Cystinuria

7 mins read

Cystinuria is genetic disorder which results in the formation of stones in the kidneys, urethra the urinary bladder and in some cases, the intestines. The stones are made of amino acids, majorly Cystine. This is a condition that is inherited and is an autosomal recessive disease. This means, the defective gene must be present and carried on from both the parents.

Causes

  1. The mutations in SLC3A1 and SLC7A9 genes leads to Cystinuria.
  2. The disease is attributed to a defect in the transport of the amino acids and their metabolism.
  3. These defective genes cause the prevention of reabsorption of positively charged Amino Acids like cystine.
  4. This leads to higher concentration of cystine in the urine.
  5. When the level of cystine in the urine increases gradually, the concentration of cystine leads to the formation of kidney stones.

Types Of Cystinuria
Cystinuria is classified into mainly three types.

  • Type I Cystinuria: A defect in the amino acid transport mechanism in both kidneys and small intestine is present in Type I Cystinuria.
  • Type II Cystinuria: In Type II Cystinuria, the transport mechanism is severely weakened in the kidneys and relatively lesser impairment in the small intestine.
  • Type III Cystinuria: In the Type III Cystinuria, the amino acid transport mechanism is weakened in the kidneys, but the function in the small intestine is normal.

Symptoms Of Cystinuria
Cystinuria presents with the following symptoms in most cases

  1. Renal Colic
    • A spasm like pain in the abdominal and groin area, moving from front to back is a typical presentation of Renal Colic. Patients with kidney stones present with renal colic.
    • Other kinds of kidney stones usually take a very long time to form, but stones formed due to Cystinuria can present at a young age.
    • In patients who suffer from Cystinuria, Renal colic pain presents at a younger age, indicating Cystinuria.
  2. Chronic Pain
    • Patients suffering from Cystinuria also present with chronic back and abdominal pain.
    • This can be a dull throb in the area in which the kidneys are present.
    • This kind of pain wears a person down and is felt continually.
  3. Hematuria
    • This is a condition in which Red Blood Cells (RBCs) are present in the urine.
    • This occurs due to the sharp edges of the crystal-like stones leaving scars and damaging organs in the excretory system.
  4. Hydronephrosis
    • This is a condition in which the stones formed in the kidneys block the proper passage of urine and allows accumulation of fluid in the kidney.
    • The kidney may become enlarged causing life threatening kidney complications.

Diagnosis Of Cystinuria

  • Since stones formed by Cystinuria do not show up on imaging studies such as x-ray, CT an MRI scans, it will often be tough to spot the cystine stones. This is the reason Cystinuria can be tough to diagnose.
  • However the imaging study known as Intravenous Pyelogram can be used to visualize cystine stones.
  • A 24 hour urine sample is collected and tested for the levels of cystine in the urine and also to determine the presence of cystine crystals. A cyanide-nitroprusside test is the most definitive.

Treatment Of Cystinuria
The major goal of Cystinuria treatment is to relive pain and to prevent formation of more such stones. Since the patients with Cystinuria suffer from chronic pain, it leads to severe debilitation and sometimes may lead to depression.

  • Pain Relievers are prescribed for reduction and management of pain.
  • Patients suffering from Cystinuria are asked to increase their fluid intake.
  • Initially the patient is asked to reduce their salt and protein intake.
  • Medicines that dissolve cystine crystals are administered.
  • If the above treatments do not show improvement in conditions, chelation therapy is done.
  • If the stones have formed, extracorporeal shock wave lithotripsy (ESWL) is done to try and breakup the stones.
  • ESWL usually shows lesser effectiveness as the cystine crystals are much harder.
  • If ESWL fails, then a surgery is performed to remove the cystine stones. However, this is the last line of treatment unless there is an emergency condition.

Preventive Measures

  • Drink lots of water to produce lots of urine. This will help to reduce the concentration of cystine in the urine.
  • This high quantity of urine produced will also help to pass the stones quickly.
  • Since the stones might form again even after a surgery, one must get regular checkups and screenings to monitor the formation and passage of stones.

Conclusion: Patients may become depressed due to chronic pain and related complications, but necessary treatment and counseling by a qualified medical professional will help overcome such depression. Cystinuria might not have a cure, but with proper pain management and appropriate treatment, one can life a comfortable and pain free life.

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References
1. Janeckova H, Kalivodova A, Najdekr L, Friedecky D, Hron K, Bruheim P, Adam T. Untargeted metabolomic analysis of urine samples in the diagnosis of some inherited metabolic disorders. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2014 Nov 7. doi: 10.5507/bp.2014.048. [Epub ahead of print] PubMed PMID: 25482736.

2. Sahota A, Parihar JS, Capaccione KM, Yang M, Noll K, Gordon D, Reimer D, Yang I, Buckley BT, Polunas M, Reuhl KR, Lewis MR, Ward MD, Goldfarb DS, Tischfield JA. Novel Cystine Ester Mimics for the Treatment of Cystinuria-induced Urolithiasis in a Knockout Mouse Model. Urology. 2014 Nov;84(5):1249.e9-1249.e15. doi: 10.1016/j.urology.2014.07.043. Epub 2014 Oct 24. PubMed PMID: 25443947.

3. Fattah H, Hambaroush Y, Goldfarb DS. Cystine nephrolithiasis. Transl Androl Urol. 2014 Sep 1;3(3):228-233. PubMed PMID: 25383320; PubMed Central PMCID: PMC4220544.

4. Bourderioux M, Nguyen-Khoa T, Chhuon C, Jeanson L, Tondelier D, Walczak M,Ollero M, Bekri S, Knebelmann B, Escudier E, Escudier B, Edelman A, Guerrera IC.

5. A New Workflow for Proteomic Analysis of Urinary Exosomes and Assessment in Cystinuria Patients. J Proteome Res. 2014 Nov 12. [Epub ahead of print] PubMed PMID: 25365230.

6. Ohtsuka Y, Higashimoto K, Sasaki K, Jozaki K, Yoshinaga H, Okamoto N, Takama Y, Kubota A, Nakayama M, Yatsuki H, Nishioka K, Joh K, Mukai T, Yoshiura KI, Soejima H. Autosomal recessive cystinuria caused by genome-wide paternal uniparental isodisomy in a patient with Beckwith-Wiedemann syndrome. Clin Genet. 2014 Aug 29. doi: 10.1111/cge.12496. [Epub ahead of print] PubMed PMID: 25171146.

7. Sfoungaristos S, Hakim R, Katz R, Gofrit ON, Landau EH, Yutkin V, Pode D, Duvdevani M. Cystine Stones: A Single Tertiary Center Experience. J Endourol. 2014 Oct 9. [Epub ahead of print] PubMed PMID: 25133928.

8. Wong KA, Mein R, Wass M, Flinter F, Pardy C, Bultitude M, Thomas K. The Genetic Diversity of Cystinuria in a UK Population of Patients. BJU Int. 2014 Aug 11. doi: 10.1111/bju.12894. [Epub ahead of print] PubMed PMID: 25109415.

9. Shim M, Park HK. Multimodal treatments of cystine stones: an observational, retrospective single-center analysis of 14 cases. Korean J Urol. 2014 Aug;55(8):515-9. doi: 10.4111/kju.2014.55.8.515. Epub 2014 Aug 8. PubMed PMID: 25132945; PubMed Central PMCID: PMC4131079.

10. Thomas K, Wong K, Withington J, Bultitude M, Doherty A. Cystinuria-a urologist’s perspective. Nat Rev Urol. 2014 May;11(5):270-7. doi: 10.1038/nrurol.2014.51. Epub 2014 Mar 25. Review. PubMed PMID: 24662732.

11. Saravakos P, Kokkinou V, Giannatos E. Cystinuria: current diagnosis and management. Urology. 2014 Apr;83(4):693-9. doi: 10.1016/j.urology.2013.10.013. Epub 2013 Nov 16. Review. PubMed PMID: 24246330.

12. Brons AK, Henthorn PS, Raj K, Fitzgerald CA, Liu J, Sewell AC, Giger U. SLC3A1 and SLC7A9 mutations in autosomal recessive or dominant canine cystinuria: a new classification system. J Vet Intern Med. 2013 Nov-Dec;27(6):1400-8. doi: 10.1111/jvim.12176. Epub 2013 Sep 3. PubMed PMID: 24001348; PubMed Central PMCID: PMC3946761.

13. Kummer S, Venghaus A, Schlune A, Leube B, Eggermann T, Spiekerkoetter U. Synergistic mutations in SLC3A1 and SLC7A9 leading to heterogeneous cystinuria phenotypes: pitfalls in the diagnostic workup. Pediatr Nephrol. 2014 Jan;29(1):155-9. doi: 10.1007/s00467-013-2617-2. Epub 2013 Sep 19. PubMed PMID: 24045899.

14. Izol V, Aridogan IA, Karsli O, Deger M, Satar N. The effect of prophylactic treatment with Shohl’s solution in children with cystinuria. J Pediatr Urol. 2013 Dec;9(6 Pt B):1218-22. doi: 10.1016/j.jpurol.2013.05.017. Epub 2013 Jun 24. PubMed PMID: 23806278.

15. Eggermann T, Venghaus A, Zerres K. Cystinuria: an inborn cause of urolithiasis. Orphanet J Rare Dis. 2012 Apr 5;7:19. doi: 10.1186/1750-1172-7-19. Review. PubMed PMID: 22480232; PubMed Central PMCID: PMC3464901.

16. Claes DJ, Jackson E. Cystinuria: mechanisms and management. Pediatr Nephrol. 2012 Nov;27(11):2031-8. doi: 10.1007/s00467-011-2092-6. Epub 2012 Jan 27. Review. PubMed PMID: 22281707.

17. Morales CM. [Cystinuria: diagnosis and therapeutic approach]. An Sist Sanit Navar. 2011 Sep-Dec;34(3):453-61. Review. Spanish. PubMed PMID: 22233848.

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