Bigger Data Needed and Other IBD Updates April 2020

R Pittayanon et al. Gastroenterol 2020; 158: 930-46.  In this systematic review of the relationship between gut microbiota and inflammatory bowel disease, 48 studies and 45 articles were included from a total of 2631 citations.  Overall, the authors found inconsistent results with differences in the abundances of some bacteria in IBD. My take: These microbiota studies use ‘big data’ to look for abnormal patterns in patients with IBD.  Overall, most of these studies support a reduced diversity among patients with IBD.  Specific variation in microbes varies widely and remains unclear if they are a cause or a consequence of IBD.

J Piercy et al. JPGN 2020; 70: 318-23. Among 90 adolescents with IBD, “perfectionistic concerns (self-critical and socially prescribed perfectionism) were associated with higher rates of adolescent-reported externalizing symptoms” Thus, perfectionism may help with self-management but lead to more stress and psychosocial symptoms.

S Jardine et al. Gastroenterol 2020; 158: 1000-15. This study used both TTC7A-knockout cells and a zebrafish model to screen compounds that have been FDA approved for treatment of inflammatory bowel disease caused by TTC7A deficiency.  The authors identified leflunomide that reduces apotosis and levels of active caspase 3 in TTC-7A-knockout cells and restored gut motility along with improvement of intestinal cell survival in zebrafish. This study has some amazing figures detailing the changes induced by leflunomide. My take: Although some centers have offered hematopoetic stem cell transplant (with dismal results), there is NOT a currently accepted treatment for TTC7A deficiency-induced IBD.  This study suggests an agent which may help.

CLD Prevost et al. AP&T 2020. https://doi.org/10.1111/apt.15681 Key finding:  Among patients exposed to anti‐TNF, the Lémann Index was lower in those who were exposed in the first 2 years of their disease (P = 0.015).  My take: Early treatment with anti-TNF agents can reduce risk of permanent bowel damage. This was seen as well in the RISK study which showed that anti-TNF therapy reduced the development of penetrating disease. (Related post: CCFA Update 2017, Part 3)

Full link: Bowel damage and disability in Crohn’s disease: a prospective study in a tertiary referral centre of the Lémann Index and Inflammatory Bowel Disease Disability Index

What I did not know …a few items

  1. 6-Mercaptopurine (6-MP) often can be used when patients are intolerant of azathioprineS Hubener et al. Clin Gastroenterol Hepatol 2016; 14: 445-53.  This retrospective study showed that 15 of 20 patients with autoimmune hepatitis and prior azathioprine intolerance responded to 6-MP.  This is somewhat unexpected as azathioprine is metabolized into 6-MP.  However, rather than 6-thiouracil, the “imidazol component of azathioprine, which is cleaved off…might trigger adverse reactions.”  Another artical on thiopurines (Aliment Pharmacol Ther 2016; 43: 863-883) (thanks to Ben God for this reference) provides a thorough review of the pharmacogenetics and pharmocokinetics of these medications.  While this review reinforces the recommendation to check TPMT before treatment, it notes that only a small proportion of thiopurine toxicity is related to deficient TPMT activity.
  2. There is no formal validated or consensus definitions of mild, moderate, or severe IBD. L Peyrin-Biroulet et al. Clin Gastroenterol Hepatol 2016; 14: 348-54.  While the Lemann index measures the cumulative structural bowel disease, the authors propose criteria which involves three areas of severity: impact of the disease on the patient (eg. clinical symptoms), inflammatory burden (eg. biomarkers, mucosal disease, disease extent), and disease course (eg. structural disease, intestinal resection, perianal disease, extraintestinal manifestations)
  3. Fundic gland polyps (often associated with proton pump inhibitor therapy) are not premalignant lesions. There is an “inverse correlation between the FGPs and gastric neoplasia.” S Varghese et al. Gastroenterol Hepatol; 2016; 12: 153-4.
  4. Parents of newborns do not know how to use car seats.  BD Hoffman et al (J Pediatr 2016; 171: 48-54) showed that 95% of car seats were misused (291 families).  Serious misuse was present in 91%.

 

Related blog posts: Lemann index: Short Takes on IBD Articles | gutsandgrowth

Gibbs Gardens has >20 million daffodils

Gibbs Gardens has >20 million daffodils

Short Takes on IBD Articles

Singh S, et al. Gastroenterol 2015; 148: 64-76.  In this study, the authors identified 21 trials with 2006 participants to examine the comparative efficacy of pharmacologic interventions to prevent relapse of Crohn’s disease (CD) after surgery.  Conclusion: “anti-TNF monotherapy appears to be the most effective strategy for postoperative prophylaxis for CD.” The relative risk of clinical relapse and endoscopic relapse with anti-TNF monotherapy was estimated to be between 0.02-0.20 and 0.005-0.04, respectively. Thus, those at highest risk for recurrence, including younger individuals, smokers, penetrating CD, perianal CD, and recurrent surgeries) are most likely to benefit.(Related blog post: More Lessons in TNF Therapy (Part 1) | gutsandgrowth)

Pariente B, et al. Gastroenterol 2015; 148: 52-63. The researchers in this cross-sectional study developed the Lémann Index which measures cumulative structural bowel damage in patients with CD.  My only complaint with this study was the associated editorial on pages 8-10, titled “The Holy Grail, or Only Half Way There?”  There are too many medical advances compared to ‘the holy grail’ and, in my opinion, this shouldn’t be one of them.

Zitomersky NL et al. Inflamm Bowel Dis 2015; 21: 307-14.  In this study the authors examine the relationship between the development of antibodies to infliximab (ATI) and the risk of surgery in a cross-sectional cohort of pediatric and young adult patients.  Not surprisingly, development of ATI, which was noted in 20% of cohort, correlated with reductions in infliximab levels and higher risk of surgery.  Interestingly, prior (but not current) immunomodulator therapy was associated with lower antibody levels (P=0.007).  Perhaps, “step-up” therapy may lower the risk of ATI. (This was a point noted by James Markowitz in a previous post: More NASPGHAN Meeting Notes: IBD Hot Topics | gutsandgrowth)

Rogler G, Vavricka S. Inflamm Bowel Dis 2015; 21: 400-08. This review article discusses the exposome in IBD.  Exposures include air pollution, diet, drugs, infections, water pollution, food additives, and smoking.  These exposures influence the gut microbiome and genetic susceptibility. “Only environmental influences…explain the rising incidence in IBD worldwide. The investigation of the exposome…is an enormous challenge…[but] of crucial importance.” (Related blog post: What do you know about the “exposome”? | gutsandgrowth)

Kalmon RS. Inflamm Bowel Dis 2015; 21: 428-35. Review article provides information when there is a prior personal or family history of malignancy (=avoid thiopurines).  Figure 2 is a suggested algorithm for those with IBD and a previous diagnosis of cancer.

  • In those in which the cancer is adequately controlled, the recommendations indicate that if it has been more than 2 years since completion of therapy to use a ‘step-up’ management and favor methotrexate over thiopurines
  • In those with less than 2 years since completion of cancer treatment and not responsive to 5-ASAs/antibiotics, then “consider monotherapy with biologic agents.”
  • In those still receiving chemotherapy, the authors suggest “hold immunosuppression and follow course of IBD.  If IBD not well controlled despite chemotherapy, 5-ASAs and antibiotics, treat flares with steroids, then consider biologic agents.”