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Abstract: SA-PO812

A Case Report of Functional Renal Impairment in Adult Patient with Townes-Brocks Syndrome

Session Information

Category: Genetic Diseases of the Kidneys

  • 1202 Genetic Diseases of the Kidneys: Non-Cystic


  • Rawabdeh, Ali Ahmad, University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States
  • Hasan, Irtiza, University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States
  • Heilig, Charles W., University of Florida College of Medicine - Jacksonville, Jacksonville, Florida, United States

A late presentation of functional renal impairment without structural changes in a patients with Townes-Brocks Syndrome (TBS).

Case Description

A 48-year-old male patient with no significant past medical history presented to Nephrology clinic with incidental diagnosis of abnormal renal function on routine blood work. He does not endorse any other concomitant clinical symptoms including genito-urinary symptoms, denies regular use of NSAIDs, history of drug abuse or any history of hepatitis or HIV. Lab works showed elevated serum creatinine at 1.81 mg/dL and GFR of 46, urine albumin 1+, protein/creatinine ratio of 192 mg/g (in 24 hours), positive ANA (homogenous; 1:160) with normal C3, C4, C-ANCA and P-ANCA. Other CKD labs were reviewed and found to be within normal range. Serum protein electrophoresis and immunofixation did not reveal any monoclonal paraproteinemia. Renal ultrasound showed normal sized kidneys with increased echogenicity bilaterally, but no structural changes or hydronephrosis. No specific aetiology for CKD was identified. Coincidently, his son was born with one kidney as a part of congenital Townes-Brocks syndrome with chromosome analysis showing abnormality in chromosome 19, which is autosomal dominant and paternally inherited. Paternal chromosome analysis revealed similar diagnosis with heterozygous genotype.


Towne-Brock’s syndrome (TBS) is a rare autosomal dominant condition resulting from heterozygous variant in SALL1 gene and characterized by triad of imperforate anus, dysplastic ears and hand malformation. Renal impairment occurs in 42% of cases including ESRD with or without structural abnormalities and malformations. However, data on long term prognosis of renal involvement, slope of declining renal function and risk of developing renal failure is lacking. Thus, yearly renal function assessment throughout the life is indicated for patients with TBS as well as those with first degree relatives with TBS. Also, there is a need to determine the evidence of SALL1 mutation in patients with late-onset functional kidney disease without structural changes as well as in those with nephropathies of unknown origin in adulthood.