A Randomised Assessor Blinded Comparison of Low Irradiance and Conventional Irradiance Photodynamic Therapy for Superficial Basal Cell Carcinoma and Bowen's Disease

The inconvenience and pain of hospital-based photodynamic therapy (PDT) is sometimes limiting.¹ We developed very low irradiance LEDs for ambulatory PDT. Preliminary studies showed this to be convenient and relatively painless.^1-4 Here we evaluate the Ambulight® device (Ambicare Health Ltd) in a randomised controlled assessor-blinded study comparing low irradiance ambulatory PDT (APDT) with conventional PDT (CPDT) for superficial basal cell carcinoma (SBCC) and Bowen's disease (BD) (lesions ≤2cm).

Photodiagnostic services in the UK and Republic of Ireland: a British Photodermatology Group Workshop Report

BACKGROUND

Photodiagnostic investigations are essential for the accurate diagnosis of abnormal cutaneous photosensitivity and provide important information for the management of patients with photodermatoses (cutaneous photosensitivity disorders). Although photodiagnosis has been undertaken since the early 1970s, specialist services in the United Kingdom (UK) and Republic of Ireland are limited and there is no formal guidance on diagnostic approach. Indeed, there is a limited literature in this area of methodology and diagnostic practice.

OBJECTIVES

The primary objective was to undertake a British Photodermatology Group Workshop to review the role and activities of specialist centres in the UK and Republic of Ireland in order to ascertain whether there were consensus practices. Secondary objectives were to identify key priorities for service, training and research.

METHODS

An initial detailed survey review of current activities was undertaken prior to the Workshop and data from this survey were used to inform discussion at the Workshop, which was attended by key photodermatology experts from the UK and Republic of Ireland.

RESULTS/CONCLUSIONS

We have undertaken a detailed review of current Photodiagnostic Services in the UK and Republic of Ireland and report on our findings from the 12 centres and we have identified key areas of consensus practice. This is an important step in the process of standardising and optimising procedures and protocols and defining minimum clinical standards for photodiagnostic investigations, which are of such diagnostic importance in Dermatology.

A review of photodiagnostic investigations over 26 years: experience of the National Scottish Photobiology Service (1989-2015)

Background The Scottish Photobiology Service is the national referral pathway for patients with cutaneous photosensitivity diseases in Scotland. We reviewed the pattern of diagnosis of photosensitivity diseases and investigations performed between 1989 and 2015. Methods and Results Data were collected from the Photodiagnostic Database, annual reports and paper records. The total number of patients assessed each year was stable over the period studied (median 242 [range 231-266]), with most being new patients (median 69 [range 62-73]%). Monochromator phototesting was the most utilised investigation, although the use of provocation testing and photopatch testing has increased. The most common diagnosis was polymorphic light eruption, and there was a trend to increasing diagnosis of photoaggravated atopic eczema. Conclusions The pattern of diagnosis of photosensitivity diseases remains fairly stable in Scotland and we wish to emphasise the importance of this Scottish specialist service for patients with photosensitivity diseases and referrers.

The widespread use of topical antimicrobials enriches for resistance in Staphylococcus aureus isolated from patients with atopic dermatitis

BACKGROUND

Carriage rates of Staphylococcus aureus on affected skin in atopic dermatitis (AD) are approximately 70%. Increasing disease severity during flares and overall disease severity correlate with increased burden of S. aureus. Treatment in AD therefore often targets S. aureus with topical and systemic antimicrobials.

OBJECTIVES

To determine whether antimicrobial sensitivities and genetic determinants of resistance differed in S. aureus isolates from the skin of children with AD and healthy child nasal carriers.

METHODS

In this case-control study, we compared S. aureus isolates from children with AD (n = 50) attending a hospital dermatology department against nasal carriage isolates from children without skin disease (n = 49) attending a hospital emergency department for noninfective conditions. Using whole genome sequencing we generated a phylogenetic framework for the isolates based on variation in the core genome, then compared antimicrobial resistance phenotypes and genotypes between disease groups.

RESULTS

Staphylococcus aureus from cases and controls had on average similar numbers of phenotypic resistances per isolate. Case isolates differed in their resistance patterns, with fusidic acid resistance (Fus^R ) being significantly more frequent in AD (P = 0·009). The genetic basis of Fus^R also differentiated the populations, with chromosomal mutations in fusA predominating in AD (P = 0·049). Analysis revealed that Fus^R evolved multiple times and via multiple mechanism in the population. Carriage of plasmid-derived qac genes, which have been associated with reduced susceptibility to antiseptics, was eight times more frequent in AD (P = 0·016).

CONCLUSIONS

The results suggest that strong selective pressure drives the emergence and maintenance of specific resistances in AD.

Lack of phototoxicity potential with delafloxacin in healthy male and female subjects: comparison to lomefloxacin

AIMS

Delafloxacin is a fluoroquinolone antibiotic recently approved by the FDA for treatment of acute bacterial skin and skin structure infections (ABSSSI). Delafloxacin was assessed for phototoxicity potential compared with a known phototoxic fluoroquinolone.

METHODS

A Phase 1, investigator-blind, placebo/active-controlled, randomized, parallel-group study was conducted in 52 healthy male and female volunteers who received 200 or 400 mg of oral delafloxacin, 400 mg oral lomefloxacin or placebo once daily for 6 days. This study evaluated the photosensitizing potential and possible wavelength dependency of delafloxacin by comparing the response of the skin to ultraviolet A (UVA), ultraviolet B (UVB) and visible radiation prior to and during administration of delafloxacin, lomefloxacin as a positive control, or placebo. Adverse events were monitored throughout the study.

RESULTS

Forty-seven subjects completed six days of dosing, and no evidence of phototoxicity was seen with delafloxacin. Delafloxacin at 200 and 400 mg day-1 and placebo did not demonstrate differences in percent change from baseline in minimal erythema dose at all tested wavelengths (295-430 nm) by monochromator and solar simulator. Lomefloxacin, the positive control, had statistically significant differences (p < 0.05) at UVA wavelengths of 335 and 365 ± 30 nm 24 hours after radiation exposure (maximum response). The phototoxic index results were significantly higher for lomefloxacin at 335 nm and 365 nm compared to placebo and delafloxacin.

CONCLUSIONS

200 and 400 mg of delafloxacin administered for 6 days were well tolerated in healthy adult volunteers. Delafloxacin and placebo failed to demonstrate a phototoxic effect but lomefloxacin, the positive control, demonstrated moderate phototoxicity.

Six years' experience of grenz ray therapy for the treatment of inflammatory skin conditions

BACKGROUND

In 2008, Ninewells Hospital became the first centre in the UK to offer grenz rays as a treatment for inflammatory dermatoses. Since then, 122 courses have been administered for the following conditions; scalp psoriasis (n = 36), nail dystrophies (n = 27), hyperkeratotic eczema/psoriasis (n = 22), palmoplantar pustulosis (n = 9), perianal pruritus (n = 9), warts (n = 4) and other conditions (n = 15).

AIM

To review all patients who received grenz rays in order to determine which conditions have been treated successfully and to estimate remission times.

METHOD

Patient notes were reviewed, and follow-up was supplemented by subsequent dermatology clinic letters and telephone consultation.

RESULTS

For scalp psoriasis, clearance was achieved with 13 courses, marked improvement with 19, minimal improvement in 3 and no change with 1. Treatment of palmoplantar psoriasis/hyperkeratotic eczema showed clearance with 7 courses, marked improvement with 9, minimal change with 2 and no change with 4. Of the courses for nail dystrophies (mainly psoriasis), clearance occurred with 1, marked improvement with 7, minimal change with 8 and no change with 11. In addition to immediate outcomes, the remission times were also evaluated. For scalp psoriasis, only 8 of the initial 32 patients still had clearance or marked improvement at the most recent follow-up. For nail dystrophy, 3 of 8 patients remained in remission, while for hyperkeratotic eczema/psoriasis, 7 of the initial 16 patients who had clearance or marked improvement had sustained this improvement, and only 1 patient with palmoplantar pustulosis still had clearance at the most recent follow-up.

CONCLUSIONS

Grenz ray therapy is an effective treatment for some chronic inflammatory skin conditions that are resistant to routine therapies. The period of remission for scalp psoriasis was good for some patients but disappointingly short for others. Future studies involving different cumulative doses with subsets of different dose fractionations may help optimize treatment regimens.

Review of an established UK home phototherapy service 1998-2011: improving access to a cost-effective treatment for chronic skin disease

OBJECTIVES

To review the Tayside home phototherapy service, including numbers of patients treated, diagnoses and outcomes, side-effects and safety, cost-effectiveness and absolute costs. To consider why home or outpatient phototherapy is not available to all patients who might benefit and how this could be addressed.

STUDY DESIGN

Observational and cost analysis.

METHODS

Analysis of the Tayside home phototherapy database 1998 and 2011, home phototherapy patient questionnaires, outcome data, costs and a comparison with outpatient phototherapy. Review of literature and current national guidelines for phototherapy, traditional systemic and biologic therapies for psoriasis.

RESULTS

298 courses of home narrowband UVB (NB-UVB) phototherapy were undertaken by 212 patients between 1998 and 2011, five courses in 1998 increasing to 36 in 2011. The main diagnoses treated were psoriasis (72%), atopic dermatitis (8%), and desensitization of photodermatosis (7%). For psoriasis, 74.5% achieved clearance or minimal residual activity in a median of 30 exposures (range 10-60). The estimated costs to the hospital ranged from £229 to £314 per course (£307 to £422 per effective course for psoriasis), compared with £114 for out-patient therapy (£149 per effective course for psoriasis). The total cost to society (hospital and patient costs) is around £410 per course, compared to an estimated £550 for outpatient therapy for this group of patients. Treatment was well tolerated, erythema rates were similar to outpatient therapy, there were no complaints and the vast majority would choose home over outpatient phototherapy if required in the future.

CONCLUSIONS

Hospital supervised home phototherapy appears as safe and effective as outpatient therapy and provides equality of access for patients who cannot attend for outpatient therapy. These patients may otherwise be inadequately treated or given more costly and higher risk systemic therapies, particularly for psoriasis. Commissioners and clinicians involved in dermatology services should provide accessible phototherapy for all patients who might benefit, utilizing home phototherapy where outpatient access is not possible.

Delayed ultraviolet erythema not suppressed by oral prednisolone: a randomized crossover study

BACKGROUND

The anti-inflammatory potency of topical dermatological corticosteroids in suppressing ultraviolet (UV) erythema is routinely measured. No such model exists to assess the potency of systemically administered steroids.

OBJECTIVE

To determine whether or not suppression of delayed UV erythema by a systemic corticosteroid could provide a useful model for assessing the anti-inflammatory potency of systemic corticosteroids.

METHODS

We conducted a randomized, placebo-controlled, patient and assessor blinded, crossover study of oral prednisolone effects on the delayed UV-induced erythemal response in normal subjects. Six healthy volunteers were phototested with a xenon arc monochromator and then dosed with 30 mg of oral prednisolone or matching placebo daily for 4 days. Repeat phototesting was performed on the 4th day of dosing. The minimal erythema dose (MED) was assessed immediately after test UV doses were administered and 24 h later. After a 2-week washout period, the dosing and testing were repeated in a crossover fashion.

RESULTS

A suppression index (SI) [1/(baseline MED value divided by on prednisolone/placebo value)] allowed comparison of the degree of suppression on and off prednisolone. Oral prednisolone did not significantly suppress the threshold UV erythema response (MED). We may have missed small effects in this study and possibly a larger dose or a longer duration of corticosteroid would have had an effect. Possibly, assessment of corticosteroid potency in suppressing established UV erythema rather than on the development of threshold erythema would have yielded different results.

CONCLUSION

The threshold UV erythema suppression model assessed in this study could not distinguish between oral prednisolone and placebo. This UV-erythema suppression test system is not promising as a model to test the anti-inflammatory potency of systemic steroids.

Treatment options for non-melanoma skin cancer

Non melanoma skin cancers (basal cell carcinoma and squamous cell carcinoma) are becoming more common. There are many treatments including surgical modalities, use of electromagnetic radiations (as in photodynamic therapy), topical and intralesional chemotherapies and immunomodulating treatments. The choice as to how to treat a particular tumour depends not only on features of the tumour but characteristics of the patient and his or her preferences. There are up to date guidelines available that are useful when chosing treatments, but following these guidelines is not always appropriate to the individual. This is a personal review in which the author explains some of the reasons why he recommends one treatment over another in particular situations.

Reactivity to autologous serum skin test and relationship with complement levels in chronic idiopathic urticaria and angio-oedema

BACKGROUND

A role for complement in autoantibody-mediated histamine release in urticaria has been suggested but not proven in vivo. Aim. To study serum complement levels in patients with chronic idiopathic urticaria (CIU) and to determine whether there was a relationship with autologous serum skin test (ASST) reactivity.

METHODS

We recruited 35 patients with CIU. Complement (C3, C4) levels and ASST were measured in all patients; additional investigations were undertaken dependent on history and examination.

RESULTS

Complement concentrations were outside the population reference intervals in 19/35 patients, with low C3 noted in 3/35 and low C4 in 18/35. Of 12 patients with a positive ASST, 7 had low complement levels, and 12/23 with a negative ASST had low complement levels. Patients with a positive ASST had a median C3 of 1.24 g/L (range 0.35-1.51) compared with a median of 1.25 g/L in those with a negative ASST (P = 0.36), and a median C4 of 0.20 g/L (range 0.185-0.452) in those with a positive ASST compared with 0.18 g/L in those with a negative ASST (P = 0.88).

CONCLUSIONS

We conclude that both a reduction in C4 and positive ASST are common in CIU and although these immunological abnormalities often coexist, there is no clear relationship between them. Other components of the complement system may be worth exploring.

Does narrow-band ultraviolet B phototherapy work in atopic dermatitis through a local or a systemic effect?

The likely mechanisms of action of narrow-band ultraviolet B (NB-UVB) in atopic dermatitis are several. We attempted, in a 12 patient prospective intraindividually controlled study, to determine whether the effect of NB-UVB in atopic dermatitis is primarily through systemic or local effects. Change in observer-assessed severity of patches of dermatitis covered during each whole-body NB-UVB treatment was compared with change in uncovered neighbouring patches. We found great variation between patients in responses. Only in two (of 12) patients was there a large difference between directly exposed and covered patch dermatitis severity. We suspect that the balance of local and systemic effects important in determining response to NB-UVB in atopic dermatitis varies from patient to patient. This study did not conclusively answer our original question, but did show that in some patients localized effects of NB-UVB are important.

Regulation of cutaneous drug-metabolizing enzymes and cytoprotective gene expression by topical drugs in human skin in vivo

BACKGROUND

Individuality in the expression and regulation of hepatic drug-metabolizing enzymes (DMEs) and cytoprotective (CP) genes is an important determinant of treatment response. There is increasing evidence that many DMEs and CP genes are also expressed in human skin. Responses to topical drugs used to treat common skin diseases, such as psoriasis, are unpredictable and may potentially be rationalized, at least in part, by interindividual differences in cutaneous DME and CP gene expression.

OBJECTIVES

We investigated whether three topical drugs [coal tar, all-trans retinoic acid (atRA) and clobetasol 17-propionate] used in routine clinical practice modulated the expression of a variety of DME and CP genes [cytochrome P450s, glutathione S-transferases (GSTs) and drug transporters] in healthy human skin in vivo.

METHODS

Healthy adult volunteers (n = 30) were invited to participate in the study. Each subject was randomly allocated to receive two of the three study chemicals and one control site application. Crude coal tar (n = 13), atRA (n = 14) or clobetasol 17-propionate (n = 10) was applied under occlusion to photoprotected buttock skin for 96 h. A vehicle control (white soft paraffin) was also applied under the same conditions at an adjacent site in all subjects. Full-thickness punch biopsies (4-mm diameter) were then taken from treated and control sites. Total RNA was extracted and reverse transcribed into cDNA, which was used as a template in subsequent real-time polymerase chain reaction analysis, where fluorescent output was directly proportional to input cDNA concentration. Triplicate measurements of skin mRNA expression were made from each sample, and the arithmetic mean values taken. After logarithmic transformation, the paired t-test was used to compare values between treated and control skin.

RESULTS

Cytochrome P450s CYP1A1, CYP1A2, CYP1B1, CYP2C18, quinone reductase (NQO-1), GSTP1, gamma-glutamyl cysteine synthetase (gamma-GCS), glutathione peroxidase-1 (GPx-1), cyclooxygenase-2 (COX-2) and haem oxygenase-1 (HO-1) were induced by coal tar; CYP26, NADPH P450 reductase (CPR), GSTP1 and HO-1 by atRA; and CYP3A5 by clobetasol 17-propionate. In contrast, CYP1A1 and CYP1A2 expression was suppressed by atRA, and gamma-GCS and MRP1 by clobetasol 17-propionate. Marked interindividual variation in gene regulation by topical drugs was seen for the majority of genes examined.

CONCLUSIONS

These data demonstrate that topical drugs can modulate DME gene expression in human skin in vivo and indicate that variation in the expression and regulation of these genes may be a determinant of individuality in response to topical therapies for common skin diseases.

UVA1 phototherapy for treatment of necrobiosis lipoidica

The primary cause of collagen degeneration in necrobiosis lipoidica (NL) is proposed to be immunologically mediated vascular disease. Ultraviolet (UV)A1 has been used successfully to treat scleroderma in which both vascular damage and collagen dysregulation also occur. We treated six patients with NL [(five women; mean age of 32 years (range 22-70) and mean disease duration of 2.9 years (range 6 months to 5 years)] with a high-output ultraviolet (UV)A1 2-kW filtered metal halide source (Dr Hönle; Dermalight ultrA 1) having an emission spectrum of 340-440 nm. All patients had NL on the shins, which had been unresponsive to potent topical corticosteroid therapy (n = 6) and had responded minimally or not at all to TL-01 UVB (n = 2), topical psoralen plus UVA (PUVA) soaking (n = 2) or oral PUVA (n = 1) therapy. Patients received a variable number of total exposures (15-51), given 3-5 times weekly. NL resolved completely in one patient; this patient had minimal improvement after the first course of 16 exposures, but after a further 13 exposures, resolution occurred 6 months later. Two subjects obtained moderate improvement in their overall disease severity after 15 and 24 exposures, while two had only minimal improvement after 15 and 51 exposures. The remaining patient had no improvement after 16 treatments. Patients with the shortest disease duration had the greatest response. UVA1 therapy may be of benefit for the treatment of NL as an adjuvant therapy to topical corticosteroids or as a second-line alternative to other phototherapies, and may have a superior outcome in a proportion of patients.

UVA1 phototherapy for genital lichen sclerosus

BACKGROUND

Lichen sclerosus (LS) is characterized histologically by an inflammatory T-cell infiltrate, sclerosis and thickening of the dermis, and epidermal atrophy. Ultraviolet (UV) A1 therapy has been shown to be effective in the management of morphea and scleroderma, diseases that have some histological and clinical similarities with LS, and more recently in extragenital LS.

AIM

To determine the effectiveness of UVA1 therapy for genital LS.

METHODS

Seven women with severe genital LS uncontrolled by ultrapotent topical corticosteroids, with a median age of 62 years (range 48-78) and disease duration of 6-47 years, were treated with UVA1 therapy from a high output source. After completion of UVA1 therapy, a clinician and the patient graded the overall response of symptoms and physical signs.

RESULTS

Five patients improved with therapy. Three obtained moderate improvement in overall disease severity and two had minimal improvement. Of these five, one relapsed within 3 months and another after a year. Both had a further course of UVA1 therapy, resulting in minimal improvement in one and moderate improvement in the other. In the remaining three, disease severity had improved to a point where intermittent use of topical corticosteroids resulted in acceptable control.

DISCUSSION

UVA1 therapy may be of benefit in the management of vulval LS, a disease that is often poorly responsive to standard therapies. The therapy is well tolerated and could provide an acceptable therapeutic option for patients with severe disease.

Can St John's wort (hypericin) ingestion enhance the erythemal response during high-dose ultraviolet A1 therapy?

BACKGROUND

St John's wort (SJW) is widely used as a treatment for depression. A phototoxic reaction, due to its content of hypericin, can occur in animals and in cell culture, and has been reported in humans. Hypericin displays absorption within the ultraviolet (UV) A1 spectrum and there may therefore be a potential for phototoxicity if taken during high-dose UVA1 therapy.

OBJECTIVES

To assess the phototoxicity risk of SJW ingestion.

METHODS

Eleven adult volunteers of skin types I and II were exposed to a geometric dose series of UVA1 irradiation from a high-output source (Dermalight Ultra 1; Dr Hönle, Martinsreid, Germany; irradiance 70-77 mW cm(-2)) on the photoprotected lower back skin at eight 1.5-cm(2) test areas. Irradiation was carried out at baseline and after 10 days of SJW extract 1020 mg (equivalent to 3000 microg of hypericin) daily. Four, 8, 24 and 48 h after each exposure, the minimal erythema dose (MED) and the presence or absence of pigmentation were recorded visually and erythema was assessed objectively with an erythema meter.

RESULTS

The median MED and D(0.025), an objective measure of MED, were lower at all time-points after SJW ingestion. The visual erythemal peak (lowest median MED), which was seen at 8 h postirradiation, was lower after SJW (median 14 J cm(-2), range 10-56) than at baseline (median 20 J cm(-2), range 14-56) (P = 0.047). Similarly, the median D(0.025) at 8 h postirradiation was lower after SJW (median 22.0 J cm(-2), range 15.2-53.9) than at baseline (median 33.7 J cm(-2), range 22.9-136.0) (P = 0.014). The MED and D(0.025) were also significantly different at the 48-h and 4-h time-points, respectively. Significance was not reached at the 24-h time-point. Median intensity of postirradiation erythema increased at all time-points after ingestion of SJW. Despite these differences, the maximum slope of the dose-response curve was not increased after SJW ingestion.

CONCLUSIONS

These data suggest that SJW extract has the potential to lower the erythemal threshold to UVA1 irradiation in a significant proportion of individuals and highlight the importance of ascertaining a full drug history, including herbal remedies, before initiating UVA1 phototherapy.

The photocarcinogenic risk of narrowband UVB (TL-01) phototherapy: early follow-up data

BACKGROUND

Limited information is available on the carcinogenic risk associated with narrowband TL-01 UVB phototherapy in humans.

OBJECTIVES

To determine the skin cancer incidence in a population treated with TL-01 phototherapy.

PATIENTS AND METHODS

All TL-01-treated patients were identified from the departmental computerized database. Patients with malignant melanoma (MM), squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) were identified by record linkage with the Scottish Cancer Registry. The incidence of each was compared with the normal Scottish population matched for age and sex.

RESULTS

Data were obtained from 1908 patients. The median follow-up duration was 4 years (range 0.04-13). The median cumulative number of TL-01 treatments and dose were 23 (1-199) and 13 337 (30-284 415) mJ cm(-2), respectively. No increased incidence of SCC or MM was observed. Ten patients developed BCC compared with an expected 4.7 in the Scottish population [standardized rate ratio 213 (95% confidence interval 102-391); P < 0.05].

CONCLUSIONS

A small but significant increase of BCC was detected in the TL-01 group. This could be explained by a number of factors, including ascertainment bias. To determine the true carcinogenic risk of TL-01 phototherapy, longer follow-up is essential.

A randomized controlled comparison of the efficacy of Dead Sea salt balneophototherapy vs. narrowband ultraviolet B monotherapy for chronic plaque psoriasis

BACKGROUND

Dead Sea (DS) salt solution soaks are used in combination with narrowband ultraviolet B (NB-UVB) to treat psoriasis in many centres, particularly in continental Europe. No previously published controlled study has assessed DS salt + NB-UVB balneophototherapy.

OBJECTIVES

To compare DS salt balneophototherapy with NB-UVB monotherapy for chronic plaque psoriasis.

METHODS

Sixty patients with chronic plaque psoriasis participated in this paired, controlled study, with pretreatment DS salt soaks randomly allocated to each participant's right or left study limb. Psoriasis severity was assessed with a Scaling, Erythema and Induration score by a blinded observer. Assessments were weekly during the therapy course, and thereafter 8-weekly until relapse or for up to 1 year after clearance.

RESULTS

The mean area under the psoriasis severity-time curves during treatment was not detectably lower with DS salt balneophototherapy than with NB-UVB monotherapy (P = 0.099). The psoriasis severity score fell slightly more from beginning to end of courses with DS salt balneophototherapy than with NB-UVB monotherapy (P = 0.019). There was no detectable difference in times to relapse.

CONCLUSIONS

In this population the addition of pretreatment DS salt soaks to NB-UVB did not result in a clinically important improvement in clearance of psoriasis.

A pilot study of treatment of lentigo maligna with 5% imiquimod cream

BACKGROUND

Lentigo maligna (LM) is an in situ form of malignant melanoma, and surgical excision is often unsatisfactory. Imiquimod cream is an immune response modifier and induces a predominantly T-helper 1 type response.

OBJECTIVES

Assessment of histological and clinical response of surgically resectable LM after treatment with 5% imiquimod cream.

METHODS

Six patients with LM were treated with 5% imiquimod cream daily for 6 weeks. The whole site of the original lesion was then excised. Clinical and histological and appearances were measured using clinical response and histological grading scores.

RESULTS

Complete or almost complete clearance of pigmentation with minimal residual histological evidence of LM was observed in four patients, one patient showed no clinical or histological improvement, and the remaining patient had almost no residual pigmentation clinically after treatment yet histopathological changes remained as severe as before treatment.

CONCLUSIONS

Topical imiquimod cream merits further investigation as a new therapy for LM.

An update and guidance on narrowband ultraviolet B phototherapy: a British Photodermatology Group Workshop Report

Summary These guidelines for use of narrowband (TL-01) ultraviolet B have been prepared for dermatologists by the British Photodermatology Group on behalf of the British Association of Dermatologists. They present evidence-based guidance for treatment of patients with a variety of dermatoses and photodermatoses, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of background photobiology.

Can a positive photopatch test be elicited by subclinical irritancy or allergy plus suberythemal UV exposure?

Photopatch test (PhPT) interpretation is difficult and clinical relevance is not always apparent. A positive PhPT may reflect photocontact allergy or phototoxicity. We hypothesized that it may also reflect the additive or synergistic effects of a suberythemal reaction to a contact irritant [e.g. sodium lauryl sulfate (SLS)] or allergen (e.g. nickel) and suberythemal UV exposure. 10 nickel allergic volunteers had duplicate SLS and nickel series applied on either side of the back for 24 h and 48 h, respectively. After removal, one side was irradiated with 5 J/cm(2) UVA or the dose below the minimal erythema dose for solar-simulated radiation (SSR). The minimal irritancy dose (MID) for SLS and the minimal allergenic dose (MAD) for nickel were determined visually and objectively by erythema meter. While photoaugmentation of subclinical contact allergy or irritancy occurred in some subjects, photosuppression occurred in roughly an equal number. UVA changed the nickel MAD at 48 h in 2 of 5 volunteers but not the SLS MID. SSR changed the nickel MAD in 4 of 5 and the SLS MID in 3 of 5. 2 subjects (none after UVA) showed erythema only in the irradiated set of patches, which could have been interpreted as a positive PhPT. We have demonstrated photoaugmentation and photosuppression of contact allergy and irritancy, which could result in false-positive or false-negative interpretation of PhPTs.

The optimal time to determine the minimal phototoxic dose in skin photosensitized by topical 8 methoxypsoralen

BACKGROUND

We recently investigated the characteristics of psoralen plus ultraviolet (UV) A erythema in skin photosensitized by topical 8-methoxypsoralen (8-MOP) in three independent studies.

OBJECTIVES

In order to determine the optimal time to read the minimal phototoxic dose (MPD) after treatment with topical 8-MOP and irradiation with UVA, we assessed the overall data.

METHODS

One forearm of each subject was immersed in 8-MOP solution for 15 min and test sites on the flexor surface of the forearm were immediately exposed to a UVA dose series. Erythema was assessed visually and objectively using a reflectance instrument at 24-h intervals for 7 days.

RESULTS

Results were obtained from 44 subjects (predominantly Fitzpatrick skin phototype II). A broad erythemal plateau was evident beyond 72 h and the visual MPD was significantly lower at 96, 120 and 144 h than at 72 h (P < 0.01). Only 30% of subjects were at peak erythema at the conventional MPD assessment time of 72 h. The median time to reach maximal erythema was 96 h (range 48-144). Objectively, 85% of subjects were at peak erythema at or beyond 96 h.

CONCLUSIONS

We recommend that (i) the optimal time to read the topical 8-MOP MPD is 4 days after UVA exposure as readings beyond this time may be difficult to interpret because of the development of pigmentation, and (ii) 40% of the topical 8-MOP MPD should be considered for the first treatment.

History of psoriasis response to sunlight does not predict outcome of UVB phototherapy

We prospectively asked 146 consecutive patients starting narrow-band UVB (NB-UVB) for psoriasis about the effects of sunlight on their psoriasis. Eighty-eight (60%) patients reported improvement with sunlight, six (4%) reported worsening, and 52 (36%) had not noted any change in their psoriasis with sunlight exposure. Overall, 101 (69%) were recorded to reach clearance or minimal residual activity (MRA), 24 (16.5%) to achieve moderate improvement, and 21 (14.5%) had other recorded outcomes (mainly 'did not attend'), with UVB phototherapy. Forty-two (72%) of the 58 who did not report improvement with sunlight went on to clearance/MRA with UVB compared to 59/88 (67%) of those who did report improvement (95% confidence interval for difference in percentage improving, -10% to 20%, P = 0.49). Patients' replies to questions about how their psoriasis responds to sunlight do not appear to predict response to UVB phototherapy in our patient population.

A randomized controlled trial (volunteer study) of sitafloxacin, enoxacin, levofloxacin and sparfloxacin phototoxicity

BACKGROUND

Fluoroquinolone antibiotics (FQs) are associated with phototoxic skin reactions following exposure to sunlight.

OBJECTIVES

We aimed to compare the phototoxic potential of sitafloxacin, a novel FQ with three others: sparfloxacin, enoxacin, levofloxacin and placebo in Caucasian volunteers. In a second study, two dosage regimens of sitafloxacin were compared with placebo in Oriental subjects.

METHODS

Randomized, placebo-controlled, assessor-blinded clinical trial. In 40 healthy Caucasians, sitafloxacin 100 mg twice a day (n = 8), sparfloxacin 200 mg day-1 (n = 8), enoxacin 200 mg three times a day (n = 8), levofloxacin 100 mg three times a day (n = 8) and placebo (n = 8) were given in oral doses for 6 days. In the second study, sitafloxacin 50 mg and 100 mg, both twice daily, were compared with placebo in 17 healthy Oriental subjects. Using an established monochromator technique, baseline threshold erythema levels were established pre-drug and on-drug. The phototoxic index (PI) baseline, minimal erythema dose (MED) divided by on-drug MED for each medication at each wavelength was determined and related to sitafloxacin peak plasma levels. The duration of susceptibility to phototoxicity was assessed by repeat phototesting daily after stopping medication.

RESULTS

In the Caucasian study, sitafloxacin 100 mg twice a day produced mild ultraviolet (UV) A-dependent phototoxicity (median PI = 1.45) at 365 +/- 30 nm (half-maximum bandwidth), maximal at 24 h with normalization by 24 h postdrug cessation. The sparfloxacin group experienced severe phototoxicity maximal at 24 h and, unusually for an FQ, extended in the visible region (430 +/- 30 nm), maximal at 400 +/- 30 nm (median PI = 12.35) with abnormal pigmentation at on-drug phototest sites lasting, although fading, for up to 1 year. Enoxacin showed UVA-dependent phototoxicity (335-365 +/- 30 nm) median PI 3.94 (at 365 +/- 30 nm) returning to normal 48 h after stopping the drug. Fading pigmentation at phototoxic sites also lasted up to 1 year. Phototoxicity was not detected in the levofloxacin or placebo groups. In the Oriental study, no clinically relevant phototoxicity was seen with either sitafloxacin or placebo groups.

CONCLUSIONS

We conclude that 100 mg twice a day sitafloxacin in Caucasians is associated with a mild degree of cutaneous phototoxicity. Enoxacin 200 mg three times a day and sparfloxacin 200 mg day-1 are much more photoactive. Sparfloxacin phototoxicity is induced by UVA and visible wavelengths. Levofloxacin and placebo failed to show a phototoxic effect. In the Oriental study, sitafloxacin 50 mg twice a day and 100 mg twice a day failed to demonstrate a clinically significant phototoxic effect.

A randomized, double-blind, placebo-controlled study of the efficacy of tetracaine gel (AmetopR) for pain relief during topical photodynamic therapy

BACKGROUND

Many patients find topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) painful. Local anaesthetics are not routinely used and their effect on PDT pain has not been examined.

OBJECTIVES

To evaluate the efficacy of tetracaine gel (Ametop) for pain relief during and after PDT.

METHODS

A prospective, double-blind, placebo-controlled study of 42 patients with lesions (< or =2 cm diameter) of superficial nonmelanoma skin cancer or dysplasia. Patients were randomized to either tetracaine (4% w/w) (n=22) or vehicle (n=20) gel under occlusion for 1 h pre-irradiation. Pain was assessed during and after irradiation using a visual analogue scale (VAS) and faces pain scale.

RESULTS

Patients who received tetracaine gel experienced only slightly less pain during PDT (median VAS 4) compared with those who received placebo (median VAS 4.5) (95% confidence interval for difference 0-3, P=0.08). No significant difference in pain was experienced between the treatment groups immediately after irradiation or later.

CONCLUSIONS

When compared with placebo, tetracaine gel did not significantly reduce pain during or after PDT for small lesions of superficial basal cell carcinoma, Bowen's disease or actinic keratosis.