Conorenal Syndrome or Mainzer-Saldino Syndrome is a group of diseases involving kidney, skeletal system and eye. In few cases, cerebral ataxia has been documented. The skeletal effect indicates cone shape epiphysis of extremity bones. Kidney effects are observed in childhood and eventually results in kidney failure. Retinal pigmentosa results in blindness. The medical condition is a genetic pathological condition which usually affects following organs-
- Kidneys1
- Eyes2
- Skeletal system.
In this article, we will discuss about various symptoms, the genes involved and treatments rendered for Conorenal Syndrome/Mainzer-Saldino Syndrome.
What Is Conorenal Syndrome Or Mainzer-Saldino Syndrome?
Kidney Disease1–
- History of chronic kidney disease.
- Kidney disease often starts during childhood.
- Kidney disease progressively gets worse. The rate with which the renal dysfunction deteriorates is quite variable and differs from person to person, but ultimately the affected individual ends up with renal failure.
Eye Involvement2–
- Conorenal syndrome affects retinal tissue of both the eyes.
- The disease causes degeneration of photosensitive tissue of the retina.
- The intensity and extend of degeneration is variable. Some of the affected people get blind and/or have very poor vision since infancy.
Skeletal Abnormalities-
- The skeletal abnormality seen with Conorenal Syndrome or Mainzer-Saldino Syndrome is one in which the ends of the bone become cone shaped in the fingers.
- The abnormalities are easily identified on x-ray images within the first year of life.
- Bone abnormalities are often observed in multiple bones.
- The growth of the extremity bone is restricted and skeletal abnormalities result in short stature.
- Conorenal Syndrome or Mainzer-Saldino syndrome resulting in short stature is also known as craniosynostosis when shape of the skull and head is abnormal.
Causes of Conorenal Syndrome or Mainzer-Saldino Syndrome
- Genetic Mutation- Conorenal Syndrome / Mainzer-Saldino Syndrome is caused by mutations in IFT140 gene.
- Normal Function of the Gene- The gene IFT140 gives instructions for production of a protein, which is involved in the formation and maintenance of cilia.3
- Function of Cilia-
- Cilia is responsible for transmitting information within the cells and also between cells.3
- Cilia are an extremely important structure for adequate functioning of many cells in the kidneys, liver, and brain.
- The photoreceptors in retina are regulated by cilia. Abnormal function of cilia causes abnormal retinal changes resulting in photosensitivity.
- Although still under research, Cilia is also said to play a role in the development of bones.
Symptoms of Conorenal Syndrome or Mainzer-Saldino Syndrome
Renal Failure-
- Hematuria
- Proteinuria
- Restricted Urine Output
- Hyperkalemia Causing Cardiac Arrhythmia
Skeletal System-
- Cone-shaped bones in fingers
- Cone-shaped bones in toes
- Short stature
Eyes-
- Pigment dystrophy in the cornea
- Loss of night vision which can be progressive
- Loss of peripheral vision
Diagnosis for Conorenal Syndrome Or Mainzer-Saldino Syndrome
Urine Examination-
- Blood in urine
- Proteinuria
- Low urine volume
- Urinary Tract Infection
Blood Examination
- Low Hemoglobin
- Low Red Blood Cell Count
- Increased BUN and Creatinine
Eye Examination
- Abnormal Vision
- Abnormal Retina
- Retinal Detachment
X-Ray Examination-
- X-rays of the fingers and toes shows cone shaped deformity in the bones which is also a symptom of Conorenal Syndrome or Mainzer-Saldino Syndrome.
- Abnormal skeletal alignment in face and skull
Treatment for Conorenal Syndrome Or Mainzer-Saldino Syndrome
Since this syndrome is extremely rare, the specific treatment for this condition is still under research, although individuals with renal failure need dialysis or kidney transplantation.
Symptomatic Therapy Includes-
- Anemia– Iron Pills
- Hyperkalemia- Calcium (either gluconate or chloride)
- Kidney Infection– antibiotics
- Kidney Failure- dialysis
- Eye examination- treated with the vision glasses
- Hereditary sclerosing glomerulopathy in the conorenal syndrome.
Mendley SR1, Poznanski AK, Spargo BH, Langman CB.
Am J Kidney Dis. 1995 May;25(5):792-7. - Saldino-Mainzer syndrome: nephronophthisis, retinitis pigmentosa, and cone-shaped epiphyses.
Mortellaro C1, Bello L, Pucci A, Lucchina AG, Migliario M.
J Craniofac Surg. 2010 Sep;21(5):1554-6. doi: 10.1097/SCS.0b013e3181ec69bb. - Mainzer-Saldino syndrome is a ciliopathy caused by IFT140 mutations.
Perrault I1, Saunier S, Hanein S, Filhol E, Bizet AA, Collins F, Salih MA, Gerber S, Delphin N, Bigot K, Orssaud C, Silva E, Baudouin V, Oud MM, Shannon N, Le Merrer M, Roche O, Pietrement C, Goumid J,
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