Lactose deficiency

Testing for lactose deficiency can confirm the presence of lactose intolerance, which may explain the symptoms. 

The carbohydrate analyzer has shown that there are considerable differences in excretion patterns of carbohydrates in disease. Many carbohydrates are excreted in excess in renal glycosuria and diabetes mellitus (Yl). Other abnormalities, such as pancreatic insufiSciency and lactose deficiency, show several carbohydrate excretion abnormalities. The presence of large amounts of xylulose and other sugars during ingestion of xylose indicates that the xylose tolerance test may not be a true measurement of absorption since that sugar apparently also metabolizes (Yl). 

In patients whose maldigestion is difficult to control, other underlying conditions should be considered, such as noncompliance, infections of the gastrointestinal tract, celiac disease, lactose deficiency, inflammatory bowel disease, anatomical abnormalities, diabetes, and liver cirrhosis. This question is complicated by the abundance of small intestinal viscous glycoproteins in cystic fibrosis, prolonged intestinal transit times, which may provoke bacterial overgrowth [104], and absorption of the enzymes in their macromolecular form [105]. 

Digestion of lactose is facilitated by the p glycosidase lactase A deficiency of this enzyme makes it difficult to digest lactose and causes abdominal discomfort Lactose intolerance is a genetic trait it is treatable through over the counter formulations of lac tase and by limiting the amount of milk m the diet... 

Lactose Milk. May occur in urine during pregnancy. In lactase deficiency, malabsorption leads to diarrhea and flatulence. 

Symptoms of lactase deficiency after ingestion of lactose (milk products) include... 

Lactase The disaccharide lactose is the only carbohydrate present in milk, which is essential for survival of an infant. Consequently, the enzyme lactase is essential for babies. Caucasians retain lactase activity into adulthood, whereas many Asian or African groups progressively lose its activity in adult life. This could, therefore, be described as an adult deficiency disease. Ingestion of milk in these individuals causes nausea, diarrhoea and stomach cramps. Symptoms disappear if milk is excluded from the diet or if a source of lactase is ingested along with or before ingestion of milk. The bacteria that are involved in the production of yoghurt contain the enzyme lactase. 

Orotic acid in the diet (usually at a concentration of 1 per cent) can induce a deficiency of adenine and pyridine nucleotides in rat liver (but not in mouse or chick liver). The consequence is to inhibit secretion of lipoprotein into the blood, followed by the depression of plasma lipids, then in the accumulation of triglycerides and cholesterol in the liver (fatty liver) [141 — 161], This effect is not prevented by folic acid, vitamin B12, choline, methionine or inositol [141, 144], but can be prevented or rapidly reversed by the addition of a small amount of adenine to the diets [146, 147, 149, 152, 162]. The action of orotic acid can also be inhibited by calcium lactate in combination with lactose [163]. It was originally believed that the adenine deficiency produced by orotic acid was caused by an inhibition of the reaction of PRPP with glutamine in the de novo purine synthesis, since large amounts of PRPP are utilized for the conversion of orotic acid to uridine-5 -phosphate. However, incorporation studies of glycine-1- C in livers of orotic acid-fed rats revealed that the inhibition is caused rather by a depletion of the PRPP available for reaction with glutamine than by an effect on the condensation itself [160]. 

Galactose intolerance Voriconazole tablets contain lactose and should not be given to patients with rare hereditary problems of galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption. 

The answer is B. This patient s greasy, foul-smelling stools indicate steatorrhea. Her vision problems may be a manifestation of vitamin A deficiency due to fat malabsorption. The most likely explanation is biliary insufficiency, ie, decreased bile salt production leading to poor emulsification of dietary fats. Active ileal disease is a possibility, but the WBC count would likely be elevated unless her condition was in remission. Infection with Giardia is less likely due to the absence of pathogenic organisms in her stool. Lactose intolerance can produce diarrhea but not steatorrhea. 

The real need for lactose-free milk products is hmited as most lactase-deficient adults can tolerate larger amounts than they are likely to consume. 

Figure 4.2.2 depicts the urinary oligosaccharide patterns of sialidosis (a-neur-aminidase deficiency), GM1 gangliosidosis and mucopolysaccharidosis type IVB (/3-galaclosidase deficiency) compared to a normal urine and standards of raffinose, lactose and glucose. In patients with sialidosis, a densely staining band close to the... 

Elevated in deficiencies of galactokinase, galactose-1-phosphate uridyltransferase (classical galactosemia), UDP galactose-4-epimerase, and Fanconi-Bickel-syn drome, portocaval shunt, and cirrhosis, depending on time after lactose consumption. 

There are several forms of intolerance to lactose and galactose. Primary adult lactase deficiency is a normal age-related decrease in lactase activity seen in the majority of adults. Secondary lactase deficiency is a transient state of low enzyme activity following injury to the intestinal mucosa as a result of diseases such as celiac sprue, infectious gastroenteritis, and protein-calorie malnutrition. The last two states are common conditions (Dahlqvist 1983). 

---