Infliximab as disease-modifying therapy

Infliximab for the treatment of disseminated pyoderma gangrenosum associated with ulcerative colitis. Case report and literature review

We report the case of a 19-year-old woman who developed an acute disseminated pyoderma gangrenosum (PG) during a severe flare of ulcerative colitis (UC). She was successfully treated with a 3-dose regimen of the anti-tumor-necrosis-factor-alpha antibody infliximab. The literature on the effectiveness of this biological agent was reviewed, including 8 other cases of UC-associated PG and 77 cases of Crohn's-disease-associated PG. This case report and the review of the literature demonstrate that infliximab can be successfully used to treat patients with PG associated with inflammatory bowel diseases.

Stridor in Crohn disease and the use of infliximab

Extraintestinal manifestations of Crohn disease are well recognized. Upper airway obstruction is a very rare but important complication that usually responds to high-dose steroids. We report a case of Crohn disease initially presenting with respiratory symptoms and subsequently resulting in acute severe upper airway obstruction, which failed to respond to steroids but dramatically responded to the first documented use of infliximab in this context.

TNF-alpha blockade down-regulates the CD40/CD40L pathway in the mucosal microcirculation: a novel anti-inflammatory mechanism of infliximab in Crohn's disease

The CD40/CD40 ligand (CD40L) pathway is involved in Crohn's disease (CD) pathogenesis. In the patients' circulation, soluble CD40L (sCD40L) levels are elevated and surface CD40L is increased in platelets and T cells, whereas in the intestine CD40 is overexpressed in the microvasculature and CD40L in platelets and T cells. The therapeutic effects of infliximab in CD are attributed to its systemic anti-TNF-alpha action, but because TNF-alpha modulates both CD40 and CD40L, we investigated whether infliximab affects the CD40/CD40L pathway in the intestine. Eighteen CD patients were evaluated before and after infliximab therapy. Plasma sCD40L was measured by ELISA and platelet and peripheral blood T cell (PBT) CD40L expression by flow cytometry. Microvascular CD40 and VCAM-1 expression were assessed in mucosal biopsies by immunohistochemistry and by flow cytometry in human intestinal microvascular endothelial cells (HIMEC). Cell cultures were performed in the presence and absence of infliximab. Infliximab treatment significantly reduced plasma sCD40L levels and eliminated CD40 and VCAM-1 from mucosal microvessels. In vitro infliximab prevented TNF-alpha-induced CD40 and VCAM-1 expression by HIMEC, and reduced PBT, but not platelet, surface CD40L expression and sCD40L release. In addition, infliximab decreased T cell-induced VCAM-1 expression in HIMEC by down-regulating CD40L in T cells and promoting T cells apoptosis. These findings point to a novel mechanism of action of infliximab, i.e., the disruption of CD40/CD40L-dependent cognate interactions between intestinal microvessels and T cells. Thus, in addition to neutralizing TNF-alpha and inducing T cell death, the therapeutic effects of infliximab in CD appear to be also mediated by inhibition of vascular inflammation in the gut.

T-cell Lymphopenia Associated with Infliximab and Cyclophosphamide

We report the first case of T-cell lymphopenia in a woman with rheumatoid arthritis who developed molluscum contagiosum with infliximab and cyclophosphamide. She presented in July 2000 with optic neuropathy and arthritis refractory to nonsteroidal anti-inflammatory drugs. After starting prednisone and cyclophosphamide, she became leukopenic (1.8x10 cells/microL), a condition that resolved with decreasing of the cyclophosphamide dose. In June 2002, the patient continued to have synovitis despite treatment with prednisone, cyclophosphamide, gabapentin, and celecoxib; blood counts were normal and infliximab was started. Her symptoms improved, but leukocyte counts declined (nadir of 1.5x10 cells/microL) despite discontinuing cyclophosphamide. She developed molluscum contagiosum after 8 months on infliximab (CD4 count, 492; HIV enzyme-linked immunosorbent assay and Western blot negative). Her symptoms flared after 10 months on infliximab; after the dose of infliximab was increased, her CD4 count fell to 114. Infliximab was discontinued and her leukocyte and CD4 count increased. This is the first reported case of leukopenia and T-cell suppression associated with infliximab and cyclophosphamide.