6th year · Dermatology — Summary sheet

1. Generalities, normal skin and diagnostic approach

The skin is an organ of protection, thermoregulation, immunity, sensitivity, communication and metabolic synthesis. It includes the epidermis, dermis and hypodermis. In dermatology, the diagnosis begins with the morphological description, then the topography, the evolution and context guide etiology.

Interrogation

Acute, chronic or recurrent onset; evolution and triggering factors.
Pruritus, pain, fever, general signs, medication, exposure.
Background: atopy, immunosuppression, pregnancy, age, profession, entourage.
Impact: sleep, quality of life, work, schooling, body image.

Inspection

Basic lesion type, color, shape, boundaries, surface and grouping.
Topography: exposed areas, folds, scalp, nails, mucous membranes, palms, soles.
Extension, symmetry, systemic involvement or signs of infection.
Follow-up photographs and additional examinations according to specialized indication.

4-step approach

Describe the lesion, locate its topography, specify the chronology, then integrate terrain and general signs.

Things to remember

In dermatology, the morphological diagnosis precedes the etiological diagnosis: naming the basic lesion avoids many errors.

Exam trap

Starting with an etiology without describing the lesion leads to confusing eczema, psoriasis, mycosis or infection.

2. Basic lesions in dermatology

Basic lesions are the basic vocabulary: macule, papule, plaque, vesicle, bubble, pustule, nodule, ulceration, scale, crust, erosion, atrophy, lichenification and purpura. Their description must remain precise, sober and non-sensationalist.

Macule vs papule vs plaque vs nodule
Lesion	Definition	Relief	Guidance
Macule	Color change without palpable relief.	Absent.	Dyschromia, erythema, purpura, pigmented lesion.
Papule	Small solid raised lesion.	Present.	Inflammatory, infectious, allergic or tumoral depending on the context.
Plate	Extensive, palpable lesion, often by confluence.	Present.	Psoriasis, chronic eczema, inflammatory dermatosis.
Nodule	Deep or infiltrated solid lesion.	Often firm.	Tumor, deep inflammation, specific infection depending on context.

Vesicle vs bulla vs pustule
Lesion	Content	Size/relief	Guidance Examples
Vesicle	Clear liquid in small collection.	Small raised lesion.	Acute eczema, viral infection, early bullous dermatosis.
Bubble	Clear or cloudy liquid, larger collection.	Localized skin detachment as a clinical concept.	Pemphigus, pemphigoid, possible severe drug reaction.
Pustule	Purulent contents not graphically described.	Inflammatory elevation.	Acne, folliculitis, impetigo, pustular psoriasis depending on context.

Things to remember

Morphological precision makes differential diagnoses much simpler: relief, content, color, surface and topography.

Exam trap

Calling any skin lesion a “pimple” prevents reasoning: papule, pustule, vesicle and nodule do not lead to the same hypotheses.

3. Dermatological therapeutics and topical corticosteroids

Dermatological treatments are based on local care, emollients, antiseptics such as principle, topical corticosteroids, systemic treatments or photoprotection depending on the pathology. This sheet presents the classes, general indications, monitoring and education, without prescriptive detail.

Local care

Gentle cleansing, restoration of the skin barrier, emollients.
Avoid irritants, scratching, inappropriate self-medication and mixing products.
Adapt dosage form to site, lesion and tolerance.

Dermocorticoids

Variable power depending on molecule, zone and indication.
Local adverse effects: atrophy, fragility, pigmentary disorders as principles.
Education: compliance, supervised duration, monitoring and reassessment.

Things to remember

Effective local treatment depends as much on the diagnosis as on the form, site, supervised duration and patient education.

Exam trap

Using a topical corticosteroid without diagnosis can mask an infection or aggravate certain dermatoses.

4. Eczema, atopic dermatitis and contact dermatitis

Eczema combines skin inflammation, pruritus and progressive lesions. It can be acute, chronic, atopic, contact allergic or irritant. Evolution towards lichenification reflects chronic scratching and ringing.

Eczema vs psoriasis vs mycosis
Criterion	Eczema	Psoriasis	Mycosis
Dominant symptom	Pruritus often major.	Variable pruritus, aesthetic and chronic impact.	Variable pruritus, centrifugal or intertrigo extension depending on form.
Lesion	Erythema, vesicles as principle, possible oozing, then lichenification.	Well-defined erythematous-scaly plaques.	Active border, scales, involvement of folds, nails or scalp depending on germ.
Topography	Folds, children's face, contact areas or irritants.	Elbows, knees, scalp, lower back, nails.	Folds, feet, nails, scalp, damp areas.
Trap	Confusing mycosis and chronic eczema.	Forget psoriatic arthritis.	Worsened by inappropriate local treatment.

Atopic dermatitis vs contact dermatitis
Criterion	Atopic dermatitis	Contact dermatitis
Land	Personal or familial atopy, dry skin, flare-ups.	Exposure to allergen or irritant, professional or domestic context.
Distribution	Topography varies according to age, often folds in older children.	Zone of contact or exposure, sometimes secondary extension.
Diagnosis	Clinical, chronic, recurrent, impact of pruritus.	Exposure interrogation, allergological tests as a principle if indicated.
Care	Emollients, local anti-inflammatories according to indication, education.	Avoidance of the agent, protection, management of inflammation.

Things to remember

Eczema = pruritus + inflammation + progression by flare-ups; the topography and exposure are atopic, contact or irritative.

Exam trap

A pruritic scaly lesion is not always eczema: mycosis and psoriasis must be discussed.

5. Psoriasis, lichen and inflammatory dermatoses

Psoriasis is a chronic inflammatory dermatosis with erythematous-scaly plaques, classic locations, possible nail involvement and psoriatic arthritis such as association. Lichen planus is an inflammatory dermatosis to be aware of as a differential diagnosis.

Skin psoriasis vs psoriatic arthritis
Criterion	Skin psoriasis	Psoriatic arthritis
Reached	Skin patches, scales, nails, scalp, folds depending on shape.	Peripheral joints, spine, entheses or dactylitis as principles.
Call signs	Recurrences, triggering factors, impact on quality of life.	Inflammatory joint pain, stiffness, swelling, heel pain.
Issue	Control inflammation, pruritus, visibility and chronicity.	Prevent joint destruction and disability.
Trap	Limit yourself to the skin.	Do not question joint pain in a psoriatic patient.

Factors and impact

Possible triggering factors: stress, infections, medications, skin trauma as principles.
Nail damage can lead to joint risk.
General care combines education, local or systemic treatments depending on severity and specialized monitoring.

Things to remember

Any psoriasis should be investigated for nail damage and inflammatory joint pain.

Exam trap

Inverted psoriasis in the folds can mimic a fungal infection or contact eczema.

6. Acne, pyoderma and bacterial skin infections

Bacterial skin infections often involve staphylococci or streptococci. They range from impetigo or folliculitis to erysipelas and infectious cellulitis such as clinical principles. The general signs and the extension determine the urgency.

Acne vs folliculitis vs impetigo
Criterion	Acne	Folliculitis	Impetigo
Mechanism	Involvement of the pilosebaceous follicle with inflammation.	Inflammation or infection of the hair follicle.	Contagious superficial skin infection.
Lesions	Comedones, papules, pustules, nodules depending on severity.	Pustules centered by a follicle.	Erosions or crusts as a non-graphic clinical presentation.
Land	Adolescent or adult, possible psychological impact.	Rubbing, shaving, humidity, immunosuppression.	Child, community, contagiousness.
Trap	Minimize psychosocial impact.	Confused with acne or follicular mycosis.	Forget hygiene measures and collective context.

Erysipelas vs infectious cellulitis
Criterion	Erysipelas	Infectious cellulitis
Reached	Acute dermal infection, often well limited.	Deeper or diffuse infection of the skin and subcutaneous tissues.
Signs	Redness, heat, pain, possible fever.	Pain, extension, edema, general signs sometimes marked.
Severity	Fragile ground, recurrence, gateway, extension.	Disproportionate pain, general deterioration, immunosuppression, rapid spread.
Guidance	Clinical evaluation, prevention of recurrences.	Urgent referral if severity or doubt about deep infection.

Signs of severity

Fever, general deterioration, disproportionate pain, rapid spread or immunosuppression require urgent evaluation.

Things to remember

In a skin infection, terrain, speed of extension, pain and general signs take precedence over the local aspect alone.

Exam trap

An extensive skin infection in immunocompromised patients can be serious despite an unspectacular initial presentation.

7. Superficial mycosis and ringworm

Superficial mycoses include dermatophytes, mucocutaneous candidiasis such as principle, pityriasis versicolor, ringworm, mycotic intertrigos and onychomycosis. The diagnosis is clinical and sometimes mycological, especially before long treatment or atypical form.

Dermatophytia vs candidiasis vs pityriasis versicolor
Criterion	Dermatophytia	Candidiasis	Pityriasis versicolor
Headquarters	Hairless skin, feet, nails, scalp depending on shape.	Folds, mucous membranes, damp or macerated areas.	Trunk and root of limbs, fine dyschromia.
Appearance	Annular or scaly lesion, active border possible.	Fold erythema, fissuring or satellite lesions as sober principles.	Finely scaly hypo- or hyperpigmented macules.
Factors	Contact, humidity, sport, animal, community.	Maceration, diabetes, immunosuppression, antibiotic therapy as context.	Heat, sweating, recurrence.
Trap	Confused with eczema or psoriasis.	Forget contributing factor.	Persistence of dyschromia after control of inflammation.

Ringworm and onychomycosis

Ringworm: scalp involvement, child or community context, mycological diagnosis as a principle.
Onychomycosis: nail thickening or dyschromia; confirm if doubt or prolonged treatment planned.
Prevention: drying of folds, suitable shoes, treatment of sources and reassessment of recurrences.

Things to remember

Mycosis, eczema and psoriasis often look alike: active border, topography and mycological examination provide guidance.

Exam trap

Treating a suspected mycosis without confirmation in the face of an atypical or chronic form can delay another diagnosis.

8. Ectoparasitoses: scabies and pediculosis

Scabies and pediculosis are contagious, often familial or collective. Pruritus, evocative locations and context guide the diagnosis. Collective measures and prevention of recidivism are as important as individual treatment.

Scabies vs pediculosis
Criterion	Scabies	Pediculosis
Agent	Contagious cutaneous ectoparasitosis.	Lice infestation depending on location.
Clinic	Pruritus often nocturnal, family context, suggestive locations.	Localized pruritus, nits or visible parasites according to examination.
Context	Family, community, promiscuity, recidivism if contacts not taken into account.	School, family, community, sharing of objects according to form.
Measurements	Contact treatment and linen as collective principles.	Treatment and prevention of reinfestations as principles.

Things to remember

In ectoparasitosis, the diagnosis is individual but treatment is based on contacts.

Exam trap

Treating only the index patient explains many apparent recurrences.

9. STIs, syphilis, genital ulcers and urethritis

STIs in dermatology can be revealed by genital ulceration, urethritis, rash, condyloma as principle or general signs. The diagnostic formulation remains strictly medical, sober and not explicit. Screening and taking partners into account are matters of public health.

Syphilis vs. other genital ulcers
Criterion	Syphilis	Other genital ulcers
Presentation	Possible genital ulceration, sometimes associated with lymphadenopathy, then secondary manifestations.	Infectious, inflammatory, traumatic or tumor ulcerations as differential diagnoses.
Diagnosis	Serology and STI assessment depending on context.	Clinical examination, specialized samples if indicated, search for severity factors.
Issue	Screening, appropriate treatment, prevention of transmission and complications.	Do not trivialize a persistent or atypical lesion.
Trap	Presentation sometimes discreet or spontaneously regressive.	Confusing all ulcerations with a single etiology.

Things to remember

Genital ulceration = etiological diagnosis, STI screening and prevention of complications, with sober medical language.

Exam trap

A lesion that disappears does not mean the absence of syphilis; the reasoning is based on chronology and screening.

10. Cutaneous leishmaniasis, cutaneous tuberculosis and specific infections

Specific infections are discussed in the face of chronic lesions, epidemiological context, exposure, immunosuppression or failure of habitual reasoning. The diagnosis is based on clinical examination and parasitological or microbiological confirmation depending on the specialized context.

Cutaneous leishmaniasis vs. cutaneous tuberculosis
Criterion	Cutaneous leishmaniasis	Cutaneous tuberculosis
Context	Endemic area, vector exposure, chronic lesion.	Tuberculosis context, immunosuppression, atypical chronic disease.
Presentation	Chronic localized lesion as a sober clinical principle.	Varied skin forms, slow or recurrent progression.
Diagnosis	Parasitological or specialized confirmation depending on context.	Microbiology, histology as a principle and imaging according to signs.
Differential	Chronic ulcer, tumor, bacterial infection or deep mycosis.	Leishmaniasis, atypical mycobacteria, tumor, vasculitis.

Things to remember

A chronic lesion in an endemic area or with a tuberculosis context should lead us away from banal dermatological reasoning.

Exam trap

Repeating local treatments for a chronic lesion without reconsidering the diagnosis delays specialist referral.

11. Urticaria, pruritus, prurigo and skin allergies

Urticaria manifests itself as fleeting itchy lesions; it can be acute or chronic. Pruritus can be dermatological, systemic, medicinal or psychogenic as a principle. Angioedema is a warning sign depending on location and impact.

Acute urticaria vs. chronic urticaria vs. angioedema
Criterion	Acute urticaria	Chronic urticaria	Angioedema
Duration	Recent episode, often triggered by infection, food, medication or context.	Recurrent or persistent over the long term.	Deep edema, sometimes associated with urticaria or isolated.
Clinic	Fleeting itchy plaques, rapid migration.	Recurrences, impact on sleep and quality of life.	Involvement of the face, lips or airways as an alert context.
Assessment	Often clinical, oriented by severity and trigger.	Reasoned assessment, avoid undirected systematic explorations.	Evaluate respiratory and terrain discomfort, urgent referral if there are any repercussions.

Signs of severity

Angioedema with difficulty breathing, malaise, severe mucosal damage or general deterioration requires urgent referral.

Things to remember

The fleeting and migratory nature of the lesions helps to recognize urticaria.

Exam trap

Generalized pruritus without primary lesion should lead to a search for a general or medicinal cause.

12. Bullous dermatoses and eruptive fevers

Autoimmune bullous dermatoses include pemphigus and bullous pemphigoid like principles. Eruptive fevers and infectious exanthems are interpreted according to age, terrain, fever, general signs, mucosal damage and extension.

Pemphigus vs bullous pemphigoid
Criterion	Pemphigus	Bullous pemphigoid
Mechanism	Intraepidermal autoimmune bullous dermatosis as a principle.	Subepidermal autoimmune bullous dermatosis as a principle.
Land	Adult, possible and significant mucosal damage.	Elderly subject frequent, pruritus and tense bubbles as principle.
Severity	Mucosal damage, extension, general alteration.	Fragility of the terrain, superinfection, undernutrition or impact.
Diagnosis	Clinical, immunology and histology as specialized principles.	Clinical, immunology and histology as specialized principles.

Signs of severity

Extensive bubbles, severe mucosal damage, fever, fragile terrain or associated ocular damage require urgent referral.

Things to remember

A bullous dermatosis is analyzed by terrain, bubble tension, mucous membranes, extension and general signs.

Exam trap

Do not trivialize a bullous rash in an elderly person or one with mucosal involvement.

13. Skin tumors: carcinomas and melanoma

Skin tumors include basal cell carcinoma, squamous cell carcinoma and melanoma. Risk factors include sun exposure, phototype, immunosuppression and background. Any rapidly progressive pigmented lesion or atypical persistent lesion should be evaluated.

Basal cell carcinoma vs squamous cell carcinoma vs melanoma
Criterion	Basal cell carcinoma	Squamous cell carcinoma	Melanoma
Land	Chronic sun exposure, elderly subject, clear phototype.	Precancerous lesions, immunosuppression, sun, chronic wound.	Clear phototype, sunburn, nevus, personal or family history.
Evolution	Slow, local, rarely metastatic.	Local and metastatic risk depending on form.	Significant metastatic potential, crucial early diagnosis.
Warning signs	Persistent, pearly or ulcerated lesion as a sober principle.	Keratotic lesion, ulcerated or bleeding easily as a warning sign.	ABCDE: asymmetry, edges, color, diameter, evolution.
Diagnosis	Histological confirmation as a principle.	Histological confirmation as a principle.	Specialized diagnostic excision and histology as principles.

Prevention and monitoring

Photoprotection, screening of suspicious lesions and monitoring of patients at risk.
A lesion that develops, bleeds, ulcerates or changes in appearance requires specialist advice.
Pathology structures diagnosis and staging.

Signs of severity

Rapidly progressive pigmented lesion, ulceration or bleeding from a suspicious lesion, lymphadenopathy or general deterioration warrant rapid referral.

Things to remember

For melanoma, evolution is the most important criterion: any recent change is suspicious.

Exam trap

Basal cell carcinoma progresses slowly, but a chronic facial lesion should not be trivialized.

14. Leg ulcer, varicose veins and cutaneous vascular pathology

Leg ulcers can be venous, arterial or mixed. The exam looks for pain, pulse, edema, signs of venous insufficiency, arteriopathy, secondary infection as a principle, factors for delayed healing and functional impact.

Venous vs arterial vs mixed ulcer
Criterion	Venous ulcer	Arterial ulcer	Mixed ulcer
Context	Venous insufficiency, varicose veins, edema, thrombotic history.	Arteriopathy, pain on exertion or rest, decreased pulse.	Association of venous and arterial factors.
Pain	Variable, often improved by elevation.	Often more painful, worse by elevation or recumbency depending on context.	Unpredictable pain and scarring.
Assessment	Venous assessment as a principle, research on healing factors.	Priority arterial assessment, vascular assessment.	Complete vascular assessment.
Trap	Forget associated arteriopathy.	Applying inappropriate measures without vascular assessment.	Underestimate the risk of delayed healing.

Things to remember

When faced with a leg ulcer, feel the pulse and consider the vascular assessment before concluding.

Exam trap

A chronic ulcer that does not heal must be re-evaluated: infection, arteriopathy, cancer or inflammatory cause are possible.

15. Alopecia, dyschromia and occupational dermatoses

Alopecia can be diffuse or localized, scarring or non-scarring. Dyschromias include hypopigmentation, hyperpigmentation, vitiligo as principle and melasma as a principle. Occupational dermatoses are dominated by irritative or allergic eczema.

Diffuse vs localized alopecia
Criterion	Diffuse	Localized
Distribution	Global fall or widespread rarefaction.	Limited plates or areas.
Causes	Effluvium, deficiency, endocrine, medication, stress, postpartum as principles.	Alopecia areata, ringworm, traction, scarring alopecia, local trauma.
Review	Traction, scalp, nails, general signs.	Inflammation, scales, scar, broken hair, limits.

Hypopigmentation vs hyperpigmentation
Criterion	Hypopigmentation	Hyperpigmentation
Definition	Reduction in skin coloring.	Increased skin coloring.
Examples	Vitiligo, pityriasis versicolor, inflammatory sequelae.	Melasma, post-inflammatory pigmentation, endocrine or medicinal as principles.
Resonance	Aesthetics, photoprotection, psychological impact.	Aesthetics, search for cause if diffuse or atypical.

Occupational irritative vs allergic dermatosis
Criterion	Irritative	Allergic
Mechanism	Direct alteration of the skin barrier by repeated products or actions.	Contact hypersensitivity to an occupational allergen.
Context	Frequent washing, humidity, solvents, detergents, friction.	Specific exposure, recurrence upon resumption, improvement upon eviction.
Diagnosis	Professional interrogation, chronology, topography.	Allergological tests as a principle if indicated.
Prevention	Protection, emollients, adaptation of the position.	Avoidance or substitution of the allergen, declaration according to framework.

Things to remember

Alopecia, dyschromia and occupational dermatosis have a frequent psychological impact, which must be included in the reasoning.

Exam trap

Localized scaly alopecia in children should suggest ringworm before concluding that it is alopecia areata.

16. Dermatological emergencies and signs of seriousness

Dermatological emergencies are recognized by fever, deterioration of general condition, febrile purpura, extensive bullae, severe mucosal damage, angioedema with discomfort respiratory, extensive infection, skin necrosis as a sober alert or fragile ground.

Land at risk

Immunosuppression, child, pregnancy, elderly, comorbidities, recent medication use.
Eye damage associated with bullous or eruptive dermatosis.
Disproportionate skin pain or rapid expansion.
Febrile rash with mucosal damage or general signs.

Signs of severity

Febrile purpura, extensive bullae, severe mucosal damage, extensive infection or respiratory difficulty require hospital referral.

Things to remember

In dermatology, severity often depends on the site, extension, fever, mucous membranes and general condition.

Exam trap

A recent drug rash with fever or mucosal damage should not be considered a trivial allergy.

Signs of severity to never miss

Major dermatological alerts

Febrile purpura.
Febrile rash with deterioration in general condition.
Severe mucosal damage.
Expanded bubbles.
Disproportionate skin pain.
Skin necrosis as a sober clinical alert.
Angioedema with difficulty breathing.
Extensive skin infection.
Dermatosis in immunocompromised people.
Rapidly progressive pigmented lesion.
Chronic ulcer that does not heal.
Hemorrhage or ulceration of a suspicious tumor lesion.
Suspected severe drug rash.
Generalized pruritus with general signs.
Fever with extensive skin lesion.
Eye damage associated with bullous or eruptive dermatosis.

Express revision in 60 points

Describe the lesion before proposing the etiology.
The skin includes epidermis, dermis and hypodermis.
Macule = color change without relief.
Papule = small solid raised lesion.
Plaque = extensive palpable lesion.
Nodule = deep or infiltrated solid lesion.
Gallbladder = small fluid collection.
Bubble = larger fluid collection.
Pustule = purulent content, to be described soberly.
Scale = detachable horny lamella.
Crust = desiccation of an exudate.
Erosion = superficial loss of substance.
Ulceration = deeper loss of substance.
Purpura does not disappear with vitropressure.
Pruritus eczema, urticaria, parasitosis or general cause.
Dermocorticoids: potency, site and supervised duration matter.
A topical corticosteroid can mask an infection.
Eczema: pruritus and progressive inflammation.
Atopic dermatitis: atopic terrain and dry skin.
Contact dermatitis: exposure and topography.
Allergological tests: principle if allergic dermatitis suspected.
Psoriasis: well-limited erythematous-scaly plaques.
Psoriasis: look for nail damage.
Psoriasis: don't forget psoriatic arthritis.
Acne: pilosebaceous follicle and psychological impact.
Folliculitis: pustule centered by a follicle.
Impetigo: contagious superficial infection.
Erysipelas: acute infection often well limited.
Extensive cellulitis: look for general signs.
Mycosis: topography and active border orient.
Ringworm: think child, scalp, community.
Onychomycosis: confirm if in doubt or long treatment.
Scabies: pruritus, family context, contagiousness.
Pediculosis: localized pruritus and collective context.
Ectoparasitosis: treating collective reasoning.
STIs: medical language, screening and prevention.
Syphilis: sometimes discreet presentation.
Genital ulceration: broad differential diagnosis.
Leishmaniasis: endemic context and chronic lesion.
Cutaneous tuberculosis: atypical chronic course.
Urticaria: fleeting and migratory lesions.
Chronic urticaria: reasoned assessment, not systematic.
Respiratory angioedema = emergency.
Generalized pruritus without lesion: look for general cause.
Pemphigus: possible mucosal damage.
Pemphigoid: common elderly subject.
Extended bubbles = sign of gravity.
Eruptive fever: terrain and mucous membranes guide gravity.
Melanoma: recent development = alert.
ABCDE helps identify a suspicious pigmented lesion.
CBC: often local development but needs to be treated.
Squamous cell carcinoma: possible metastatic risk.
Photoprotection = major dermatological prevention.
Venous ulcer: edema and venous insufficiency.
Arterial ulcer: pain and decreased pulse.
Chronic non-healing ulcer = reassessment.
Diffuse alopecia: look for deficiency, endocrine, medication.
Localized scaly alopecia in children: think ringworm.
Dyschromia: hypo- or hyperpigmentation to be contextualized.
Occupational dermatosis: questioning gestures, products and position.

Glossary

Dermatology: Medical discipline of diseases of the skin, visible mucous membranes, hair and nails.
Elemental Lesion: Basic morphological unit used to describe a dermatosis.
Macule: Color change without palpable relief.
Papule: Small solid raised lesion.
Plate: More extensive palpable lesion, often by confluence.
Vesicle: Small intra- or subepidermal fluid collection.
Bubble: Greater skin fluid collection.
Pustule: Raised lesion containing purulent fluid.
Nodule: Deep or infiltrated solid lesion.
Dander: Horny lamella detaching from the skin surface.
Crust: Drying of a liquid on the surface of the skin.
Ulceration: Loss of skin substance deeper than erosion.
Pruritus: Sensation leading to the need to scratch.
Eczema: Pruritic inflammatory dermatosis, acute or chronic.
Atopic dermatitis: Chronic recurrent eczema linked to atopic conditions.
Contact dermatitis: Skin inflammation caused by allergen or contact irritant.
Psoriasis: Chronic inflammatory dermatosis with erythematous-squamous plaques.
Acne: Inflammatory damage to the pilosebaceous follicle.
Impetigo: Contagious superficial skin infection.
Erysipelas: Acute dermal skin infection, often well limited.
Dermatophytia: Superficial mycosis due to dermatophytes.
Candidiasis: Candida mucocutaneous infection as principle.
Ringworm: Dermatophytia of the scalp or hair.
Scabies: Contagious cutaneous ectoparasitosis responsible for pruritus.
Pediculosis: Lice infestation depending on location.
IST: Sexually transmitted infection, approached in a medical and preventive context.
Syphilis: Bacterial STIs with possible mucocutaneous and systemic expressions.
Cutaneous leishmaniasis: Cutaneous parasitic infection linked to the epidemiological context.
Cutaneous tuberculosis: Skin damage linked to tuberculosis, often chronic.
Urticaria: Dermatosis with fleeting and migratory itchy lesions.
Angioedema: Deep edema which may become urgent depending on location.
Pemphigus: Autoimmune bullous dermatosis with possible mucosal damage.
Bullous pemphigoid: Autoimmune bullous dermatosis common in the elderly.
Basal cell carcinoma: Frequent skin tumor with especially local aggressiveness.
Squamous cell carcinoma: Skin tumor which may have a risk of extension depending on its form.
Melanoma: Malignant melanocytic tumor whose early diagnosis is crucial.
Venous ulcer: Leg ulcer linked to venous insufficiency.
Arterial ulcer: Ulcer linked to insufficient arterial supply.
Alopecia: Diffuse or localized reduction or loss of hair.
Dyschromia: Skin color abnormality, hypo- or hyperpigmented.
Occupational dermatosis: Dermatosis favored or caused by professional activity.
Dermocorticoid: Local corticosteroid used in certain inflammatory dermatoses according to indication.

Single source for structuring the module: https://univ.ency-education.com/6an_lessons-dermato.html. This sheet is an educational review summary and does not replace the advice of a teacher or a medical team.