Dr. Michael Schumann opened the session with a systematic approach to malabsorption, emphasizing the importance of understanding the distinct phases of nutrient absorption in the small intestine. He outlined the differentiation between malabsorption and maldigestion, noting that while maldigestion is often due to impaired enzymatic activity, malabsorption typically results from structural damage to the intestinal mucosa.
Malabsorption can present with a variety of symptoms, including diarrhea, weight loss, steatorrhea, and deficiencies in fat-soluble vitamins (A, D, E, K) or minerals such as iron and zinc. A practical approach involves starting with basic blood tests to identify deficiencies. Tests for iron, albumin, magnesium, and fat-soluble vitamins are particularly useful as they are commonly affected in malabsorption.
Stool tests remain important but are underused in some clinical settings, particularly in countries like Germany, where technical challenges have led to a decline in their routine application. Dr. Schumann emphasized the value of fecal fat tests, which, although declining in use, can still be critical in identifying steatorrhea in malabsorption syndromes.
A crucial diagnostic tool is the assessment of body composition. Methods such as bioimpedance analysis (BIA) or DEXA are valuable in estimating fat-free mass, which can guide nutritional interventions. These are often overlooked but offer key insights into the patient's metabolic status.
Dr. Annalisa Schiepatti’s presentation focused on the differential diagnosis of refractory enteropathies, with a particular emphasis on refractory celiac disease (RCD). Clinically, RCD should be considered in patients who fail to improve after 12 months of a strict gluten-free diet. Dr. Schiepatti stressed the importance of re-evaluating the initial diagnosis in non-responders, as misdiagnosis of celiac disease is not uncommon.
Dr. Schiepatti highlighted the need for distinguishing between Type 1 and Type 2 RCD. Type 1 RCD generally responds to immunosuppressants, while Type 2 is more aggressive and associated with a higher risk of developing enteropathy-associated T-cell lymphoma (EATL). Clinically, patients with Type 2 RCD require more rigorous monitoring and often benefit from flow cytometry to detect clonal T-cell populations, as well as T-cell receptor gene rearrangement studies.
A practical point for clinicians is the use of flow cytometry, which may not be widespread, but it is a reproducible tool and can help differentiate Type 2 RCD from other seronegative enteropathies. This technology can be integrated into centers specializing in complex cases of refractory enteropathies.
Dr. Christian Lodberg Hvas emphasized the critical role of early and effective nutritional intervention in malabsorptive conditions. Nutritional deficiencies are common and can exacerbate the patient’s condition, leading to longer recovery times and worse outcomes if not promptly addressed.
A key takeaway for clinical practice is the importance of early nutritional support. For patients with severe malabsorption, especially those with significant weight loss or electrolyte imbalances, parenteral nutrition should be considered as a stabilizing intervention while investigating the underlying cause. Dr. Hvas emphasized that oral rehydration solutions (ORS) and parenteral nutrition must often run in parallel with diagnostic evaluations.
Micronutrient deficiencies, such as iron, magnesium, and vitamin B12, are prevalent and should be routinely monitored. Clinicians should be aware that serum magnesium levels may not always reflect deficiency. For instance, patients reporting night cramps may be experiencing magnesium depletion despite normal serum levels. Clinically, Dr. Hvas recommends using oral or intravenous supplementation depending on the severity of the deficiency and patient tolerance.
For iron deficiency, intravenous iron is often preferred for quicker correction, particularly in patients who do not tolerate oral supplementation. Importantly, Dr. Hvas pointed out that fatigue associated with iron deficiency should be addressed even in the absence of anemia, as this can significantly impact the patient's quality of life.
Another practical aspect of management is fluid balance, especially in patients with high-output ostomies or chronic diarrhea. Dr. Hvas highlighted a "Goldilocks zone" for oral fluid intake, where isotonic solutions with appropriate balances of electrolytes are most effective. Overconsumption of water or sugary drinks can exacerbate dehydration by increasing fluid losses through the gut. The optimal solutions are those similar to rehydration salts or milk, which maintain isotonicity and reduce stool output.
Dr. Hvas also recommended that clinicians consider GLP-1 agonists or GLP-2 analogues for patients with high fecal fluid losses or bile acid diarrhea, although the high cost and limited availability of GLP-2 analogues can be a barrier to widespread use.