TY - JOUR
T1 - Polycythemia from mast cell activation syndrome
T2 - Lessons learned
AU - Afrin, Lawrence B.
PY - 2011/7
Y1 - 2011/7
N2 - A middle-aged woman presented with fatigue and mild increases in hematocrit and red cell mass. Polycythemia vera was diagnosed. She underwent therapeutic phlebotomy but clinically worsened. On reevaluation, other problems were noted including episodic malaise, nausea, rash and vasomotor issues. The JAK2V617F mutation was absent; paraneoplastic erythrocytosis was investigated. Serum tryptase and urinary N-methylhistamine were normal, but urinary prostaglandin D2 was elevated. Skin and marrow biopsies showed no mast cell abnormalities. Extensive other evaluation was negative. Gastrointestinal tract biopsies were histologically normal but revealed increased, aberrant mast cells on immunohistochemistry; the KITD816V mutation was absent. Mast cell activation syndrome, recently identified as a clonal disorder involving assorted KIT mutations, was diagnosed. Imatinib 200 mg/d rapidly effected complete, sustained response. Diagnosis of mast cell activation syndrome is hindered by multiple factors, but existing therapies for mast cell disease are usually achieve significant benefit, highlighting the importance of early diagnosis. Multiple important aspects of clinical reasoning are illustrated by the case.
AB - A middle-aged woman presented with fatigue and mild increases in hematocrit and red cell mass. Polycythemia vera was diagnosed. She underwent therapeutic phlebotomy but clinically worsened. On reevaluation, other problems were noted including episodic malaise, nausea, rash and vasomotor issues. The JAK2V617F mutation was absent; paraneoplastic erythrocytosis was investigated. Serum tryptase and urinary N-methylhistamine were normal, but urinary prostaglandin D2 was elevated. Skin and marrow biopsies showed no mast cell abnormalities. Extensive other evaluation was negative. Gastrointestinal tract biopsies were histologically normal but revealed increased, aberrant mast cells on immunohistochemistry; the KITD816V mutation was absent. Mast cell activation syndrome, recently identified as a clonal disorder involving assorted KIT mutations, was diagnosed. Imatinib 200 mg/d rapidly effected complete, sustained response. Diagnosis of mast cell activation syndrome is hindered by multiple factors, but existing therapies for mast cell disease are usually achieve significant benefit, highlighting the importance of early diagnosis. Multiple important aspects of clinical reasoning are illustrated by the case.
KW - Imatinib
KW - Mast cell activation syndrome
KW - Polycythemia
UR - http://www.scopus.com/inward/record.url?scp=79959902876&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79959902876&partnerID=8YFLogxK
U2 - 10.1097/MAJ.0b013e31821d41dd
DO - 10.1097/MAJ.0b013e31821d41dd
M3 - Article
C2 - 21642812
AN - SCOPUS:79959902876
SN - 0002-9629
VL - 342
SP - 44
EP - 49
JO - American Journal of the Medical Sciences
JF - American Journal of the Medical Sciences
IS - 1
ER -