A Unique Immunofluorescence Method Promotes Accurate Diagnosis in MYH9 Disorders: A Case Report.
The identification of a mutation in the MYH9 gene in hereditary macrothrombocytopenia has established a distinct entity proposed as "MYH9 disorders," which previously have often been misdiagnosed as chronic immune thrombocytopenic purpura. The authors describe clinical and laboratory characterization of a family with the disorder demonstrating giant platelets, thrombocytopenia, and leukocyte inclusion bodies. The authors emphasize the efficacy of a unique immunofluorescence method for the nonmuscle myosin heavy chain A in the diagnosis, because it is more sensitive than May-Grünwald-Giemsa staining and more practical than electron microscopy or direct sequencing. MYH9 disorders may be much more common than previously realized if accurately diagnosed.
From the *Department of Pediatric Oncology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Japan; †Department of Hemostasis and Thrombosis, Clinical Research Center, Nagoya National Hospital, Nagoya, Japan; ‡Department of Pediatrics, National Sendai Hospital, Sendai, Japan; and §Nagoya National Hospital, Nagoya, Japan.
Miyako
M
Yoshinari
Shinji
S
Kunishima
Shigeaki
S
Miyabayashi
Hidehiko
H
Saito
Shigeru
S
Tsuchiya