Background: Spontaneous cervical artery dissection (sCAD) is a nonatherosclerotic vascular disease of unknown etiology. Mild elevation of total plasma homocysteine (tHcy) levels may be a risk factor for sCAD, but the precise mechanism remains unknown. On the other hand, mild hyperhomocysteinemia is also associated with ischemic stroke related to atherothrombotic or small artery disease. We undertook a case-control study to compare the prevalence of mild hyperhomocysteinemia and tHcy levels between patients with a first ischemic stroke due to sCAD and healthy volunteers, as well as patients with a first ischemic stroke due to atherothrombotic or small artery disease. Methods: Fasting tHcy levels were determined in 346 consecutive patients with a first ischemic stroke due to sCAD (n = 86) and atherothrombotic or small artery disease (n = 260) within 24 h after the onset of symptoms, and in 100 healthy volunteers. Results: Mild hyperhomocysteinemia was more prevalent in patients with sCAD causing ischemic stroke (n = 33, 38%) than in healthy volunteers (n = 23, 23%; p = 0.034), and less prevalent than in patients with ischemic stroke due to atherothrombotic or small artery disease (n = 149, 57%; p = 0.001). Mean fasting tHcy levels of patients with ischemic stroke caused by sCAD showed a trend to be higher (11.4 ± 3.8 μmol/l) than those of healthy volunteers (10.2 ± 3.0 μmol/l, p = 0.61), but were lower than those of patients with stroke due to atherothrombotic or small artery disease (13.6 ± 6.6 μmol/l, p = 0.002). Conclusion: Our results suggest that mild hyperhomocysteinemia may be a risk factor for sCAD causing ischemic stroke, but further studies are needed to identify a possible mechanism. This study confirms the association of hyperhomocysteinemia with ischemic stroke due to atherothrombotic or small artery disease.

The carbohydrate antigen 19-9 (CA 19-9), a determinant (sialylated lacto-N-fucopentaose 119) of a circulating oligosaccharide antigen, is a frequently used tumor marker. Echinococcus spp. infects humans throughout the world and may be able to synthesize closely related molecules which could interfere with the measurement and interpretation of CA 19-9 concentration. The main objective of the present study was to determine the range of CA 19-9 levels in the sera of patients infected by E. granulosus (cystic hydatide disease; CYSHD) or E. multilocularis (alveolar hydatide disease; ALVHD). Serum samples were collected from patients (aged 10-85 years) over a period of 5 years: from 19 patients with CYSHD and from 20 patients with ALVHD. Infection was confirmed by positive Echinococcus serology and clinical evidence provided by imaging and/or histopathological findings. CA 19-9 was detectable in 13 patients with CYSHD (13.5 +/- 8.5 kU/l) and 13 patients with ALVHD (30.0 +/- 21 kU/l; p < 0.05). Thus ALVHD patients exhibited a significantly higher plasma level of CA 19-9 than CYSHD patients. The serum level of CA 19-9 assessed with an increased cut-off value (> 22 kU/l) was elevated in nine (45%) of 20 ALVHD patients compared to two (11%) of 19 CYSHD patients (p < 0.05). Sera from patients with Echinococcus multilocularis infection contain substances which cross-react with CA 19-9. These substances originate either from the parasite or are synthesized by the host in response to the infection, and possibly bear the Lewis-a antigen or closely related structures which are recognized by anti-CA 19-9 antibodies. Our findings are relevant to the investigation of patients presenting with cystic lesions for which the differential diagnosis includes an infectious or neoplastic origin.