Achenbach syndrome: no need for skin biopsy

Dear Editor As dermatologists with Achenbach syndrome (AS), we read with alarm the recent article in Clinical and Experimental Dermatology by Harnarayan et al. advocating skin biopsy in this condition. We agree with the previous paper by Mizuno et al. that the clinical presentation is diagnostic, with no need for invasive investigations such as angiography and skin biopsy. Furthermore, histology is likely to be indistinguishable from that seen in a simple bruise. Although ectatic capillaries have been observed, we found no corroborating reports of this finding, which is not required to reach the diagnosis. The presentation of the condition in CM is typical with onset in middle age of acute episodes of tingling followed by blue discolouration and swelling localized to a single finger (Fig. 1). Bruising may spread along the finger and usually resolves within 2–3 days. Episodes occur 1–5 times per year, usually provoked by prolonged pressure, such as carrying a suitcase to a dermatology congress in cold weather. This has been a consistent pattern for the first author (CM) over 30 years with no associated morbidity, apart from two episodes of spontaneous subconjunctival haemorrhage, which was also reported in a previous case but is not uncommon and might be coincidental. The presentation in the second author (SNC), previously described in this journal, is similar, but the features of male sex and childhood onset are more unusual. In typical cases, the results of vascular and haematological investigations are invariably normal. A genetic component, first suggested by SNC, is likely with possible autosomal dominant transmission. Because AS episodes are transient they are rarely witnessed in the dermatology clinic. However, the presentation can be alarming to patients, and we wish to raise awareness among clinicians of the benign nature of this disorder to spare fellow sufferers from unhelpful and unnecessary skin biopsy.