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Vasculitis
NicolasKluger
29
29.1 Diagnosis ofCutaneous
Vasculitis Is Made
onHistology
Physical cutaneous signs of vasculitis are wide
and nonspecic. Cutaneous vasculitis (CV)
affects the skin with varying intensity, depth, and
distribution. Even though a certain number of
syndromes have been described, a patient may
present with symptoms that overlap with another
clinical diagnosis making a diagnosis “at rst
sight” impossible. Most of all, vasculitis has a
histopathologic denition; therefore, its conrmation comes only from the microscopic examination of the lesion [1–5].
The diagnosis of CV is made by microscopic
examination of hematoxylin-eosin-stained biopsies. A list of criteria allows a trained pathologist
to diagnose and distinguish an active vasculitis
from chronic and healed lesions of vasculitis and
changes that are adjacent to vasculitis and may
help to dene a subtype or the etiology of the
CV. Inammatory inltrates within and around
the vessel walls associated with intramural and/
or intraluminal brin deposition (brinoid necrosis) conrm the diagnosis of vasculitis. Some
changes are suggestive of active vasculitis such
as red blood cell extravasation, perivascular
N. Kluger (*)
Departments of Dermatology, Allergology and
Venereology, Helsinki University Hospital and
University of Helsinki, Helsinki, Finland
e-mail: nicolas.kluger@hus.
nuclear dust (leukocytoclasia), eccrine gland
necrosis, ulceration, and necrosis/infarction. In
the absence of brinoid necrosis, the diagnosis of
CV becomes more difcult. Lamination of the
adventitia, media, and/or intima; perivascular
nuclear dust (leukocytoclasia) without brinoid
necrosis; loss of the elastic lamina with acellular
scar tissue; or subendothelial intramuscular and/
or adventitial inammatory cells in large vessels
are all other indications for vessel wall damages
[1–5].
A direct immunouorescence (DIF) examination is also recommended in case of CV.It does
not conrm the diagnosis of CV but allows to orient for one or another diagnosis.
• Absence of immune complex is in favor for
pauci-immune vasculitis: granulomatosis with
polyangiitis (Wegener’s, GPA), eosinophilic
granulomatosis with polyangiitis (Churg-
Strauss syndrome, EGPA), and microscopic
polyangiitis (MPA).
• Immunoglobulin (Ig) G, IgM, IgA, and/or
C3in or around the vessels may be found in
immune-mediated vasculitis like
cryoglobulinemia.
• In all cases of CV, immune depositions of Ig
and complement may be found, especially C3
and IgM.
© The Author(s) 2024
L. Téot et al. (eds.), Skin Necrosis, https://doi.org/10.1007/978-3-031-60954-1_29
205
206
N. Kluger
However, the older the biopsied lesion is, the
less immunoglobulin is found. After 72 h, only
C3 is detected. Therefore, a negative DIF does
not rule out the diagnosis of CV [1–5].
• Predominance of IgA is highly in favor for
IgA vasculitis (Henoch-Schönlein purpura)
without being constant or specic.
• IgM depositions are observed, especially in
case of circulating rheumatoid factor or cryo-
globulinemia. IgA deposits are absent in case
of cryoglobulinemia.
Of note, positive DIF without pathological
assessment of CV is not relevant.
After conrmation of the diagnosis of CV
itself, vasculitis may be dened more accurately
by vessel size involvement (small, small and
medium, and medium to large vessel), extent of
the lesions (supercial perivascular to dermal
and/or subcutaneous), and predominant inammatory cell inltration. The nding of smallvessel vasculitis with predominance of
neutrophilic inltrate and positive DIF is indicative of cutaneous leukocytoclastic vasculitis, IgA
vasculitis, urticarial vasculitis, or erythema elevatum diutinum. More rarely, other cells may
predominate such as eosinophils or lymphocytes.
Presence of both small- and medium-sized vas-
culitis favors ANCA-associated/pauci-immune
vasculitis (with negative DIF): EGPA, MPA,
GPA or cryoglobulinemia, connective tissue disease (lupus, rheumatoid arthritis, etc.), or hypocomplementemic vasculitis if DIF is positive.
Polyarteritis nodosa is characterized by a neutrophilic inltration associated with a mediumvessel artery vasculitis [1–5].
It is considered that biopsy of CV is not of
help to determine its cause [6]. Tissue eosinophilia could point out towards drug-induced vasculitis [7]. Some extravascular histologic pattern
found in the surrounding tissue may be helpful to
indicate a specic disease. Thus, palisading granulomatous dermatitis (“Winkelmann granuloma”) is in favor for GPA, EGPA, rheumatoid
arthritis, or systemic lupus erythematosus.
Presence of eosinophils and ame gures associated with such granulomas is found in EGAP
while neutrophils and basophilic debris in PGA
and rheumatoid vasculitis. Vacuolar interface
dermatitis with sometimes dermal mucin deposition is associated with lupus erythematosus and
dermatomyositis. Intraepidermal or dermal pustules with neutrophil small-vessel vasculitis are
related to an infectious related vasculitis. Skin
biopsy allows excluding pseudovasculitic disorder, a wide group of heterogeneous diseases that
may mimic cutaneous vasculitis [8] (Table29.1).
29 Vasculitis
207
Table 29.1 Approach to the diagnosis of cutaneous vasculitis and its differential diagnosis [1, 6]
208
N. Kluger
29.2 Pitfalls
In order to enable the diagnosis of vasculitis, the
choice of the “best” lesion is crucial [1–5]. A
lesion of cutaneous vasculitis should be analyzed
within the rst 48h after its appearance; otherwise, typical signs of vasculitis may be absent. A
fresh purpuric lesion displays within the rst
24-h brin deposits in the vessel wall, neutrophilic inltration, surrounding hemorrhage, and
intranuclear debris.
After 24 h, lymphocytes and macrophages
replace neutrophils.
After 48h, lymphocytes predominate.
Moreover, skin biopsy of an inltrated lesion
must include the epidermis, dermis, and hypodermis to determine the size of the affected vessels.
Some CV affects typically the upper part of the
dermis like IgA vasculitis. Therefore, a punch
skin biopsy will permit to show the lesions. In the
case of polyarteritis nodosa, deep muscular vessels of the dermis-hypodermis and the hypodermis are affected, which implies a deep incisional
biopsy. Similarly, a livedo should be biopsied on
its most inltrated or necrotic areas with similar
deep biopsy [9].
In some specic cases, an incidental vasculitis
may be found on the skin biopsy. This pathologic
statement should not mislead to diagnose a
vasculitis:
• Biopsy performed on an ulcer.
• Biopsy in lesions related to neutrophilic der-
matoses (Sweet’s syndrome).
29.3 Clinical Pathologic
Correlation
The cutaneous lesions correlate sometimes with
the size of the affected vessels [1–5].
• Palpable purpura, inltrated erythema, urti-
caria, vesicles, and blisters are mainly related
to small-vessel vasculitis of the dermis.
• Subcutaneous nodules, ulceration, and gan-
grene are frequently related to medium-sized
vessel vasculitis located at the dermohypodermal junction or in the subcutaneous
fat.
• Necrosis and livedo occur when either small
or larger vessels are involved.
29.4 Clinical Manifestations
Cutaneous vasculitis displays a wide range of
elementary lesions that may be associated with
and lead to a pleomorphic appearance of the
eruption [1–5]. CV may manifest variously as:
• Atypical urticaria, with distinctive feature
from common urticaria: duration of the lesions
longer than 24h, presence of purpura, postinammatory pigmentation or ecchymoses, and
symptoms of burning rather than itching.
• Palpable purpura: the most frequent manifes-
tation but nonspecic; asymptomatic or burning; localized on the lower limbs, ranging
from tiny red macules and pinhead to coinsized petechia, but also sometimes to more
extensive plaques and ecchymoses; may disclose a necrotic evolution leading to vesicles,
blisters, erosions, ulcerations, and ulcer. It is
often an association of different lesions in a
same patient simultaneously: erythematous to
purpuric macules, papules, and necrotic
lesions.
• Retiform purpura is a peculiar clinical form of
branching purpuric lesions in a shnet pattern
for which a distinction from an inltrated or
necrotic livedo is difcult. Retiform purpura
implies the performance of a skin biopsy like
any inltrated purpura or livedo.
• Other manifestations: inltrated erythema;
hemorrhagic vesicles; ulcers; inammatory,
tender, or painful dermal or hypodermal nodules; livedo racemosa, infarcts, and digital
gangrene. Lesions affect primarily the lower
limbs. Upper extremity, trunk, and head and
neck involvement are not usual and may be
considered as a sign of severity and/or of a
systemic vasculitis (Figs.29.1, 29.2, 29.3, and
29.4).
29 Vasculitis
209
Fig. 29.4 Extensive necrotizing vasculitis of the leg
Fig. 29.1 Vasculitis of the lower limbs associated with
different clinical lesions of purpura: macules, papules,
and vesiculous lesions. Notice the absence of lesions on
the dorsum of the feet due to the compression of the shoes
Fig. 29.2 Necrotic lesions of the lower legs during cutaneous vasculitis
Fig. 29.3 Cryoglobulinemic vasculitis with purpura and
leg ulcer
Other skin manifestations are associated with
systemic vasculitis, but they do not display vasculitis upon histology [1]:
• Extravascular necrotizing granuloma: occurs
during Churg-Strauss syndrome especially,
red to purple papules or nodules involving
symmetrically the extensor aspects of the
elbows and the ngers, but other localizations
have also been reported.
• Panniculitis: recurrent crops of erythematous,
edematous, and tender subcutaneous nodules;
usually of symmetrical distribution on the
thighs and the lower legs; spontaneous regression with hypopigmentation and atrophic scar
due to fat necrosis (lobular panniculitis) or the
extensor aspects of the lower limbs with a
spontaneous regression without atrophic scar
(septal panniculitis).
• Pyoderma gangrenosum.
• Granuloma: granulomatous lesions with neither vasculitis nor central necrosis may be
observed in systemic vasculitis, especially
WG with a highly variable presentation ranging from papules, nodules, subcutaneous
inltration, and pseudotumor to chronic ulcers
and affecting any site of the body.
• Supercial thrombophlebitis.
• Gangrene: resulting from arterial occlusion
and may be observed in all vasculitis involving medium- or large-sized arteries.
• Raynaud’s phenomenon: classically associated with all types of vasculitis. However, its
prevalence is unknown in many vasculitis, and
its diagnostic value is very low.
210
N. Kluger
29.5 Classication
Classication of vasculitis is a real brainteaser
[1]. Existence of overlapping clinical features,
lack of knowledge regarding precise etiopathogenetic process of each vasculitis, and lack of
“pathognomonic” clinical, laboratory, or radiologic ndings make it almost impossible to have
a perfect classication. Several classications
have been proposed, each of them presenting
advantages and weaknesses. Most commonly
used criteria for classication of vasculitis are of
the American College of Rheumatology (ACR)
established in 1990 [10] and the Chapel Hill
Consensus Conference (CHCC) that was revised
in 2012 [11]. The latter is a nomenclature system
of vasculitis providing names and denitions
(Table29.2). Of note, a dermatologic addendum
was published to standardize the name and denitions for cutaneous vasculitis [12]. Classication
criteria should be restricted to their primary use,
i.e., stratify uniform populations who carry a
Table 29.2 Names and denitions for vasculitides
adopted by the 2012 International Chapel Hill Consensus
Conference on the Nomenclature of Vasculitides [11]
Large-vessel vasculitis (LVV)
Vasculitis affecting the aorta and its major branches
more often than other vasculitides
Takayasu arteritis (TAK)
Giant cell arteritis (GCA)
Medium-vessel vasculitis (MVV)
Vasculitis that predominantly affects medium arteries
dened as the main visceral arteries and their branches
Polyarteritis nodosa (PAN)
Kawasaki disease (KD)
Small-vessel vasculitis (SVV)
Antineutrophil cytoplasmic antibody (ANCA)associated vasculitis (AAV)
Microscopic polyangiitis (MPA)
Granulomatosis with polyangiitis (Wegener’s)
(GPA)
Eosinophilic granulomatosis with polyangiitis
(Churg-Strauss) (EGPA)
Immune complex SVV
Anti-glomerular basement membrane (anti-GBM)
disease
Cryoglobulinemic vasculitis (CV)
IgA vasculitis (Henoch-Schönlein) (IgAV)
Hypocomplementemic urticarial vasculitis (HUV)
(anti-C1q vasculitis)
(continued)
Table 29.2 (continued)
Variable vessel vasculitis (VVV)
Vasculitis with no predominant type of vessel involved.
Can affect vessels of any type and size
Behcet’s disease (BD)
Cogan’s syndrome (CS)
Single-organ vasculitis (SOV)
Vasculitis in a single organ that has no features
indicating that it is a limited expression of a systemic
vasculitis
Cutaneous leukocytoclastic angiitis
Cutaneous arteritis
Primary central nervous system vasculitis isolated
aortitis
Others
Vasculitis associated with systemic disease
Lupus vasculitis
Rheumatoid vasculitis
Sarcoid vasculitis
Others
Vasculitis associated with probable etiology
Hepatitis C virus-associated cryoglobulinemic
vasculitis
Hepatitis B virus-associated vasculitis
Syphilis-associated aortitis
Drug-associated immune complex vasculitis
Drug-associated ANCA-associated vasculitis
Cancer-associated vasculitis
Others
diagnosis. In clinical practice, a nal diagnosis
should rely on the interpretation of clinical, laboratory, radiologic, and pathological ndings.
29.6 Approach totheDiagnosis
ofCutaneous Vasculitis
• The rst step being completed—having
proved by a skin biopsy the presence of cutaneous vasculitis and analyzed its precise subtype (cell inltration, size of the involved
vessel, DIF)—the physician collects all the
relevant data that will help him (1) to establish
the severity of the CV by the absence or presence of systemic involvement that will prompt
to initiate immunosuppressive treatment and
(2) to identify a potential curable cause [1]
(Table29.3).
• The precise diagnosis is made by the combi-
nation of clinical history and clinical, laboratory, and radiologic ndings. Therefore,
patients’ precise past medical data, history
29 Vasculitis
211
Table 29.3 Approach to the diagnosis of isolated,
biopsy-proven, cutaneous vasculitis [1]
Establish the Severity : Systemic Involvement ?
Complete physical examination
General manifestations : fever, night sweats, weight
loss
Joint (arthralgias), muscles (myalgias), lung
(hemoptysis, cough, shortness of breath, wheezing),
heart (chest pain, murmur)
gastrointestinal tract (abdominal pain, gastro-intestinal
bleeding), ear, nose, throat (sinusitis, rhinitis) and
ocular symtoms
(scleritis, sicca syndrome), peripheral (paresthesia,
numbness) and central (cephalagia, seizures) nervous
system, urologic and
genital symptoms (hematuria, testicular pain)
Laboratory studies
Kidney function every 3 months : urinalysis,
proteinuria, blood urea/creatinine
Electrocardiography
Chest X-ray
Identify a Potential Cause
Recently introduced drug ?
Laboratory studies recommended in the absence of
clinical relevant symptoms
Blood cell count, C-reactive protein,
Serum electrophoresis
Liver tests: transaminases, hepatitis B and C virus
serologies
Cryoglobulins
Antinuclear antibodies, anti-dsDNA, anti-extractable
nuclear antigens (Ro/Ssa, La/SSb, RNP, Sm…),
rheumatoid factors
Antineutrophils cytoplasmic antibodies (ANCA)
Complement levels (CH50, C3, C4)
Anti-streptolysin O titers
Complementary exams according to medical history
and clinical ndings
HIV test
Blood culture
Lumbar puncture
Echocardiography
Viral serologies (parvovirus B19, Epstein Barr virus,
CMV, COVID-19…), proposed in case of clinical
suspicion, pregnancy or in immunocompromised
hosts
Sinus CT scan and teeth examination
of the disease including newly introduced
drugs, and episode evocative for acute infection are mandatory. Indeed, any cutaneous
vasculitis occurring in a patient with a
known systemic vasculitis should prompt to
look for the intercurrent triggering factor
like infection or a newly introduced drug
before diagnosis or are-up of the disease.
Physical examination must be complete and
extensive. Of note, peculiar attention should
be brought on relapsing retiform purpura in
young adults as it can disclose the abuse of
levamisole-adulterated cocaine. The patients
do present a striking involvement of the ear
that could be a clue to suspect such diagnosis [1].
• Physicians should not lose from sight and
warn the patients that in 50% of all cases of
cutaneous vasculitis, no specic cause is
found.
29.7 Management ofCutaneous
Vasculitis
Management of biopsy-proven CV includes the
following [1]:
• Looking for the presence of systemic involvement (heart, lung, kidney).
• Identifying a potential curable cause.
• However, complementary explorations should
be oriented by clinical context.
• Any patient with a known underlying disease
that may be responsible for CV should be
asked about any new drug intake and infectious like episode and carefully examined to
rule out another potential cause of vasculitis.
In most of the cases, CV remains restricted to
a single, self-limited, and short-lived episode of
purpura of the lower limbs without any visceral
involvement and any relapse. In this frequent situation, treatment is not compulsory. However,
support stockings or panty hose as well as bed
rest and leg elevation are recommended. Topical
corticosteroids or anti- inammatory agents can
be given for symptomatic relief [13]. Conversely,
there is to date no indication for heparin therapy
or antivitamin K treatment for the management
of vasculitis, except if additional thrombotic factors are found concomitantly (i.e. circulating
anti-phospholipids) (Table 29.4).
If the disease persists, worsens, or is symp-
tomatic (burning sensation, pain) with a restriction to the skin, various drugs can be given,
212
Table 29.4 Treatment of cutaneous vasculitis according to severity [13]
N. Kluger
Single,self-limited and short -
lived episode of purpuraof the
lower limbs without any
visceral involvement and any
relapse,
If the disease persists,worsen
or is symptomatic (burning
sensation, pain) with a
restrictionto the skin
Extensive, recurrent skin
diseasewith persistent lesions,
vesicles, ulcers, nodules;
intractable symptoms or
systemicvasculitis with other
organ involvement
•Treatment is notcompulsory
•Bed rest, elevatedlegs, support stockingsorpanty hose
•Topical corticosteroids, anti-inflammatory agents for
symptomaticrelief
•Colchicine (1mg/day)for onetothree months
• Dapsone(50-100 mg/day)
•Pentoxyphililine (400 mg, 3 timesaday).
•Combination
•Corticosteroids
•Methotrexate, azathioprine, cyclosporine, cyclophosphamide
•Intravenous immunoglobulins,rituximab
•TNF alpha antagonists (Behcet,…); tocilizumab (giant cell
arteritis)
usually colchicine at a dose of 1 mg/day for
1–3 months. Alternatives include dapsone
(50–100mg/day), alone or in combination with
colchicine [13], and pentoxifylline (400mg×3/
day), alone or in combination with other treatments [1–5]. Longer treatments can be given in
case of relapse after withdrawal.
Extensive, recurrent skin disease with persistent lesions, vesicles, ulcers, and nodules; intractable symptoms; or systemic vasculitis with other
organ involvement may prompt initiation of
immunosuppressive therapies such as
corticosteroids, methotrexate, azathioprine, mycophenolate mofetil, cyclosporine, or cyclophosphamide. Rituximab may be of interest in case of
severe vasculitis, in the ANCA-related group especially. The place of anti-tumor necrosis factor
remains to be established. Indeed, several cases of
severe cutaneous vasculitis have been treated successfully with iniximab. Besides, iniximab does
have a clear-cut indication for Behcet’s disease.
However, cases of vasculitis induced by iniximab
or other TNF alpha inhibitors, in patients with psoriasis especially, nuance the place of this class in
carefully selected cases.
Besides, management includes pain control
and standardized care for necrotic and brous
ulcers along with the control of the underlying
process [1].
References
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vasculitis: diagnosis and management. Clin Dermatol.
2006;24:414–29.
3. Carlson JA, Chen KR.Cutaneous vasculitis update:
small vessel neutrophilic vasculitis syndromes. Am J
Dermatopathol. 2006;28:486–506.
4. Crowson AN, Mihm MC Jr, Magro CM. Cutaneous
vasculitis: a review. J Cutan Pathol. 2003;30:161–73.
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5. Fiorentino DF. Cutaneous vasculitis. J Am Acad
Dermatol. 2003;48:311–40.
6. Jung AJ, Schaeffer M, Mitcov M, Scrivener Y, Cribier
B, Lipsker D.Clinicopathological study of purpura:
is a skin biopsy necessary for palpable purpura? Ann
Dermatol Venereol. 2016;143:347–53.
7. Bahrami S, Malone JC, Webb KG, Callen JP.Tissue
eosinophilia as an indicator of drug-induced cutaneous small-vessel vasculitis. Arch Dermatol.
2006;142:155–61.
8. Carlson JA, Chen KR. Cutaneous pseudovasculitis.
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American College of Rheumatology 1990 criteria for
the classication of vasculitis. Introduction. Arthritis
Rheum. 1990;33:1065–7.
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Necrobiosis Lipoidica
MirunaNegulescu
30
30.1 Introduction
Necrobiosis lipoidica (NL) is a rare chronic granulomatous skin disease usually associated with
diabetes mellitus, especially type 1 [1].
In 1930, Oppenheim rst described and called
it dermatitis atrophicans lipoidica diabetica [2]. It
was then named necrobiosis lipoidica diabeticorum (NLD) by Urbach in 1932 [3]. The several
cases of NLD described in nondiabetic patients
led to deletion of “diabetes” word from the
denomination [2].
The relationship between NL and diabetes
mellitus is still debated. First, the link has been
established by studies from the 1960s, which
showed diabetes or abnormal glucose metabolism in over 60% of patients with NL [4]. Since
the 1960s, no prevalence-based studies on NL
have been conducted. Thereby, most studies
are based on the 65% incidence in their work
[4].
Despite the increased prevalence of NL in
diabetics, NL has also been met in patients
with normal glycemia, autoimmune thyroiditis, rheumatoid arthritis, sarcoidosis, inammatory bowel disease, and monoclonal
gammopathy [4].
30.2 Epidemiology
This pathology affects 0.3–1.2% of the diabetic
population with a female predominance (femaleto- male ratio 3:1) [1, 4]. The early symptoms
start typically in type 1 diabetic adults during the
third decade of life and the fourth decade in type
2 or nondiabetic people [4]. In up to 14% of
cases, diagnosis of diabetes is realized after NL
lesions, in up to 24% is simultaneously made,
and in 62% of cases occurs before NL lesions [4].
30.3 Pathogenesis andHistology
The pathogenesis of NL is still controversial. The
diabetic microangiopathy has been involved [1,
4, 5]. An initial immune complex-mediated vas-
culitis is suggested by the presence of immunoglobulin M deposits, C3, and brin in the vessel
walls in direct immunouorescence [1, 2].
Histologically, a collagen degeneration, granulomatous formation, fat deposition, and thickening of blood vessel walls are described [2, 4, 5].
30.4 Clinical Findings
andComplications
Initial alterations present as papules and nodules
M. Negulescu (*)
Department of Dermatology, Hôpital Erasme,
Université Libre de Bruxelles, Brussel, Belgium
e-mail: miruna.negulescu@ulb.ac.be
© The Author(s) 2024
L. Téot et al. (eds.), Skin Necrosis, https://doi.org/10.1007/978-3-031-60954-1_30
matching to form yellow-brown, nonpainful
patches, with active raised and erythematous borders (Figs.30.1 and 30.2). The center is atrophic,
215