Bo Ljunggren

Differences in phototoxic potency should be considered when tetracyclines are prescribed during summer-time. A study on doxycycline and lymecycline in human volunteers, using an objective method for recording erythema.

Summary In order to test the phototoxic potency of the two tetracyclines most frequently prescribed in Sweden, a double‐blind cross‐over study using a double‐dummy technique with doxycycline 0·1 g twice daily. lymecycline 0·6 g twice daily, and placebo, was performed in 15 healthy volunteers. Drugs were given for 3 consecutive days, and on the third day volunteers were tested with 25, 50, 75 and 100 J/cm2 of artificial long‐wave ultraviolet radiation (UVA), and assessed 6 h later for erythematous photoreactions. Objective readings were made using skin reflectance spectrophotometry. All three substances were tested in each individual at weekly intervals. Within 50, 75 and 100 J/cm2 of UVA. lymecycline showed a slight increase in erythema compared with placebo, but this was not significant (50 and 100 J/cm2), or was of low significance (75 J/cm2). However, with the same doses, doxycycline showed a substantial increase in erythema compared with placebo, which was highly significant. We conclude that doxycycline has a higher phototoxic potency than lymecycline, and this is in agreement with earlier in vitro experimental data. We recommend that therapy with doxycycline is avoided during summer‐time, and during holidays in a sunny climate.

Reflectance spectrophotometry in the objective assessment of dye laser‐treated port‐wine stains

At present, the treatment of choice for congenital capillary malformations of the port‐wine stain type (PWS) is the flashlamp pulsed dye laser. Good results can be obtained in the majority of patients with this technique, but there is a group of poor responders. In the search for predictive tools to determine the therapeutic outcome, we have used a new photoelectric reflectance instrument.

The scandinavian multicenter photopatch study. Preliminary results

The Scandinavian photopatch test procedure has been applied to 745 patients with suspected photodermatoses during the years 1980‐1981. Our experience has been encouraging with the recording of several relevant reactions. A total of 132 positive photocontact reactions and 120 ordinary contact reactions Were seen. Photocontact reactions to musk ambrette (19 cases) and PABA (19 cases) were surprisingly frequent. The next most common photocontact reactions were to promethazine (24). chlorpromazine (22 cases and fentichlor (12). Ordinary contact reactions were observed to balsam of Peru (30). PABA (23), lichen mix (21), wood mix (14) and to perfume mix (10).

Psoralen photoallergy caused by plant contact

A case of acquired photocontact allergy to furocumarins in plants is reported. Photopatch testing was performed with four psoralens [8‐melhoxypsoralen (8‐MOP), 5‐methoxypsoralens (5‐MOP), trimethylpsoralen (TMP) and imperatorin (IMP)]. The use of serial dilutions of the test compounds made it possible to differentiate between photoallergic and phototoxic reactions. 8‐MOP gave a positive eczematous text reaction down to a concentration of 0.0001% The reactions to 5‐MOP and IMP also were positive, while that to TMP was negative. Histopathological examination of a biopsy specimen from a positive test site showed changes consistent with photoallergic contact dermatitis.

Narrowband ultraviolet B three times per week is more effective in treating vitamin D deficiency than 1600 IU oral vitamin D-3 per day: a randomized clinical trial

Background  It is known that narrowband ultraviolet B (NB‐UVB) radiation and oral vitamin D3 supplementation can both improve serum levels of vitamin D, expressed as 25‐hydroxyvitamin D3 [25(OH)D3]. However, surprisingly few studies have compared the effects of the two interventions in treating vitamin D deficiency.

A case of photosensitivity and contact allergy to systemic tricyclic drugs, with unusual features

A 43‐year‐old farmer on tricyclic antidenressive drugs developed a severe photodermatitis with associated liver involvement. The lesions spread to covered areas or the skin, suggesting photoallergy clinically. Patch and photopatch testing revealed photoallergy and contact allergy to clomiprumine and contact allergy also to carbamazepine. In addition, the patient had positive patch test reactions to chlorpromazine, balsam of Peru and fragrance‐mix, as well as a positive photopatch test to fentichlor. UVA and UVB erythema thresholds were normal. In this patient, an initial episode of photosensitization, probably elicited by clomipramine, was accompanied by contact allergy to this drug and to carbamazepine. The contact sensitivity to clomipramine could also be elicited by oral provocation without UV light. Hypothetically, a photoproduct of clomipramine may have been the original sensitizer, this compound subsequently cross‐reacting with clomipramine and, possibly with carbamazepine.

Influence of corticosteroids on ultraviolet light erythema and pigmentation in man.

SummaryTopical hydrocortisone and betamethasone-17-valerate were tested in alcoholic solution in human skin for their influence on a developing ultraviolet light erythema. Although the normal response was augmented by the ethanol vehicle, both drugs, applied before exposure, inhibited the erythema induced by irradiation of the sunburn range (UVB). They did not inhibit a phototoxic erythema induced by 8-methoxy-psoralen and long-wave irradiation (UVA). The pigmentation caused by the UVA exposure also appeared after UV stimulation which was too weak to evoke erythema.ZusammenfassungAuf die Haut aufgelegte alkoholische Lösungen von Hydrokortisonacetat und Betamethason-17-valerat wurden wegen einer eventuellen Einwirkung auf das ultraviolette Erythem in homo untersucht. Beide Substanzen, vor der Lichtexposition aufgetragen, zeigten eine Hemmung des Sonnenbranderythems (UVB). Ein phototoxisches Erythem, ausgelöst durch 8-Methoxypsoralen und langwellige UV-Strahlung (UVA) wurde dagegen nicht beeinflußt. Die Pigmentierung im UVA-Versuch war auch bei kurzen UV-Belichtungen, die kein Erythem hervorriefen, deutlich.

Systemic contact dermatitis from ethylenediamine in an aminophylline preparation presenting as the baboon syndrome

Sir, Systemic contact dermatitis is a delayed hypersensitivity reaction in the skin after systemic exposure to a substance to which the person has a contact allergy. The baboon syndrome is a specific, clinical presentation of systemic contact dermatitis involving the buttocks and surrounding skin (1). Systemic contact dermatitis from ethylenediamine (EDA) in aminophylline given i.v. presenting as the baboon syndrome has been reported once (2). We present a second case.

Experimental studies on the mechanism of benoxaprofen photoreactions

SummaryBenoxaprofen (BP), a non-steroidal antiphlogistic drug causing skin and nail photoreactions, has been evaluated for photoactivity using three experimental techniques. In vivo in the mouse, BP was phototoxic in doses of 25 mg/kg in combination with UV-A 54 J. The phototoxic potency could be confirmed in vitro with the Candida albicans test. In vitro, using photohemolysis, BP showed a dose-dependent activity causing 40% hemolysis at a concentration of about 25 μg/ml with UV-a. Also, small UV-B doses caused red cell lysis with a moderate BP concentration. Preirradiation experiments showed that UV-A, but not UV-B, photoproducts could account for some of the activity. The action spectrum of BP photoactivity lies mainly in the UV-A, but may also extend into UV-B. Compared with chlorpromazine in vivo and in vitro, and with doxycycline in vivo, BP showed intermediate phototoxic activity.

Contact dermatitis to estradiol benzoate

Three patients developed facial dermatitis after contact with preparations containing estradiol benzoate. Patch tests were positive to estradiol henzoate 0.1% in MEK but negative to other related estrogens including estradiol. All three patients also had positive tests to resorcinol monobenzoate and two out of three to balsam of Peru.