Faculty Bibliography

OBJECTIVES: Infliximab, an anti-tumor necrosis factor (TNF) monoclonal antibody, might exert some of its long-term therapeutic effects in Crohn's disease (CD) by interacting directly with cells of the immune system such as monocytes and T lymphocytes via membrane TNF and by inducing apoptosis. Accordingly, the effects of inflix-imab on monocyte apoptosis and down-regulation of proinflammatory cytokines (reverse signaling) were assessed. METHODS: To assess apoptosis, monocytes from healthy individuals (controls) and CD patients were incubated in the presence or absence of infliximab or the apoptotic agent gliotoxin for 24 hours. Annexin V staining and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-FITC nick end labeling assay were used to measure early and late apoptosis. To measure the effects of infliximab on reverse signaling, monocytes from healthy individuals pretreated in vitro with infliximab were stimulated with lipopolysaccharide or staphylococcal enterotoxin A, and the induction of the proinflammatory cytokines, TNF-alpha, interleukin (IL)-1beta, IL-6, and IL-8 was measured by reverse transcription polymerase chain reaction. The effect of in vivo infliximab treatment of monocytes was similarly determined by comparing the responses of monocytes from CD patients before and immediately after infliximab infusion. RESULTS: Infliximab did not induce apoptosis of monocytes from either healthy individuals or CD patients but rather stabilized them. However, monocytes from healthy individuals treated with infliximab in vitro, or from CD patients infused with infliximab, produced significantly less TNF and other proinflammatory cytokines when stimulated with the bacterial products lipopolysaccharide and staphylococcal enterotoxin A. CONCLUSIONS: Apoptosis of monocytes is not responsible for the therapeutic effects of infliximab. However, some of the therapeutic effects of infliximab may be caused by its ability to down-regulate proinflammatory cytokines production by monocytes exposed to bacterial antigens

BACKGROUND: The tablet formulation of sodium phosphate (NaP) is a prescription osmotic purgative that has been marketed since 2001. The use of NaP tablets in patients with constipation has not been studied previously. OBJECTIVE: This study assessed the tolerability and efficacy of 28 days of therapy with NaP tablets (1.5 g NaP/tablet) in patients with chronic constipation. METHODS: Adults with functional constipation or constipation-predominant irritable bowel syndrome and Z-3 spontaneous bowel movements (BMs) during the 7-day screening/baseline period were eligible for this open-label, dose-ranging study. Patients were randomized to receive starting doses of 4 NaP tablets (group A) or 8 NaP tablets (group B) each morning for 28 days. After a minimum of 48 hours, the NaP dose could be titrated upward (in the case of no BM or no relief of symptoms) or downward (in the case of a predefined excess laxative response) by 2 tablets/d to a minimum of 2 tablets/d or a maximum of 12 tablets/d. Patients kept a diary of their BMs and gastrointestinal symptoms. A serum chemistry panel was obtained weekly. The primary end points were the constipation response (based on the change from baseline in weekly number of BMs) and the global sense response (based on daily scores for the patient's overall sense of change in their bowel problems). RESULTS: At randomization, there were 18 patients in group A and 25 in group B. Of these, 40 patients (16 group A, 24 group B) had > or 7 days of diary information while taking study treatment and were evaluable for efficacy. The constipation response rate was 100% in group A and 95.8% in group B, and the respective global sense response rates were 68.8% and 79.2%. Four patients in group B withdrew due to adverse events, none of which were serious. Five patients had occasional hypokalemia that required no treatment. Changes from baseline in serum concentrations of calcium, inorganic phosphorus, and potassium were not clinically significant and did not require treatment. CONCLUSIONS: In this small study, NaP tablets taken daily were generally well tolerated (particularly in the low-dose group) and produced prompt relief of constipation--generally within the first week of treatment--that was sustained over the 28-day treatment period. A reasonable starting dose appears to be 2 to 4 tablets (3-6 g NaP) daily

BACKGROUND: Repifermin (keratinocyte growth factor-2) has been shown to reduce inflammation in animal models of colitis. AIM: To evaluate repifermin for the treatment of active ulcerative colitis. METHODS: Eighty-eight patients with active ulcerative colitis were enrolled in a 6-week, double-blind trial. Patients were randomized to receive treatment for five consecutive days with intravenous repifermin at a dose of 1, 5, 10, 25 or 50 microg/kg, or placebo. The primary objective of the study was to evaluate the safety of repifermin. The primary efficacy outcome was clinical remission at week 4, defined as a score of zero on the endoscopic appearance and stool blood components of the Mayo score and a score of zero or unity on the stool frequency and physician's global assessment components. RESULTS: At week 4, the rates of clinical remission in the 1, 5, 10, 25 and 50 microg/kg repifermin groups were 19%, 9%, 0%, 0% and 0%, respectively, and 11% for the placebo group (P = 0.32 for repifermin vs. placebo). The frequencies of commonly occurring adverse events and severe adverse events were similar in both groups. CONCLUSIONS: Intravenous repifermin at a dose of 1-50 microg/kg was very well tolerated, but there was no evidence that repifermin was effective for the treatment of active ulcerative colitis at these doses. An additional study to determine the efficacy of repifermin at doses of > 50 microg/kg or for a longer treatment duration may be warranted, as the maximally tolerated dose was not reached in the present study.

Extraintestinal manifestations of both Crohn's disease and ulcerative colitis (UC) have been well described, although pulmonary findings are often overlooked. We summarize the experience of more than 400 cases of pulmonary manifestations of inflammatory bowel disease (IBD). These manifestations will be categorized by disease mechanism into drug-induced disease, anatomic disease, over-lap syndromes, autoimmune disease, physiologic consequences of IBD, pulmonary function test abnormalities, and nonspecific lung disease. We intend to provide the clinician with a practical working update on the spectrum of pulmonary dysfunction associated with IBD