Acute vasculitis as a first manifestation of hairy cell leukemia

Skin changes in hairy cell leukemia

Skin lesions have been reported in about 10–12% of hairy cell leukemia (HCL) patients. Most are etiologically related to autoimmune or infectious processes, although secondary cutaneous neoplasms and drug-induced lesions are also reported. However, leukemia cutis with the direct infiltration of the skin by leukemic cells is extremely rare in HCL patients. This paper reviews the epidemiology, pathogenesis, clinical symptoms, diagnosis, and approach to treating skin lesions in HCL. A literature review of the MEDLINE database for articles in English concerning hairy cell leukemia, skin lesions, leukemia cutis, adverse events, infectious, cutaneous, drug reactions, neutrophilic dermatoses, secondary neoplasms, and vasculitis was conducted via PubMed. Publications from January 1980 to September 2020 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles.

Leukocytoclastic vasculitis associated with hairy cell leukemia at diagnosis: a case report and review of the literature

BACKGROUND

Autoimmune manifestations may occur in patients with hairy cell leukemia (HCL), and some rare cases of polyarteritis nodosa and leukocytoclastic vasculitis have been reported. However, data regarding the treatment of these cutaneous manifestations are lacking, given the rarity of the concomitance of HCL and vasculitic syndromes.

CASE PRESENTATION

We present a 37-year-old man with paraneoplastic leukocytoclastic vasculitis complicating newly diagnosed HCL. The vasculitis completely resolved after the first 3 weekly administrations of cladribine, which is regarded as the gold-standard treatment for this disease. The underlying leukemia showed refractoriness to the same agent, thus requiring a second line of treatment.

CONCLUSIONS

The clinical picture we have observed is of interest for the following reasons: i) it confirms an existing pathogenetic relationship between this lymphoproliferative disorder and its cutaneous manifestations, as suggested by the prompt resolution of the purpuric lesions upon cladribine administration; ii) it indicates that cladribine is an effective treatment for HCL-related paraneoplastic syndromes, including leukocytoclastic vasculitis; iii) the evolution and the outcomes of the paraneoplastic manifestations may be independent of those of the underlying leukemia, which showed less than a partial response to its initial treatment.