Angiography may appear normal, as was the case in our patient, even in the presence of biopsy or autopsy proven CNS vasculitis (selleck chemicals llc Alrawi et al. 1999). Alternatively, other conditions such as vasospasm or atherosclerosis (Duna and Calabrese 1995) may mimic vasculitis on a cerebral angiogram. In fact,
the estimated specificity of angiography Inhibitors,research,lifescience,medical for detecting vasculitis is between 14% and 60% (Chu et al. 1998; Kadkhodayan et al. 2004) and that of MRI is between 19% and 36% (Calabrese and Duna 1995; Duna and Calabrese 1995; Chu et al. 1998), while that of brain biopsy is between 87% and 100% (Duna and Calabrese 1995; Chu et al. 1998). An additional role for biopsy in these cases is to rule out alternative diagnoses, such as CNS lymphoma or infection, Inhibitors,research,lifescience,medical for which incorrect or delayed treatment could lead to poor outcome. The most commonly encountered risk associated with stereotactic brain biopsy is hemorrhage, the incidence of which ranges from 8 to 9%, with 1–4% of these hemorrhages being symptomatic (Field et al. 2001; McGirt et al. 2005). Overall mortality and morbidity have been estimated at 0.7% and 3.5%, respectively (Hall 1998). In each case, the risk of brain biopsy should be weighed against potential for incorrect diagnosis or continued/progressive neurologic disability. The etiology of this particular case of isolated CNS Inhibitors,research,lifescience,medical eosinophilic vasculitis
is unclear. The patient did not have peripheral eosinophilia as Inhibitors,research,lifescience,medical would be expected if the vasculitis were secondary to a hypersensitivity allergic reaction or parasitic infection and there were no parasites or amebae seen on brain biopsy. Hypereosinophilic syndrome (HES), defined as blood and/or tissue eosinophilia without underlying allergic, parasitic, or
Inhibitors,research,lifescience,medical other cause (Sheikh and Weller 2009) is a possible diagnosis. Neurologic manifestations in combination with systemic disease are common in HESs (~50%) (Sheikh and Weller, 2007). Churg-Strauss syndrome (CSS) is an HES associated with peripheral eosinophilic vasculitis that may also be associated with neurologic symptoms (~60%) (Sehgal et al. 1995). also However, diagnosis of CSS requires four of the following six diagnostic criteria: asthma, peripheral eosinophilia >10%, mono- or polyneuropathy, pulmonary infiltrates, paranasal sinus abnormality, and extravascular eosinophils (Masi et al. 1990). Our patient did not meet these criteria. Additionally, CSS is characterized by granulomatous eosinophilic vasculitis, and granulomata were absent in the biopsy specimen obtained from our patient. There have been case reports of “limited” CSS with eosinophilic vasculitis or extravascular granulomas in the absence of blood eosinophilia or asthma. These cases have included vasculitic involvement of the skin and eyes (Khan et al. 1996), lungs (Sevinc et al. 2004), kidneys (Sharma et al. 2004), and heart (Taira et al. 2005).