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 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.

[Macular lymphocytic arteritis and periarteritis nodosa: A case report showing diagnostic and nosological challenges posed by these two entities]

BACKGROUND

Macular lymphocytic arteritis is a recently described type of cutaneous vasculitis involving vessels of medium size. Authors consider it as a form of polyarteritis nodosa. Herein we report a case of macular lymphocytic arteritis during the course of which periarteritis nodosa appeared.

PATIENTS AND METHODS

A 50-year-old man, with no history other than chronic venous insufficiency of the lower limbs, presented with an asymptomatic eruption involving all four limbs, mainly the lower limbs, and appearing in episodes. Physical examination revealed brown macules, in some cases outlining the configuration of livedo reticularis. Laboratory findings were normal except for the presence of low levels of anticardiolipin activity at diagnosis, which had subsided three months later. Histological examination of the skin biopsy showed lymphocytic arteritis with some histiocytes and neutrophils, as well as an eosinophilic ring of parietal necrosis. Six months later, the patient developed multineuritis, leading to the diagnosis of polyarteritis nodosa. A diagnosis of cutaneous polyarteritis nodosa could also have been made based on the association of cutaneous livedo and locoregional polyneuritis without systemic involvement.

DISCUSSION

The diagnosis of macular lymphocytic arteritis is based upon clinical and histological findings and upon disease progression. This entity seems to belong to the same spectrum as periarteritis nodosa, especially in the cutaneous form. Given the lack of knowledge concerning progression from macular lymphocytic arteritis to nodosa periarteritis, close patient monitoring is called for, as illustrated by our case report.

Macular arteritis associated with concurrent HIV and hepatitis B infections: a case report and evidence for a disease spectrum association with cutaneous polyarteritis nodosa

We report the first case of macular arteritis in a 33-year-old Black, African female with concurrent human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infections. Of particular interest in macular arteritis is the striking discordance between the clinical presentation and the histopathological findings, a fact that both dermatologists and dermatopathologists should be aware. Histopathologically, the case showed typical findings of macular arteritis with a perivascular, predominantly lymphocytic, infiltrate and intraluminal thrombosis. Both HIV and HBV have been reported as viral inducers of cutaneous polyarteritis nodosa (PAN). Their association with macular arteritis in this case supports existing evidence that macular arteritis and cutaneous PAN represent a single-disease spectrum of vasculitides, with macular arteritis representing the chronic, lymphocytic and indolent stage, and cutaneous PAN the neutrophilic, acute stage with a risk for systemic progression. Lymphocytic thrombophilic arteritis (LTA), a third, uncommon disease would be in between macular arteritis and cutaneous PAN on a spectrum. Features of this case and other published cases provide strong evidence that there is a single, mild-to-severe disease spectrum of macular arteritis-LTA-cutaneous PAN.