Patch Testing in 1,267 Portuguese Patients With Chronic Hand Eczema

November 11, 2026

Doctor’s Notes · Life in Motion · Evidence Review

Editorial disclosure: The featured image is an AI-created illustration of a fictional work or daily-life scene. It is not a patient, diagnosis, before-and-after image or Dr. Arsy #003 treatment result.

Reader question: How often was sensitization clinically relevant in Portuguese chronic hand eczema?

Study snapshot

Study element	Reported detail
Population	1,267 chronic-hand-eczema patients evaluated across Portuguese dermatology departments between 2021 and 2023.
Design	Multicenter retrospective observational study of patch-test results.
Comparator	Atopic versus non-atopic groups and occupational versus non-occupational groups.
Timepoint	2021-2023.
Key result	Fifty-seven percent had at least one positive patch-test reaction and 41% of positive reactions were considered currently relevant. Metals, preservatives, fragrances, rubber constituents and 2-hydroxyethyl methacrylate were prominent; occupational cases had higher relevance for metals and benzisothiazolinone.
Funding/conflict context	Funding and conflicts are not stated in the indexed abstract. #003 was not studied.

What was actually measured?

Fifty-seven percent had at least one positive patch-test reaction and 41% of positive reactions were considered currently relevant. Metals, preservatives, fragrances, rubber constituents and 2-hydroxyethyl methacrylate were prominent; occupational cases had higher relevance for metals and benzisothiazolinone.

A positive patch test demonstrates sensitization, while current relevance additionally requires compatible exposure and clinical timing. The 41% figure applies to positive reactions, not automatically to all patients.

The denominator defines the scope. A patch-test clinic, selected case series, compensation registry, online questionnaire, workplace cohort and general-population survey answer different questions. A percentage from one cannot be silently transferred to the others.

What the result does not prove

Retrospective records, referred patients, center-to-center practice variation and clinician relevance judgments limit population inference.

Association, timing and biological plausibility can strengthen an occupational interpretation, but observational evidence cannot automatically establish individual causation. Referral patterns, reporting practices, task mix, protective equipment, nonwork exposures and access to care may all change an estimate.

A PubMed record is a bibliographic source. PubMed indexing is not NIH endorsement of the authors' conclusions, this interpretation or any product.

Exposure detail matters more than the job label

Workers with the same title can handle different materials for different durations. Useful documentation identifies the exact product or process, the route of contact, glove or PPE material, wetness, friction, heat, dust, splash potential, frequency and how symptoms change away from the task.

A symptom survey can identify a pattern, a clinical examination can refine the differential diagnosis, and patch testing can identify delayed sensitization. None of those steps alone proves that a workplace material caused an individual condition. Clinical relevance still requires a credible exposure and time course.

Questions worth recording

Which task, product, glove, tool, metal, resin, cleanser, food, plant, dust or surface came before symptoms?
Where did the change begin, and did it improve on days away or after a process or PPE change?
How often were hands wet, washed, disinfected, occluded, rubbed, heated or exposed to cold?
Were labels, ingredient information and safety-data sheets reviewed with occupational health?
Did the problem affect dexterity, sleep, pace, attendance, work quality or safety?

Prevention comes before cosmetic care

Substitution, closed systems, local exhaust, splash control, safer cleaning methods, training and correctly selected protective equipment address exposure at its source. Gloves are not automatically protective: material, fit, breakthrough time, sweating, reuse and rubber accelerators all matter.

Do not deliberately place workplace products on skin to test a theory. Persistent, recurrent or spreading symptoms, drainage, fever, breathing symptoms, severe pain, rapidly worsening redness or major loss of function warrant professional evaluation.

Primary research and guidance

Where Dr. Arsy #003 fits

Dr. Arsy #003 is a cosmetic moisturizer for hydration, moisture-barrier support and dry-skin comfort. This study did not test #003. Its findings do not show that #003 treats, cures or prevents eczema, relieves pain or itch, neutralizes workplace chemicals, is appropriate for every person, or provides pediatric or 24-hour efficacy.

Continue the evidence series

Evidence note: This educational article separates reported findings from interpretation. It is not a diagnosis, treatment recommendation or workplace-safety determination.

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