Pattern analysis of photopatch test reactions

In a multicenter study, photopatch test results from more than 1500 patients were evaluated between 1985 and 1990 and from 614 patients between 1990 and 1992. Photopatch testing was conducted according to a standardized procedure. Nearly half of the photoreactions were unclassifiable according to the classic definitions of photoallergic or phototoxic reactions. To facilitate the interpretation of these remaining photopatch test reactions, we developed a computerized substance specific reaction pattern analysis. By sequential readings from immediately after irradiation up to 72 h later and by morphological qualification of the reactions, the time course and morphological changes of each individual reaction were monitored. The summation of each individual photoreaction resulted in an overall reaction pattern of a specific substance. Four main categories could be distinguished. The first category was characterized by a peak immediately after irradiation followed by a descrescendo reaction. The second category comprized reactions combining an immediate with a delayed reaction. The third category exhibited a plateau-like delayed reaction. The fourth category showed delayed reactions in a crescendo pattern. Whereas category 1 represents classic phototoxic and category 4 classic photoallergic reaction patterns, the underlying mechanisms of categories 2 and 3 remain to be investigated. Typical substances of category 1 were many of the tested systemic drugs, such as furosemide, most of which are well-known phototoxic agents. Disinfectants, nonsteroidal anti-inflammatory agents and phenothiazines showed the reaction patterns of categories 2 and 3. A delayed type reaction (category 4) could be demonstrated for well-known photoallergens such as fenticlor, musk ambrette, and ultraviolet adsorbents in sunscreens.(ABSTRACT TRUNCATED AT 250 WORDS)

[Photochemotherapy (PUVA) of acute graft-versus-host disease]

For several years, psoralen and UV-A light (PUVA) therapy has been used in the treatment of chronic graft-versus-host disease (GvHD) following allogeneic bone marrow transplantation (BMT). There is little experience with PUVA treatment of acute GvHD. Allogeneic BMT was performed in 25 patients, 10 of whom developed acute GvHD despite immunosuppressive therapy. Six patients with acute cutaneous GvHD grade II-III (n = 2 grade II, n = 4 grade III) were treated with PUVA. We present the results. All the PUVA-treated patients improved markedly after 5-12 sessions of irradiation. In 5 patients the skin cleared completely with 8-18 treatments. In 4 patients chronic GvHD was prevented by maintenance treatment for up to 10 months. Following clearing of acute cutaneous GvHD, 2 patients developed chronic GvHD after therapy-free intervals of 3 and 12 months, respectively. These results indicate a beneficial effect of PUVA in acute cutaneous GvHD and suggest a protective effect against chronic GvHD.

[Lymphomatoid papulosis in a child]

We report a case of a 3-year-old boy who developed crops of papules and ulcerating nodules on the limbs in April 1992. Periodically, new lesions continue to erupt, while others resolve spontaneously. This course is characteristic for rhythmic paradoxical eruptions. This course and the clinical picture, supported by the histopathological and immunohistochemical findings, led to the diagnosis of lymphomatoid papulosis. Lymphomatoid papulosis is extremely rare in childhood. All published cases of lymphomatoid papulosis in children under 10 years of age are reviewed. The differential diagnosis of lymphomatoid papulosis in childhood includes arthropod assaults, pityriasis lichenoides et varioliformis acuta, primary cutaneous Hodgkin's disease, Ki-1 large cell anaplastic lymphoma and other lymphomas and pseudolymphomas in children.

Narrow-band UVB (311 nm) versus conventional broad-band UVB with and without dithranol in phototherapy for psoriasis

BACKGROUND

A narrow-band UVB lamp (Philips TL 01) emitting a peak of approximately 311 nm was developed to improve the phototherapy for psoriasis. Only a few studies have been performed with promising results.

OBJECTIVE

The therapeutic efficacy of the Philips TL 01 lamp in a new 100 W version was compared with conventional broad-band lamps (Sylvania UV 6) in a controlled trial.

METHODS

Twenty-three patients with psoriasis were treated with half-body exposures from the different UVB sources. The rate of clearing was monitored by estimation of the Psoriasis Area and Severity Index. All patients used emollients; excessive scaling was removed with salicylic acid in yellow petrolatum. In 13 patients dithranol in a modified Ingram regimen was added. In most cases the study was discontinued once a difference between the two sides was evident.

RESULTS

In 20 of 23 cases the TL 01 lamp proved to be significantly more effective than the conventional source. Application of dithranol provided a substantial additional therapeutic effect. With the high-intensity TL 01/100W bulbs, exposure times were comparable to broad-band UVB phototherapy.

CONCLUSION

The therapeutic efficacy of Philips TL 01/100W and its practicability for psoriasis phototherapy have been demonstrated.

Phototesting in lupus erythematosus

Ultraviolet (UV) irradiation is a major factor in the pathogenesis of certain variants of cutaneous lupus erythematosus. Photosensitivity constitutes one of the criteria of the American Rheumatism Association for the diagnosis of systemic lupus erythematosus, which further emphasizes its importance. The pathomechanism of UV-induced lupus erythematosus remains unknown. The characterization of photosensitive subacute cutaneous lupus erythematosus (SCLE) by Gilliam and Sontheimer has led to a new approach. Through the development of standardized test methods it has became possible to reproduce cutaneous lesions in the UV-A and UV-B spectrum. These standardized test methods allow a better definition of photosensitivity than clinical history does. Recent clinical data show that besides SCLE another variant, lupus erythematosus tumidus, also reveals pronounced photosensitivity. In this review article phototest procedures, phototest results, and clinical correlations in different subgroups are discussed.

[The effect of UV-A and UV-B irradiation on the skin barrier. Skin physiologic, electron microscopy and lipid biochemistry studies]

In order to gain insight into the effects of UV-irradiation on the skin barrier, functional (skin reactivity), electron microscopic and lipid-biochemical studies were performed. In three different irritation models, both UV-A-irradiated and UV-B-irradiated areas proved to be more resistant to damage than normal skin, providing evidence for improvement of barrier function after UV irradiation. Electron microscopic evaluation showed that UV-B induced a significant increase in horny cell layers, whereas after UV-A no change was detected. However, both UV-B and UV-A exposure resulted in an increase in the amount of all stratum corneum lipids. This was also observed in all major ceramide subfractions, which are believed to be the essential lipid constituents for the epidermal barrier function. These findings may explain the known beneficial effects of phototherapy in dermatoses with impaired barrier function, i.e., atopic dermatitis.

Photosensitivity induced by quinidine sulfate: experimental reproduction of skin lesions

A case of quinidine sulfate-induced photodermatitis is reported. The photosensitive reaction to quinidine sulfate was reproducible in the photopatch test and after oral intake plus ultraviolet A (UVA) irradiation. Eczematous dermatitis was provoked after intradermal injection of in vitro UVA-irradiated quinidine sulfate only in the presence of patient's serum. The clinical picture and histology suggest an allergic reaction. The photobinding of quinidine sulfate to a potential carrier protein in skin or serum seems to be of crucial importance for this type of photodermatitis. Quinidine sulfate is frequently used as an antiarrhythmic drug. Its potential as a photosensitizer should always be considered.

[Chronic actinic dermatitis. Concept and case examples]

Two women patients with chronic eczematous dermatitis, who also developed extremely severe, persistent photosensitivity during a course of 10 and over 40 years, are presented. Both patients had an atopic history with positive immediate skin reactions. Patch and photopatch tests revealed sensitization to several contact allergens, and in one case also a photocontact allergy. The action spectrum of the photosensitivity was confined to UV-B; it was possible to provoke eczematous skin reactions with doses smaller than 1 mJ/cm2 UV-B. Both patients were successfully treated with PUVA therapy. These case reports demonstrate the difficulty of nosological classification of chronic eczematous photosensitive dermatoses under the traditional terms persistent light reaction, photosensitive eczema, photosensitivity dermatitis, and actinic reticuloid. Chronic actinic dermatitis is defined clinically by chronic dermatitis on skin exposed to sun, histologically by spongiotic dermatitis, and photobiologically by experimental provocation of spongiotic dermatitis with UV-B and often also longer wavelengths in the absence of a photoallergen. Chronic actinic dermatitis should be used as a general term in addition to the more specific terms listed above.

[Erythropoietic protoporphyria: synopsis of 20 patients]

The authors present 20 patients (9 men, 11 women) with erythropoietic protoporphyria (EPP). The diagnosis was made on the basis of photosensitivity and porphyrin analysis. The disease first became apparent in the first years of life. The following acute symptoms were induced after exposure to sunlight: pruritus with or without skin changes, burning, pain and erythema, sometimes with petechiae, vesiculation and, in two cases, systemic symptoms. Chronic skin changes included hyalinosis cutis-like skin lesions, scarring, and also petechiae. Phototesting provoked only subjective symptoms, and none of the skin lesions characteristic of EPP could be induced. Postnatal diagnosis was attempted in three newborns, each of whom had one parent with proven EPP, by measuring the porphyrins in erythrocytes of cord blood. In all three normal porphyrin values were determined, and during an observation period of 3 years none has developed EPP. Therapy with carotenoids has yielded good to very good results in two-thirds of the patients. So far, a diagnosis of EPP has been established in 30 patients in Düsseldorf: one has died of liver cirrhosis and another has liver damage.

Influence of UV irradiation on the composition of human stratum corneum lipids

Irradiation with suberythemal doses of either UV-A or UV-B yielded an increase in the amount of stratum corneum lipids extracted from the lumbar skin area of 20 volunteers. These lipids were quantified after separation by high-performance thin-layer chromatography. Ten subfractions in the ceramide region were separated; two of them (fractions 7a and 7b) were only detectable after UV-A or UV-B irradiation. Improvement of barrier function after UV irradiation of human skin with suberythemal doses may be related to an increase in the stratum corneum ceramides.

Effects of ultraviolet A and B on the skin barrier: a functional, electron microscopic and lipid biochemical study

To investigate the effects of ultraviolet A (UVA) and B (UVB) on the skin barrier, functional, electron microscopic and lipid biochemical studies were performed on normal and UV-irradiated skin of volunteers. Skin reactivity against primary irritants was evaluated using the alkali resistance test, the dimethylsulfoxide test and the sodium lauryl sulfate test. In all 3 irritation models, UVA- and UVB-irradiated areas were more resistant to damage than normal skin, indicating improvement of the barrier function after UV irradiation. In a second series of experiments, biopsies were taken and processed for electron microscopic evaluation of the stratum corneum. UVB significantly increased the horny cell layers; UVA did not alter the thickness of the stratum corneum. Finally, stratum corneum lipids were extracted in vivo and quantified after high-performance thin-layer chromatography. UVB and, to some extent, UVA exposure increased the amount of all stratum corneum lipids. This was also observed in all major ceramide subfractions.

[Quinidine-induced photoallergy. A clinical and experimental study]

Photoallergies are type-IV allergic reactions of a special kind. Photoallergies due to quinidine sulphate were described as early as 1942. We present a case of quinidine sulphate-induced photodermatitis. The photoallergic reaction to quinidine sulphate was reproducible not only after oral intake but also in the photopatch test. In addition, an eczematous dermatitis was provoked after intradermal injection of quinidine sulphate previously exposed to UV-A irradiation in vitro together with serum taken from the patient. No dermatitis was seen with quinidine sulphate irradiated in the absence of serum. The binding of the hapten quinidine sulphate to a potential carrier protein in the serum seems to be of crucial importance in this type of photodermatitis. Quinidine sulphate is frequently used as an antiarrhythmic drug. Its potential photoallergenic action should always be considered.

[Animal experiment model of the effect of ultraviolet irradiation on hexachlorobenzene-induced porphyria]

The Effect of UV-Irradiation on the Hexachlorobenzene-induced Porphyria in an Experimental Animal Model Hexachlorobenzene is able to induce in humans and different animal species a hepatic porphyria, which is comparable to porphyria cutanea tarda. We studied whether hexachlorobenzene feeding could induce this porphyria also in hairless rats (Rowett-Nude), as these are suitable for photobiologic studies. After development of hepatic porphyria the rats were irradiated either with UV-A or UV-B light. Biochemical effects on the porphyrin metabolism and clinical as well as histologic skin changes were examined. In the liver of the porphyric rats, UV-A and UV-B irradiation induced increased aminolevulinic acid synthase activity accompanied with augmentation of hepatic porphyrin content. UV-A or UV-B irradiation also lead to increased total porphyrin contents in the skin of porphyric compared to non-irradiated animals. Clinically and histologically, however, only UV-A irradiation induced lesions, which were comparable to skin manifestations of porphyria cutanea tarda.

[Food hypersensitivity: skin test with commercial food extracts or natural products?]

In 46 patients with a suspected history of food allergy, we performed scratch tests using commercial food extracts (CF) in comparison with natural food products (NF). We found that NF brought about significantly stronger reactions than CF: 77% of the skin tests with NF were positive, whereas 75% of the tests with CF equivalents yielded negative or questionably positive results. We conclude, therefore, that in case of suspected food allergy, testing with CF only is not sufficient.

Experimental reproduction of skin lesions in lupus erythematosus by UVA and UVB radiation

Sunlight is a well-established factor in the induction and exacerbation of lupus erythematosus. Although experimental reproduction of lupus erythematosus lesions with wavelengths shorter than 320 nm was demonstrated previously, the effect of wavelengths longer than 320 nm was not investigated adequately. In this study we show that the action spectrum of lupus erythematosus reaches into the UVA region. A total of 128 patients with lupus erythematosus underwent phototesting with the use of polychromatic UVB and long-wave UVA. Subsets of the disease consisted of discoid lupus erythematosus (n = 86), subacute cutaneous lupus erythematosus (n = 22), and systemic lupus erythematosus (n = 20). Skin lesions clinically and histologically compatible with lupus erythematosus were induced in 64% of patients with subacute cutaneous lupus erythematosus, 42% of patients with discoid lupus erythematosus, and 25% of patients with systemic lupus erythematosus. The action spectrum of the induced lesions was within the UVB range in 33% of patients, in the UVA range in 14%, and in the UVB and UVA range in 53%. In positive test reactions patchy dark erythema and urticarial plaques developed within a few days. In some patients typical discoid lesions persisted for months.

[Photobiology of lupus erythematosus]

Photosensitivity is one of the criteria of the American Rheumatism Association for the diagnosis of systemic lupus erythematosus. Although UV irradiation is a major factor in the pathogenesis of photosensitive cutaneous lupus erythematosus, so far the exact pathomechanism is unknown. The following review presents historical, clinical and experimental data on the photobiology of cutaneous lupus erythematosus.

Health and social inequities in Switzerland

Despite standards of living and life expectancy amongst the highest in Europe, Switzerland exhibits fairly substantial social inequities in health. As regards male mortality by socio-economic group, these differentials are both marked and independent of cause of death. There is a wealth of information on morbidity and disability supporting the hypothesis that people in lower socio-economic groups tend to age faster and suffer more at younger ages. It is similarly evident that infants of low class mothers, particularly those unwed, underprivileged immigrant, are at excess risk. The Swiss results are of political and scientific interest in that they suggest that the average wealth of a community does not determine health differentials.