Background: Mycobacterium avium subspecies paratuberculosis is probably the best candidate for a microbial cause of Crohn's disease although arguments to the contrary can be equally convincing. Growing evidence suggests that prolonged antimycobacterial combination therapy can improve Crohn's disease in some patients.
Aim: To report long-term observations in patients with severe Crohn's disease treated with triple macrolide-based antimycobacterial therapy.
Patients: A series of 12 patients (7 male, 5 female; aged 15-42 years) with severe, obstructive or penetrating Crohn's disease were recruited.
Methods: Patients failing maximal therapy were commenced prospectively on a combination of rifabutin (450 mg/d), clarithromycin (750 mg/d) and clofazimine (2 mg/kg/d). Progress was monitored through colonoscopy, histology, clinical response and Harvey-Bradshaw activity index.
Results: Follow-up data were available for up to 54 months of therapy Six out of 12 patients experienced a full response to the antiMycobacterium avium subspecies paratuberculosis combination achieving complete clinical, colonoscopic and histologic remission of Crohn's disease. Four of these patients were able to cease treatment after 24-46 months, 3 of whom remained in total remission without treatment for up to 26 months and one patient relapsed after six months off treatment. A partial response to the anti-Mycobacterium avium subspecies paratuberculosis combination was seen in 2 patients showing complete clinical remission with mild histologic inflammation. Return to normal of terminal ileal strictures occurred in 5 patients. Harvey-Bradshaw activity index in patients showing a full or partial response to therapy fell from an initial 13.4 +/- 1. 91 to 0. 5 +/- 0. 47 [n = 8, p < 0. 001) after 52-54 months.
Conclusions: Reversal of severe Crohn's disease has been achieved in 6/12 patients using prolonged combination anti-Mycobacterium avium subspecies paratuberculosis therapy alone. Three patients remain in long-term remission with no detectable Crohn's disease off all therapy These results support a causal role for Mycobacterium avium subspecies paratuberculosis in Crohn's disease while also suggesting that a cure may become possible.