Immune hemolytic anemia induced by 6-mercaptopurine.
BACKGROUND
Myelosuppression is the main hematotoxic effect of 6-mercaptopurine (6-MP), which is an antimetabolite chemotherapy drug. Immune hemolytic anemia associated with this drug has not been previously reported.


METHODS
A 67-year-old man with chronic myelomonocytic leukemia presented with anemia 2 weeks after 6-MP therapy had been initiated. Additional tests provided laboratory evidence of hemolysis. When treatment was stopped, the patient's condition and laboratory results showed a progressive improvement.


RESULTS
The direct antiglobulin test was positive for IgG. The eluate and the serum were not reactive with panel red cells but reacted with 6-MP-treated red cells, while the normal serum pool was unreactive. The direct antiglobulin test was no longer positive by 20 days after the cessation of 6-MP therapy.


CONCLUSIONS
This drug, 6-MP, should be added to the list of drugs that have been reported to cause immune hemolytic anemia by means of the so-called hapten mechanism.
Pujol
M
M
Hematology and Hematotherapy Service, Hospital Universitario Germans Trias i Pujol, Badalona, Spain. 7963mpb@comb.es
Fernández
F
F
Sancho
J M
JM
Ribera
J M
JM
Millá
F
F
Feliu
E
E
D000368:Aged; D000744:Anemia, Hemolytic, Autoimmune / Q000139:chemically induced*; D003298:Coombs Test; D006801:Humans; D015477:Leukemia, Myelomonocytic, Chronic / Q000188:drug therapy; D008297:Male; D015122:Mercaptopurine / Q000009:adverse effects*
D015122:Mercaptopurine