Glucose Galactose Malabsorption (GGM) is a rare disorder caused by a defect in membrane transport in the small bowel mucosa.


Mechanism: mutation in the sodium-glucose transporter gene


Inhteritance: autosomal recessive


Gene: SGLT1

Chromosome: 22q13.1


Clinical features:

(1) The onset of diarrhea soon after birth (neonatal or early infancy).

(2) The stool is watery with an acidic pH.

(3) The diarrhea is dependent on intake of glucose, galactose or lactose and stops within an hour if all 3 sugars are removed from the diet.

(4) A H2 breath test is positive if the patient is exposed to glucose, galactose or lactose.

(5) Absorption of fructose is not impaired.

(6) No other diagnosois can explain the findings better.


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