CMV Colitis Rarely Identified

Q Buck et al. JPGN 2022; 75: 462-465. Routine Histology-Based Diagnosis of CMV Colitis Was Rare in Pediatric Patients

Key findings from this retrospective review (2011-2019):

  • Of 1801 cases of histologic colitis, 11 patients had CMV found by histology (mean age 15.4, 72.7% female), with an incidence of 0.6%
  • Nine out of these 11 (81.8%) patients were immunocompromised and 4 (36.4%) had inflammatory bowel disease (IBD) as an underlying diagnosis of whom 2 had new-onset ulcerative colitis
  • 5 of 6 post-transplant patients with CMV colitis had preexisting CMV viremia
  • An independent analysis of 54 consecutive IBD-associated colectomy cases at TCH showed no histologic evidence of CMV

The study finding that half of the cases of CMV in the IBD population were identified prior to treatment indicates that the underlying IBD may be a more important susceptibility factor than the immunosuppressive medications.

My take: This study indicates that CMV colitis remains important in the post-transplant population but is rarely consequential in the pediatric IBD population.

Related blog posts:

Little O’Malley Peak Trail, near Anchorage AK.
Denali is visible in background, even though it is ~180 miles away.

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Precision Dosing with Vedolizumab in Pediatrics

RJ Colman et al. AP&T 2022; https://doi.org/10.1111/apt.17277. Open access! Real world population pharmacokinetic study in children and young adults with inflammatory bowel disease discovers novel blood and stool microbial predictors of vedolizumab clearance

“The study included data from 463 observed vedolizumab concentrations (59 peaks and 404 troughs) from 74 patients with IBD (52 with Crohn’s disease and 22 with ulcerative colitis or unclassified IBD, median age 16 years)…This study was part of the multicentre REFINE study, which aimed to investigate paediatric PK factors among different biological therapies. Both induction and maintenance doses were between 6 and 10 mg/kg for patients less than 30 kg and 300 mg for patients above 30 kg.”

Key findings:

  • “Using the new model in a simulation analysis of standard vedolizumab infusions (0, 2 and 6 weeks followed by every 8 weeks), we demonstrate that the expected cTrough at week 22 (infusion-5) in the majority of patients would result in drug exposure below current cTrough targets..The dosing simulations in our current study found that receiving standard dosing would lead to <20% of patients achieving a cTrough of 20 μg/ml at infusion-5.”
  • “The severity of hypoalbuminemia resulted in higher drug CL (lower cTrough) than the inflammatory burden (elevated ESR).”
  • Infusion-3 cTrough of at least 37 μg/ml and infusion-4 cTrough of at least 20 μg/ml best predicted SFCR (steroid-free clinical remission) at infusion-4. In contrast, we showed inadequate drug exposure during induction (AUCweek 14 of <134,580 μg h/ml) was associated with clinical non-response

My take: This study shows that therapeutic drug monitoring (TDM) is likely to be beneficial in improving outcomes in pediatric patients receiving vedolizumab. Low albumin in particular is associated with increased drug clearance. From this study, it looks like most pediatric patients will need dosing every 4 to 6 weeks to achieve good levels. The authors in their discussion reinforce the utility of TDM to “guide anti-TNF dose optimisations has been shown to improve durability and reduce both immunogenicity and loss of response.”

References:

13 Dubinsky MC, Mendiolaza ML, Phan BL, Moran HR, Tse SS, Mould DR. Dashboard-driven accelerated infliximab induction dosing increases infliximab durability and reduces immunogenicity. Inflamm Bowel Dis. 2022; 28: 1375– 85.

51 Strik AS, Löwenberg M, Mould DR, Berends SE, Ponsioen CI, van den Brande JMH, et al. Efficacy of dashboard driven dosing of infliximab in inflammatory bowel disease patients: a randomized controlled trial. Scand J Gastroenterol 2021; 56: 145– 154.

Related blog posts:

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Rethinking the Link between NSAIDs and IBD Flares

This is the 4000th blog post for GutsandGrowth!

S Cohen-Meckelburg et al. American Journal of Gastroenterology 2022: doi:10.14309/ajg.0000000000001932. The association between non-steroidal anti-inflammatory drug use and inflammatory bowel disease exacerbations: a true association or residual bias?

Background: NSAIDs are well-known to cause gastrointestinal injury. While single center studies have suggested that NSAIDs are associated with increased IBD flares, a systemic review of 18 studies found no consistent association between NSAIDs and IBD exacerbation.

This study included 15,705 (44.8%) and 19,326 (55.2%) IBD patients with and without an NSAID exposure.

Key findings:

  • Findings from a Cox proportional hazards model suggest an association between NSAIDs and IBD exacerbation (HR 1.24; 95%CI 1.16-1.33)
  • However, the likelihood of an IBD exacerbation in the NSAID exposed arm preceding NSAID exposure was similar (HR 1.30; 95%CI 1.21-1.39).
  • Those who received NSAIDs were already at increased risk of experiencing a disease flare. And the prior event rate ratio for IBD exacerbation, as determined by dividing the adjusted HR after NSAID exposure by the adjusted HR for pre-NSAID exposure, was 0.95 (95% CI, 0.89 – 1.01).
  • “A self-controlled case series analysis of 3,968 patients who had both an NSAID exposure and IBD exacerbation demonstrated similar exacerbation rates in the 1-year preceding exposure, 2-6 weeks post-exposure, and 6-weeks to 6-months post-exposure, but higher incidence 0-2 weeks post-exposure, suggesting potential confounding by reverse causality.” The self-controlled part of the study allowed patients to serve as their own controls which allowed adjustment for many factors that are difficult to control with retrospective studies.
  • 75% of patients with IBD who were prescribed an NSAID did not have an IBD exacerbation during a mean of 5.9 years of follow-up
  • NSAIDs were commonly used: 36.5% of patients with IBD had received at least one NSAID prescription
  • NSAIDs use was prescribed more frequently in patients with immune targeted therapy (likely a marker for moderate to severe disease)

Discussion points:

  • The estimated prior event ratio of 0.95 suggests that the risk of IBD flares in NSAID-exposed patients preceded the use of NSAIDs. The risk of IBD exacerbation did not increase in the 2 weeks to 6 months after NSAID exposure.
  • The overall association of increased IBD flare is likely related to reverse causation. Patients may take NSAIDs due to arthropathy or other symptoms that may be an early manifestation of a flare.

My take: This study challenges the prevailing view that NSAID use worsen inflammatory bowel disease; it is more likely that IBD exacerbations are due to underlying risk from more severe disease and residual confounding/reverse causality. The study provides reassurance that short-duration use is likely to be well-tolerated in most patients with IBD.

Medscape Gastroenterology (summary of this study): Reassuring Data on NSAIDs in IBD Flares

Mt Hood (picture from a friend)

CHOA Pediatric Thickener Guide & High Rate of U.S. Gun Violence

U.S. (in 2015) with much higher gun deaths than any other developed country.

Related blog posts:

This guide reviews the common thickeners including SimplyThick, Nestle ThickenUp Clear, Hormel: Thick & Easy Clear, Gelmix (see below), Purathick, DysphagiAide, Thick-It, Gerber Rice Cereal, Beechnut Oatmeal Cereal

Portage Pass, AK

Kids Are Different: Therapeutic Drug Monitoring

NH Nguyen et al. Gastroenterol 2022; 163: 937-949. Open Access! Proactive Therapeutic Drug Monitoring Versus Conventional Management for Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis

Key finding:

  • On meta-analysis of 9 RCTs (8 RCTs in adults, and focusing on maintenance phase), there was no significant difference in the risk of failing to maintain clinical remission in patients who underwent proactive TDM (267/709; 38%) vs conventional management (292/696; 42%) (relative risk [RR], 0.96)

The discussion in this paper makes some important points, as there are some populations in which proactive TDM is more likely to be beneficial.

Pediatrics:

“The impact of proactive TDM in pediatric patients also merits further consideration. This concept may be particularly important in pediatrics due to the variability in size of patients, which may not be adequately addressed by weight-based dosing.33 This is especially important in younger children, where it has been shown that standard TNFα antagonist regimens and trough levels may not be applicable in this age group, and may require more frequent escalation of therapy.34,35 In the PAILOT trial, proactive TDM in children with clinical response to adalimumab was associated with higher rates of maintaining sustained corticosteroid-free clinical remission at all visits from week 8–72, compared with reactive TDM in which physicians were informed of trough concentration only after loss of response.”

Induction Dosing (Adults and Children):

“It is possible that the early measurement of biologic drug concentrations, to identify patients who may have accelerated clearance, and optimization of a subset of these patients early in the course of therapy may offer benefit.1,30 …Ongoing trials such as OPTIMIZE (NCT04835506) and TITRATE (NCT03937609) in which infliximab is optimized during the induction phase through a pharmacokinetic dashboard in patients with Crohn’s disease and acute severe ulcerative colitis will shed further light on this.”

My take: So far, studies in adults have not shown that proactive therapeutic drug monitoring has been effective in improving clinical outcomes. This may change particularly if studies focus on patients on monotherapy who are at increased risk of subtherapeutic levels. No matter what happens in adults, there is sufficient data showing that proactive therapeutic drug monitoring is essential in children. This is especially important as ‘routine” dosing of infliximab in children may be subtherapeutic in nearly 80%.

Related blog posts:

Updated Health Warnings Needed For Alcohol & More on COVID-19/Paxlovid

AH Grummon, MG Hall. NEJM 2022; 387: 772-774. Updated Health Warnings for Alcohol — Informing Consumers and Reducing Harm

This article makes a compelling case that most U.S. consumers do not know the true risks of alcohol intake; this is likely in part due to the >$1 billion spent each year on marketing by the alcohol industry.

Leading causes of alcohol-related harms:

  • Fatal and nonfatal injuries resulting from acute intoxication (including injuries caused by motor vehicle crashes)
  • Chronic diseases including hypertensive heart disease, cirrhosis, pancreatitis and several types of cancer.2 Even light or moderate drinking increases the risk of these conditions, particularly cancer (eg. breast, colon, and stomach)2
  • Risks during pregnancy include miscarriage, preterm birth, and fetal alcohol syndrome (these risks are not specifically addressed in this commentary)
  • Also not noted in this article, alcohol is considered a major contributor to violence, including intimate partner violence

Key points –Scope of Problem and Informing Consumers:

  • “In April 2022, the Centers for Disease Control and Prevention (CDC) released new mortality statistics showing that alcohol consumption now accounts for more than 140,000 deaths per year in the United States, or more than 380 deaths per day. The Covid-19 pandemic has exacerbated alcohol-associated harm in the United States, with alcohol-related deaths increasing by 25% during the first year of the pandemic as compared with the previous year”(White AM, Castle IP, Powell PA, Hingson RW, Koob GF. Alcohol-related deaths during the Covid-19 pandemic. JAMA 2022;327:1704-1706).
  • “A national survey of U.S. adults, for example, found that nearly 70% are unaware that alcohol consumption increases the risk of cancer.3…Some alcohol companies even seek to link their products to health campaigns. Several companies, for example, have sold seasonal, pink ribbon–themed alcoholic drinks during October to promote their efforts to raise funds for breast-cancer research — despite compelling evidence that alcohol increases the risk of developing breast cancer.”
  • The authors advocate for better warning labels. They argue that “updated alcohol warnings would provide new risk information to many Americans, … implementing such warnings would be a sensible policy for addressing industry dominance over alcohol-related information, even if warnings’ effects on consumption are fairly small.”

Related article: NBC News 11/4/22: Alcohol deaths spiked among middle-aged adults, especially women, during pandemic “Alcohol-related deaths rose by 26% from 2019 to 2020, a new report published Friday by the Centers for Disease Control and Prevention finds.”

Related blog post:

More on COVID-19:

Eric Topol: Paxlovid and Long Covid This in-depth article reviews the benefits of paxlovid (early) and later, including the reduction of Long Covid in 26% in a recent study. It also provides a table for potential drug interactions (Thanks to Jeff Lewis for sharing).

This recent study is reviewed in NY Times (11/7/22): Paxlovid May Reduce Risk of Long Covid in Eligible Patients, Study Finds

Leaning Tower of Niles (1934) (near Chicago, IL). The “Papa Chris Place” sign should help distinguish this landmark for the one in Pisa.

IgA Vasculitis (Henoch-Schonlein Purpura)

CD Lee et al. NEJM 2022; 387: 833-838. Telescoping the Diagnostic Process

This clinical problem-solving case:  “3-year-old boy was brought to the hospital with a 4-day history of vomiting and abdominal pain in the left lower quadrant. He had associated chills without fever, nonbloody and nonbilious emesis, constipation, reduced urinary output, and a decreased activity level.” He developed a rash more than 5 days after presentation.

This turns out to be a good review of IgA Vasculitis (HSP).

A few excerpts:

IgA vasculitis is the most common vasculitis of childhood.1 The disease is classified as a small-vessel vasculitis and most commonly affects White and Asian children, with a slight male predominance. It results from the deposition of IgA immune complexes in involved organ systems and is preceded by infection in most patients.2 This is perhaps unsurprising given the primary function of IgA in mucosal immunity. The most commonly implicated organism is group A β-hemolytic streptococcus.1

IgA vasculitis primarily involves the skin, gastrointestinal tract, joints, and kidneys, with involvement in 95%, 70%, 70 to 90%, and 40 to 50% of cases, respectively, in case series3; other data suggest that kidney involvement is even more common, with microhematuria present in the majority of patients.4 Less common manifestations include orchitis (in 14% of male patients) and, in rare cases, central nervous system involvement.3 Skin involvement is almost universal; a petechial or purpuric rash in dependent areas (typically the buttocks and lower legs) is the classic manifestation, but other skin manifestations, including bullae, edema, and necrosis, can be seen.1,3 

IgA vasculitis affecting the gastrointestinal tract can manifest as upper or lower gastrointestinal bleeding. Bowel edema can create a lead point, causing intussusception in up to 3% of patients, as occurred in our patient.1 …In the majority of cases, the rash precedes the onset of gastrointestinal symptoms; our patient was among the minority (approximately 25%) of patients in whom this order is reversed.5 Rare gastrointestinal complications include bowel infarction, perforation, strictures, and protein-losing enteropathy.2,5

Related blog post: Henoch-Schonlein Purpura and Neurologic Manifestations

Non-blanching petechiae

Therapeutic Endoscopy Rarely Beneficial in Infants with Gastrointestinal Bleeding

P Bose et al. JPGN 2022; 75: 514-520. Endoscopy in Infants With Gastrointestinal Bleeding Has Limited Diagnostic or Therapeutic Benefit

I read this article shortly after convincing a surgical colleague to explore a well-appearing 6 month old with gastrointestinal bleeding for a Meckel’s diverticulum rather than undergo endoscopy.

In this retrospective cohort study of hospitalized infants (n=56, =/< 12 months) with gastrointestinal bleeding, the authors reviewed endoscopic procedures (EGD, Colonoscopy, Flexible Sigmoidoscopy) with respect to identifying diagnosis and in terms of outcomes.

Key points:

  • Seven endoscopies identified sources of GIB: gastric ulcers, a duodenal ulcer, gastric angiodysplasia, esophageal varices, and an anastomotic ulcer.
  • Intervention for bleeding control occurred in just 3 cases (5.4%); two of these had liver disease.
  • Most (55%) had no abnormalities on endoscopy
  • The authors detail two fatal cases in which GIB started in the first week of life. Both had complications occurring within 3 hours of endoscopy, one with a gastric perforation and one with necrotizing enterocolitis.

My take: Endoscopy in infants with GIB is rarely beneficial. Supportive care and surgical interventions should be considered, especially in those without underlying liver disease.

Related blog posts:

Savage Alpine Trail at Denali National Park. Parts of Denali can be seen in the background

Disclaimer: This blog, gutsandgrowth, assumes no responsibility for any use or operation of any method, product, instruction, concept or idea contained in the material herein or for any injury or damage to persons or property (whether products liability, negligence or otherwise) resulting from such use or operation. These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  Because of rapid advances in the medical sciences, the gutsandgrowth blog cautions that independent verification should be made of diagnosis and drug dosages. The reader is solely responsible for the conduct of any suggested test or procedure.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Is Reflux Really a Disease in Premature Infants?

From Atlanta Botanical Garden

Z Sultana et al. Gastro Hep Advances 2022; 1: 869-881: Open Access! Symptom Scores and pH-Impedance: Secondary Analysis of a Randomized Controlled Trial in Infants Treated for Gastroesophageal Reflux

In the introduction, the authors note: “Gastroesophageal reflux (GER) is a physiological process defined as the passage of gastric contents into the esophagus with or without regurgitation and vomiting, while GER disease (GERD) is pathophysiologic and occurs when GER is associated with troublesome symptoms and/or complications.”

“This distinction between GER and GERD remains enigmatic among survivors in the neonatal intensive care unit (NICU). Reflux-type symptoms (arching, irritability, acute life-threatening events, coughing, failure to thrive, and swallowing difficulties) in this high-risk infant population can be troublesome to the parent and provider, and empiric management using pharmacological and dietary changes are common albeit with consequences.”

Methods: “Infant Gastroesophageal Reflux Questionnaire Revised (I-GERQ-R) and 24-hour pH-impedance data were analyzed from 94 infants…[and] Longitudinal data from 40 infants that received randomized GER therapy (proton pump inhibitor [PPI] with or without feeding modifications) for 4 weeks followed by 1-week washout were analyzed. Relationships between I-GERQ-R and pH-impedance metrics (acid reflux index, acid and bolus GER events, distal baseline impedance, and symptoms) were examined and effects of treatments compared.”

Key findings:

  • Acid-suppressive therapy with feeding modifications had no effect on symptom scores or pH-impedance metrics. Clearance of refluxate worsened despite PPI therapy.
  • Correlations between I-GERQ-R and pH-impedance metrics were weak or non-existent, indicating that physicians cannot depend only on the questionnaire to diagnose and treat GERD in premature infants.

My take: This study shows that reflux symptoms are unreliable in establishing a diagnosis of reflux disease in infants. In addition, medical treatments were not beneficial in infants with abnormal pH-impedance metrics. Perhaps, it is time to acknowledge that we cannot even agree what reflux “disease” is in (premature) infants.

Related blog posts:

Terrain in Denali National Park, AK