Type II tyrosinemia
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:
Overview
Overview
Type II tyrosinemia is caused by a deficiency of the enzyme tyrosine aminotransferase (EC 2.6.1.5), encoded by the gene TAT.
Historical Perspective
Historical Perspective
Classification
Classification
Pathophysiology
Pathophysiology
Tyrosine aminotransferase is the first in a series of five enzymes that converts tyrosine to smaller molecules, which are excreted by the kidneys or used in reactions that produce energy. This form of the disorder can affect the eyes, skin, and mental development.
Causes
Causes
Differentiating Type II tyrosinemia from Other Diseases
Differentiating Type II tyrosinemia from Other Diseases
Epidemiology and Demographics
Epidemiology and Demographics
Type II tyrosinemia occurs in fewer than 1 in 250,000 individuals.
Risk Factors
Risk Factors
Screening
Screening
Natural History, Complications, and Prognosis
Natural History, Complications, and Prognosis
Natural History
Complications
Prognosis
Diagnosis
Diagnosis
Diagnostic Criteria
History and Symptoms
Symptoms often begin in early childhood and include excessive tearing, abnormal sensitivity to light (photophobia), eye pain and eye redness, and painful skin lesions on the palms and soles. About half of individuals with type II tyrosinemia are also mentally retarded.
Physical Examination
Laboratory Findings
Imaging Findings
Other Diagnostic Studies
Treatment
Treatment
Medical Therapy
Surgery
Prevention
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