What are the signs and symptoms of Mulibrey Nanism? Mulibrey nanism (MN) is characterized by progressive growth failure that begins prenatally (before birth). Hypotonia (poor muscle tone) is common. Newborns often have characteristic abnormalities of the head and face, including a triangularly shaped face. Yellow discoloration of the eyes and other ocular abnormalities may be present, but vision is usually normal. More than 90 percent of affected individuals have a J-shaped sella turcica, which is a depression in the sphenoid bone at the base of the skull. Infants with mulibrey nanism may also have symptoms related to overgrowth of the fibrous sac surrounding the heart (constrictive pericarditis). When constrictive pericarditis is present at birth, affected infants may have a bluish discoloration of the skin (cyanosis), especially on the lips and fingertips. Individuals with MN typically have a high-pitched voice. Other symptoms may include abnormally prominent veins in the neck, congestion in the lungs, abnormal fluid accumulation in the abdomen (ascites), swelling of the arms and/or legs (peripheral edema), and/or enlargement of the heart (cardiac hypertrophy) and/or liver (hepatomegaly). There may also be elevated pressure in the veins, congestion or blockage in the main artery serving the lungs (pulmonary artery), and/or a build-up of fibrous tissue in the walls of the lungs (pulmonary fibrosis). Associated complications of these conditions may lead to congestive heart failure. In some cases, individuals with mulibrey nanism may have additional physical abnormalities, such as an unusually thin shinbone (fibrous tibia dysplasia). Large cerebral ventricles in the brain and delayed motor development are uncommon findings. Most affected individuals have normal intelligence. Individuals with mulibrey nanism often have underdevelopment of various endocrine glands, that leads to hormone deficiencies. Delayed puberty sometimes occurs, accompanied by infrequent or very light menstrual periods. Females have an increased risk for premature ovarian failure and ovarian tumors. The Human Phenotype Ontology provides the following list of signs and symptoms for Mulibrey Nanism. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Decreased body weight 90% Intrauterine growth retardation 90% Macrocephaly 90% Short stature 90% Hepatomegaly 50% Wide nasal bridge 50% Absent frontal sinuses - Astigmatism - Autosomal recessive inheritance - Congestive heart failure - Dental crowding - Depressed nasal bridge - Dolichocephaly - Dysarthria - Frontal bossing - High pitched voice - Hypertelorism - Hypodontia - Hypoplastic frontal sinuses - J-shaped sella turcica - Microglossia - Muscular hypotonia - Myocardial fibrosis - Nephroblastoma (Wilms tumor) - Nevus - Pericardial constriction - Pigmentary retinopathy - Strabismus - Triangular face - Ventriculomegaly - Weak voice - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.