• Reference [15]
ACG 2018 Crohn's disease treatment recommendations
Mild-to-moderate active disease
  • Definition: (CDAI score of 150 - 220) ambulatory and able to tolerate oral alimentation without manifestations of dehydration, systemic toxicity (high fevers, rigors, and prostration), abdominal tenderness, painful mass, intestinal obstruction, or > 10% weight loss. These individuals do not have severe endoscopic lesions.
  • Treatment options
  • Not recommended
    • Mesalamine, metronidazole, ciprofloxacin, antimycobacterial therapy
Moderate-to-severe active disease
  • Definition: (CDAI score of 220 - 450) prominent symptoms of fever, significant weight loss, abdominal pain or tenderness, intermittent nausea or vomiting (without obstructive findings), or significant anemia. They typically have moderate to severely active endoscopic mucosal disease.
  • Treatment options
  • Adjunctive or steroid-sparing treatment
    • Azathioprine, 6-MP, or methotrexate - clinical response can take up to 12 weeks so they are not effective for inducing remission. These agents can be used as adjunctive therapy for reducing immunogenicity against biologic therapy (6-mercaptopurine or azathioprine typically at reduced doses and methotrexate 12.5–15 mg orally once weekly)
    • Combination therapy of infliximab with immunomodulators (azathioprine, 6-MP) is more effective than treatment with either immunomodulators alone or infliximab alone in patients who are naive to those agents
  • Not recommended
    • Cyclosporine, tacrolimus, and mycophenolate mofetil
Severe/fulminant active disease
Fistulizing disease
Maintenance of remission
  • Definition: (CDAI score < 150) asymptomatic
  • Recommended treatment
    • In general, patients should continue therapy with the drug that was used to induce remission. If corticosteroids were used, patients should be transitioned to azathioprine, 6-MP, or methotrexate
    • Budesonide (Entocort®) should not be used to maintain remission beyond 4 months
  • Not recommended
    • Sulfasalazine, olsalazine

  • Prednisone is given until resolution of symptoms which typically occurs within 7 - 28 days. It is then tapered by 5 - 10 mg/week down to 20 mg. From 20 mg, it is tapered by 2.5 - 5 mg/week until stopped.
  • Reference [3,14,15]
AGA 2014 Crohn's disease treatment recommendations
Initial therapy
  • Mild disease - no systemic symptoms; CDAI score 150 - 220
    • Ileum and/or proximal colon involvement
    • Diffuse or left colon
      • Prednisone 40 - 60 mg once daily ± azathioprine 2 - 3 mg/kg/day

Maintenance of remission
  • Mild disease - no systemic symptoms; CDAI score 150 - 220
    • Option 1 - stop therapy; this option has a high relapse rate
    • Option 2 - budesonide 6 mg/day; time to relapse is prolonged; remission rates are similar to placebo at 1 year
    • Option 3

Refractory disease


  • Reference [16]
Evaluating patients who fail treatment while on TNF inhibitor therapy
Step 1 - Check trough TNF inhibitor levels
  • Target trough levels for TNF inhibitors:
    • Adalimumab (Humira®): ≥ 7.5 mcg/ml
    • Certolizumab Pegol (Cimzia®): ≥ 20 mcg/ml
    • Golimumab (Simponi®): unknown
    • Infliximab (Remicade®): ≥ 5 mcg/ml
Step 2
  • If trough levels are adequate, suspect drug failure and consider switching to another drug class
  • If trough levels are low, check for anti-drug antibodies
    • Low/absent trough with no anti-drug antibodies
      • Possible pharmacokinetic failure
      • Shorten dosing interval, and/or increase dose, and/or add immunosuppressant
    • Absent trough with high-titer anti-drug antibodies
      • Possible immune-mediated failure
      • Change to another TNF inhibitor or use a different class
    • Low trough with low- or high-titer anti-drug antibodies
      • Indeterminate. Consider one of the above approaches.


  • Reference [13]
CDAI score
The value for each item is multiplied by its weight. The weighted values are then added up for the CDAI score.
Item Weight
(multiply item value by this number)
Total number of liquid or very soft stools over last 7 days 2
Degree of abdominal pain over last 7 days
  • Scale: 0 - none, 1 - mild, 2 - moderate, 3 - severe
  • Assign a value for each day and sum the values
5
General well-being over last 7 days
  • Scale: 0 - well, 1 - below normal, 2 - poor, 3 - very poor, 4 - terrible)
  • Assign a value for each day and sum the values
7
Presence of the following (one point for each):
  • Arthritis/arthralgia
  • Mucocutaneous lesions (e.g. erythema nodosum,
    aphthous ulcers)
  • Iritis/Uveitis
  • Anal disease (e.g. fistula, fissure, etc.)
  • Fistula (cutaneous, vesicular, vaginal, etc.)
  • Fever (> 100.04°F, 37.8°C) in past week
20
Use of antidiarrheal in last week
(Yes - 1, No - 0)
30
Abdominal mass
  • Scale: 0 - none, 2 - questionable, 5 - definite
10
Hematocrit (Hct) below normal
Males
  • 47 minus current Hct
Females
  • 42 minus current Hct
6
Percent weight loss
(Healthy weight - current weight)/Healthy weight X 100
1


  • Reference [3]
CDAI score Disease activity
< 150 Remission
150 - 220 Mild-moderate disease
220 - 450 Moderate-severe disease
> 450 Severe-fulminant