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.
Yoshinari
Miyako
M
Department of Pediatric Oncology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Japan. myoshinari@idac.tohoku.ac.jp
Kunishima
Shinji
S
Miyabayashi
Shigeaki
S
Saito
Hidehiko
H
Tsuchiya
Shigeru
S
D001792:Blood Platelets / Q000473:pathology; D004396:Coloring Agents; D004252:DNA Mutational Analysis; D004801:Eosine Yellowish-(YS); D005455:Fluorescent Antibody Technique / Q000379:methods*; D005838:Genotype; D006801:Humans; D002479:Inclusion Bodies / Q000473:pathology; D007223:Infant; D007962:Leukocytes / Q000473:pathology; D008297:Male; D008751:Methylene Blue; D008854:Microscopy, Electron; D020409:Molecular Motor Proteins / Q000235:genetics; D018995:Myosin Heavy Chains / Q000235:genetics; D010976:Platelet Count; D013347:Subcellular Fractions; D013921:Thrombocytopenia / Q000175:diagnosis* / Q000235:genetics
D004396:Coloring Agents; C103814:MYH9 protein, human; C043260:May-Grunwald Giemsa; D020409:Molecular Motor Proteins; D018995:Myosin Heavy Chains; D008751:Methylene Blue; D004801:Eosine Yellowish-(YS)