Megacystis microcolon intestinal hypoperistalsis syndrome

Información en español Title

Other Names:

MMIH syndrome; Berdon syndrome; MMIHS; MMIH syndrome; Berdon syndrome; MMIHS; Megacystis-microcolon-intestinal hypoperistalsis-hydronephrosis syndrome See More

Categories:

Congenital and Genetic Diseases; Digestive Diseases; Kidney and Urinary Diseases

Summary Summary

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare congenital condition characterized by abdominal distension caused by a largely dilated non-obstructed urinary bladder (megacystis); very small colon (microcolon); and decreased or absent intestinal movements (intestinal peristalsis). Usual clinical presentation is similar to other neonatal intestinal obstructions: bile stained vomiting and failure to pass meconium (the first bowel movement the baby has). Other intestinal anomalies may be present like intestinal malrotation. Many problems with the urinary tract result from the bladder dysfunction. It is part of a group of conditions caused by changes (mutations) in the ACTG2 gene and is inherited in an autosomal dominant manner. However medical scientists believe that many cases of MMIHS are caused by de novo mutations in the ACTG2 gene (meaning the mutation in the gene happened by mistake during the making of the sperm or egg). There is currently no cure for MMIHS and treatment is supportive. In the majority of patients total parenteral nutrition is required.^[1]

Last updated: 10/20/2016

Symptoms Symptoms

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is primarily characterized by abdominal distention caused by an enlarged bladder (megacystis) and intestinal pseudo-obstruction.The enlarged bladder may be detected prenatally.^[2] Children with MMIHS may have various abnormalities of the digestive tract, including microcolon (very small colon), malrotation of the gut, decreased or absent intestinal movements, and short bowel. Additional abnormalities of the urinary tract that have been described include renal dysplasia, hydronephrosis, and enlargement of the ureter. Abnormalities that have been reported in some cases include undescended testes or bilateral streak gonads (underdeveloped gonads), heart anomalies, umbilical hernia, or omphalocele.^[2]

Last updated: 8/10/2017

The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.

Signs and Symptoms	Approximate number of patients (when available)
Abdominal distention	Very frequent (present in 80%-99% of cases)
Hypoperistalsis	Very frequent (present in 80%-99% of cases)
Megacystis	Very frequent (present in 80%-99% of cases)
Microcolon	Very frequent (present in 80%-99% of cases)
Nausea and vomiting	Very frequent (present in 80%-99% of cases)
Hydroureter	Frequent (present in 30%-79% of cases)
Intestinal malrotation	Frequent (present in 30%-79% of cases)
Multicystic kidney dysplasia	Frequent (present in 30%-79% of cases)
Polyhydramnios	Frequent (present in 30%-79% of cases)
Cryptorchidism	Occasional (present in 5%-29% of cases)
Death in infancy	Occasional (present in 5%-29% of cases)
Neoplasm of the heart	Occasional (present in 5%-29% of cases)
Omphalocele	Occasional (present in 5%-29% of cases)
Pancreatitis	Occasional (present in 5%-29% of cases)
Sepsis	Occasional (present in 5%-29% of cases)
Umbilical hernia	Occasional (present in 5%-29% of cases)
Aganglionic megacolon	-
Autosomal dominant inheritance	-
Constipation	-
Diarrhea	-
Dysphagia	-
Hydronephrosis	-
Malnutrition	-
Vesicoureteral reflux	-
Vomiting	-

Last updated: 9/1/2017

Cause Cause

This condition is part of a group of disorders caused by mutations in the ACTG2 gene. ACTG2-related disorders are inherited in an autosomal dominant manner.^[1]

Last updated: 8/19/2015

Inheritance Inheritance

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is inherited in an autosomal dominant manner.^[1] This means that having a change (mutation) in only one copy of the responsible gene in each cell is enough to cause features of the condition. There is nothing that either parent can do, before or during a pregnancy, to cause a child to have this condition.

In some cases, an affected person inherits the mutation from an affected parent. In other cases, the mutation occurs for the first time in a person with no family history of the condition. This is called a de novo mutation. While the exact proportion of inherited versus de novo mutations is unknown, current data suggest that de novo mutations are common.^[1]

When a person with a mutation that causes an autosomal dominant condition has children, each child has a 50% (1 in 2) chance to inherit that mutation. However, the severity of signs and symptoms can vary within a family. If the mutation in a family member with MMIHS has been identified, prenatal testing for pregnancies at increased risk is possible.^[1]

Last updated: 8/10/2017

Diagnosis Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Treatment Treatment

The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.

Management Guidelines

GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.

Prognosis Prognosis

Survival in MMIHS seems to have improved, thanks to more specialized care, innovations in parenteral nutrition, and introduction of multivisceral transplantation.^[2] Long-term survival usually requires total parenteral nutrition and urinary catheterization or diversion. Most long-term survivors have ileostomies.^[1] In families with an inherited MMIHS-causing mutation, some family members with a mutation have milder features, living into adolescence and early adulthood.^[1]

While there are reports of longer survival, the prognosis and life expectancy remains poor, and it is still fatal in many cases. The main causes of death include sepsis, malnutrition, or multiple organ failure.^[2]

Last updated: 8/10/2017

Do you have updated information on this condition? Let us know.

Research Research

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.
The U.S. National Institutes of Health, through the National Library of Medicine, developed ClinicalTrials.gov to provide patients, family members, and members of the public with current information on clinical research studies. There is a study titled Pediatric Patients With Metabolic or Other Genetic Disorders which may be of interest to you. To find this trial, click on the link above.

Organizations Organizations

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Birth Defect Research for Children, Inc.
976 Lake Baldwin Lane, Suite 104
Orlando, FL 32814
Telephone: 407-895-0802
E-mail: staff@birthdefects.org
Website: http://www.birthdefects.org/
MMIHS.org
Website: http://www.mmihs.org/
Parent based organization. Offers several resources.
The Feingold Center for Children
52 Second Avenue, 1st Floor
Suite 520
Waltham, MA 02451
Telephone: 781-466-9555
Fax: 781-487-2361
E-mail: info@thenbdc.org
Website: http://www.thefeingoldcenter.org/

Do you know of an organization? Send us your suggestions.

Living With Living With

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Genetics Resources

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by GeneTests, the American College of Medical Genetics, and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.

Learn More Learn More

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
PubMed is a searchable database of medical literature and lists journal articles that discuss Megacystis microcolon intestinal hypoperistalsis syndrome. Click on the link to view a sample search on this topic.

News & Events News & Events

News

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August 31, 2017
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August 30, 2017
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August 10, 2017

Related Diseases Related Diseases

The following diseases are related to Megacystis microcolon intestinal hypoperistalsis syndrome. If you have a question about any of these diseases, you can contact GARD.

ACTG2-related disorders

GARD Answers GARD Answers

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How long can a person live if they are born with megacystis microcolon intestinal hypoperistalsis syndrome? See answer

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References References

Wangler MF. ACTG2-Related Disorders. GeneReviews. June 11, 2015; http://www.ncbi.nlm.nih.gov/books/NBK299311/.
Puri P. Megacystis-microcolon-intestinal hypoperistalsis syndrome. Orphanet. September, 2012; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=GB&Expert=2241.

Do you know of a review article? Send us your suggestions.