.
`The sheaths of cells grow out from the epidermis and/or the appendageal
`structures in an attempt to encapsulate the inflammatory reaction (Fig.
`13-6). This encapsulation may be complete, so that the inflammatory
`infiltrate appears to be within the follicle, but it often is far from complete,
`and further rupture may occur, leading to multichanneled tracts, as can
`be seen in many acne scars. Fibrous contraction also contributes to scar
`formation.
`
`Therapy
`
`There are four principles of therapy, which are based on the current
`knowledge of the pathogenesis of the disease. These principles are: (1)
`correct the pattern of altered keratinization within the follicle, (2) decrease
`sebaceous gland activity, (3) decrease the P. aches population and/or
`decrease the generation of inflammatory substances by the bacterial
`population, and (4) produce anti-inflammatory effects. However, rigid
`guidelines cannot be established, since there is likely to be considerable
`overlap in the type of lesions in any one case, and often combination
`therapy is indicated.
`
`To Correct the Defect in Keratinization
`
`The most effective drug used to change the pattern of keratinization is
`topically applied vitamin A acid. Vitamin A acid is comedolytic,2° and at
`
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`=: the NLM and may be
`~ubjs~’t US Cop/right Laws
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`The Sebaceous Gland and Ache Vulgaris 205
`
`an ultrastructural level the process of follicular wall keratinization returns
`toward normal.2~ The drug may produce irritation, and some patients
`cannot tolerate its use, even if it is applied as infrequently as every 2 or 3
`days. Patients should be cautioned about sun exposure while using vitamin
`A, because the drug may cause an exaggerated sunburn. Salicylic acid also
`is comedolytic. Benzoyl peroxide, although predominantly an antibacterial
`agent, also has weak comedolytic activity.
`When acne surgery is done, the comedo is extruded to the skin surface;
`thus this procedure can be considered an aid in changing the pattern of
`keratinization. If acne surgery is not performed with care, the contents of
`the comedo can be extruded into the dermis, resulting in increased
`inflammation. For this reason, this procedure should be done by a trained
`person and not by the patient.
`
`To Decrease Sebaceous Gland Activity
`
`Suppression of sebaceous gland activity is important in treating acne,
`especially inflammatory acne. It is known that pharmacologic dosages of
`estrogens will inhibit sebaceous glands,4 and estrogens, usually given as
`oral contraceptives containing high concentrations of estrogen, may be
`used in the management of acne) Estrogens are not indicated for routine
`use; they should be given to women with recalcitrant acne, and the
`physician must assess the risk/benefit ratio carefully before starting any
`patient on therapy. Since estrogens do not have any known effect on
`existing lesions but appear to work by limiting the contribution of sebum
`to the inflammatory process in new lesions, their clinical effect is delayed
`while the preexisting lesions undergo their natural involution.
`There are new developments in the use of antiandrogens in the
`management of acne. Cyproterone acetate, used in conjunction with
`estrogen (an oral contraceptive combination available in Europe), is more
`effective in suppressing sebum production and improving acne than
`estrogen alone in women22; cyproterone acetate given alone is effective in
`men, although it has many side effects.2s While cyproterone acetate is not
`available in the United States, spironolactone, which also has locally acting
`antiandrogenic properties, has been shown to be useful in the management
`of severe acne.2~
`There is evidence that a few patients with acne have partial hydroxylase
`blocks that influence adrenal steroid metabolism, leading to increased
`androgen production.2~ In these patients, excess androgen production can
`be blocked by the administration of exogenous adrenocorticosteroids
`through a feedback mechanism.
`Probably the most exciting development in acne therapy in recent years
`has been the use of the synthetic oral retinoid, isotretinoin (13-cis-retinoic
`acid). This drug has proved to be extremely effective in the control of
`severe nodulocystic acne.=" Not only has it produced remarkable improve-
`ment, but the remissions after cessation of treatment have been very
`long.27 While there may be long-term inhibition of sebaceous gland
`secretion, this is by no means seen in all patients2~ and cannot be considered
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`206 Disorders of tile Epidermal Appendages
`
`the sole reason for the long-term remissions. The other possible mecha-
`nisms of action, as well as the clinical effectiveness of isotretinoin, have
`recently been summarized.2" The drug also has been shown to be effective
`in controlling disorders of keratinization and to have anti-inflammatory
`effects, but these activities do not explain the protracted remissions. P.
`acues counts are suppressed for long periods of time,~" but it is not known
`whether tile decrease is responsible for the long-term remissions.
`The excitement surrounding the use of isotretinoin must be tempered
`by the many side effects produced by this drug. In essence, every patient
`treated with isotretinoin develops signs and symptoms of chronic hyper-
`vitaminosis A. Most of these side effects are integumentary {dry skin, dry
`mucous membranes, cheilitis, dermatitis, pruritus, desquamation of the
`palms and soles). Certain laboratory abnormalities, such as a reversible
`hypertriglyceridemia accompanied by a decrease in high-density lipopro-
`reins, are also common. Other side effects, such as skeletal hyperkeratosis
`and pseudotumor cerebri, both of which are part of the hypervitaminosis
`A syndrome, have also been reported. Of greatest importance, however,
`is the fact that the drug, while not mutagenic, has marked teratogenic
`effects on organogenesis during early fetal development. Retinoid embry-
`opathy is severe)l The problem is a serious one,p and because of this,
`there are strict guidelines* for its use in women of childbearing age.x~
`These guidelines must be followed, and those physicians who are not well
`informed and well trained in the use of isotretinoin should not use the
`drug under any circumstances.
`Superficial x-ray therapy can produce temporary inhibition of the
`sebaceous glands. Although it was used in the past for the treatment of
`acne, it is not used now.
`
`To Reduce the P. aches Population
`
`P. aches is probably responsible for the generation of inflammatory
`substances; therefore, the suppression of the intrafollicular bacterial pop_
`ulation is important in controlling inflammatory acne. Benzoyl peroxide is
`an extremely effective topical antimicrobial agent,~4 and preparations
`containing benzoyl peroxide are the most popular agents for the topical
`control of the follicular P. acnt’s population. Topical antimicrobials are used
`for the same purpose.
`Orally administered antibiotics are widely used in the treatment of acne.
`In fact, 10 percent of all tetracycline sold in the United States is used for
`the treatment of acne. Since acne is not a bacterial disease per se, the
`therapeutic response is not fast, as in true bacterial infections such as
`cellulitis. Improvement may take a month or more, since that much time
`is required for the existing lesions to undergo involution. While tetracycline
`is the most commonly used antibiotic for acne, erythromycin is equally
`effective. Minocvcline is probably the most effective antibiotic for control-
`
`*(htiddlm’s arc also pnmidrd b.II till’ ItlI1HIt~II(’IItF(’F iH IIR" lJll(kak’~’ IIl:q’rl.
`
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`The Sebaceous Gland and Acne Vulgaris 207
`
`ling the inflammatory component of acne, but its comparative cost at this
`time precludes its use unless the patient does not respond to other
`antibiotics. In addition, pigment deposition may occur in the skin during
`minocycline therapy.
`A rare complication of antibiotic therapy is the development of a gram-
`negative folliculitis)5 With prolonged antibiotic therapy, gram-negative
`organisms may proliferate in the anterior nares and spread out onto the
`surrounding skin. The clinical lesions of gram-negative folliculitis are either
`multiple pustules with an intense inflammatory areola or deep, indolent
`nodules. This complication may easily be overlooked and is suggested by
`a sudden inflammatory flare with pustules or nodules in a patient who is
`otherwise improving on antibiotic therapy. Culture is necessary, and
`appropriate antibiotic therapy should be governed by the results of
`sensitivity studies.
`
`To Produce an Anti-inflammatomy Effect
`
`The anti-inflammatory effect of adrenocorticosteroids may be utilized in
`the treatment of acne. It is preferable to use them intralesionally in order
`to prevent the side effects that may follow high-dose oral therapy. If proper
`attention is given to the concentration of the drug as well as to the total
`dosage used, intralesional steroids are safe and highly effective in severe
`nodulocystic acne.
`Since inflammatory lesions develop in closed comedones and closed
`comedones are removed during acne surgery, this form of therapy can be
`considered to have an anti-inflammatory effect.
`
`OTHER ACNE-LIKE DISEASES
`
`Acne Conglobata
`
`Acne conglobata is generally considered a separate entity from acne
`vulgaris because of its occurrence at a later period and its chronic,
`unremitting course. Patients with acne conglobata have a mixture of
`comedones, papules, pustules, nodules, abscesses, cysts, and scars on the
`back, buttocks, chest, and, to a lesser extent, the abdomen, shoulders,
`neck, face, upper arms, and thighs. The comedones often have multiple
`openings. The inflammatory lesions are large, tender, and dusky colored,
`and they discharge a foul-smelling serous, purulent, or mucoid material.
`Subcutaneous dissection with the formation of multichanneled sinus tracts
`is common. Healing results in depressed or keloidal scars.
`While some lesions may be sterile or show only the presence of resident
`coagulase-negative staphylococci and anaerobic diphtheroids, it is common
`to isolate coagulase-positive staphylococci. Occasionally, I$-hemolytic strep-
`tococci are found. The presence of a chronic infection may be reflected by
`the presence of a normochromic, normocytic anemia, an elevated white
`blood count with an increased percentage of neutrophils, and an increased
`
`15 of 18
`
`

`

`208 Disorders of the Epidermal Appendages
`
`sedimentation rate. There is no evidence that these patients have decreased
`gamma globulins, and the gamma globulins may even be elevated. The
`fasting blood sugar and glucose tolerance tests are usually normal.
`Since lesions may occur in the axillary and inguinal regions, the disease
`may resemble hidradenitis suppurativa. In fact, the latter disease has been
`considered to form part of a triad with dissecting perifolliculitis of the
`scalp. It would appear, however, that these are separate entities, especially
`since both dissecting perifolliculitis of the scalp and hidradenitis suppur-
`ativa may occur alone.
`The management of these patients is a very difficult problem, and even
`if there is improvement, it often is temporary. Therapy with the appropriate
`systemic antibiotic as determined by in vitro sensitivity studies is indicated,
`as are injections of corticosteroids directly in the lesions on frequent
`occasions. Systemic corticosteroids are useful; however, recurrence of the
`disease is common when they are discontinued. Surgical debridement,
`surgical incision, and surgical excision are also useful adjuncts to therapy,
`although the extent of involvement may make this an overwhelming task.
`The oral retinoids often are of use in these patients, but the precautions
`about their use, discussed earlier in this chapter, should be observed.
`
`Miscellaneous Acne-like Diseases
`
`In addition to the types of acne described above, there are other
`miscellaneous acneform disorders. Ache can be seen in newborns as a
`result of stimulation of the sebaceous glands in utero. Adrenocorticosteroids
`may induce acne, which often is very prominent on the back and chest.
`In contrast to acne vulgaris, comedones are almost always absent and the
`lesions are all papulopustular. Other drugs that may produce acne are
`halogens, isonicotinic acid, diphenylhydantoin, and lithium carbonate.
`Ache may occur from industrial exposure to coal tar derivatives, cutting
`oils, and chlorinated hydrocarbons. A highly inflammatory, severe form
`of acne, similar to acne conglobata, may be seen particularly on the trunk
`in individuals living in the tropics. Ache can be produced by certain
`cosmetics and pomades, from overwashing, and from repetitive rubbing
`(e.g., from a chin strap of a football helmet).
`
`Rosacea
`
`Rosacea is a chronic disorder of the face in middle-aged and older
`persons, characterized by a vascular component (erythema and telangiec-
`tases), with or without an acneform component (papules, pustules,
`nodules). The onset of rosacea is insidious; most patients cannot state
`when it started. Initially, there is transient vascular dilatation with varying
`erythema. Prima