We know that the color of urine should be kept in a range of yellowmore or less whitish, and until then everything is going well. Its pigmentation is closely related to the amount of water ingested.however, foods, medications and more or less serious kidney disorders They can dye it occasionally. But if the cause is this hereditary disease, it will be chronically obscured.
Although it may be surprising, various factors can turn habitual pigmentation into red, blue, green, orange or opaque white. In most cases this is explained by urinary tract infections or by kidney stonesalthough there are less important factors such as medications or the consumption of vitamins.
And the urine too can be completely blackthis being a characteristic symptom of alkaptonuria, a rare inherited disease characterized by a metabolic disorder. Specifically, the HDG gene mutates and this causes deficiency of an enzyme found mainly in the liver and kidneyswhich in turn causes homogentisic acid (HGA) to accumulate and stain the urine black.
May be asymptomatic in the first years
Unless it manifests itself in babies, this rare disease can be asymptomatic in the early years and in youth. In adulthood, the dark pigmentation that will appear in the urine can also manifest itself in the white part of the eye, sweat, or the upper cartilage of the ear (ochronosis). Currently, it is estimated that alkaptonuria affects around 250,000 people worldwide.
As for treatment, it is fundamentally palliative and aimed at the patient’s possible ailments because, today, there is no effective treatment that can solve the aforementioned metabolic alteration. A low protein diet and physical exercise They are among the few therapeutic options for affected people.
The CSIC discovered the causative gene
In 1996, the gene causing this hereditary disease was discovered. by a team from the Higher Council for Scientific Research (CSIC), led by Santiago Rodríguez de Córdoba and Miguel Ángel Peñalva. Cover of the prestigious scientific magazine Nature Genetics, assumed the first complete sequencing of a human gene which took place in Spain.
But the disorder already It had been discovered almost a century earlier by the English physician Archibald Garrodwho strove to demonstrate not only that it was hereditary but that the origin was found in the malfunction of an enzyme, as they actually confirmed at the CSIC several decades later.
References
CSIC (September 21, 2021). The CSIC celebrates 25 years since the discovery of the gene for black urine disease, the first genetic disorder described. https://www.csic.es/es/actualidad-del-csic/el-csic-celebra-los-25-anos-del-hallazgo-del-gen-de-la-enfermedad-de-la-orina- black-the-first-genetic-disorder-described