Sir, A 32-year-old woman presented to us with multiple painful nodules and erythema on her ankles which had appeared two weeks previously. She had a mild fever for previous half a year and experienced blurred vision and conjunctival hyperemia for a month, which was diagnosed as iridocyclitis. On physical examination, her ankles were swollen and tender, and irregularly-shaped erythema with unclear borders was observed (<xref ref-type="fig" rid="F1">Fig. 1</xref>). Laboratory findings revealed leukocytosis in her peripheral blood and a slightly increased C-reactive protein level (5.3 mg/dl). Myeloperoxidase-anti-neutrophil cytoplasmic antibody (MPO-ANCA), proteinase-3 (PR3)–ANCA, and antiphospholipid antibody were all negative. Histological examination of the erythema revealed a thrombus of a subcutaneous vessel (<xref ref-type="fig" rid="F2">Fig. 2</xref>) along with dense infiltration of neutrophils, lymphocytes and their nuclear dust in the vessel wall and deposition of fibrin on the wall as well as diapedesis of red blood cells (<xref ref-type="fig" rid="F3">Fig. 3</xref>). Both Elastica-Masson and Elastica–van Gieson staining showed signs of non-circumferential single-layered elastic fibers along the inner cavity of the vessel and intravascular lumen being compressed (<xref ref-type="fig" rid="F4">Fig. 4</xref>). Later, we interviewed her in detail and found that she often got aphthous stomatitis. We made a conclusive diagnosis of incomplete-type Behçet’s disease. <fig id="F1"> <label>Figure 1</label> <caption> Irregularly shaped erythema with unclear borders on the ankles. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g001.tif"/> </fig> <fig id="F2"> <label>Figure 2</label> <caption> A thrombus of a subcutaneous vessel. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g002.tif"/> </fig> <fig id="F3"> <label>Figure 3</label> <caption> Infiltration of neutrophils, lymphocytes and their nuclear dust in the vessel wall with deposition of fibrin on the wall as well as diapedesis of red blood cells. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g003.tif"/> </fig> <fig id="F4"> <label>Figure 4</label> <caption> Non-circumferential single-layered elastic fibers along the inner cavity of the vessel and compressed intravascular lumen was revealed by Elastica-Masson and Elastica–van Gieson staining. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g004.tif"/> </fig> Prior to the study, patient gave written consent to the examination and biopsy after having been informed about the procedure. Our case presented with multiple painful nodules on the bilateral lower limbs. At first, we clinically diagnosed her as having cutaneous polyarteritis nodosa (cPN), and histological features were suggestive of vasculitis. However, detailed examination revealed a thrombus with severe perivascular infiltration of inflammatory cells in the subcutis, and Elastica–van Gieson staining detected concentric bundles of elastic fibers between smooth muscles in veins. Prior to the onset of the cutaneous lesions, the patient had been diagnosed as having iridocyclitis. Thrombophlebitis was observed as the sole cutaneous sign, unaccompanied by aphthae, erythema nodosum, or folliculitis. Thus, we diagnosed our patient as having incomplete-type Behçet’s disease. Thrombophlebitis sometimes mimics cPN not only clinically but also histologically and is therefore easily misdiagnosed as cPN [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>]. Chen [<xref ref-type="bibr" rid="ref3">3</xref>] reported the main reasons for misdiagnosis, i.e. i) subcutaneous veins in the lower legs have a thick muscular layer that resembles that of the muscular veins, ii) tissue sections obtained vertically show a concentric muscular layer with a round luminal appearance, which resembles an internal elastic lamina in the muscular layer of the arteries, and iii) subcutaneous veins in the lower legs reveal intimal elastic fiber proliferation, resembling that of the arteries. Although the differential diagnosis is sometimes difficult, thrombophlebitis should be considered when diagnosing cPN in order to avoid misdiagnosis and overtreatment. </sec> <sec id="sec1-2"> <title>CONSENT

OURD

Our Dermatol Online

2081-9390

Our Dermatology Online

Poland

OURD-6-367

10.7241/ourd.20153.100

Letter to the Editor

Superficial thrombophlebitis mimicking cutaneous polyarteritis nodosa as an early and sole cutaneous manifestation of Behçet’s disease

Hiraiwa

Tomoko

Yamamoto

Toshiyuki

Department of Dermatology, Fukushima Medical University, Fukushima 960-1295, Japan

Corresponding author: Dr. Tomoko Hiraiwa, E-mail: toishi@fmu.ac.jp

2015

6 3 367 368 24122014 10062015

2015

This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Sir, A 32-year-old woman presented to us with multiple painful nodules and erythema on her ankles which had appeared two weeks previously. She had a mild fever for previous half a year and experienced blurred vision and conjunctival hyperemia for a month, which was diagnosed as iridocyclitis. On physical examination, her ankles were swollen and tender, and irregularly-shaped erythema with unclear borders was observed (<xref ref-type="fig" rid="F1">Fig. 1</xref>). Laboratory findings revealed leukocytosis in her peripheral blood and a slightly increased C-reactive protein level (5.3 mg/dl). Myeloperoxidase-anti-neutrophil cytoplasmic antibody (MPO-ANCA), proteinase-3 (PR3)–ANCA, and antiphospholipid antibody were all negative. Histological examination of the erythema revealed a thrombus of a subcutaneous vessel (<xref ref-type="fig" rid="F2">Fig. 2</xref>) along with dense infiltration of neutrophils, lymphocytes and their nuclear dust in the vessel wall and deposition of fibrin on the wall as well as diapedesis of red blood cells (<xref ref-type="fig" rid="F3">Fig. 3</xref>). Both Elastica-Masson and Elastica–van Gieson staining showed signs of non-circumferential single-layered elastic fibers along the inner cavity of the vessel and intravascular lumen being compressed (<xref ref-type="fig" rid="F4">Fig. 4</xref>). Later, we interviewed her in detail and found that she often got aphthous stomatitis. We made a conclusive diagnosis of incomplete-type Behçet’s disease. <fig id="F1"> <label>Figure 1</label> <caption> Irregularly shaped erythema with unclear borders on the ankles. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g001.tif"/> </fig> <fig id="F2"> <label>Figure 2</label> <caption> A thrombus of a subcutaneous vessel. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g002.tif"/> </fig> <fig id="F3"> <label>Figure 3</label> <caption> Infiltration of neutrophils, lymphocytes and their nuclear dust in the vessel wall with deposition of fibrin on the wall as well as diapedesis of red blood cells. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g003.tif"/> </fig> <fig id="F4"> <label>Figure 4</label> <caption> Non-circumferential single-layered elastic fibers along the inner cavity of the vessel and compressed intravascular lumen was revealed by Elastica-Masson and Elastica–van Gieson staining. </caption> <graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="OURD-6-367-g004.tif"/> </fig> Prior to the study, patient gave written consent to the examination and biopsy after having been informed about the procedure. Our case presented with multiple painful nodules on the bilateral lower limbs. At first, we clinically diagnosed her as having cutaneous polyarteritis nodosa (cPN), and histological features were suggestive of vasculitis. However, detailed examination revealed a thrombus with severe perivascular infiltration of inflammatory cells in the subcutis, and Elastica–van Gieson staining detected concentric bundles of elastic fibers between smooth muscles in veins. Prior to the onset of the cutaneous lesions, the patient had been diagnosed as having iridocyclitis. Thrombophlebitis was observed as the sole cutaneous sign, unaccompanied by aphthae, erythema nodosum, or folliculitis. Thus, we diagnosed our patient as having incomplete-type Behçet’s disease. Thrombophlebitis sometimes mimics cPN not only clinically but also histologically and is therefore easily misdiagnosed as cPN [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>]. Chen [<xref ref-type="bibr" rid="ref3">3</xref>] reported the main reasons for misdiagnosis, i.e. i) subcutaneous veins in the lower legs have a thick muscular layer that resembles that of the muscular veins, ii) tissue sections obtained vertically show a concentric muscular layer with a round luminal appearance, which resembles an internal elastic lamina in the muscular layer of the arteries, and iii) subcutaneous veins in the lower legs reveal intimal elastic fiber proliferation, resembling that of the arteries. Although the differential diagnosis is sometimes difficult, thrombophlebitis should be considered when diagnosing cPN in order to avoid misdiagnosis and overtreatment. </sec> <sec id="sec1-2"> <title>CONSENT

The examination of the patient was conducted according to the Declaration of Helsinki principles.

REFERENCES 1

Vikas

Atul

Singh

Sarbmeet

Mohan

Behçet disease with relapsing cutaneous polyarteritis nodosa-like lesions, responsive to oral cyclosporine therapy

Dermatol Online J 2003 9 9

Heller

Behçet disease (incomplete) and cutaneous polyarteritis nodosa

Dermatol Online J 2005 11 25

Chen

The misdiagnosis of superficial thrombophlebitis as cutaneous polyarteritis nodosa: features of the internal elastic lamina and the compact concentric muscular layer as diagnostic pitfalls

Am J Dermatopathol 2010 32 688 93

Source of Support: Nil,

Conflict of Interest: None declared.