Presence and interpretation of vascular immune deposits in human skin: the value of direct immunofluorescence

Diagnosis and management of leukocytoclastic vasculitis

Leukocytoclastic vasculitis (LCV) is a histopathologic description of a common form of small vessel vasculitis (SVV), that can be found in various types of vasculitis affecting the skin and internal organs. The leading clinical presentation of LCV is palpable purpura and the diagnosis relies on histopathological examination, in which the inflammatory infiltrate is composed of neutrophils with fibrinoid necrosis and disintegration of nuclei into fragments ("leukocytoclasia"). Several medications can cause LCV, as well as infections, or malignancy. Among systemic diseases, the most frequently associated with LCV are ANCA-associated vasculitides, connective tissue diseases, cryoglobulinemic vasculitis, IgA vasculitis (formerly known as Henoch-Schonlein purpura) and hypocomplementemic urticarial vasculitis (HUV). When LCV is suspected, an extensive workout is usually necessary to determine whether the process is skin-limited, or expression of a systemic vasculitis or disease. A comprehensive history and detailed physical examination must be performed; platelet count, renal function and urinalysis, serological tests for hepatitis B and C viruses, autoantibodies (anti-nuclear antibodies and anti-neutrophil cytoplasmic antibodies), complement fractions and IgA staining in biopsy specimens are part of the usual workout of LCV. The treatment is mainly focused on symptom management, based on rest (avoiding standing or walking), low dose corticosteroids, colchicine or different unproven therapies, if skin-limited. When a medication is the cause, the prognosis is favorable and the discontinuation of the culprit drug is usually resolutive. Conversely, when a systemic vasculitis is the cause of LCV, higher doses of corticosteroids or immunosuppressive agents are required, according to the severity of organ involvement and the underlying associated disease.

Nomenclature of Cutaneous Vasculitis: Dermatologic Addendum to the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides

OBJECTIVE

To prepare a dermatologic addendum to the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012) to address vasculitides affecting the skin (D-CHCC). The goal was to standardize the names and definitions for cutaneous vasculitis.

METHODS

A nominal group technique with a facilitator was used to reach consensus on the D-CHCC nomenclature, using multiple face-to-face meetings, e-mail discussions, and teleconferences.

RESULTS

Standardized names, definitions, and descriptions were adopted for cutaneous components of systemic vasculitides (e.g., cutaneous IgA vasculitis as a component of systemic IgA vasculitis), skin-limited variants of systemic vasculitides (e.g., skin-limited IgA vasculitis, drug-induced skin-limited antineutrophil cytoplasmic antibody-associated vasculitis), and cutaneous single-organ vasculitides that have no systemic counterparts (e.g., nodular vasculitis). Cutaneous vasculitides that were not included in the CHCC2012 nomenclature were introduced.

CONCLUSION

Standardized names and definitions are a prerequisite for developing validated classification and diagnostic criteria for cutaneous vasculitis. Accurate identification of specifically defined variants of systemic and skin-limited vasculitides requires knowledgeable integration of data from clinical, laboratory, and pathologic studies. This proposed nomenclature of vasculitides affecting the skin, the D-CHCC, provides a standard framework both for clinicians and for investigators.

Autoimmune keratolysis in a patient with leukocytoclastic vasculitis: unusual erythema elevatum diutinum with granulomatous pattern

PURPOSE

Leukocytoclastic vasculitis (LCCV) is an immune complex-mediated, small vessel disease that is clinically characterized by the presence of palpable purpuric lesions, most often in association with rheumatic diseases. Ocular manifestations of LCCV are rare.

METHODS

We describe a patient with an unusual granulomatous pattern of erythema elevatum diutinum (EED) associated with autoimmune keratolysis.

RESULTS

We studied a 64-year-old man with decreased visual acuity and nodular lesions in both hands. Ocular examination revealed bilateral superior corneal melting with perforation in the left eye and conjunctival thickening in both eyes, in association with a severe inflammatory reaction. Histopathologic examination of the conjunctiva revealed granulomatous vasculitis with neutrophilic infiltrate, giant cells, and fibroblastic proliferation. A punch biopsy taken from his skin showed similar characteristics that suggested EED; however, there were no giant cells.

CONCLUSION

To our knowledge, autoimmune keratolysis secondary to cutaneous LCCV (EED) has not been described previously, and there has been no description of granulomatous reaction (in the conjunctiva) in EED.

Erysipelas-like erythema of familial Mediterranean fever: clinicopathologic correlation

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive disease that tends to affect certain ethnic groups. It is characterized by recurrent, self-limited attacks of peritonitis, pleuritis, and synovitis. Erysipelas-like erythema (ELE) is the pathognomonic skin manifestation. Lesions are characterized by tender erythematous plaques, usually located on the lower legs. They may be triggered by physical effort and subside spontaneously within 48 to 72 hours of bed rest. Fever and leukocytosis may accompany this condition.

OBJECTIVE

The purpose of this study was to describe the histology and the immunofluorescence findings in ELE and to discuss these observations in relation to the clinical findings in FMF.

METHODS

We studied 7 patients with FMF in whom ELE developed. In all patients a biopsy was performed within 18 hours from onset of the lesion. In addition to routine hematoxylin and eosin stains, immunohistochemistry to evaluate the infiltrate and direct immunofluorescence were performed. Patients were followed up for their ELE lesions.

RESULTS

Histologic examination revealed edema of the superficial dermis and sparse perivascular infiltrate composed of a few lymphocytes, neutrophils, and nuclear dust. Vasculitis was not observed. Direct immunofluorescence showed, in all cases, deposits of C3 in the wall of the small vessels of the superficial vascular plexus. In some cases fibrinogen and IgM were also observed.

CONCLUSION

These findings are in accordance both with those found previously in the erysipelas-like phenomenon and those in the peritoneum of patients with FMF. The sparse infiltrate and the deposition of C3 also are compatible with the clinical picture of self-resolving lesions of short duration. It also suggests that erysipelas-like erythema belongs to the spectrum of neutrophilic dermatoses and supports a pathogenesis that involves abnormal inhibition of the inflammatory cascade.

Localization of hepatitis C virus in cutaneous vasculitic lesions in patients with type II cryoglobulinemia

OBJECTIVE

To investigate the role of hepatitis C virus (HCV) in the pathogenesis of the cutaneous vasculitis in patients with type II cryoglobulinemia.

METHODS

Using in situ hybridization detection of HCV, we studied 6 test patients and various control subjects. Serum HCV was quantitated, cryoglobulins were analyzed by column chromatography at 37 degrees C, and low-density lipoprotein (LDL) receptors on keratinocytes were detected using LDL labeled with fluorescent dye.

RESULTS

In the cutaneous vasculitic lesions from test patients, but not control subjects, the HCV virion was found in association with IgM and IgG. HCV alone was detected in some vessel walls, and in skin and ductal epithelium and vascular endothelium in inflamed, but not normal, skin. Cryoglobulins showed HCV, monomeric IgM, and monomeric IgG, with little or no immune complexes. The extent of the lesions correlated with levels of viremia. Up-regulation of LDL receptors on keratinocytes was detected in inflamed, but not normal, skin.

CONCLUSION

HCV was present in the cutaneous vasculitic lesions, most likely in complexes with IgM and IgG formed in situ. These findings and the correlation of the severity of the rash with the level of viremia suggest that HCV plays a major role in the pathogenesis of cutaneous vasculitis in these patients and strengthens the rationale for antiviral drug therapy. The presence of HCV in keratinocytes and ductal epithelial and vascular endothelial cells may be the in vivo manifestation of endocytosis of HCV by the LDL receptors that has recently been demonstrated in vitro. The up-regulation of LDL receptors on keratinocytes in inflamed skin is consistent with this postulation.