Quinine-induced thrombocytopenia

In one patient with AIDS with severe but reversible thrombocytopenia after intravenous pentamidine, the serum during the acute phase contained antiplatelet antibodies that reacted with glycoprotein Ilb/IIIa, similar to the reactions observed with quinine-induced thrombocytopenia (SEDA-18, 292). This suggests that even aerosol treatment or environmental exposure will need to be avoided in such patients. 

Christie DJ, Mullen PC, Aster RH (1985) Fab-mediated binding of drug-dependent antibodies to platelets in quinidine- and quinine-induced thrombocytopenia. J Clin Invest 75 310-314 Cunha PD, Lord RS, Johnson ST, Wilker PR, Aster RH, Bougie DW (2000) Immune hemolytic anemia caused by sensitivity to a metabolite of etodolac, a nonsteroidal anti-inflammatory drag. Transfusion 40 663-668... 

Brasic, J.R., and M. Baltimore. 2001. Quinine-induced thrombocytopenia in a 64-year-old man who consumed tonic water to relieve nocturnal leg cramps. Mayo Clin. Proc. 76(8) 863. 

The unambiguous demonstration, in presumptive allergic reactions, of immunochemical specificity determined by drug-derived haptenic structures, is absent in the majority of cases, with the exception of some instances of contact allergic dermatitis induced by antifungal agents applied topically. In this chapter immunochemical specificity is discussed also in relation to the antibodies responsible for quinine-induced thrombocytopenia and levamisole-induced anti-leucocyte antibodies in agranulocytosis. 

In summary, allergic reactions are not a problem in treatment of protozoal infections. The aetiology of quinine-induced thrombocytopenia remains a fascinating immunological problem for future study. 

Bougie DW, Birenbaum J, Rasmussen M, Poncz M, Aster RH. (2008) Quinine-dependent, platelet-reactive monoclonals mimic antibodies found in patients with quinine-induced immune thrombocytopenia. Blood 113 1105-1111. 

The use of quinidine and quinine should be avoided in patients who previously showed evidence of quini-dine-induced thrombocytopenia. 

Quinidine Quinidine, molecular formula C20H24N2O2, is a stereoisomer of quinine found in Cinchona bark. Chemically, it is known as (2-ethenyl-4-azabicyclo[2.2.2]oct-5-yl)-(6-methoxyquinolin-4-yl)-methanol, or 6 -methoxycinchonan-9-ol. It is used as a Class 1 anti-arrhythmic agent. Intravenous injection of quinidine is also used in the treatment of P. falciparum malaria. Among the adverse effects, quinidine induces thrombocytopenia (low platelet counts) and may lead to thrombocytic purpurea. 

Christie DJ, Aster RH (1982) Drag-antibody-platelet interaction in quinine- and quinidine-induced thrombocytopenia. J Clin Invest 70 989-998... 

Garratty G, Amdt P, Prince HE, Shulman lA (1993) The effect of methyldopa and procainamide on suppressor cell activity in relation to red cell autoantibody production. Br J Haematol 84 310-315 Gottschall JL, Elliot W, Lianos E, McFarland JG, Wolfmeyer K, Aster RH (1991) Quinine-induced immune thrombocytopenia associated with hemolytic uremic syndrome a new clinical entity. Blood 77 306-310... 

Quinine (Fig. 9) is probably the oldest effective therapeutic agent for the prophylaxis and therapy of Plasmodium infections and, although now largely superseded for routine use, it is of considerable value in the treatment of chloroquine-resistant P. falciparum, for which it is used in combination with other antimalarials. The main side effects of quinine therapy comprise a syndrome of classical cinchonism, i.e., tinnitus, vision defects, nausea, headache and gastrointestinal effects, but im-munologically the much rarer complication, drug-induced thrombocytopenia is of more interest. 

A striking case of drug-induced thrombocytopenia was reported by Rennie et al. in a patient who had been taking 0.3 g of quinine at bedtime for 3 years for intermittent claudication (19 -). In this particular case a dental extraction nearly proved fatal, and it was only on the second admission to hospital that the diagnosis was made. 

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