What Is Mulibrey Nanism?
Mulibrey Nanism is an extremely rare genetic pathological condition which is characterized by significant growth delays and significant abnormalities of the muscles, liver, brain, and eyes. The term MULIBREY stands for Muscles, Liver, Brain, and Eye. Children with Mulibrey Nanism also have a condition called constricted pericarditis which results in restriction of normal filling of the heart. Mulibrey Nanism follows an autosomal recessive pattern of inheritance meaning that two copies of the defective gene one from each parent is required for a child to develop Mulibrey Nanism.
The primary presenting feature of Mulibrey Nanism is dwarfism along with extremely low birth weight, significant growth delays, underdevelopment of muscles, and hypotonia. Hepatomegaly is another characteristic feature of Mulibrey Nanism. Additionally, there may be yellow discoloration of the eyes in children with Mulibrey Nanism.
What Causes Mulibrey Nanism?
The gene responsible for the development of Mulibrey Nanism is the TRIM37 gene. This gene is located in the 17th chromosome. This condition follows an autosomal recessive pattern of inheritance meaning that one copy of the defective gene from each parent is required for a child to develop Mulibrey Nanism.
What Are The Symptoms Of Mulibrey Nanism?
Progressive growth failure which begins prenatally is the primary presenting feature of Mulibrey Nanism. Children with this condition generally have a low muscle tone.
They also tend to have a triangularly shaped face along with other abnormalities of the head. There is also yellow discoloration of the eyes in children with Mulibrey Nanism.
Such children in most of the cases have an abnormally high pitched voice. Infants with this condition have symptoms related to overgrowth of the fibrous sac which surrounds the heart which is a condition called constricted pericarditis which affects the functioning of the heart.
If this condition is present at birth then the newborn will have bluish discoloration of the lips and the tips of the fingers. Lung congestion and abdominal ascites are other features of Mulibrey Nanism.
Infants with Mulibrey Nanism also tend to exhibit peripheral edema and cardiac hypertrophy. Hepatomegaly is yet another important presenting feature of Mulibrey Nanism.
Children suffering from Mulibrey Nanism also have increased pressure in the pulmonary artery along with chronic congestion or even blockage of this artery which affects the normal functioning of the lungs. Pulmonary fibrosis may also be present in some cases of Mulibrey Nanism.
Children with Mulibrey Nanism also have underdeveloped endocrine glands which lead to various hormonal problems. Females with this condition tend to have delayed puberty and irregular menstrual periods. There is also an increased risk for premature ovarian failure or ovarian tumors in females with Mulibrey Nanism.
How Is Mulibrey Nanism Diagnosed?
The characteristic features of Mulibrey Nanism make it easier for a physician to diagnose this condition at birth by way of a thorough clinical evaluation. Radiological studies in the form of CT and MRI scans of the heart and the abdominal areas may reveal findings that are characteristic for Mulibrey Nanism like hepatomegaly and constricted pericarditis.
Echocardiograms may further prove the presence of constricted pericarditis. Once Mulibrey Nanism is suspected then a molecular testing may be conducted which will clearly show mutations in gene TRIM37 which will confirm the diagnosis of Mulibrey Nanism.
How Is Mulibrey Nanism Treated?
There is no specific treatment for Mulibrey Nanism. Treatment is only symptomatic and supportive. For conditions like constricted pericarditis surgery may be required to correct the abnormality. For cases of progressive heart failure, medications like diuretics may be given to control the condition.
For children, growth hormone deficiency hormone replacement therapy is recommended. This can also address the issue of delayed puberty and menstrual problems in females with Mulibrey Nanism.
It is highly recommended that females with Mulibrey Nanism should be monitored closely for any signs of ovarian tumor, and if present, prompt treatment should be given. Other than this, only symptomatic and supportive treatment is available for Mulibrey Nanism.
