Page 46 - The Vasculitides, Volume 1: General Considerations and Systemic Vasculitis

22 David S. Younger

Henegar and colleagues [33] identified three positive predictive parameters including
HBV antigen and DNA in serum, arteriographic anomalies, and mononeuropathy or
polyneuropathy; and five negative predictive parameters including detection of ANCA;
asthma, ear, nose and throat signs; glomerulopathy; and cryoglobulinemia, that yielded
a70.6% sensitivity for control vasculitides and 92.3% specificity for all controls.

Small Vessel Vasculitides

ANCA-Associated Vasculitis

Microscopic Polyangiitis

Wohlwill [34], Davson and colleagues [35] and Wainwright and Davson [36] recognized
that fever, arthralgia, purpura, hemoptysis, pulmonary hemorrhage, abdominal pain, and
gastrointestinal bleeding preceded the explosive phase of systemic necrotizing vasculitis in
some patients with a disorder other than PAN that affected the kidney and lungs, with rapidly
progressive glomerulonephritis and pulmonary capillaritis. Such patients with selective
involvement of small microscopic arteries, arterioles, capillaries and venules including
glomerular and pulmonary alveolar capillaries were deemed to have microscopic PAN.
Among thirty-four such patients described by Savage and colleagues [37] the clinical
symptoms and signs at presentation were constitutional (67%), arthralgia (65%), purpura
(44%), hemoptysis in (32%), abdominal pain (32%), mouth ulcers (21%), sensory peripheral
neuropathy (18%), and CNS (headache, seizures) (18%). Eighty-five additional patients
studied by Guillevin and colleagues [38] with MPA so termed, had renal involvement (79%),
weight loss (73%), skin involvement (purpura, livedo, nodules, urticarial) (62%),
mononeuritis multiplex neuropathy (57%), fever (55%), arthralgia (50%), myalgia (48%),
vascular manifestations [hypertension, cardiac failure, pericarditis] 50%, lung involvement
(alveolar hemorrhage, pneumonitis, pleurisies) (24%), and CNS involvement (12%). Ahn and
colleagues [39] noted pANCA or anti-MPO antibody positivity in 69% of Korean MPA
patients, compared to 74.5% of positive ANCA in European patients, of whom 87% had a
pANCA staining pattern. Antibodies to PR3 were present in 8% of patients compared to MPO
in 61% of those as determined by ELISA. Childhood MPA (cMPA) appears to be very
uncommon and the criteria for diagnosis require three of the following features to be present:
abnormal urinalysis, granulomatous inflammation on tissue biopsy, nasal sinus inflammation;
subglottic, tracheal, or endobronchial stenosis; abnormal chest radiograph or chest CT scan,
and PR3 ANCA or cANCA staining [3]. Those with cMPA accounted for four of the first 32
children in the United States/Canadian ARChiVe registry [40].

Eosinophilic Granulomatosis with Polyangiitis

Contemporaneous with the description of MPA, the first patient with EGPA was
probably Case 1 of Lamb [41] reported in 1914 also under the heading of PAN. That patient,
a 26-year-old man with two years of worsening asthma, developed fever, palpable purpura,
nodular skin lesions, hemoptysis, vomiting, urinary difficulty and granular urinary casts. He
died one month later and postmortem examination showed necrotizing arteritis of small
arteries, with dense collections of extravascular eosinophils and tissue eosinophilia in the

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