The purpose of this study is to understand the safety and effectiveness of infliximab when used in clinical practice. This is a post-marketing surveillance study.

The investigator will record continuously from the first patient since the day of contract to the numbers of patients of contract based on Remicade approval.

Inclusion Criteria:

• Severe active Crohn's disease: the patients with severe active Crohn's disease who do not show any response to the treatment with corticosteroid or immunosuppressive agents, have no drug tolerance, or are contraindicated to such treatments.
• Fistula-type active Crohn's disease: the patients with fistula-type active Crohn's disease who do not show any response to general treatments such as antibiotics, drainage, or immunosuppressant.
• Ankylosing spondylitis: the patients with ankylosing spondylitis who do not show adequate response to general treatments, and with increased serological indices related to severe axial symptoms and inflammation.

Exclusion Criteria:

• None

The population of subjects will mainly be taken from the digestive or rheumatoid departments of internal medicine in university or general hospitals, where patients with Crohn's Disease and Ankylosing Spondylitis are generally treated. The period of surveillance is from 23 AUG 2005 to 22 AUG 2011.