Diclofenac-induced antibodies against RBCs and platelets: two case reports and a concise review.
BACKGROUND
Diclofenac has frequently been implicated as the cause of immune hemolytic anemias and less frequently of immune thrombocytopenia. The presence of the causative antibodies has only been demonstrated in patients with immune hemolytic anemia, but not yet in patients with thrombocytopenia. The cases of two patients in whom diclofenac simultaneously induced antibodies against platelets and RBCs are reported.


METHODS
The investigation was carried out with standard serologic tests for detection of antibodies against platelets and RBCs. The patients' sera were tested in the presence and absence of diclofenac and its metabolites.


RESULTS
One of the two patients developed severe hemolysis and significant thrombocytopenic purpura. The other patient developed significant thrombocytopenia but no hemolysis. Both patients had a positive DAT and drug- and/or metabolite-dependent antibodies against RBCs and platelets.


CONCLUSIONS
Based on our findings and those of other investigators, we believe that diclofenac leads to the production of antibodies against RBCs and/or platelets.
Meyer
Oliver
O
University Clinic Charité, Institute for Transfusion Medicine, Humboldt University of Berlin, Germany. oliver.meyer@charite.de
Hoffmann
Till
T
Aslan
Tunay
T
Ahrens
Norber
N
Kiesewetter
Holger
H
Salama
Abdulgabar
A
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D001381:Azepines; D001792:Blood Platelets / Q000276:immunology*; D003298:Coombs Test; D004008:Diclofenac / Q000009:adverse effects*; D004912:Erythrocytes / Q000276:immunology*; D005260:Female; D006461:Hemolysis; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D007191:Indazoles; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000276:immunology; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000276:immunology; D010980:Platelet Membrane Glycoproteins; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000139:chemically induced*
D001323:Autoantibodies; D001381:Azepines; D015395:Histocompatibility Antigens Class I; D007191:Indazoles; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D019038:Platelet Glycoprotein GPIb-IX Complex; D010980:Platelet Membrane Glycoproteins; C032193:glycoprotein receptor GPIb-IX; C073385:DAT 582; D004008:Diclofenac