Cystinuria is a rare congenital disease (one case per 7000 people). It is caused by the excess of cystine in the urine, which triggers the formation of stones in kidneys, urethra and bladder, as well as pain in the affected areas.
Among the current methods for diagnosis, the most common is the collection of samples for microscopic examination to confirm the presence of stones. The disadvantage is that diagnostic is obtained only after the disease has progressed and the stones are already formed. Also, false positives can occur as the stones could be caused by other reasons.
Another current method is the cyanide-nitroprusside test, which detects cystine excretion but it is not specific enough as it can result in false positives due to drugs -such as when patients are receiving a treatment of N-acetilcisteine, a usual mucolytic. More sophisticated methods are genetic tests, which enable an early diagnosis, but they are much more expensive.
Cystinuria is caused by the excess of cystine in the urine, which triggers the formation of stones in kidneys, urethra and bladder, as well as pain in the affected areas.
A scientific team at the CSIC’s Institut de Química Avanzada de Cataluña (IQAC-CSIC) has developed a system for the early diagnosis of cystinuria. The technology, which has been patented, can enable the development of a cheap and reliable diagnostic essay.
The test is based on a mixture of substances which react in a certain way when they enter in contact with cystine or cysteine: in the presence of any of these molecules, the molecular system generates a blue fluorescence.
The scientists have assessed the essay with samples of human urine. The outcome is obtained in near an hour, which demonstrates the potential of the essay as a diagnosis tool. The scientists have published the result in the magazine Angewandte Chemie.
Useful for other diseases and areas
The study is a ‘proof of concept’ that demonstrates the potential of this technology based on molecular networks for medical diagnosis and detection of specific molecules.
Ignacio Alfonso, a CSIC scientists in the IQAC and the leader of the project, explains:”we think the method can be applied to other systems and molecules. The idea is to create dynamic systems that combine and adapt in a different way depending on the stimulus they receive, such as a specific substance.”
It is, says Ignacio Alfonso, “like a puzzle, whose parts are known as well as the way they will assemble when entering in contact with something. If we know how this molecular network will react, it can be designed to give a specific reaction to a specific molecule”.
The study is based on a previous study, where scientists demonstrated the potential of molecular systems interactions and their adaptation to the environment, and which appeared on the cover of the Chemistry European Journal.
Reference articles:
Maria Lafuente, Jordi Solà and Ignacio Alfonso. A dynamic chemical network for cystinuria diagnosis. Angewandte Chemie Int. Ed. DOI: 10.1002/anie.201802189
Angel M. Valdivielso, Francesc Puig-Castellví, Joan Atcher, Jordi Solà, Romà Tauler and Ignacio Alfonso. Unraveling the multistimuli responses of a complex dynamic system of pseudopeptidic macrocycles. Chemistry European Journal.