Mats Bjellerup

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.

Pinch grafting of chronic leg ulcers in primary care: Fourteen years' experience

Pinch grafting for treatment of chronic leg ulcers has been evaluated mainly in hospitalized and immobilized patients. This study describes the results of 199 pinch graft operations of 126 chronic leg and foot ulcers in 85 patients in primary care between 1987 and 2001. The aetiology of the ulcers was venous insufficiency in 43% and multi-factorial in 25% (77% with venous insufficiency as the main determinant). The mean ulcer size was 13.5 cm2 and the mean ulcer duration was 15.9 months. The overall healing rate within 3 months was 33%, ranging from 19% for multi-factorial or combined venous and arterial ulcers to 48% for venous ulcers. Within 12 months the overall healing rate was 60%, with 67% healed venous ulcers. The results from our study suggest that pinch grafting is suitable for treating chronic leg ulcers, especially venous ulcers, in primary care.

Accuracy of Clinical Skin Tumour Diagnosis in a Dermatological Setting.

The aim of this study was to evaluate the accuracy of preoperative diagnosis of skin tumours in a dermatological setting. Patients undergoing skin surgery at the Department of Dermatology without preoperative biopsy were prospectively enrolled. Preoperatively, a single clinical diagnosis was registered. The histopathological diagnosis, performed after excision, was registered as the correct diagnosis. The sensitivity and positive predictive value of the clinical diagnosis were calculated. A total of 2,953 tumours were included. Altogether, 55.1% of the excised lesions were malignant. Excision margins for malignant tumours were free from tumour cells in 96.0% of cases. The sensitivity for diagnosis of malignant tumour was 98.0% and the positive predictive value was 85.3%. In line with previous studies, the sensitivity and positive predictive value were highest for basal cell carcinoma, 95.4% and 85.9%, respectively. For squamous cell carcinoma, the corresponding values were 68.0% and 67.3%, and for melanoma, 70.6% and 51.3%.

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.

Excision of lipodermatosclerotic tissue : An effective treatment for non-healing venous ulcers

In longstanding venous ulcers, the development of lipodermatosclerosis of the skin surrounding the ulcer is common. According to our clinical experience lipodermatosclerosis impairs the opportunities for the ulcer to heal. In this combined retrospective and prospective study the lipodermatosclerotic skin area was excised in 7 non-healing venous ulcers and then covered with split skin graft. All 7 legs had previously been treated with superficial venous surgery. Laser Doppler scanning of the ulcer area was performed pre- and postoperatively. Five of the 7 ulcers healed within 4 months and 1 healed within 9 months. Laser Doppler scanning showed increased blood flow in the lipodermatosclerotic skin area, which was decreased after the operation. This study indicates that excision of the lipodermatosclerotic skin area followed by split skin grafting can accomplish healing in non-healing venous leg ulcers that have failed to respond to previous superficial venous surgery.

Preoperative prediction of histopathologic outcome in basal cell carcinoma - flat surface and multiple small erosions predict superficial basal cell carcinoma in lighter skin types.

Prediction of the histopathological subtype of basal cell carcinoma (BCC) is important for tailoring optimal treatment, especially in patients with suspected superficial BCC (sBCC).

Diagnosis of Pigmented Skin Tumours in a Dermatological Setting: Different Aspects of the Number Needed to Excise as a Measure of Efficiency

The increasing incidence of melanoma prompts a need for efficient management of this patient group. In this study, we use the number needed to excise (NNE), as a measurement of the efficiency of diagnosing melanoma. From January 2009 to December 2012, postoperative records from all patients were prospectively registered. All excised tumours with the histopathological diagnosis of naevus, melanoma or seborrhoeic keratosis were included. NNE values, both excluding and including seborrhoeic keratosis, changes over time, as well as patient- and tumour-related factors influencing NNE were determined. In total, 1,717 cases were included. The overall NNE value was 6.5, and the value fell significantly (ru2009=u20090.959, pu2009=u20090.041) during the 4-year study period from 8.2 to 4.8. NNE values decreased with increasing patient age to 1.8 in patients ≥u200980 years of age. The overall NNE value including seborrhoeic keratosis was 6.8.

The role of vascular surgery in chronic leg ulcers: report from a specialized ulcer clinic.

Experience gained from cooperation between dermatologists and vascular surgeons in 177 patients evaluated at a joint leg ulcer clinic is reported. Patients were divided into two subgroups: (i) 86 patients with healed ulcers and (ii) 91 patients with ongoing therapy-resistant ulcers. Venous insufficiency was the most common etiology in both subgroups (87% and 55%, respectively). Of previous therapy-resistant ulcers, 71% were healed after the combined effort. The pattern of venous incompetence differed between the two subgroups; patients with isolated superficial disease constituting 68% and 26% of patients, respectively. In patients with therapy-resistant ulcers, those with isolated superficial venous insufficiency were found to have a better prognosis than those with deep venous insufficiency. Cooperation between the dermatologist and vascular surgeon is a mainstay in order to take advantage of the possibilities offered by modern vascular surgery.

Diagnostic agreement and interobserver concordance with teledermoscopy referrals

Malignant melanoma and non‐melanoma skin cancers are among the fastest increasing malignancies in many countries. With the help of new tools, such as teledermoscopy referrals between primary health care and dermatology clinics, the management of these patients could be made more efficient.

Validity of ABCD Rule of Dermoscopy in Clinical Practice.

The ABCD rule of dermoscopy was developed to facilitate the dermoscopic differentiation between benign and malignant melanocytic lesions. However, there is a lack of studies on its validity in clinical practice. The aim of this study was to evaluate the accuracy of the algorithm used bedside, compared with the accuracy of the preliminary preoperative diagnosis, and to rate physicians level of confidence in the diagnosis. Melanocytic tumours were preoperatively scored bedside, according to the ABCD algorithm; 309 cases (46 melanomas and 263 naevi) were included. A sensitivity of 83% and specificity of 45% were found for the ABCD algorithm. A comparable sensitivity (74%), but a significantly higher specificity (91%), was found for the preliminary diagnosis. Interestingly, there was a considerable percentage (19.6%) of early melanomas for which a malignant diagnosis was not preoperatively expected, indicating that it is important to maintain generous indications for excision or to practise short-term follow-up of ambiguous lesions in order to detect early melanomas.