Trichohepatoenteric syndrome
What is trichohepatoenteric syndrome?
Trichohepatoenteric syndrome is a condition that affects the hair (tricho-), liver (hepato-), and intestines (enteric), as well as other tissues and organs in the body. This condition is also known as syndromic diarrhea because chronic, difficult-to-treat diarrhea is one of its major features. Within the first few weeks of life, affected infants develop watery diarrhea that occurs multiple times per day. Even with nutritional support through intravenous feedings (parenteral nutrition), many of these children experience failure to thrive, which means they do not gain weight or grow at the expected rate. Most children with trichohepatoenteric syndrome are small at birth, and they remain shorter than their peers throughout life.
Abnormal hair is another feature of trichohepatoenteric syndrome. Hair in affected individuals is described as wooly, brittle, patchy, and easily pulled out. Under a microscope, some strands of hair can be seen to vary in diameter, with thicker and thinner spots. This feature is known as trichorrhexis nodosa.
Other signs and symptoms of trichohepatoenteric syndrome can include liver disease; skin abnormalities; and distinctive facial features, including a wide forehead, a broad base of the nose, and widely spaced eyes. Overall, the facial features are described as "coarse." Most affected individuals also experience immune system abnormalities that can make them prone to developing infections. Less commonly, trichohepatoenteric syndrome is associated with heart (cardiac) abnormalities. Mild intellectual disability has been reported in at least half of all children with the condition.
Trichohepatoenteric syndrome is often life-threatening in childhood, particularly in children who develop liver disease or severe infections.
How common is trichohepatoenteric syndrome?
Trichohepatoenteric syndrome is a rare condition with an estimated prevalence of about 1 in 1 million people. At least 44 cases have been reported in the medical literature.
What genes are related to trichohepatoenteric syndrome?
Trichohepatoenteric syndrome can be caused by mutations in the TTC37 or SKIV2L gene. These genes provide instructions for making proteins whose functions have not been confirmed. Researchers speculate that they work together with other proteins within cells to help recognize and break down excess or abnormal messenger RNA (mRNA) molecules. mRNA is a chemical cousin of DNA that serves as the genetic blueprint for protein production. Studies suggest that getting rid of excess and abnormal mRNA is important for cell growth.
Mutations in the TTC37 or SKIV2L gene likely eliminate the function of their respective proteins, which is hypothesized to impair the breakdown of unneeded mRNA. However, it is unknown how these changes could lead to chronic diarrhea and the other features of trichohepatoenteric syndrome.
How do people inherit trichohepatoenteric syndrome?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
Where can I find information about diagnosis or management of trichohepatoenteric syndrome?
These resources address the diagnosis or management of trichohepatoenteric syndrome and may include treatment providers.
- American Society for Parenteral and Enteral Nutrition: What is Parenteral
Nutrition? - Genetic Testing Registry: Trichohepatoenteric
syndrome - Genetic Testing Registry: Trichohepatoenteric syndrome
2 - MedlinePlus Health Topic: Nutritional
Support
You might also find information on the diagnosis or management of trichohepatoenteric syndrome inEducational resources and Patient support.
General information about the diagnosis and management of genetic conditions is available in the Handbook. Read more about genetic testing, particularly the difference between clinical tests and research tests.
To locate a healthcare provider, see How can I find a genetics professional in my area? in the Handbook.
Where can I find additional information about trichohepatoenteric syndrome?
You may find the following resources about trichohepatoenteric syndrome helpful. These materials are written for the general public.
- MedlinePlus - Health information (4 links)
- Educational resources - Information pages (5 links)
- Patient support - For patients and families (4 links)
You may also be interested in these resources, which are designed for healthcare professionals and researchers.
- Genetic Testing Registry - Repository of genetic test information (2 links)
PubMed - Recent literature- OMIM - Genetic disorder catalog (2 links)
What other names do people use for trichohepatoenteric syndrome?
- diarrhea, fatal infantile, with trichorrhexis nodosa
- diarrhea, syndromic
- intractable diarrhea with phenotypic anomalies
- phenotypic diarrhea of infancy
- SD/THE
- syndromic diarrhea
- THES
- THE syndrome
- tricho-hepato-enteric syndrome
For more information about naming genetic conditions, see the Genetics Home Reference Condition Naming Guidelines and How are genetic conditions and genes named? in the Handbook.
What if I still have specific questions about trichohepatoenteric syndrome?
Where can I find general information about genetic conditions?
The Handbook provides basic information about genetics in clear language.
- What does it mean if a disorder seems to run in my family?
- What are the different ways in which a genetic condition can be inherited?
- If a genetic disorder runs in my family, what are the chances that my children will have the condition?
- Why are some genetic conditions more common in particular ethnic groups?
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding trichohepatoenteric syndrome?
autosomal ; autosomal recessive ; cardiac ; cell ; chronic ; diameter ; DNA ; enteric ; failure to thrive ;gene ; immune system ; messenger RNA ; mRNA ; prevalence ; protein ; recessive ; RNA ; syndrome
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (7 links)
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.
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