RT Book, Section A1 Hill, Ivor D. A1 Caicedo, Ricardo A. A2 Rudolph, Colin D. A2 Rudolph, Abraham M. A2 Lister, George E. A2 First, Lewis R. A2 Gershon, Anne A. SR Print(0) ID 7037058 T1 Chapter 408. Disorders of Digestion and Absorption T2 Rudolph's Pediatrics, 22e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-149723-7 LK accesspediatrics.mhmedical.com/content.aspx?aid=7037058 RD 2024/11/02 AB The assimilation of ingested nutrients involves a complex integrated process of digestion and absorption with subsequent transport of the breakdown products across the intestinal mucosa into the systemic circulation. Normal digestion and absorption is discussed in Chapter 381. The term malabsorption is broadly used to characterize abnormalities of both digestion and absorption. The schema in Table 408-1 lists the major pathogenic mechanisms of various specific malabsorptive disorders that are generally due to disorders in luminal digestion, mucosal function, or lymphatic transport. Malabsorption may involve multiple nutrients (as occurs with celiac disease or pancreatic insufficiency) or only a single molecule (as found in isolated glucose-galactose malabsorption or vitamin B12 malabsorption). Defects may be congenital, with onset of symptoms shortly after birth, or acquired, when the age of onset of symptoms is variable.