Trimethoprim‐sulphamethoxazole‐associated blood dyscrasias. Ten years'experience of the Swedish spontaneous reporting system

Abstract

During the 10-year period 1976-1985, a total of 154 cases of blood dyscrasia were reported in Sweden which were evaluated as having a probable or possible causal relationship with trimethoprim-sulphamethoxazole (T-SM). There were 61 cases of leucopenia (of which 16 had agranulocytosis), 28 cases of thrombocytopenia, and two of non-haemolytic anaemia. There were also 32 cases of bicytopenia and 31 cases of tricytopenia. The median age varied from 38 years in the leucopenia group to 81 years in those with tricytopenia. The overall fatality rate was 17%, ranging from 2% in the group with mild leucopenia to 52% in the group with tricytopenia. In relation to sales and prescription data, the overall incidence of reported T-SM blood dyscrasias was 5.3 per million defined daily doses, and among out-patients the incidence was one case per 18,000 prescriptions. Thus the overall incidence of any blood reaction to T-SM appears to be low. In relation to prescription data, elderly people were overrepresented among the serious reactions.

Anemia in combined antiretroviral treatment-naive HIV-infected patients in China: A retrospective study of prevalence, risk factors, and mortality

“…Although SMX-TMP administration may cause drug-induced aplastic anemia, several studies (30,31) failed to find this association. Keisu et al (31) found that SMX-TMP induced anemia, but that this effect was sporadic.…”

Incidence, Risk Factors and Clinical Consequences of Neutropenia Following Kidney Transplantation: A Retrospective Study

“…, tacrolimus (5), sirolimus (6), cotrimoxazole (7), omeprazole (8), rituximab (9) and angiotensin converting enzyme inhibitors (10). Drug imputability often remains difficult to establish directly, and regression of neutropenia after drug discontinuation can be used as indirect evidence.…”

Considerations when prescribing trimethoprim-sulfamethoxazole

“…The incidence of severe hematologic toxicity is unknown, but estimates range up to 1.7-5.5/100 000 prescriptions. 9,10 Several mechanisms have been implicated and described in case reports ( Table 2). Generation of antibodies to the glycoprotein IIb/IIIa complex on platelets can cause immune thrombocytopenia, which is typically observed within the first week of treatment and is generally reversible on discontinuation of the drug.…”