Dermatology, the essentials of cutaneous medicine

Front matter

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A *

V

Preface

In spite of otherwise great excellence, works on dermatology usually ignore the teaching needs of beginners. Cutaneous medicine is so confusing that, unless its study is gradually led up to, it appears chaotic. Indeed, frankness compels the admission that it is never quite simple, even to an accredited expert. Another reference book would have no justification. But this volume aims to present essentials succinctly, consecutively, completely and simply, without sacrificing important detail. Thus, in spirit, it is dedicated to the novice and to the general practitioner, too busy to grapple with technicalities and abstractions. This group of readers should not be burdened with literary citations that cannot possibly interest them; nor with histological descriptions which, unless exhaustive and technical, are valueless, and in any case incomprehensible except to pathologists; nor with elaborate historical sketches that are mainly exhibitions of pedantry. Accordingly, matter of this sort, unless of peculiar practical importance has been omitted since it would add to bulk rather than strength.

Nothing germane has been sacrificed. What remains represents the author's conception of the minimum requisite for an adequate outline of the subject. Less important diseases appear in finer type, not to create an impression that they may be slurred, but to convey graphically their relative place among dermatoses. And to the practitioner also this arrangement will be welcome, for he will find the kernel without himself having to do the husking. Numerous tables have been compiled classifying diseases, their etiology and relationship, always with the combined idea of constructiveness and analysis. There is no excess of illustrations, but the pictures have been selected purely for their didactic value, and the points they purpose to clarify are categorically enumerated. Thus, although in number they do not compare with what is found in many other books, if properly used, they will prove adequate to the requirements of readers seeking a clear-cut impression of the ground work of dermatology. There are about four hundred more or less distinctly established skin conditions, and the beginner or general practitioner is probably not intimately concerned with more than one-quarter of

vii viii PREFACE

them. It is the smaller fraction that is accompanied by pictures, although the rest too are fully discussed in the text.

The subject has been handled, so far as practicable, from the standpoint of internal medicine. The etiology of skin diseases, as a whole, is not yet well understood. Xevertheless, it is obvious that the integument is not autonomous, and that it is greatly influenced by, and greatly influences, the rest of the body. Premature and tentative as must be beliefs connected with this interrelation, it is high time that they were stated, either to be sustained or overthrown in the future. They are set forth in this book, but our knowledge does not yet permit a classification of dermatoses solely on etiological grounds.

Xomenclature in dermatology is discouraging, involved and often unsound. Some terms, however fanciful, have become permanent. Lichen is an example of this. Since its ancient symbolism connotates something definite, there is no reason to assail it. Not so the word eczema ! The disease thus styled is one with vesicular dermatitis in aspect, causation, histology and course. Therefore, the sounder term should replace it. The word is nowhere independently employed in this book, but is used parenthetically after the expression dermatitis, wherever the latter appears. This compromise seemed expedient, for the undesirable term, not yet having been abandoned, must be continued until opinion becomes unanimous as to its further restriction. Scientifically, there is nothing to be said for the word eczema. We speak of occupational dermatitis and occupational eczema, of seborrhoeal dermatitis and seborrhoeal eczema, of fungus dermatitis and fungus eczema, of dermatitis of unknown origin and eczema of unknown origin, etc., always meaning in each couple the identical thing. This is a handicap, particularly since dermatitis, being philologically and medically an accurate designation, is preferable ; and such writers as Gorman Walker, and Pusey have accepted the fact. Another complex subject is cutaneous tuberculosis. Here again there has been a plethora of verbiage. So far as possible an effort has been made at simplification. Congenital syphilis, too, is masked by a literary smoke screen, partly through the inaccurate interpretation of the term hereditary, partly through a series of superstitions that still sustain about a comparatively simple thing an artificial cloud of obscurity. With the utmost respect for venerable traditions, it has been attempted to divest a difficult field of medicine of unnecessary encumbrances.

As to therapy, the author has described only what has commended itself to him through personal experience. As knowledge grows

PREFACE

IX of the cause of, or of the relation of skin to general disturbances, treatment has become both simpler and better. This fact, and the precise accomplishments possible through the use of mechanical agents, such as the X-Rays, carbon dioxide snow and the like, indicate that in extensiveness the dermatological materia medica will shrink as therapy becomes more accurate. Treatment, symptomatology, differential diagnosis, and the significance of skin lesions in their relation to morbid biology are the really important considerations. These constitute the theme of this book. It is hoped that students who seek a rational exposition of the essentials of cutaneous medicine will here find their requirements satisfied. The true dermatologist is an internist who knows the skin.

The photographs appearing in this volume come from the collections of Dr. John A. Fordyce and Dr. George M. Mackee whom it is a great pleasure to thank for them. A similar expression of gratitude is extended to Dr. Jeffrey C. Michael for his valuable aid and suggestions.

W. J. H.

New York, K Y.

Contents

SECTION A. GENERAL CONSIDERATIONS

CHAPTER PAGE

I The Etiology of Skin Diseases 3

Chapter I The Etiology Of Skin Diseases

By far the most important "branch of the science of dermatology is the study of the causation of skin diseases. Upon definite knowledge of etiology alone depends rational treatment ; and in the care of dermatoses, as in all other diseases, only rational treatment can be successful. The struggle to classify disease, to increase precision in diagnosis, to recognize new diseases, has so engrossed scientists that the cure, the one thing of interest to patients, has by comparison been neglected. This is more emphatically true of dermatology than of most other subdivisions of internal medicine. Since the time of the great Viennese, Hebra, until recently, dermatologists have bent their efforts in the direction of classifying and arranging dermatoses mainly according to their clinical appearance. Thus there has developed among dermatologists a slavish attentiveness to the minutest details of skin manifestations in the hope that by constant and further analysis of the lesions, their grouping and color, etc., a satisfactory classification or understanding of the diseases might be reached. This has engendered among dermatologists unthinkably keen powers of observation, and in dermatology excessive refinement as to the characteristic features upon the basis of which similar diseases are differentiated one from the other.

The index to a work on dermatology thus is long, it would seem, to the point of attenuation, and to the medical student or to any reader who is not a dermatologist, both index and pages must appear almost chaotic. Nor can it be stated that the matter is entirely simple even for the specialist. The number of dermatoses recognized as clinical entities is enormous, and will so remain even after our criteria become more settled. We have already ceased to regard eczema of the axillae, scalp, face, body, genitalia, legs et cetera, and weeping, scaling and lichenified eczema as different diseases, although there was a day when this disease, and many others, were subdivided in the manner above outlined, and when each subdivision was regarded as a clinical entity. The most casual accident of appearance or localization was in itself considered sufficient for the creation of another skin disease. The disease was frequently designated in the tongue of the original observer, but more frequently still in Latin or Greek, or an unwholesome blend of both, and usually the name of the author was appended with a Latin genitive ending. These matters are mentioned to account for many of the avoidable sources of confusion in dermatology. A name is but a symbol, and just as every physician knows what Bright' s disease is, or hip disease, or a cold, although none of these designations is good, so every dermatologist must accommodate himself to the disadvantages of such names as white-spot disease, lichen planus, eczema, pityriasis rosea; for if these names were to be changed, either the entire dermatological literature would have to be re-written, or discarded and re-commenced.

Neither of these two possibilities is practicable, so that it remains to revise our ideas on dermatoses partly with regard to their pathology, but more especially with regard to their causation. Hebra and his pupil, Kaposi, of Vienna, dominated dermatology during the last two decades of the past century, and their philosophy reduced to its lowest terms was one in which the integument was considered an organ largely dissociated from the tissues which it enveloped. They tended to regard all dermatoses as peculiar to the skin. This is all the more astonishing in view of the fact that it was Hebra who discovered the use of arsenic in one form of lichen, thus converting the latter from a serious to a mild disease. How one so astute as Hebra could at once maintain the doctrine of the independence of the skin from the rest of the body and attempt to cure a disease essentially restricted to the skin by internal medication is inexplicable. It is equally difficult to grasp why with so patent an illustration of the internal origin of dermatoses as in lichen, he failed to perceive its significance, and thus failed to try to clear up the origin of such diseases as psoriasis and many of the eczemas. But Hebra lived in a day in which the study of micro-organisms was engaging the world, and in which they were being held accountable for all diseases. Hebra was not a good bacteriologist, and he was an even worse histologist, although he sensed the importance of this subject, and referred for study to his former master, Eokitansky, all dermatological questions within this field. The bearing of biochemistry on dermatology was not even thought of in Hebra's time,

THE ETIOLOGY OF SKIN DISEASES 5

and questions included in serology and studies in anaphylaxis which to-day are engaging us, were then, of course, unknown.

It must be remembered, however, that while the Teutons were endeavoring to restrict all dermatoses to the skin, the French had, for nearly a century, been approaching the problem by another avenue. As early as 1777 Lorry, in his " Tractatus de Mortis Cutaneis" under the Hellenic influence of the humoral causation of disease, sought to explain the etiology of many skin diseases by " arthritism." Alibert and Rayer actually tried to classify dermatoses on a basis of their internal causation. The Frankish tendency to correlate all given effects with definite causes, and to find for each an antidote or specific, led the Parisians and their followers far afield. Thus, while the Germans were cataloging dermatoses without reasoning backwards from them, the French were studying etiology without reasoning forwards. Until within recently the two extremes failed to meet. Then a few deductive thinkers endeavored to co-ordinate cause and effect, and a new era in dermatology began to dawn.

In 1839 Schoenlein discovered the fungus which produces favus. In 1853 Gruby rediscovered the microsporon, which had been found by Audouin, and which causes a certain variety of ring-worm, while Eichstedt found the exciting agent of pityriasis versicolor, the microsporon furfur; and Barensprung that of erythrasma, the microsporon minutissimum. The significance of these discoveries was not realized until many years had elapsed when Pasteur and Lister revivified the study of bacteriology. During the last quarter of the Nineteenth Century this science was being ardently pursued, while that of histopathology was being quite as ardently developed. As regards bacteriology, enthusiasts sought to explain all diseases by the activity of microscopic agents, and the pendulum swung too far. Thus Darier regarded psorosperms, which were later found to be epithelial cell degenerations, as the organisms which caused the disease named after him ; Lustgarten isolated the bacillus which he held responsible for syphilis; Unna described a bacillus which he maintained to be the cause of acne. Unna was, however, the pioneer in cutaneous histopathology, and under his influence this science began to flourish.

It is probable that the history of any branch of internal medicine would resemble that of dermatology. The clinical study of this subject is actually the macroscopic pathology of the skin. Its microscopic pathology bears the same relation to the dermatoses that the microscopic appearance of any lesion anywhere in the body bears to its gross appearance. To a certain extent the etiology of disease may be illuminated by an understanding of its microscopic composition. To a larger extent, however, the etiology may be explained through the medium of bacteriology, biochemistry and serology in its broadest sense. A diagnosis should not merely be equivalent to labelling a disease, but should explain, subject to the limitations of human knowledge, its cause. Nothing may be neglected within the scope of physical diagnosis, laboratory diagnosis, or a knowledge of the course and character of illnesses, which furthers this end. Thus, a dermatologist must be equally a clinician, and a student of the significance of laboratory procedure, if not actually a trained laboratory worker. Only then may he aspire to be an intelligent and successful therapeutist. In other words, dermatology is not a science mi generis, but a branch of internal medicine with all that this concept implies.

Every organ, not excepting the skin, is subject to two large groups of morbid processes, those peculiar to itself, and those which include it in the course of systemic disease. The former are autochthonous ; the latter are due to the participation of the given organ in the general pathological reaction of the body. In the second group the local reaction is modified by the anatomic and physiologic peculiarities of the given organ. Thus in syphilis, the skin is differently affected from the meninges, although in the pathological changes in both may be found common features. The same is true for example of leukemia, Hodgkin's Disease and tuberculosis. Furthermore, systemic diseases may predispose to skin diseases of an entirely different nature, as diabetes, in which the skin may remain normal, be slightly inflamed, itch more or less, become infected with pus organisms, or become gangrenous. Further illustrations would be superfluous.

Pure diseases of the skin are numerous. Professional dermatoses, erythrasma and ring-worm will serve as examples. Even here, however, the autonomy of the skin is incomplete, for in deep ringworm, a cutaneous disease pure and simple so far as human eye may discern, there is a systemic response. The serum of individuals afflicted with this malady gives specific and group reactions when the Bordet-Gengou test is applied, and the skin of such patients manifests allergic phenomena in the sense of von Pirquet. Not every charwoman develops a dermatitis of the hands, nor every surgeon a bichloride rash; not every human being exposed gets ring-

THE ETIOLOGY OF SKIN DISEASES 7

worm or ivy poisoning. Thus, even in these dermatoses more is required than the mere operation of an external agent. A predisposition on the part of the patient is needed, and the significance of this is the presence of some anatomic, physiologic or metabolic characteristic which favors his liability to an illness to which his brother is not subject.

Thus the distinction between dermatoses considered local and dermatoses which are not, is more one of convenience than one which will withstand the test of fine philosophic analysis. It is nevertheless a distinction of practical value in arranging and classifying skin affections, although more or less arbitrary.

Chapter II Autochthonous Skin Diseases

Autochthonous maladies of the skin are either congenital or acquired. The congenital types are either accidental, that is, peculiar to the newborn individual himself; or hereditary, that is, transmitted from an immediate or remote ancestor to the newborn individual by virtue of some property of the chromosomes of the parental cells. No expressions are more loosely used in medicine than the words hereditary and congenital. Not every condition that is congenital is hereditary, or there would be in nature no such thing as variation, the fundamental requisite for the origin of species. On the other hand, every hereditary characteristic, whether actually present at birth or not, is congenital. If it is not present at birth, but develops after weeks, months, or years, it is an hereditary characteristic evincing itself later in life, the congenital impulse to which has until then been dormant.

Congenital diseases of the skin which are usually not hereditary are nevi. Ichthyosis may be congenital and either hereditary or not hereditary. It may also appear later in life as an hereditary or nonhereditary disease. The determination of this point, not only in ichthyosis but whenever similar questions arise, will depend entirely upon the family history. Keratosis palmaris et plantaris hereditaria is a family disease which is rarely present at birth. The same is true of monilethrix. Acquired dermatoses are caused by physical and chemical agents, vegetable and animal parasites, undiscovered infectious agents, and by the influences of occupation, habit, environment, race, age and sex. Before proceeding with a further discussion of these facts, it may be desirable to present them in tabular form with simple illustrations.

Group 1. Congenital and Hereditary Diseases

Section A. Congenital Diseases J Nevi — Most Forms.

(Not Hereditary) \ Ichthyosis — Some Forms.

f Nevi 1

Section B. Congenital Diseases I I gome Forms

(Hereditary) ] Ic hthyosis J

AUTOCHTHONOUS SKIN DISEASES

Section C. Hereditary or Family- Diseases (Delayed in Appearing)

Ichthyosis — Some Forms.

Epidermolysis Bullosa Hereditaria.

Keratosis Palmaris et Plantaris Hereditaria.

Section A.

1. Light

2. Heat

3. Cold

Group II. Acquired Diseases

Physical Agents.

Sunburn.

X-Eay Burns.

X-Ray Keratoses and Epitheliomata.

Burns whether due to fire, electric sparks, or hot substances.

Frost-bite.

4. Exposure |

5. Pressure 4

Seaman's skin.

Clavus.

Callous.

Section B. Chemical Agents.

All cause vesicular, bullous urticarial or ulcerating dermatoses.

1. Metallic and Non-metallic Elements.

2. Acids and Acid Salts.

3. Alkalis and Alkaline Salts.

'Rhus toxicodendron.

4. Vegetable Poisons -

Poison Oak.

Primrose.

Nettles.

5. Vegetable and Mineral Oils and

Tars (Tar Acne).

f Mineral.

6. Dyes -j Vegetable.

[ Aniline.

Section C. Vegetable Parasites. 1. Bacteria

A. Cocci, Streptococci

Staphylococci < B. Bacilli |

Impetigo contagiosa.

Erysipelas.

Erysipeloid.

Folliculitis.

Furunculosis.

Tubercle bacillus — T.B. verrucosa cutis.

Klebs-Loeffler bacillus — Impetigines.

2. Fungi

Commonest examples, pityriasis versicolor (microsporon furfur) and various types of ringworm, favus, etc.

Section D. Animal Parasites.

1. Protozoa j Oriental boil.

2. Closely related to protozoa, or protista, Spirochaeta causing verruca Peruana, not to be confused with Oroya fever, which is a systemic disease caused by a bacillus.

Pediculosis.

3. Insects, etc.

Scabies.

Stings of bees, mosquitoes, wasps, bed-bugs, larva migrans.

4. Jelly fish. j Wheals.

5. Vermes <

Leech-bite. Anal eczema from thread worms, etc.

Section E. Undiscovered Infectious Agents

^ -».- n . Recently Wile has discovered a

1. Mollscum contagiosum. «,, ,, „ ,

2. Verruca plana. 1 * ltrable 7 1 ™ capable of pro "

L ducmg these lesions.

Section F. Occupation.

Surgeons, nurses, orderlies, charwomen, employees in slaughter houses, factories, etc., are prone to develop a great number of dermatoses, mostly on the hands. The immediate causes of these diseases are such physical or chemical agents as are peculiar to their particular work. See Group II., Section A., 1-5; and Section B., 1, 2, 3, 5 and 6.

Section G. Habit.

Habit and occupation are closely related. The manner of holding tools and utensils may determine the location of callouses or injuries on the hands. Inadvertent mannerisms, such as scratching, nail biting, biting of the cuticle will determine corresponding injuries. Hysterical and designing individuals inflict upon themselves injuries by divers methods and means.

Section E. Environment.

Inmates of institutions, children at schools, people living crowdedly in filth, are exposed to infections caused both by animal and vegetable parasites. Geographical considerations, too, should be included under this heading. Thus, piedra is a fungus disease of the South (in the region of Panama) ; verruca Peruana is found only in a certain district of the Andes ; Oriental boil is peculiar to countries on the Northeastern and Southern shores of the Mediterranean and Southern Asia.

AUTOCHTHONOUS SKIN DISEASES 11

Section I. Race

Negroes are peculiarly predisposed to keloids. Madura foot, caused by an organism closely related to the ray-fungus, is more frequent among natives of India and Africa than among aliens. Section J. Age.

Certain types of ring-worm, molluscum contagiosum and verruca plana are rare, except in childhood. A characteristic type of wart known as senile hyperkeratosis is restricted to the period of life its name suggests.

Section K. Sex.

The two sexes present about the same series of dermatoses. Such variations as the lesions may show are due rather to anatomical peculiarities than to any inherent sex differences.

Kace, age and sex are minor considerations in their etiological relation to pure dermatoses, as compared with the rest of the foregoing table. Study of this table will also show a high degree of interdependence among the various factors. For instance, diseases of occupation (Section F) depend directly upon their causation for some chemical agents (Section B) and some physical agents (Section A) and infectious agents (Section D). Diseases are due to environment (Section H) only in a passive and subsidiary sense, for it is due to the environment that the infectious or other active agents (Sections C, D and E) gain access to their host. It is important, too, to bear in mind the fact that not every worker exposed to given chemical, physical, or other pathogenic influences, nor every child exposed to ring-worm or pediculi, becomes diseased. As already stated (Chapter I), the patient must be receptive to the disease which the pathogenic agent is capable of producing. Whether this predisposition is due to race, age, sex, occupation, environment, individual peculiarity, or a combination of these makes no difference, and in so far as this is true there are very few pure skin diseases. For practical purposes, however, it is simpler to accept the existence of such a group, although by no means in the restricted and isolated sense it has heretofore possessed.

Chapter III Skin Diseases Which Are Not Autochthonous

RELATION OF DERMATOLOGY TO INTERNAL MEDICINE

Although, as has been indicated, the line of demarcation is no sharp one between skin diseases which may for convenience be termed local, and those which in no sense may be so termed, the relationship of the second group to internal medicine is not entirely clean-cut. Psoriasis, for example, lichen planus, prurigo, pemphigus and dermatitis herpetiformis are more emphatically characterized by their cutaneous manifestations than by any general symptoms they cause, or with which they are associated. It is nevertheless impossible to be familiar with these diseases and many others without becoming convinced that the part the skin plays in them, though conspicuous, is incidental, and that their causation must be sought elsewhere than in the integument. It is possible that any or all of these diseases may be due either to specific skin parasites, operating locally, to a specific internal infection which causes definite cutaneous changes, or to some metabolic or biochemic disturbance giving rise to characteristic alterations in the skin. Even admitting the likelihood of a specific local infection in these diseases, their course is such as to suggest that some internal disturbance is required to fertilize the soil for the local agent, in which case the local factor after all becomes the incidental one.

There are, indeed, not many ways in which the skin may be pathologically altered, so that many processes which are widely separated as to their origin may be characterized by like or closely allied cutaneous manifestations. Both urticaria and dermatitis aptly illustrate this. The wheals of urticaria are all alike. The causes of urticaria are numerous. The flesh of fish, Crustacea, beef, molluscs, egg albumin, strawberries, alien serum, and many other substances, known and unknown, in receptive individuals cause urticaria. The disease is simple to recognize, but its cause in given cases is usually difficult to ascertain. Acute and chronic dermatitis, a vesicular and scaling disease, may be provoked by rhus, primroses, bichloride, dye-stuffs, vanilla, essential oils, wood oils, pollens, many varieties of chemicals, and by a host of internal causes. ]STor can dermatitis be clinically or histologically differentiated from eczema. Here again the problem is to discover the ultimate cause of the disease, that is,

SKIN DISEASES WHICH ABE NOT AUTOCHTHONOUS 13

to find out what the interrelationship is between the skin and the rest of the body.

Skin lesions primarily or secondarily due to an internal cause are called cutaneous reactions. Thus, the urticarial wheal; the vesicle of acute eczema or dermatitis; the erythematous blotches caused by copaiba, antipyrin or phenacetin, ptomaines, bacteria or their toxins ; the scarlatinif orm rash of scarlet fever, or belladonna poisoning; the herpetic vesicles of true herpes, or associated with arsenic poisoning or grippe — all respectively are examples of types of cutaneous reactions, similar in appearance but due to a wide variety of causes.

Diseases of the skin which are not local are either those in which the skin participates in a systemic disease, or those in which a disease, beginning in the skin, becomes systemic. The only real difference between the two is one of sequence, for in the second group the skin is the starting point of the malady, instead of being merely a participant. Extensive burns and infectious diseases such as erysipelas, syphilis, glanders and anthrax are illustrations. It must by now be clear that the physiologic and metabolic balance of the human organism is shared to no small degree by the skin, and that the part played by internal medicine in dermatology is large. But this interrelationship is no simple one to trace. A classification of dermatoses from this standpoint is difficult to compose, and roughly parallels that in the preceding chapters. The following list though not complete, suggests by common examples the scope of the field under discussion.

Section A,

Section B.

Section C.

Section A.

Group I. Congenital and Hereditary Diseases

Congenital Diseases (Not Hereditary)

Cogenital Diseases (Hereditary)

Syphilis.

Icterus neonatorum.

Some types of hemophilia.

Hereditary or Family Diseases. (Not Congenital)

Xeroderma pigmentosum.

Hemophilia.

1. Erythemas

Group II. Acquired Diseases

Chemicals and Drugs.

Belladonna.

Copaiba.

Many of the coal tar products.

Arsenic

2. Vesicles and Bullae

3. Pustules

4. Wheals j

5. Granulomata J

6. Pigmentation

7. Epithelial proliferation

Arsenic

Bromides.

Iodides.

Iodides.

Bromides.

Quinin, the balsams, sera, antitoxins, vaccines.

Iodides.

Bromides.

Arsenic.

\ Arsenic.

Section B. Vegetable Parasites.

1. Bacteria

2. Bacterial Toxins

3. Fungi.

Lepra, Lupus vulgaris and other forms of cutaneous tuberculosis, blennorrhagic granuloma, glanders anthrax, typhoid roseola, typhus roseola, various eruptions associated with erythema nodosum and sepsis.

Toxi-tubereulides, toxins of streptococci and staphylococci in sepsis, accompanying angina of streptococcus origin causing some varieties of multiform erythema, and allied diseases.

Actinomycosis sporotrichosis.

blastomycosis,

Section C. Animal Parasites.

1. Protozoa or Organisms closelvf allied 1

2. Vermes

Syphilis.

Yaws.

Urticaria accompanying echinococcus and other parasitic infections.

Section D. Undetermined Infections — The Acute Exanthemata:

Scarlet, measles, chicken and small pox, German measles, Duke's disease; probably some forms of erythema multiforme, and possibly pityriasis rosea.

Section E. Toxins — Anaphylatoxins. 1. Anaphylatoxins

Urticaria and probably some forms of dermatitis; prurigo.

SKIN DISEASES WHICH ARE NOT AUTOCHTHONOUS 15 a. Disturbed nitrogen metabolism

2. Toxins expressing faulty metabolism.

Some dermatitis, dermatitis herpetiformis, and Hitters' dermatitis; forms of infantile dermatitis; Leiner's erythroderma desquamativa congenita.

Diabetic dermatitis, carbuncle, furunculosis, gangrene.

Hyperglycemia, diseases of the pilosebaceous system, sycosis, rosacea, furunculosis, acne, seborrhoea and seborrhoeal dermatitis, some forms of infantile dermatitis.

b. Disturbed sugar metabolism c. Disturbed fat and cholesterin J metabolism \

3. Gastro-intestinal indigestion.

a. Gastric hyperacidity, chronic] gastritis, athylia gastrica, etc.]

b. Carbohydrate fermentation.

See Section E. 3, a.

c. Disturbed pancreatic and liver function.

See Section E. 3, a.

d. Proteid putrifaction associated

with disturbed nitrogen metabolism, or changed permeability of gut, allowing of absorption of anaphylatoxins or other toxins. See Section E., 3, a.

4. Eenal disturbance, part of dis-

turbed nitrogen or sugar metabolism.

Infantile dermatitis, xanthoma tuberosum.

Acne, rosacea, seborrhoea, closely allied to disturbed sugar metabolism.

Section F. Disturbances of Internal Secretion

Skin

1. Thyroid.

2. Adrenals and Chromaffinic System.

changes in cretinism, Graves' disease; effect of thyroid on sugar metabolism through pancreas and liver.

See Section E., 2, b.

Pigmentation, Addison's disease, bronzed diabetes; possibly vitiligo.

3. Pituitary Body.

Skin disturbances in acromegaly, hirsutes and effect of gland upon sugar metabolism.

See Section E., 2, b.

Section G. Disturbances of Primary and Secondary Sexual Organs (possibly of internal secretions).

1. Puberty (both sexes).

2. Menstruation.

3. Pregnancy.

4. Menopause.

Section H. Nervous System. 1. Central.

2. Peripheral.

Acne; in women, hirsutes.

Acne, vaso-motor dermatoses.

Acne, eczema, pruritis, urticaria, vesicular and bullous dermatoses, fibromatosis, hyper-pigmentation, hirsutes.

Dermatitis, rosacea, vaso-motor dermatoses.

Gangrene, herpes, malum perf orans pedis, pellagra, neurotrophic disturbances of syringomyelia, multiple sclerosis, tabes; traumatic alopecia, decubitus, scleroderma.

Pruritus and herpes ; dermatalgia andf possibjly symmetrical gangrene.

Section I. Visceral Malignant Neoplasms.

Cutaneous metastases, acanthosis nigricans, pigmentations.

Section J. Cachexias and Prolonged Fevers.

Dry skin, sudamina, alopecia, nail distrophies, pigmentations, exfoliating erythrodermas, etc.

Section K. Diseases of the Blood, Lymph and Blood and Lymph making Systems.

Leukemic and pseudo-leukemic infiltrations of the skin, premycotic dermatoses, erythrodermas.

In other chapters of this book the outline just sketched in will "be amplified as each disease is discussed. It is the sole object of this chapter to emphasize that dermatology belongs to internal medicine, and that the dermatologist should be less a reservoir of special designations than an internist regarding internal medicine with an

SKIN DISEASES WHICH AEE NOT AUTOCHTHONOUS 17