Causes
Glucose and galactose are two common
sugars, which are present in many foods. They
are found as free sugars, but also in
combination with other sugars (e.g. sucrose –
table sugar – is made up of glucose and
fructose, or lactose – milk sugar – is made up
of glucose and galactose). The malabsorption
and secondary intolerance of glucose and
galactose is due to a genetic abnormality on
chromosome 22 regulating a sugar transporter
protein (SGLT1) and leading to a decreased
ability to absorb the sugars across the lining
(mucosa) of the small intestine.
Frequency in population and natural
history
- Glucose-galactose malabsorption is
rare, with only a few hundred cases
identified worldwide.
- Up to 10% of the population may have a
slightly reduced capacity for glucose
absorption without significant associated
health problems. This condition may be a
milder variation of glucose-galactose
malabsorption.
- Malabsorption and intolerance of
galacto-olicosaccharides as part of a
general FODMAP intolerance is common in
functional bowel syndromes, such as
Irritable Bowel Syndrome (see
Fructose intolerance).
- Both parents of the affected individual
will be carriers of the genetic defect, but
without symptoms (autosomal recessive
condition)
Symptoms
Glucose-galactose malabsorption commonly
becomes apparent in the first weeks of a
baby's life. Typical symptoms are severe
diarrhea leading to life-threatening
dehydration, destabilization of the acidity of
the blood and tissues (acidosis), stomach
cramps, bloating, excess gas production,
vomiting, and weight loss when fed breast milk
or regular infant formulas. They can, however,
digest fructose-based formulas that do not
contain glucose or galactose. As they get
older the affected children often tolerate
glucose and galactose better.
Kidney stones or more calcium deposits in
the kidneys are more frequent, as the genetic
disorder can also affect the kidneys.
Testing and diagnosis
Genetic analysis is the most accurate test.
Breath testing can also be performed. See
Tests.
Management
Avoid ingestion of glucose and galactose,
as well as sugars containing them (e.g.
lactose and sucrose). This means avoiding
table and milk sugar in all forms, such as
sugar cane and sugar beets, sorghum,
confectioners' sugar or powdered sugar, rock
candy, brown sugar (made of white sugar and
molasses), cotton candy, maple syrup, Demerara
and Barbados sugar, molasses, pancake syrup,
gingerbreads, baked beans and pumpernickel
breads, as well as dairy products. Expert
dietary advice is required to implement this
complicated dietary regime.
For glucose content of food see:
http://www.foodstandards.gov.au/consumerinformation/nuttab2010/nuttab2010onlinesearchabledatabase/onlineversion.cfm?&action=nutrientFoods&category=Proximates&nutrientID=GLUC
For galactose content of food see:
http://www.foodstandards.gov.au/consumerinformation/nuttab2010/nuttab2010onlinesearchabledatabase/onlineversion.cfm?&action=nutrientFoods&category=Proximates&nutrientID=GAL
Galactosemia / Galactosaemia
Hereditary galactosemia is a genetic
disease resulting in a deficiency of the
enzyme galactose-1-phosphate uridyltransferase
(GALT). Acute manifestations occur in the
neonatal period. Symptoms are related to
lactose (milk sugar) ingestion and include
poor feeding and growth, vomiting, jaundice,
liver disease, increased bleeding, anemia,
kidney disease, cataracts and brain damage.
Long-term changes involve the brain (delayed
language skills, speech defects and learning
problems) and the ovaries (subnormal
functioning) in adolescents.
http://www.galactosaemia.com/galactosaemia/what-is-galactosaemia.html
http://www.galactosemia.com