Severe disabling Köebnerizing ulcerated necrobiosis lipoidica successfully managed with topical PUVA

Sir, We describe a severely disabled diabetic patient with Kübnerizing ulcerated necrobiosis lipoidica (NL), responding to treatment with topical PUVA. A 72‐year‐old male was referred to the dermatology clinic with disabling ulceration of his feet. Three years previously he had developed erythematous plaques affecting both feet, similar in appearance to a plaque on his right knee that had remained unchanged for 20 years. Within a year of onset the plaques gradually enlarged and ulcerated. Ulceration was associated with recurrent infections, deterioration in glycaemic control and disabling pain. The discomfort was so severe that he could no longer walk; he became housebound and unable to continue his favourite hobby of ballroom dancing. The patient even raised the possibility of having an amputation. In the year prior to seeing a dermatologist he required three hospital admissions; on each occasion he was treated with surgical debridement, intravenous antibiotics and insulin. Numerous courses of oral antibiotics were administered as an outpatient. Our patient has had diabetes for 5 years and prior to the onset of these ulcerated lesions, had required oral hypoglycaemics only. He has no other complications of diabetes. Examination revealed several well‐demarcated smooth shiny erythematous plaques with central atrophy and superficial ulceration on both feet and the right knee. The plaques on the feet were at sites where his shoes would rub. There was no neuropathy and no radiological evidence of osteomyelitis. Histology showed palisading granuloma in the mid‐dermis characterized by a central amorphous acellular area surrounded by lymphocytes, epithelioid histiocytes and numerous giant multinucleated cells, confirming the clinical diagnosis of NL. In view of the limited and potentially harmful therapeutic options available for the treatment of NL, we decided to treat the lesions with topical PUVA. The patient was treated twice weekly. Each treatment involved the application of 4·2 µL cm−2 8‐methoxypsoralen gel to the plaques 15 min before exposure to UVA. The initial dose of UVA was 0·25 J cm−2 and this was increased by regular increments of 0·1–0·25 J cm−2. After only three treatments there was a marked reduction in pain; all analgesics were stopped and he was able to walk comfortably. Further treatments led to healing of the ulceration and return to normal skin texture (Fig. 1). Over a period of one year the patient received 47 treatments with a cumulative UVA dose of 171·75 J cm−2. The plaques receded from an area of 212−112 cm2, a total reduction of 47%. Two plaques completely cleared. Our patient was once more able to dance and the improvement has continued a year after therapy was stopped. Following treatment with topical PUVA there was healing of all the ulcers and a return to the normal skin texture. (a) Before treatment; (b) after 20 treatments. The isomorphic (Köebner) response describes the development of a lesion in previously normal skin that has been traumatized. Although initially described in psoriasis by Köebner, a number of dermatoses display the phenomenon, including NL.1 It is thought that the increased production of collagen instigates the response in NL.2 Despite the clinical impression that this response in NL is not uncommon, a review of the literature found only seven documented cases (Table 1).1–7 In all seven cases NL occurred within scar tissue, all except one case being within postsurgical scars. Documented cases of NL Documented cases of NL Ulceration occurs in 30% of lesions of NL.8 Epidermal atrophy and anaesthesia9 predispose to ulceration, which commonly follows minor trauma. Ulceration is associated with a risk of infection, pain and significant disability, and is particularly resistant to treatment.10 In the study by Muller and Winklemann, four patients underwent amputation as a result of complications from persistent ulceration.8 PUVA has been successfully used for the treatment of superficial disseminated granuloma annulare (GA),11 a condition that has many features in common with NL,12 and has been used successfully to treat other unusual disabling ulcerations of unknown aetiology.13 We believe the dramatic reduction in pain was due to either the antibacterial effect of PUVA,14 or through the inactivation of inflammatory cytokines. In our case topical PUVA led to rapid healing of the infected ulcers and a dramatic improvement in quality of life.