Detection of unique neutrophil non-muscle myosin heavy chain-A localization by immunofluorescence analysis in MYH9 disorder presented with macrothrombocytopenia without leukocyte inclusions and deafness.
MYH9 disorders are autosomal-dominant macrothrombocytopenias with leukocyte inclusions caused by mutations in the MYH9 gene, which encodes the non-muscle myosin heavy chain-A (NMMHCA). We report a patient with an MYH9 disorder who presented with macrothrombocytopenia without leukocyte inclusions and severe bilateral sensory deafness. Conventional May-Grunwald-Giemsa staining failed to detect granulocyte cytoplasmic inclusions, whereas immunofluorescence analysis clearly demonstrated abnormal neutrophil NMMHCA localization. Genetic analyses revealed a novel heterozygous 18 base deletion in MYH9, leading to a six-amino acid in-frame deletion (N76_S81del) in NMMHCA. These results further support the usefulness of immunofluorescence analysis in differential diagnosis of MYH9 disorders.
Kunishima
Shinji
S
Department of Hemostasis and Thrombosis, Clinical Research Center, Nagoya Medical Center, Nagoya, Japan. kunishis@nnh.hosp.go.jp
Matsushita
Tadashi
T
Shiratsuchi
Motoaki
M
Ikuta
Takuya
T
Nishimura
Junji
J
Hamaguchi
Motohiro
M
Naoe
Tomoki
T
Saito
Hidehiko
H
D000595:Amino Acid Sequence; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004252:DNA Mutational Analysis; D003638:Deafness / Q000235:genetics; D003937:Diagnosis, Differential; D005799:Genes, Dominant; D006801:Humans; D002479:Inclusion Bodies / Q000473:pathology; D007962:Leukocytes / Q000473:pathology; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D008958:Models, Molecular; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000235:genetics*; D018995:Myosin Heavy Chains / Q000097:blood* / Q000737:chemistry / Q000235:genetics*; D009504:Neutrophils / Q000378:metabolism* / Q000473:pathology; D011487:Protein Conformation; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D013921:Thrombocytopenia / Q000097:blood* / Q000175:diagnosis / Q000235:genetics*
C103814:MYH9 protein, human; D020409:Molecular Motor Proteins; D004247:DNA; D018995:Myosin Heavy Chains