Introduction

Crohn's disease (CD) is a recurrent, chronic inflammatory disorder that falls under the category of Inflammatory Bowel Diseases (IBD). Environmental factors, the immune system, the gut microbiota, and genetics interact to induce CD.¹ The disease progresses through times of growth and development, so children are particularly susceptible and account for approximately 25% of all CD cases.^2,3 

Diarrhoea and stomach discomfort are common symptoms. The significant correlation between the increasing prevalence of paediatric CD and diets becoming more westernised, which results in dysbiosis (altered gut microbiota), is a major cause for concern. The western diet frequently lacks nutritional fibre, fruits, and vegetables and is abundant in processed foods, fat, sugar, and additives.²

In paediatric CD, growth and development are frequently seen to be delayed. Most present with a history of weight loss or plateaued weight gain. This results from intestinal malabsorption and reduced nutritional intake.^3,4 Delays in pubertal development and impaired linear growth are common.³ The Paediatric Crohn's Disease Activity Index (PCDAI) evaluates growth parameters, physical examination results, and laboratory tests. It is a measure used in clinical practice and research to identify remission, measure the severity of the disease, and examine how efficiently treatments affect paediatric patients with CD.¹ 

Diet-based treatments, especially Exclusive Enteral Nutrition (EEN), are a fundamental alternative to traditional medications such as corticosteroids. These dietary approaches are highlighted because they address important aspects of CD development by addressing gut dysbiosis and intestinal inflammation in addition to treating the nutritional deficiencies.⁵

What is exclusive enteral nutrition (EEN)?

EEN involves the use of a comprehensive liquid formula diet that contains all the necessary nutritional requirements and lasts for approximately six to eight weeks.² The main types of EEN formula available are distinguished primarily by the complexity of the proteins and fats they contain. Polymeric formulas contain whole proteins, semi-elemental formulas contain partially broken down proteins (peptides) and elemental formulas contain fully broken down proteins (individual amino acids). 

Although the polymeric formula is preferred clinically (primarily due to increased palatability from flavourings which provide a better taste, leading to increased compliance and a lower cost compared to the other formulas), the overall effectiveness of EEN in inducing remission is independent of the formula type.^1,2 Although the liquid formula is often given orally, a nasogastric tube may be used to guarantee compliance or if the patient is unable to consume the recommended daily calorie intake.^2,3 EEN reduces gut inflammation, alters intestinal microbiota and improves intestinal barrier function.²

Effectiveness of EEN in pediatric crohn’s disease

EEN is highly efficacious, leading to clinical remission in approximately 75-85% of pediatric patients with mild to moderate CD. Compared to corticosteroids, EEN has a reduced incidence of side effects and fewer adverse events, indicating an exceptional safety profile. Growth retardation and decreased bone development are two adverse consequences of corticosteroids that EEN prevents. Approximately 50% of CD patients may avoid steroids for the rest of their lives if EEN is used during their early years of development.^1,2,5

Advantages of EEN

• Avoids steroid-related side effects ^1,2,5
• Provides complete nutrition²
• Encourages mucosal healing, which is important since it indicates positive long-term clinical outcomes^1,3
• Promotes weight increase and improves muscle mass, bone health, and bone metabolism ^1,5

Limitations and challenges

• Acceptability among patients and their families is the main obstacle;the strict requirement to abstain from solid food causes problems with compliance^2,5
• Long-term compliance may be difficult due to taste and palatability issues as well as cost and availability of formulas³
• After EEN therapy, a common issue is the quick loss of responsiveness and recurrence of inflammation upon food reintroduction²

Comparison with other dietary strategies

EEN is the recommended first-line therapy for inducing remission in mild to moderate pediatric CD,⁵ However, the rapid rate of relapse following food reintroduction and the limits of EEN compliance have led to research and development of more patient-friendly dietary strategies, such as Partial Enteral Nutrition (PEN). PEN can also be combined with the Crohn's Disease Exclusion Diet (CDED). Another strategy is CD Treatment with Eating Diet (CD-TREAT).

PEN

• Uses a liquid formula for less than 100% of caloric demands
• PEN alone is not recommended for the induction of remission in active CD as it is significantly less potent than EEN
• EEN is better at enabling clinical remission 
• In contrast to EEN, which suppresses inflammation, PEN's clinical improvements were mostly ascribed to nutritional advantages
• PEN can be used to prolong remission or act as a short-term bridge between therapies^1,2,5

PEN + CDED

• PEN and CDED (a whole-food diet) limit exposure to substances that may have adverse effects on the gut 
• CDED + PEN and EEN were equally effective in inducing remission, and when compared to EEN after induction, CDED + PEN produced a better, prolonged remission, indicating a more durable response 
• Children and their parents have shown greater tolerance with CDED + PEN, solving the EEN compliance issues.
• CDED + PEN were associated with sustained microbiome changes compared to EEN^2,5

CD-TREAT 

• CD-TREAT is a whole-food diet designed to chemically mimic the composition of EEN by matching carbohydrates and proteins while excluding gluten and lactose 
• It induced a clinical response in 80% and clinical remission in 60% of pediatric patients with relapsing CD
• It is comparable to EEN in terms of microbiome changes^2,5

Practical considerations for EEN implementation

Close monitoring is required by the healthcare team after starting EEN to observe if there are any adverse effects such as nausea, diarrhoea, constipation, abdominal pain, bloating, and taste fatigue. Another concern is refeeding syndrome in patients who have moderate to severe malnutrition; this uncommon but potentially deadly metabolic consequence is most noticeable. Identifying high-risk individuals and starting enteral feeding gradually while closely monitoring electrolytes are necessary for practical implementation.^1,3

Ensuring compliance and adherence to the protocol is important for a successful induction; however, a standardised universal protocol may be required because EEN protocols vary significantly between countries and healthcare facilities in terms of permitted oral intake, formula type, and duration.³

Future directions and research

Further research is necessary before alternative diets such as the Crohn's Disease Exclusion Diet (CDED) and the CD Treatment with Eating Diet (CD-TREAT) can be suggested for routine clinical practice.² To ensure long-term mucosal healing and remission in paediatric CD, research is required to concentrate on maintaining a healthy microbiota following EEN cessation. Protective microbiome signatures are not the same for all patients or therapeutic interventions, but rather vary from person to person. This highlights the individualised nature of the disease and response to diet, indicating the need for highly personalised management strategies.⁶

FAQs

How effective is EEN compared to corticosteroids?

EEN is equally effective as corticosteroids for overall clinical remission rates for paediatric CD; however, EEN has been shown to be superior in recovery and general health. EEN promotes early mucosal healing, which is linked to better long-term results, including lower hospitalisation rates. There is a faster decline in the Paediatric Crohn's Disease Activity Index (PCDAI) compared to corticosteroids. It actively supports growth at a crucial developmental stage by encouraging increased weight gain and enhancing nutritional status, bone health, bone metabolism, and muscle mass. Growth retardation and decreased bone accretion are two negative side effects of corticosteroids that EEN avoids.^1,2,5

Summary

Crohn’s disease (CD) is a chronic inflammatory bowel disease that frequently begins in childhood, affecting growth, nutrition, and development. Exclusive enteral nutrition (EEN), a liquid formula diet administered for six to eight weeks, is the first-line dietary therapy for inducing remission in pediatric CD. EEN reduces gut inflammation, restores intestinal barrier function, and modifies the microbiota while providing complete nutrition. Clinical remission is achieved in 75-85% of children, with fewer side effects than corticosteroids, avoiding growth suppression and sustained bone mass.

Polymeric formulas are most commonly used due to better taste and lower cost, though efficacy is similar across formula types. Major limitations include poor adherence due to taste, cost, and the strict exclusion of solid food. Alternatives such as partial enteral nutrition (PEN), often combined with the Crohn’s Disease Exclusion Diet (CDED) and alternative methods such as CD Treatment with Eating Diet (CD-TREAT), show promise for better long-term adherence. Future research aims to personalise dietary therapy for individual patients and sustain remission.