Étude prospective multicentrique 1991-2001 de la batterie standard des photopatch-tests de la Société Française de Photodermatologie

Contribution of phototesting in the diagnosis of photodermatoses: Retrospective study of 100 cases

BACKGROUND

Photodermatoses are sun-related inflammatory skin diseases. They usually require phototesting in diagnosis. However, fewer and fewer medical centers in France are equipped with photobiological equipment.

OBJECTIVES

The main purpose was to evaluate the relevance of phototesting in photodermatosis diagnosis. The second goal was to study the proportions of the different kinds of photodermatosis found in this particular study.

METHODS

This study was descriptive, retrospective, and mono-centric. It was based on 100 consecutive patients, who have been phototested in a French University Hospital from 2014 to 2018. Phototesting included determination of the minimal erythematous dose (MED), UVA and UVB phototests, and photopatch testing.

RESULTS

The use of phototesting led to 60% of photodermatosis diagnosis and formally eliminated the latter in 13% of the cases. The diagnosis remained undetermined in 27% of the cases. Nineteen cases of polymorphous light eruption (PLE), 14 cases of photocontact dermatitis (PCD), 10 cases of solar urticaria, 8 cases of photo-aggravated atopic eczema, 5 cases of chronic actinic dermatitis, and 2 cases of systemic photosensitization were diagnosed. The allergens involved in PCD were topical non-steroidal anti-inflammatory drug (NSAID) in 9 cases, sunscreens in 3 cases, and fragrance in 2 cases. The average amount of time between the first symptoms and actual phototesting was about 7,5 years.

CONCLUSION

This study confirms phototesting is truly useful. PLE was the most common form of photodermatosis, followed by PCD and solar urticaria. As photodermatosis could imply severe diseases sometimes requiring hospitalization, it is critical to maintain this expertise.

Contact Dermatitis: Classifications and Management

Contact dermatitis (CD) is a common inflammatory skin disease caused by exposure to contact allergens and irritants. It is also the most common reason of occupational dermatitis and contributes greatly to hand dermatitis and facial dermatitis. Besides the two major forms of contact dermatitis: allergic contact dermatitis and irritant contact dermatitis, other subtypes of CD have been recognized including immediate skin reactions, photoinduced contact dermatitis, systemic contact dermatitis, and non-eczematous contact dermatitis. CD is a great imitator which can mimic many kinds of skin diseases, such as atopic dermatitis, lichen planus, and angioedema. For the diagnosis of CD, a complete medical history, including occupational history, is very important. It can give a clue of CD and provide a list of suspected substances. Besides the well-known diagnostic test, patch testing, there are many other diagnostic tests can be used to help diagnosis of CD and identify the causative allergens, including photopatch test, skin tests for detecting of immediate contact reactions, serum allergen-specific IgE test, and qualitative and quantitative testing of allergen in the suspected materials patients exposed to and challenge test. Before the treatment, the suspected irritants or allergens should be avoided completely. This includes both the removal of the patient from the environment that contains those substances and the promotion of the metabolism and expulsion of the allergens that have been absorbed by the body. In addition, it is also important to restore the skin barrier and reduce skin inflammation through multiple treatments, such as emollients, topical corticosteroids, and antihistamines, as well as systemic corticosteroids and immunosuppressants. Early and appropriate treatments are important to prevent further deterioration and persistence of the skin condition.

Photopatch Testing in New Zealand: A 12-Year Retrospective Review

BACKGROUND

Little is known about the common photoallergens in New Zealand, where ultraviolet exposure is particularly high. Availability of photopatch testing is limited because of it being performed in very few tertiary referral and contact dermatitis clinics.

OBJECTIVE

To review the photopatch testing experience in New Zealand.

METHOD

A retrospective review of all patients who underwent photopatch testing at a tertiary referral center in Auckland from 2008 to 2019 was performed.

RESULTS

Seventy patients had photopatch testing over the 12-year period. Of the 58 patients tested using the photoallergen series, 6 (10%) patients had a positive photopatch test reaction, of which 4 were to promethazine and 2 were to benzophenone-3. The most common postpatch diagnosis was endogenous dermatitis (54%), followed by allergic contact dermatitis (21%), photoallergic contact dermatitis (9%), and chronic actinic dermatitis (4%).

CONCLUSIONS

Both patch and photopatch testing are important investigations in patients with suspected photoallergic contact dermatitis. Promethazine and benzophenone-3 were the most frequent and only photoallergens in our population. Promethazine sensitization was via oral exposure, supporting a mechanism of systematized photoallergy to promethazine.

Safety profile of topical diclofenac: a meta-analysis of blinded, randomized, controlled trials in musculoskeletal conditions

BACKGROUND

Topical non-steroidal anti-inflammatory drugs (NSAIDs) are clinically proven for the management of musculoskeletal conditions. It is important that prescribers and patients are aware of the safety profile of topical NSAIDs.

OBJECTIVES

To evaluate the risk of adverse events (AEs) associated with topical diclofenac for the treatment of acute and chronic musculoskeletal conditions.

DESIGN

Systematic review and meta-analysis of blinded, randomized, placebo-, vehicle- or active-controlled trials.

RESULTS

The risk of any type of AE experienced with topical diclofenac was slightly higher compared with placebo/vehicle (RR 1.11), but was more than 50% lower than the risk observed with active topical comparators (RR 0.53). Absolute risk values indicated differences in the risk of AEs depending on the diclofenac formulation used; in particular, lower rates of local skin reactions were observed with diclofenac patches (e.g. 2.5% in placebo/vehicle-controlled studies) and gels (4.2%) compared with diclofenac solutions containing dimethylsulfoxide (34.2%). Dry skin/crusting and rash were the most common local skin reactions reported (9.0% and 3.0% of patients, respectively, in placebo/vehicle-controlled studies), which were usually mild-to-moderate and self-resolving. The discontinuation rate due to local skin reactions with topical diclofenac (1.9%) was low and comparable with non-active comparators (0.7%), and the tolerability of topical diclofenac treatment was rated as 'good' to 'excellent' by >90% physicians and patients.

CONCLUSIONS

Topical diclofenac appears to be generally well tolerated for cutaneous use in acute and chronic musculoskeletal conditions.

A 20-year analysis of previous and emerging allergens that elicit photoallergic contact dermatitis

BACKGROUND

Retrospective chart reviews are periodically needed to update allergen series to detect changes in photoallergic contact dermatitis (PACD) over time.

OBJECTIVE

We sought to evaluate photopatch test results during a 13-year period and extend the observations to 20 years.

METHODS

A retrospective chart review was conducted in patients who were photopatch tested.

RESULTS

In all, 76 patients were evaluated. A total of 69 positive photopatch and 45 positive patch test reactions were detected in 30 and 23 patients, respectively. The frequencies of the positive photopatch test reactions were sunscreens 23.2%, antimicrobial agents 23.2%, medications 20.3%, fragrances 13%, plants and plant derivatives 11.6%, and pesticides 8.7%. Of the positive photopatch reactions to antimicrobial agents, 60% were caused by Fentichlor.

LIMITATIONS

This study was a retrospective chart analysis, and the number of patients was small.

CONCLUSIONS

Sunscreens and antimicrobial agents were the most frequent allergens eliciting PACD, and there was a decrease in PACD caused by fragrances. The number of reactions to medications increased. This study also demonstrated that pesticides can be a cause of PACD. The detection of reactions to Fentichlor was unexpected and, although they have been attributed in some studies to cross-reactions to sulfanilamides and bithionol, such a robust association was not observed in this study. This study extends our experience of the changes in the allergens that elicit PACD to 20 years.

[Photopatch testing]

This article reminds a review of photopatch tests with detailed analysis of: (1) materials used for double patch tests, and where possible, triple copies, one of which is protected from light while the other is exposed to UVA (5mJ/cm2) and the other exposed to UVB or a total spectrum of 0.75 DEM (minimum erythematous dose), with at least two readings; (2) interpretation of results to distinguish between contact allergy, contact photoallergy and/or phototoxicity; (3) materials used for UV exposure; (4) the list of (photo)allergens used in a standard series and/or a series specifically suited to the patient as well as suppliers of such series; (5) finally, the circumstances prompting photodermatological exploration.

Topical diclofenac and its role in pain and inflammation: an evidence-based review

OBJECTIVE

Topical diclofenac is widely used in the treatment of pain and inflammation. This comprehensive review assesses the safety and efficacy of topical diclofenac in a range of painful and inflammatory disorders.

METHODS

Double-blind, randomized, placebo- or active-controlled trials (RCT) evaluating topical diclofenac in soft-tissue injuries, soft-tissue rheumatic disorders and osteoarthritis were identified through detailed literature searches. In addition, non-RCT evidence from publications evaluating the pharmacologic characteristics of topical diclofenac were also included in this review to obtain a more complete picture of the drug's profile, its efficacy and safety.

RESULTS

Studies demonstrate that the drug preferentially distributes to the target tissues in sufficient concentrations to produce a therapeutic effect. A total of 19 double-blind RCTs in more than 3000 patients, supported by single-blind or open trials, consistently show that topical diclofenac significantly reduces pain and inflammation in acute and chronic conditions compared with placebo and is comparable to other topical non-steroidal anti-inflammatory drugs (NSAIDs) and some oral NSAIDs (diclofenac, ibuprofen, naproxen). Improvements have also been observed in patients' functional capacity and mobility. Topical diclofenac is well tolerated, resulting mostly in mild, easily resolved local skin irritation, and is associated with fewer side-effects than other topical NSAIDs and a lower rate of gastrointestinal complications than oral NSAIDs (diclofenac, ibuprofen, naproxen).

CONCLUSION

This evidence-based review shows topical diclofenac to be an effective and well tolerated treatment in painful and inflammatory conditions, at least in the short-term. However, only published RCT studies have been included in this analysis, which may exclude some interesting data from non-RCT studies. Future trials of topical diclofenac need to be of longer duration, be better reported and consider a broader spectrum of acute and chronic pain indications.