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Disease Profile

Senior Loken Syndrome

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
<1 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Adolescent

ICD-10

Q61.5

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Senior-Loken Syndrome; Renal dysplasia retinal aplasia; Renal-retinal syndrome;

Categories

Congenital and Genetic Diseases; Eye diseases; Kidney and Urinary Diseases

Summary

Senior Loken syndrome (SLS) is a rare syndrome that mainly affects the kidneys and eyes. SLS causes a cystic kidney disease called nephronophthisis, which usually begins in early childhood. The kidneys develop cysts, inflammation, and scarring, which progressively impair kidney function. Symptoms of nephronophthisis may include increased production of urine, excessive thirst, weakness, and severe fatigue. Nephronophthisis typically leads to end-stage kidney disease by adolescence.[1][2][3]

SLS affects the eyes by causing varying degrees of retinal dystrophy, which is progressive wasting of the retina (the part of the eye that senses light and sends images to the brain). Some children with SLS have a severe type of retinal dystrophy at birth called Leber congenital amaurosis (LCA). Symptoms of LCA include severe farsightedness, light sensitivity (photophobia), and nystagmus.[1][3] Other children with SLS do not have LCA but later develop symptoms of a retinal dystrophy called retinitis pigmentosa (RP). Symptoms of RP range in age of onset and severity, and may include night blindness, progressive loss of peripheral vision, and eventual loss of central vision, leading to blindness.[3][4]

In rare cases, additional symptoms such as liver fibrosis or skeletal abnormalities have been reported.[3][5]

SLS may be caused by mutations in any of several genes, and inheritance is autosomal recessive. The syndrome can be diagnosed based on symptoms, kidney and eye evaluations, and genetic testing.[3]

Treatment during earlier stages of kidney disease in children includes maintaining a healthy balance of fluid and electrolytes. End-stage kidney disease requires dialysis, or kidney transplantation. After transplantation, kidney damage does not occur again.[3][6] End-stage kidney disease can be life-threatening if not treated. There is currently no treatment to prevent or stop the progression of vision loss due to retinal dystrophy, but various low-vision aids may be helpful for those who have remaining vision.[3]

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormality of retinal pigmentation
0007703
Global developmental delay
0001263
Hypertension
0000822
Retinal dystrophy
Breakdown of light-sensitive cells in back of eye
0000556
Short stature
Decreased body height
Small stature

[ more ]

0004322
Stage 5 chronic kidney disease
0003774
30%-79% of people have these symptoms
Nephronophthisis
0000090
Premature ovarian insufficiency
Early menopause
Premature menopause
Premature ovarian failure

[ more ]

0008209
Progressive visual loss
Progressive loss of vision
Progressive vision loss
Progressive visual impairment
Slowly progressive visual loss
Vision loss, progressive
Visual loss, progressive

[ more ]

0000529
5%-29% of people have these symptoms
Abnormality of bone mineral density
0004348
Ataxia
0001251
Cataract
Clouding of the lens of the eye
Cloudy lens

[ more ]

0000518
Cone-shaped epiphysis
Cone-shaped end part of bone
0010579
Congenital hepatic fibrosis
Excessive buildup of connective tissue and scarring of liver at birth
0002612
Percent of people who have these symptoms is not available through HPO
Anemia
Low number of red blood cells or hemoglobin
0001903
Autosomal recessive inheritance
0000007
Polydipsia
Extreme thirst
0001959
Polyuria
Increased urine output
0000103
Rod-cone dystrophy
0000510

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • Orphanet lists international laboratories offering diagnostic testing for this condition.

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • MedlinePlus Genetics contains information on Senior Loken Syndrome. This website is maintained by the National Library of Medicine.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Senior Loken Syndrome. Click on the link to view a sample search on this topic.

References

  1. Senior-Løken syndrome. Genetics Home Reference (GHR). June 2012; https://ghr.nlm.nih.gov/condition/senior-loken-syndrome.
  2. Nephronophthisis. Genetics Home Reference. September, 2014; https://ghr.nlm.nih.gov/condition/nephronophthisis.
  3. Senior Løken Syndrome. National Organization for Rare Disorders (NORD). 2016; https://rarediseases.org/rare-diseases/senior-loken-syndrome/.
  4. Ronquillo CC, Bernstein PS, Baehr W. Senior-Løken syndrome: a syndromic form of retinal dystrophy associated with nephronophthisis. Vision Res. December 15, 2012; 75:88-97. https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22819833/.
  5. Qiu L, Mais DD. Clinicopathologic Features of Hepatic Involvement in SeniorLoken Syndrome: A Case Report and Review of Literature. J Liver Clin Res. October, 2017; 4(2):1037. https://www.jscimedcentral.com/Liver/liver-4-1037.pdf.
  6. Niaudet P. Clinical manifestations, diagnosis, and treatment of nephronophthisis. UpToDate. Waltham, MA: UpToDate; September 14, 2017; https://www.uptodate.com/contents/clinical-manifestations-diagnosis-and-treatment-of-nephronophthisis.
  7. Avila A, Ayuso C, Corton M, Millan Salvador JM. Senior-Loken syndrome. Orphanet. December, 2011; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=3156.