PO25 - MYH9 related disorder: A benign R1933* MYH9 mutation with nephrology

Wednesday, June 28, 2023

13:00 – 14:00 ET

Room: 10

Presenting Author(s)

Dongmei Xie, MA

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)

Co-Author(s)

Wen Yang, MA

Doctor
Department of Hematology, The Second Affiliated Hospital of Kunming Medical University, Yunnan, China
Kunming, Yunnan, China (People's Republic)
YW

Yacan Wang

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)
ZF

Zhihui Feng

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)
RL

Renxia Li

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)
SZ

Shiqi Zhang

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)
ZZ

Zeping Zhou

Doctor
The Second Affiliated Hospital of Kunming Medical University
Kunming, Yunnan, China (People's Republic)

Background: MYH9-associated disorder (MYH9-RD) is a hereditary thrombocytopenia caused by mutations in MYH9 gene. Mutations in MYH9 gene initially affect the hemic system, including giant platelets, thrombocytopenia, and granulocyte inclusions. Other clinical manifestations (nephropathy, deafness, and cataracts) may develop with age. But not all patients develop nephropathy. And studies showed proteinuria is the earlier sign of kidney involvement in MYH9-RD, progresses to end stage renal disease (ESRD) when a patient reaches his/her thirties.

Aims: The aim of this study was to raise awareness of MYH9-associated nephropathy.

Methods: A retrospective review of the patient’s medical history was performed.

Results: Platelet count showed thrombocytopenia. Bone marrow cytology showed the cytoplasm of some granulocytes showed 2-3 oval and spindle inclusions presenting obvious blue, located in the cytoplasm or near the cell membrane, and platelets were rare and most of them are large. Gene sequencing analysis of the proband and his family members showed that the patient, his old brother, and old sister had a c. 5797C>T (p. Arg1933*) mutation in exon 41 of MYH9 gene. Thus, the patient was diagnosed with MYH9-associated disorder.
Among the complications he had not deafness, and cataracts, but had abnormal manifestations of kidney, including Urine occult blood (+++) and Urine protein (+).
He had acute nephritis, bellyache, and some abnormalities in immune-related tests, including anti-thyroglobulin antibody, anti - Ro - 52 and anti-CENPB.
Management relies on a rapid and accurate diagnosis. No bleeding tendency in our patient’s normal life, no special treatment is required. We need to further tests for the kidney. In MYH9-associated nephropathy, the treatment of ACEI or ARBs to control proteinuria levels to further slow the progression to ESRD.

Conclusion(s): MYH9-associated nephropathy may occur in mutations of the NHT region in the MYH9 gene and progress to end stage renal disease (ESRD). This case may raise awareness of MYH9-associated nephropathy.