Cutaneous lymphocytic thrombophilic (macular) arteritis

Macular arteritis (MA) has a striking discordance between the clinical presentation of hyperpigmented macules and the histopathologic findings of a lymphocytic arteritis with intraluminal hyalinized fibrin ring and thrombosis. It has been proposed that MA represents the chronic, indolent, lymphocytic form of the neutrophil-predominant cutaneous polyarteritis nodosa. MA usually affects middle-aged women asymptomatically on the legs. There is also a slightly more severe variant with more infiltrated plaques and livedo racemosa, termed lymphocytic thrombophilic arteritis. MA and lymphocytic thrombophilic arteritis have similar histologic features, both with a largely intact vascular elastic lamina, despite the abundant fibrin and endarteritis obliterans. There is no evidence for progression from MA to lymphocytic thrombophilic arteritis to cutaneous polyarteritis nodosa, and aggressive therapy should be avoided in MA, given the indolent, benign disease course.

Is macular lymphocytic arteritis limited to the skin? Long-term follow-up of seven patients

Background

Macular lymphocytic arteritis most commonly presents as hyperpigmented macules on the lower limbs. The pathogenesis of this disease is still unclear and there is an ongoing debate regarding whether it represents a new form of cutaneous vasculitis or an indolent form of cutaneous polyarteritis nodosa.

Objective

To describe clinical, histopathological, and laboratory findings of patients with the diagnosis of macular lymphocytic arteritis.

Methods

A retrospective search was conducted by reviewing cases followed at the Vasculitis Clinic of the Dermatology Department, School of Medicine, University of São Paulo, between 2005 and 2017. Seven patients were included.

Results

All cases were female, aged 9–46 years, and had hyperpigmented macules mainly on the legs. Three patients reported symptoms. Skin biopsies evidencing a predominantly lymphocytic infiltrate affecting arterioles at the dermal subcutaneous junction were found, as well as a typical luminal fibrin ring. None of the patients developed necrotic ulcers, neurological damage, or systemic manifestations. The follow-up ranged from 18 to 151 months, with a mean duration of 79 months.

Study limitations

This study is subject to a number of limitations: small sample of patients, besides having a retrospective and uncontrolled study design.

Conclusions

To the best of the authors’ knowledge, this series presents the longest duration of follow-up reported to date. During this period, none of the patients showed resolution of the lesions despite treatment, nor did any progress to systemic vasculitis. Similarities between clinical and skin biopsy findings support the hypothesis that macular lymphocytic arteritis is a benign, incomplete, and less aggressive form of cutaneous polyarteritis nodosa.

Lymphocytic Thrombophilic Arteritis: A Possible Association with Minocycline

We describe a case of lymphocytic thrombophilic arteritis in a 15-year-old girl who had previously taken minocycline for a year. Cutaneous polyarteritis nodosa and lymphocytic thrombophilic arteritis share many features and may both be triggered by minocycline. There may be a long latency between drug exposure to minocycline and development of disease.

Lymphocytic thrombophilic arteritis: A distinct inflammatory type I interferon and C5b-9 mediated subcutaneous endovasculitis

BACKGROUND

Lymphocytic thrombophilic arteritis is a recently recognized subcuticular larger vessel vasculitis characterized by striking vascular luminal thrombosis.

METHODS

The clinical features, histopathology and phenotypic profile of ten patients with lymphocytic thrombophilic arteritis were explored in an attempt to better define the entity from a clinical and pathophysiologic perspective.

RESULTS

The patients were all female (mean age of 43) presenting with generally asymptomatic lower and upper extremity hyperpigmented macules. A consistent picture diagnostic of a connective tissue disease syndrome was not seen. The disease was not progressive although it was typically persistent. The morphology was characterized by a temporally heterogeneous subcutaneous arteritis targeting the endothelium and intima with changes ranging from incipient intimal expansion by hyaluronic acid to concentric intimal fibrin deposition to one of an end stage acellular intraluminal obliterative fibrous arteriopathy. The infiltrate was predominated by lymphocytes and histiocytes. The intimal elastic lamina was intact in most cases. All tested cases showed intimal and endothelial C5b-9 deposition, an upregulated type I interferon microenvironment and marked upregulation of the inducible interferon gamma 16 protein.

CONCLUSIONS

Lymphocytic thrombophilic arteritis is a unique form of C5b-9 mediated arteritic endotheliopathy where the brunt of the changes involves the endothelium and intima and that is morphologically distinct from the transmural arteritis of benign cutaneous polyarteritis nodosa.