Question: What is (are) 2-methylbutyryl-CoA dehydrogenase deficiency ?
Answer: 2-methylbutyryl-CoA dehydrogenase deficiency is a metabolic disorder in which individuals lack adequate levels of an enzyme called 2-methylbutyryl-CoA dehydrogenase. This enzyme assists in the processing of a particular amino acid called isoleucine. The inability to process isoleucine correctly leads to the buildup of the amino acid in the body. The buildup can cause a variety of health problems, which vary widely from severe and life-threatening to mild or absent. Signs and symptoms of the disorder can begin a few days after birth or later in childhood. The initial symptoms often include poor feeding, lack of energy, vomiting, and irritability.
Source: GARD

Question: What are the symptoms of 2-methylbutyryl-CoA dehydrogenase deficiency ?
Answer: What are the signs and symptoms of 2-methylbutyryl-CoA dehydrogenase deficiency? The Human Phenotype Ontology provides the following list of signs and symptoms for 2-methylbutyryl-CoA dehydrogenase deficiency. 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) Apneic episodes in infancy - Autosomal recessive inheritance - Exotropia - Generalized amyotrophy - Hypoglycemia - Hypothermia - Infantile onset - Lethargy - Microcephaly - Motor delay - Muscular hypotonia - Seizures - 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.
Source: GARD