Alkaptonuria, also known as black urine disease or black bone disease, is a rare inherited genetic disorder caused by a specific mutation in the HGD gene. Due to this disease, the body loses its capacity of processing amino acids phenylalanine and tyrosine. Alkaptonuria is asymptomatic in children or young adults. But the colour of their urine changes to brown or ink-black upon exposure to air. Other symptoms include pigmentation in the ear cartilage and sclera. In adults, pain in weight bearing joints of spine, hip and knee. Severe joint pains often require joint replacement. As the disease progresses, valvular heart disease may occur.
HOW IS ALKAPTONURIA DIAGNOSED?
The diagnosis done to detect this disorder are through tests which include chromatography, DNA testing to check mutated gene, details of family history, physical examination of eye and skin pigmentation, pain in joints and heart and development of stones in organs.
HOW IS ALKAPTONURIA TREATED?
Alkaptonuria may be difficult to treat, however, keeping patient in low protein diet, high amount of vitamin C or ascorbic acid can help. Doctors may prescribe anti-inflammatory drugs, narcotics, physical therapy etc. In extreme cases knee or hip replacement for joint pains may be required.
DID YOU KNOW?
Alkaptonuria has other names: • Alkaptonuria • Homogentisic acid oxidase deficiency • Homogentisic aciduria • Black bone disease • Black urine disease. Most of the people with alkaptonuria live normal lives. In many cases the symptoms are not present till the age of 40’s.