vitiligo
Enable an agent to recognise a recorded case of vitiligo, represent its extent and activity, and support decisions about assessment, management and follow-up without substituting for clinical diagnosis.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to recognise a recorded case of vitiligo, represent its extent and activity, and support decisions about assessment, management and follow-up without substituting for clinical diagnosis.
Vitiligo is an acquired, usually chronic disorder in which loss of functional melanocytes produces well-demarcated depigmented patches of skin, sometimes involving hair and mucosal surfaces, with autoimmunity central to the common nonsegmental form.
It can be Organise diagnostic evidence and flag unresolved alternative explanations for clinical review.; Compare dated lesion maps, photographs and compatible extent scores.; Distinguish disease spread, repigmentation and relapse at individual sites.; Record patient priorities and prepare a clinician-facing discussion of management options.; Track interventions, tolerability and outcomes against stated goals.; Identify missing assessment information and support referral for clinical or psychosocial needs..
Distinguishing features
Acquired areas of depigmentation support vitiligo more directly than congenital or lifelong generalised pigment reduction; onset history and examination must establish the distinction.
Depigmented patches without a primary scaly eruption favour vitiligo over some superficial fungal or inflammatory causes, but appearance alone does not settle the diagnosis.
Wood's lamp findings can help establish the boundaries and degree of depigmentation; record the examination result without treating it as an independently definitive test.
A preceding inflammatory eruption, chemical exposure or injury requires evaluation of alternative explanations; trauma-associated onset alone does not distinguish vitiligo.
Segmental and nonsegmental distribution patterns help classify vitiligo after diagnostic assessment; white hair within a patch is relevant supporting evidence rather than a mandatory feature.
Scope
+ Evidence supporting vitiligo and uncertainty about alternative causes of pigment loss
+ Clinical subtype, anatomical distribution and involvement of hair or mucosal sites
+ Depigmentation extent, disease activity and change over time
+ Functional, psychosocial and patient-reported impact
+ Management goals, intervention history and observed outcomes
- Other causes of hypopigmentation or depigmentation as independently modelled conditions
- Associated autoimmune diseases and their complete diagnostic or treatment pathways
- Drug composition, manufacturing and regulatory approval records
- Phototherapy device engineering and maintenance
- General skin anatomy, melanocyte biology and pigmentation genetics beyond their relevance to vitiligo
Characteristics
- Diagnostic status
- suspected | clinician-diagnosed | uncertain | revised, with assessor and date Separates an observed pigment change from an established clinical interpretation.
- Clinical subtype
- segmental | nonsegmental | mixed | unclassified, with classification reference Distribution and course influence assessment and management expectations.
- Affected sites
- anatomical sites, laterality and symmetry; hair and mucosal involvement recorded separately Total area alone cannot express distribution, visibility or site-specific response.
- Depigmentation extent
- percentage of body surface area or named instrument score, with method, region and date Allows change to be assessed without conflating incompatible scoring methods.
- Disease activity
- active | stable over a stated interval | uncertain, with supporting observations New or enlarging lesions must be distinguished from longstanding residual depigmentation.
- Hair depigmentation
- present | absent | not assessed, by affected site Records involvement that skin-area measurements may omit.
- Patient-reported burden
- named instrument and score or patient-described impact, with date Visible extent is not a reliable substitute for distress or interference with daily life.
- Management goal
- limit progression | repigmentation | maintain response | camouflage | psychosocial support | observation; multiple values allowed Makes success depend on the person's priorities rather than pigment change alone.
- Associated condition assessment
- links to separately recorded conditions or assessments, with suspected versus confirmed status Preserves relevant clinical context without implying that an association establishes another diagnosis.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.vitiligo
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 19 findings · 29 questions.
Diagnostic identity Establish what supports calling the observed pigment loss vitiligo.
Pigment loss has multiple causes, and a registry label must not turn diagnostic uncertainty into certainty.
Depigmentation evidence
Record the observed phenotype and how it was examined.
Observed pigment loss
Separate patient-reported colour change, clinical examination and supplementary examination results.
- What evidence establishes depigmentation rather than partial hypopigmentation, and at which sites? definition
- Who assessed the patches, when, and with what examination methods, including any Wood's lamp assessment? provenance
Diagnostic boundaries
Preserve alternatives and the reasoning used to distinguish them.
Alternative causes
Consider onset, preceding inflammation, surface changes and exposures without treating any single feature as decisive.
- Which alternative explanations, such as post-inflammatory pigment loss, superficial fungal disease or chemical leukoderma, remain plausible? boundary
- What unresolved observation requires clinical reassessment before the record can be treated as established vitiligo? action
Distribution and extent Represent the pattern and amount of depigmentation across skin, hair and relevant mucosal sites.
Vitiligo cannot be adequately characterised by a single affected-area value.
Clinical pattern
Connect subtype assignment to actual anatomical observations.
Subtype and site map
Record distribution, laterality, symmetry and the basis for segmental, nonsegmental, mixed or unclassified status.
- Which distribution findings support the assigned subtype, and which classification was used? definition
- Which skin regions, hair-bearing areas or mucosal sites are involved, and which were not assessed? measurement
Extent assessment
Make area estimates and scoring instruments interpretable and comparable.
Regional depigmentation
Retain regional extent and degree of pigment loss alongside any overall score.
- What extent was recorded using body surface area estimation, VASI or another named method, and what regions does that value cover? measurement
- Were the same method, anatomical coverage and assessment conditions used for the comparison measurement? provenance
Activity and course Distinguish ongoing pigment loss from stable lesions, repigmentation and recurrence.
A static lesion map does not show whether vitiligo is spreading or whether improvement is durable.
Progression and stability
Anchor activity assessments to explicit observations and time windows.
Activity evidence
Record new lesions, enlargement and other clinician-assessed activity evidence without assuming that absent documentation means stability.
- Have new patches or enlargement of existing patches occurred, at which sites and over what interval? measurement
- What evidence and observation period support a statement that the disease, or an individual patch, is stable? provenance
Repigmentation and recurrence
Track recovery of pigment and subsequent loss at the same sites.
Site-level trajectory
Distinguish repigmentation from photographic variation, changing surrounding skin colour and spread elsewhere.
- Which sites show repigmentation, persistent depigmentation or renewed pigment loss relative to dated baseline observations? measurement
- Could lighting, tanning, camouflage or image-processing differences explain part of the apparent change? boundary
Personal impact and context Capture the person's experience and clinically relevant context beyond lesion extent.
Vitiligo burden depends on visibility, social experience and individual priorities as well as physical findings.
Lived impact
Record distress, participation and preferences in the person's own terms.
Burden and priorities
Keep patient-reported impact separate from clinician-rated extent.
- How do pigment changes affect daily activities, relationships, self-image or experiences of stigma? measurement
- Which affected sites or concerns matter most to the person, and what support do they want? action
Associated health context
Link relevant histories and assessments without embedding separate disease models.
Contextual assessment
Preserve symptoms, personal or family history and clinician decisions relevant to associated conditions.
- What personal history, family history or symptoms were documented as relevant to assessment for associated autoimmune conditions? provenance
- Which associated conditions are confirmed, which are only suspected, and what assessment has a clinician indicated? boundary
Management and response Connect chosen care to goals, suitability, treatment exposure and observed outcomes.
Limiting spread, restoring pigment and reducing personal burden are distinct goals with different measures of success.
Care selection
Document shared decisions and the clinical context supporting them.
Goals and suitability
Record the rationale for observation, topical treatment, phototherapy, procedural approaches, camouflage or support without prescribing from the model alone.
- Is the agreed goal to limit spread, repigment particular sites, maintain improvement, reduce burden or observe the course? action
- How did subtype, activity, affected sites, age, prior response and patient preferences inform the clinician's proposed approach? provenance
Response and review
Interpret outcomes against actual intervention exposure and follow-up duration.
Benefit, tolerability and durability
Record regional response, adverse effects, practical burden and persistence of benefit while preserving uncertainty about causation.
- What intervention exposure and follow-up interval preceded the observed changes in activity, pigmentation and patient-reported impact? measurement
- What benefit, adverse effects, burden or recurrence prompted a clinician-supervised decision to continue, modify or stop the approach? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- This describes the dermatological condition; the supplied domain code alone does not establish a narrower sense.
- Listed varieties mix major classifications with distribution patterns; they are not mutually exclusive, and focal or mucosal disease may require follow-up for classification.
- This is recall rather than source-verified research; verify guideline currency and exact scoring conventions before operational use.
- Which of these check these first hold for the sense of vitiligo this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Nonsegmental vitiligo, including generalized and acrofacial patterns
- Segmental vitiligo
- Mixed vitiligo, combining segmental and nonsegmental disease
- Universal vitiligo, involving nearly all skin
- Focal vitiligo, whose classification may depend on subsequent evolution
- Mucosal vitiligo
- Which of these kinds and varieties hold for the sense of vitiligo this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- ICD-10 - L80 - World Health Organization classification code for vitiligo.
- Which of these identifiers and schemes hold for the sense of vitiligo this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- British Association of Dermatologists guidelines for the management of people with vitiligo, 2021.
- Which of these standards and regulation hold for the sense of vitiligo this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Clinical diagnosis and classification of acquired depigmentation.
- Assessment of disease activity and extent to guide treatment and follow-up.
- Evaluation of repigmentation and disease stabilization in clinical trials.
- Assessment of psychosocial burden and associated autoimmune disease when clinically indicated.
- Which of these real-world use hold for the sense of vitiligo this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Depigmented body surface area - Possible range 0-100; extent varies substantially between patients. - %
- Vitiligo Area Scoring Index (VASI) - Theoretical total-body range 0-100, combining affected area with degree of depigmentation. - score
- Vitiligo Disease Activity score (VIDA) - -1 to +4, reflecting reported stability or recency of disease activity. - ordinal score
- Which of these typical measurements hold for the sense of vitiligo this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Depigmented skin is more susceptible to sunburn.
- Visible changes can cause stigma, psychological distress and impaired quality of life.
- Disease progression and relapse after repigmentation can occur; individual course is difficult to predict.
- Skin injury can trigger new lesions through the Koebner phenomenon.
- Association with autoimmune thyroid disease and some other autoimmune conditions can be clinically relevant.
- Which of these failure modes and hazards hold for the sense of vitiligo this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Reported prevalence varies across populations and study methods; estimates are not directly interchangeable.
- Social consequences vary with cultural attitudes and the visual contrast between affected and surrounding skin.
- Access to specialist assessment, phototherapy and medicines varies by health system.
- Which of these regional variation hold for the sense of vitiligo this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Albinism - Albinism comprises inherited disorders of melanin production, generally evident early in life; vitiligo is acquired and involves loss of functional melanocytes.
- Post-inflammatory hypopigmentation - Pigment reduction follows preceding inflammation or injury and is often incomplete; vitiligo typically produces depigmented patches without that preceding inflammatory process.
- Pityriasis versicolor - This superficial Malassezia-associated condition commonly produces finely scaling patches and can be supported by fungal microscopy; vitiligo patches ordinarily lack scale.
- Chemical leukoderma - Exposure history and lesion distribution implicate melanocyte-damaging chemicals, although clinical and biological overlap with vitiligo can make separation difficult.
- Nevus depigmentosus - Typically appears at birth or early childhood and remains relatively stable in distribution, whereas vitiligo is acquired and may spread.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of vitiligo this model covers, and on what evidence? provenance
What the second pass must settle
- Which clinical classification should anchor the model, particularly for mixed, focal and isolated mucosal presentations?
- Which operational definitions and observation periods should represent stability for routine monitoring versus consideration of procedural treatment?
- Which extent and patient-reported instruments are sufficiently validated across ages, skin tones and care settings, and when are their results comparable?
- How should the model represent the boundary between chemical-associated depigmentation and vitiligo when clinical interpretations differ?
- Which current, jurisdiction-specific guidance should govern associated-condition assessment and treatment suitability, and how should changes to that guidance be versioned?