Sun pain and solar dysesthesia: A new challenge in clinical practice

BACKGROUND

A few patients report intense pain and other unpleasant sensations, such as burning, dysesthesia and hyperalgesia, after even brief exposure to the sun and in the absence of any skin lesion. Sometimes they also develop systemic symptoms, such as mild fever, fatigue, faintness and fainting. As a result, these patients carefully avoid even short-term sun exposure with a consequent severe negative impact on their lives.

METHODS

We have reviewed the clinical findings and the results of photobiological investigations of 10 patients who presented this clinical picture. Six of these patients were previously described by our group with the diagnosis of sun pain. We have reviewed the similarities with other previously described disorders such as solar dysesthesia and PUVA pain and have evaluated possible pathogenetic mechanisms.

RESULTS

During phototesting our patients experienced intense pain in the exposed area and in the surrounding skin, without any visible lesion, even with very low sub-erythemal doses. At follow-up, five patients were diagnosed with fibromyalgia, three with a major depressive disorder, one with bipolar syndrome and one with a conversion disorder. The pathogenesis remains unclear, but the use of a psychopharmacological treatment with antidepressants improved both the neuropsychiatric symptoms and sensitivity to the sun in most subjects.

CONCLUSION

For patients with pain and other severe symptoms in the absence of skin lesions and clinical and laboratory manifestations of known photodermatoses, a neuropsychiatric evaluation should be suggested.

Algorithmic approach toward diagnosis of patients with congenital photosensitivity disorders and review of literature

The congenital photosensitivity disorders present as cutaneous signs and symptoms secondary to photosensitivity, extracutaneous manifestations, and a predisposition to malignancy. Diagnosis of these conditions mainly depend on clinical findings as the molecular analysis is not always feasible. A review of all the related articles collected after a thorough literature search using keywords, "congenital AND photosensitivity NOT acquired" and the individual diseases was done. A total of 264 articles were included in the review. An algorithm for diagnosis of the different congenital photosensitivity disorders based on the various clinical presentations has been proposed. An early suspicion and diagnosis of the different congenital photosensitivity disorders is the cornerstone behind prompt institution of prevention and treatment, and decreasing the associated morbidity.

JAK-ing up chronic actinic dermatitis with upadacitinib

We describe a unique and significant case of a 75-year-old man successfully treated with upadacitinib for chronic actinic dermatitis.

Equipment developed for simplifying routine phototesting in dermatology

Some people react abnormally when exposed to sunlight by getting easily burned or develop a rash. When testing a patient's level of photosensitivity in the clinic, the UVR dose to provoke erythema is determined by the minimal erythema dose (MED) test. Subsequently, a photoprovocation test is performed to detect abnormal skin reactions by daily exposing the skin to UVR for several consecutive days. Associated problems in MED testing include choice of an even skin area for testing, patients keeping still during the test, testing with different UVR doses simultaneously, and securing clear borders of erythema. To address these issues, a MED Test Patch was developed which adheres closely to the skin to ensure sharp erythema borders and provides six irradiation fields with decremental doses of 20%. For MED testing, we constructed a solar simulator and LED lamps with peak emissions at 309 and 370 nm, small enough to be mounted directly on to the MED Test Patch and accommodate patient movements. These lamps and a 415 nm LED can also be used for provocation testing which is best performed on the back where the skin is assumed to have identical UVR sensitivity, and the area is large enough for adjacent MED and provocation test fields. Reading of erythema is still performed by visual and tactile evaluation. The UVA and UVB MED test can be performed in 1 h. The advantage of these developments is an easy-to-use, standardized test method with improved accuracy of the results.

[Current problems of polypharmacy in geriatric patients when taking drugs with a risk of photosensitivity.]

The article presents an overview of the current problems of polypharmacy in geriatric patients when taking drugs with a risk of photosensitivity. The article contains information about emerging adverse drug reactions, as well as methods for diagnosing, correcting and preventing phototoxic and photoallergic reactions in patients of older age groups. The main aspects of dermatological support in the system of long-term care for geriatric patients when taking drugs with a risk of photosensitivity are outlined. Clinical signs of senile xerosis and skin manifestations of adverse drug reactions were studied when taking drugs with the risk of photosensitization before and after the use of a photoprotector in elderly patients.

Insights into proton pump inhibitor-induced photosensitivity: An observational study in a tertiary photobiology service

BACKGROUND

Proton pump inhibitors (PPIs) are extensively prescribed but may cause photosensitivity and drug-induced lupus erythematosus (DILE), which can be overlooked as the drug may have been taken for years prior to presentation.

METHODS

We reviewed the clinical and investigation findings of patients diagnosed with PPI-induced photosensitivity, diagnosed through the Scottish Photobiology Service.

RESULTS

We report 11 patients with median age of onset 61-years and mean duration of PPI ingestion of 5-years [DILE (n = 6), phototoxicity (n = 3) and drug-induced solar urticaria through a lupus mechanism (n = 2)]. Five had Anti-Ro antibodies (three also ANA positive). Predominantly UVA and visible light photosensitivity was observed on phototesting.

DISCUSSION

PPIs are a reversible cause of photosensitivity and DILE. Time to onset from drug initiation to symptoms can be prolonged, so clinicians should have a high index of suspicion in those taking PPIs. Most are diagnosed through clinical assessment and lupus serology, with phototesting indicated if there is diagnostic uncertainty.

Efficacy Of Methotrexate Versus Azathioprine In The Treatment Of Chronic Actinic Dermatitis: A Randomized Control Trial

BACKGROUND

Azathioprine is first line immunosuppressive agent in treatment of chronic actinic dermatitis. The role of methotrexate has been effective in different dermatosis and it seems reasonable to use it in the treatment of chronic actinic dermatitis.

AIMS

We sought to compare the efficacy of methotrexate versus azathioprine in treatment of chronic actinic dermatitis.

METHODS

Patients with chronic actinic dermatitis were randomized to receive methotrexate in group A and azathioprine in group B. The response to treatment in terms of percentage PASI reduction and side effects of medications were assessed 12 weeks follow-up.

RESULTS

In group A, the percentage PASI reduction was <25% in 2 (1.19%) patients, 25-49% in 47 (27.9%) patients, 50-74% was achieved by 35 (20.8%) patients while in group B, the percentage PASI reduction of 25% was achieved by 2 (1.19%) patients, 25-49% in 45 (26.7%) patients, 50-74% in 37 (22.0%) patients. More than or equal to 75 percentage PASI reduction was not achieved by any patient in the study. Both drugs were found efficacious in treatment of CAD. A total of 23 (27.38%) patients in group A and 22 (26.19%) patients in group B showed derangement in laboratory investigations during 12 weeks treatment. The limitation of study was inability to do photo-patch test, so patients were diagnosed clinically and biopsy was done in clinically challenging cases.

CONCLUSION

: This study shows that methotrexate is equally effective as azathioprine in the treatment of chronic actinic dermatitis with its added benefits of being cost effective and better safety profile.

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.

'More extraordinary than mundane … ' A phenomenological analysis of the experiences of individuals living with CLE and their taking care in the sun

Introduction

CLE is a chronic inflammatory autoimmune condition of which photosensitivity is a major symptom. Individuals living with CLE are advised to practice photoprotection. Despite the benefits for disease control, many individuals living with CLE do not practice optimal photoprotection. The aim of this study was to gain a deep insight into the lived experiences of individuals with CLE and their photoprotective practices.

Methods

A qualitative study approach was conducted, using Hermeneutic phenomenology. Individuals living with CLE were recruited and interviewed. Rich pictures were used to enrich the interviews. Interviews were transcribed and analysed using Template Analysis.

Results

Analysis revealed four themes: ‘Much more than just a photosensitive skin condition’, ‘The impact of sun on CLE and social dynamics’, ‘Drifting to the sun: personal transitions and social norms’ and ‘Taking care in the sun: easier said than done’.

Discussion and conclusion

This study provides a nuanced insight into the lived experiences of individuals with CLE and their photoprotective practices. Taking care in the sun is not a simplistic process. Beyond the biomedical model of illness, the social impact that CLE has on individuals has a dominant influence on their photoprotective behaviours. Such insights could help healthcare professionals tailor photoprotective advice.

Transient Pruritic Erythema as a Forme Fruste of Solar Urticaria

BACKGROUND

Solar urticaria (SU) is a rare and disabling photodermatosis. SU typically manifests as urticarial wheals and erythema appearing shortly after sun exposure. SU is often initially diagnosed clinically with subsequent confirmation through photoprovocation tests. Early diagnosis is important for correct management of patients.

OBJECTIVES

To present the clinical features of three cases of atypical presentation of SU and to discuss possible underlying mechanisms.

METHODS

We report a series of three patients who presented with transient pruritic erythema without wheals after sun exposure. All patients had photoprovocation tests conducted to confirm SU diagnosis and to determine their action spectra. Treatment outcomes were recorded.

RESULTS

All three patients developed classical manifestations of SU during photoprovocation tests within the UVA1 spectrum. Two patients required high-dose irradiation to provoke urticaria.

CONCLUSIONS

Erythema without urticaria can be the primary manifestation of SU, especially in countries with sunny climates where natural skin hardening is common. Such cases require a high index of suspicion for SU and highlight the importance of photoprovocation testing to confirm the diagnosis.

Photolichenoid dermatitis: a presenting sign of human immunodeficiency virus

Photolichenoid dermatitis is an uncommon eruptive dermatitis that often occurs in association with a photosensitizing drug. Photodermatitis, in general, is an uncommon clinical manifestation of human immunodeficiency virus (HIV), most often affecting patients of African and Native American descent. Photolichenoid dermatitis has infrequently been reported in patients with HIV who have not been exposed to a photosensitizing drug. We report a case of an African patient with a photodistributed depigmenting eruption without exposure to a photosensitizing drug. Histologic examination revealed a patchy perivascular and bandlike lymphocytic infiltrate with melanophages, interface changes, and dyskeratotic keratinocytes, consistent with photolichenoid dermatitis. Laboratory examination was significant for a positive HIV-2 antibody. Photolichenoid dermatitis may be a presenting sign of HIV infection and may not necessarily be associated with exposure to a photosensitizing drug. Testing for HIV should be done in patients who present with photodistributed depigmenting eruptions, even in the absence of exposure to a photosensitizing drug, and particularly in patients of African and Native American descent.

Incapacitating solar urticaria: successful treatment with omalizumab

Solar urticaria is a rare form of physical urticaria mediated by immunoglobulin E. The lesions appear immediately after the sun exposure, interfering with the patient's normal daily life. Omalizumab, a monoclonal anti-IgE antibody, has been recently approved for the treatment of chronic spontaneous urticaria, and the latest reports support its role also in the treatment of solar urticaria. Hereby, we report a case of solar urticaria refractory to conventional treatment strategies, with an excellent response to treatment with omalizumab and phototesting normalization.

Diagnostic Delay in Erythropoietic Protoporphyria

Erythropoietic protoporphyria is a photodermatosis presenting in childhood with severe pain on sun exposure. The diagnosis is often delayed because of the lack of awareness among pediatricians. We describe the diagnostic odyssey of 2 children presenting with symptoms of erythropoietic protoporphyria and report results of a survey of 129 affected individuals.

Recent Developments in the Diagnosis and Management of Photosensitive Disorders

Photodermatoses occur in males and females of all races and ages. Onset can be variable in timing and influenced by genetic and environmental factors. Photodermatoses are broadly classified as immunologically mediated, chemical- and drug-induced, photoaggravated, and genetic (defective DNA repair or chromosomal instability) diseases. Advances in the field have led to improved recognition and treatment of many photodermatoses. The purpose of this focused review is to provide an update on the diagnosis and management of a variety of photodermatoses, both common and less common, with review of recent updates in the literature pertaining to their diagnosis and management.

Expression of E-cadherin, syndecan 1, Ki-67, and maintenance minichromosome 3 in tissue lesions of actinic prurigo obtained by incisional biopsy

Actinic prurigo (AP) is an idiopathic photodermatosis; the initial manifestations usually occur during the first decades of life but can appear at any age. Cases are usually diagnosed late once the lesions have exacerbated; due to the extensive involvement of the vermilion border and the etiology, it has been confused with and related to a potentially malignant process. Syndecan-1 and E-cadherin were positive in the epidermis, with moderate-to-intense staining in 100% of samples. Ki67 and MCM3 were expressed in the lower third of the epidermis and showed greater immunolabeling in samples that contained lymphoid follicles (Ki 67: epidermis [17.7% ± 6.79%] and dermis [7.73% ± 6.69%]; MCM3: epidermis [22.92% ± 10.12%] and dermis [6.13% ± 6.27%]). In conclusión AP is a disease in which there is no evidence that the lesions are potentially cancerous. AP cheilitis should not be confused with actinic cheilitis because they are separate entities.

Systemic Lupus Erythematosus Presenting as Livedoid Vasculopathy over the Forearms

38-year-old married woman presented with multiple spontaneous painful ulcers that had involved both forearms for the previous month, along with a single episode of generalized tonic-clonic seizures, with no residual palsy or paresis. She complained of photosensitivity and diffuse hair loss for the past 6 months. She also had had arthralgia for the previous 3 years, which had initially involved the small joints of the fingers (especially the proximal interphalangeal joints) and gradually progressed to involve the larger joints. There was no history of recurrent oral ulcers, psychosis, thromboembolic events, or any other skin lesions. Two years previously, she had taken antitubercular treatment for pulmonary tuberculosis.

Kindler syndrome in a patient with colitis and primary sclerosing cholangitis: coincidence or association?

Kindler syndrome is a rare, autosomal recessive genodermatosis, caused by mutations in the FERMT1 gene. It is thought to be primarily a skin disease, but other organs may also be involved. We report a case of a novel mutation of FERMT1 gene in a patient with a probable new phenotype of Kindler syndrome, including colitis and primary sclerosing cholangitis. A 42-year-old man, born to first cousin parents, was referred to our outpatient dermatology clinic with an unknown dermatosis since birth. He presented with neonatal blistering and developed photosensitivity and changes in skin pigmentation during childhood. Since the age of 20, he has had regular follow-up in the gastroenterology clinic, owing to esophageal stenosis, ulcerative colitis, and primary sclerosing cholangitis. Clinical examination revealed jaundice, poikiloderma, diffuse cigarette paper-like atrophy on dorsal surfaces of the hands, and palmoplantar hyperkeratosis. Skin biopsy showed epidermal atrophy covered by orthokeratotic hyperkeratosis. DNA molecular analysis revealed FERMT1 homozygous mutation c.1179G&gt;A, p.W393X, which has not been reported before. The intestinal phenotype of Kindler syndrome has already been defined previously. However, to the best of our knowledge, no other case of primary sclerosing cholangitis in a patient with Kindler syndrome has been reported.

Efficacy of a Daily Protective Moisturizer with High UVB and UVA Photoprotection in Decreasing Ultraviolet Damage: Evaluation by Reflectance Confocal Microscopy

Patients with photodermatoses or actinic keratosis benefit from very high ultraviolet B-ultraviolet A (UVB-UVA) photoprotection. However, poor compliance is an issue that jeopardizes adequate protection, leading to disease recurrence. This study evaluated the efficacy of a daily protective moisturizer with high UVB and UVA photoprotection applied 8 h before irradiation. A monocentric, open-label, prospective, control pilot study was performed including 10 patients. Patients were irradiated with UVB and UVA before and 8 h after topical application of the product. Reflectance confocal microscopy (RCM) assessment was performed 24 h later. Clinical assessment showed a statistically significant increase in minimal erythema dose (MED) after application of the product (p <0.001). Signs of UV damage according to RCM were not observed on photoprotected skin (p <0.05). Skin irradiated 8 h after applying a daily protective moisturizer presented an increase in MED and RCM findings that equal the findings for non-irradiated skin.

Diagnostic Tools for Doctors' Evaluation of Tattoo Complications

Diagnosis of tattoo complications is a multi-facetted field since many clinical entities and disease mechanisms are represented. Infections, allergies, and pigment foreign body reactions with granuloma are the major groups. The clinician needs a structured approach to diagnosis and an armamentarium of standard tests. Diagnosis primarily builds on patient history, objective clinical examination, and punch biopsy, supplemented with microbiology testing, ultrasound scanning, and clinical photography. Evaluation of allergic tattoo reactions and allergy to pigments by patch testing is not applicable and has a falsely negative outcome except for the diagnosis of allergy to metals and preservatives. Simple inspection of raw punch biopsies from chronic tattoo reactions, preferably evaluated with stereo microscopy, provides important information about the density and the local distribution of tattoo pigment in the dermis and changes of micro- anatomical skin structures. Histology may show subtle structural changes, but traditional patterns (lichenoid reaction, pseudolymphoma, granuloma, and pseudoepitheliomatous epidermal hyperplasia) are of little or no help in the diagnosis since the patterns overlap and have no distinct clinical correlates. Histology cannot separate allergic and nonallergic reactions. However, granulomatous reaction and sarcoid granuloma are significant findings since papulonodular reaction of black tattoos and sarcoidosis are strongly associated with each other. 20-MHz ultrasound scanning is important for noninvasive imaging and characterization of inflammatory tattoo reactions and can be used preoperatively as guide to treatment. Electron microscopy can visualize pigment particles in tissues, cells, and tattoo inks. Chemicals of pigment in tissues and in tattoo inks can be analyzed by high-performance liquid chromatography, mass spectroscopy, and Raman spectroscopy.

Lupus erythematosus tumidus: an underestimated entity

There have been few reports of lupus erythematosus tumidus (LET) in the literature. Most of textbooks of dermatology or dermatopathology mention this entity only briefly, if at all. The authors describe an additional case of this underdiagnosed disorder that further supports its existence as a separate entity in the spectrum of the variants of chronic cutaneous lupus erythematosus. Although most cases are reported in the European countries, to our knowledge, this is the first case documented in Portugal. The clinical, photobiological and histological features as well as differential diagnosis, treatment and prognosis are also discussed.

Possible photoactivated dermatitis with features of post-inflammatory pigmentary alteration (PIPA) and rosacea

Cutaneous flushing and facial erythema are common dermatologic conditions that elicit a wide differential diagnosis that includes rosacea, seborrheic dermatitis, photodermatitis, connective-tissue diseases, carcinoid syndrome, and mastocytosis. Herein we present an usual case of a mask-like rosacea-PIPA overlap that occurred in a patient with prior history of rectal carcinoid tumor and a negative systemic evaluation.

Chronic actinic dermatitis occurring in an adult with atopic dermatitis

Chronic actinic dermatitis (CAD) is a photosensitivity disorder that is characterized by a persistent eczematous eruption in sun-exposed sites. The hallmark of CAD is a reduced minimal erythema dose (MED) to ultraviolet B (UVB), ultraviolet A (UVA), and/or to visible light, which makes phototesting the essential diagnostic investigation. The uncommon subgroup of patients with atopic dermatitis (AD) that are affected by CAD has primarily been described in young patients in the United Kingdom. We present an atopic adult women with CAD who was diagnosed years after symptoms began. We believe it is important that dermatologists perform phototests on AD patients with features of a photoaggravated dermatitis in order to avoid delay in diagnosis of a true photosensitivity condition and provide appropriate management.

Actinic Prurigo

Actinic prurigo is an idiopathic photodermatosis that affects the skin, as well as the labial and conjunctival mucosa in indigenous and mestizo populations of Latin America. It starts predominantly in childhood, has a chronic course, and is exacerbated with solar exposure. Little is known of its pathophysiology, including the known mechanisms of the participation of HLA-DR4 and an abnormal immunologic response with increase of T CD4+ lymphocytes. The presence of IgE, eosinophils, and mast cells suggests that it is a hypersensitivity reaction (likely type IVa or b). The diagnosis is clinical, and the presence of lymphoid follicles in the mucosal histopathologic study of mucosa is pathognomonic. The best available treatment to date is thalidomide, despite its secondary effects.

Dialysis-associated pseudoporphyria successfully treated with vitamin D. Report of two cases

Pseudoporphyria refers to a rare bullous dermatosis characterized by the clinical and histological features of porfiria cutanea tarda without abnormalities in porphyrin metabolism. The pathogenesis is heterogeneous and several exogenous factors may promote the bullous lesion formation, including medications, end stage renal disease, dialysis and tanning beds. Regarding treatment of this condition, in literature different therapy have been reported, such as glutathione and his precursor N-acetylcysteine, which presents anti-oxidant properties; however even more toxic drugs, such as chloroquine, are used. Moreover, in patients with drug-induced PP discontinuation of the offending agent, if possible, is a crucial aspect of the clinical management. We report two cases of dialysis patients presenting blisters on extremities, which healed with the avoidance of UV exposure and oral Vitamin D supplementation. Interestingly Vitamin D despite the lack of antioxidant properties led to a completely resolution of PP in both our patients within 30 days. A possible explanation of this finding is that Vitamin D, playing a key role in the regulation of serum Ca2+, can modulated cadherin-cadherin interactions and led to healing of pseudoporphyria bullous lesions. Finally we highlight the prominent role of UV-exposure in PP elicitation thus a good photoprotection is essential for all patients with pseudoporphyria.

Actinic prurigo

Actinic prurigo is a chronic photodermatosis with onset in childhood or before 20 years of age. It is most prevalent in Amerindians and Latin American mestizos, although it has been reported worldwide. Patients present with photodistributed, erythematous excoriated papules, cheilitis, and conjunctivitis. There is strong association with human leukocyte antigen DR4, especially the DRB1*0407 subtype. Treatment consists of photoprotection and the use of thalidomide.

Pigment protection factor as a predictor of skin photosensitivity--a Polish study

Assessment of individual photosensitivity by determining the minimal erythema dose (MED) is commonly accepted. MED objectively describes a single individual response to the irradiation of skin with a particular wavelength (UVB, UVA). Pigment protection factor (PPF) is an objective value to measure skin type. The aim of the project was to analyze PPF values in the population of Lodz and the relationship between PPF, skin phototype, and individual MED. The study was conducted on the group of 270 volunteers: 130 men and 140 women, mean age 28.5 years (OS + 9.66) with either skin phototype II or III, as defined by Fitzpatrick Skin Phototype Classification. Phototesting of each volunteer was undertaken with an increasing dose series (UVB radiation) on six squares (1×1 cm) on the skin of the back. The MED was defined as a perceptible erythema 24 hours later. Starting dose was determined by history, physical examination, and phototype ranged from 0.03-0.07 J/cm2. PPF was measured by a skin reflectance meter UV Optimize 555. The mean MED value was 0.15 J/cm2 and the PPF value was 6.15. A positive correlation between the MED value and PPF (R=0.38; P<0.001), and a positive correlation between phototype and MED and PPF (P< 0.001) were found. Both determination of MED and PPF are objective methods of photosensitivity assessment, but PPF determination is an easy and non-invasive method.

[Pharmaceutical chemistry of drug-initiated photosensitivity]

The photosensitivity originated from drugs is a common problem in medical and pharmaceutical practice. It is of prominent importance in drug development and in regulatory issues. The photosensitizer effect of drug substances is determined by their chemical structures, and it mainly originates from aromatic chromophore systems and photo-dissociable bonds forming free radicals. The photodegradation may happen in many different types of chemical reaction pathways. Our aim is to demonstrate in this review the interrelations between structure and photodegradation. We show examples for the different reaction types, with drugs from different pharmacologic therapeutic classes. The in vivo chemical reactivity of photodegradates of pharmaceutical substances, the in vitro methods of investigation for testing photoreactivity and phototoxicity, and briefly the clinical tests for photosensitivity disorders are also discussed.

A Case of Photocontact Urticaria Induced by Photodynamic Therapy with Topical 5-Aminolaevulinic Acid

Photodynamic therapy (PDT) with topical application of 5-aminolaevulinic acid (ALA) is a promising new treatment option for the management of various cutaneous malignancies. Generally, topical ALA-based PDT has relatively insignificant adverse effects of transient character; these include itching, stinging or burning pain and slight to moderate erythema. We describe the first case of photocontact urticaria induced by topical ALA-based PDT for the treatment of unilesional mycosis fungoides. Although the first treatment session resulted merely in mild erythema, the second PDT caused marked urticaria corresponding to the PDT-applied area with an intolerable stinging sensation. A photopatch test demonstrated that black light and visible light irradiation after topical ALA provoked an urticarial reaction in the patient's uninvolved skin. These observations suggested an allergic pathogenesis for the wheal formation induced by PDT with topical ALA in this case. Photocontact urticaria should be considered as a possible adverse effect in ALA-based PDT.

The Successful Use of Topical Tacrolimus Treatment for a Chronic Actinic Dermatitis Patient with Complications of Idiopathic Leukopenia

Chronic actinic dermatitis (CAD) is a photosensitivity disorder marked by severe eczematous lesions on exposed areas. Although associations with contact dermatitis, atopic dermatitis, and human immunodeficiency virus (HIV) have been suggested, its pathogenesis remains unknown. CAD is often refractory, and systemic administration of cyclosporin A has been the treatment of choice. Recently, topical tacrolimus therapy has been reported to be effective. We report the efficacy of topical tacrolimus treatment in a CAD patient who also had the complication of idiopathic leukopenia. A phototest showed marked suppression of erythema formation in the skin pre-treated with tacrolimus before UVB radiation but not in the skin treated after the irradiation. Therefore, it is suggested that tacrolimus may prevent UV-B induced erythema by suppressing a very early phase of the inflammatory process in CAD.

UVB-sensitive solar urticaria possibly associated with terbinafine

Solar urticaria is an uncommon condition characterized by erythema and whealing shortly after exposure to ultraviolet (UV) and/or visible light. We report a 25-year-old woman with an erythematous, edematous, pruritic reaction minutes after sun exposure while she was taking terbinafine for onychomycosis. Phototesting revealed a UVB-sensitive urticarial reaction, confirming the diagnosis of solar urticaria. This report describes the first patient with possible terbinafine-associated solar urticaria.

[Normal and abnormal skin color]

The varieties of normal skin color in humans range from people of "no color" (pale white) to "people of color" (light brown, dark brown, and black). Skin color is a blend resulting from the skin chromophores red (oxyhaemoglobin), blue (deoxygenated haemoglobin), yellow-orange (carotene, an exogenous pigment), and brown (melanin). Melanin, however, is the major component of skin color ; it is the presence or absence of melanin in the melanosomes in melanocytes and melanin in keratinocytes that is responsible for epidermal pigmentation, and the presence of melanin in macrophages or melanocytes in the dermis that is responsible for dermal pigmentation. Two groups of pigmentary disorders are commonly distinguished: the disorders of the quantitative and qualitative distribution of normal pigment and the abnormal presence of exogenous or endogenous pigments in the skin. The first group includes hyperpigmentations, which clinically manifest by darkening of the skin color, and leukodermia, which is characterized by lightening of the skin. Hypermelanosis corresponds to an overload of melanin or an abnormal distribution of melanin in the skin. Depending on the color, melanodermia (brown/black) and ceruloderma (blue/grey) are distinguished. Melanodermia correspond to epidermal hypermelanocytosis (an increased number of melanocytes) or epidermal hypermelanosis (an increase in the quantity of melanin in the epidermis with no modification of the number of melanocytes). Ceruloderma correspond to dermal hypermelanocytosis (abnormal presence in the dermis of cells synthesizing melanins) ; leakage in the dermis of epidermal melanin also exists, a form of dermal hypermelanosis called pigmentary incontinence. Finally, dyschromia can be related to the abnormal presence in the skin of a pigment of exogenous or endogenous origin.

A tale of two EEGs - Photic driving or photoparoxysmal discharge

A 29-year-old woman has a history of developmental delay and focal segmental glomerulosclerosis resulting in kidney failure. She underwent renal transplant which unfortunately failed, and is on hemodialysis as well as immunosuppression including tacrolimus. She was recently hospitalized for urosepsis requiring intensive treatment with vasopressors and multiple antibiotics. Soon after discharge, she was noted to have unstable gait, multifocal twitches, falls, and very brief episodes of staring or inattentiveness. She was readmitted. Her head CT was normal and lumbar puncture was negative. A bedside EEG was requested and showed an unusual response during photic stimulation.