ABSTRACT
Teledermatology is a useful tool in facilitating dermatology outpatient services since the advent of COVID-19. Assessment of lesions has become difficult to facilitate in large numbers. Teledermoscopy has been used for remote lesion assessment. However, the majority of teledermoscopy has been facilitated by healthcare professionals rather than the patient themselves (Vestergaard T, Prasad S, Schuster A et al. Introducing teledermoscopy of possible skin cancers in general practice in Southern Denmark. Fam Pract 2020;37: 513-18). Patients referred with lesions deemed to be low risk are now often initially assessed via telephone consultation in conjunction with photographs of the lesion. The majority of patients are subsequently called for dermoscopy. However, many of those referred have benign lesions and could be safely discharged if dermoscopy images of the lesion were available. Low-cost mobile dermoscopy attachments are available and have been marketed to patients for self-monitoring. We compared a smartphone-compatible dermoscopy device (Dermlite HUD) with traditional dermoscopic photography to assess the feasibility of using this device to photograph skin lesions. This device has equivalent magnification (x 10) to dermatoscopes, a smaller field of view (which in all lesions still allowed complete visualization) and employs polarized light. Dermoscopic photography using the Dermlite HUD was taken of 30 consecutive lesions over a 1-month period by dermatology registrars in the dermatology department. Lesions assessed included pigmented lesions, vascular lesions, nonulcerated skin cancers and benign lesions. Images were assessed by a consultant dermatologist and compared to dermoscopic photographs taken using the standard method employed in the department. Images were compared in terms of resolution, field of view and colour quality between the two instruments as per validated image analysis (Celebi M, Mendonca T, Marques J. Dermoscopy Image Analysis, 1st edn. Boca Raton, FL: CRC Press, 2015). The photographed lesions were assessed by a consultant dermatologist and compared with the standard method. Photos taken with the smartphone attachment were found to be 97% equivalent in terms of resolution, field of view and colour quality to those taken using the standard method and 29 of 30 were deemed suitable for remote lesion assessment. Low-cost smartphone dermatoscope attachments provide images of comparable quality to those taken with a dermatoscope and camera. This offers an opportunity to facilitate fully virtual assessment of low-risk skin lesions and is of use in patients unable to travel to clinics or during lockdowns to facilitate virtual clinics.
ABSTRACT
Perniosis is a vaso-occlusive phenomenon that features the formation of discrete erythematous papules, macules, nodules or patches. Perniotic lesions are induced by the cold and are symptomatic in terms of burning, pain or itching. Secondary complications such as overlying infections and ulceration may occur (Takci Z, Vahaboglu G, Eksioglu H. Epidemiological patterns of perniosis, and its association with systemic disorder. Clin Exp Dermatol 2012;37: 844-9). While most cases of perniosis are idiopathic, studies have shown a link between secondary perniosis, connective tissue diseases and haematological disorders. Paroxysmal nocturnal haemoglobinuria (PNH) is a haematological aberrant stem cell disorder. It is a very rare condition (1-1 5 cases per million population) and results in the death of approximately 50% of affected individuals as a result of thrombotic complications. Cutaneous sequelae are uncommon and may present as purpura due to dermal vein thrombosis (Zhao H, Shattil S. Cutaneous thrombosis in PNH. Blood 2013;122: 3249). To date, there have been no previously reported cases of perniosis as a cutaneous manifestation of PNH. A 42-year-old man, with a background of PNH and aplastic anaemia, presented with recurrent painful, erythematous macules and blisters along the palmar and plantar aspects of his fingers and toes. These lesions occurred over 4 years previously, coinciding with the diagnosis of PNH and aplastic anaemia. Physical examination revealed a solitary blistering lesion on the palmar aspect of his third right finger. In addition, there were multiple erythematous macules on the plantar aspect of the first and second toe of his left foot. A biopsy was performed. An autoimmune screen and antibodies for COVID-19 were all negative. Histopathological findings showed epidermal blister formation with the presence of some apoptotic keratinocytes admixed with superficial chronic perivascular inflammatory infiltrate. The inflammatory infiltrate was predominantly chronic lymphocytic and locally involved perieccrine glands noted to be underlying the blister formation, consistent with perniosis. The patient is currently awaiting treatment with eculizumab. This is a case of perniosis occurring as a cutaneous manifestation of PNH. Perniosis typically requires investigation for connective tissue diseases;however, we also warn dermatologists that perniosis could be a presenting feature of underlying paroxysmal nocturnal haemoglobinuria, a rare, life-threatening condition with a high mortality rate related to thromboembolism. This case highlights an interesting and previously unreported cutaneous manifestation of PNH.