Variations in the monitoring and management of the side effects of antirheumatic drugs by means of laboratory tests.
OBJECTIVE
To ascertain the strategies Dutch rheumatologists would employ in the monitoring of side effects of non-steroidal anti-inflammatory drugs (NSAIDs) and disease modifying antirheumatic drugs (DMARDs) by means of laboratory tests, and in the management of detected toxicity.


METHODS
A questionnaire was sent to all practicing Dutch rheumatologists concerning NSAIDs and the following DMARDs: antimalarials (AMALs), intramuscular gold (Au), d-penicillamine (DPEN), sulfasalazine (SASP), methotrexate (MTX) and azathioprine (AZA).


RESULTS
The response rate was 72% (83/114). Except for AMALs, at least 90% of rheumatologists determined the haemoglobin concentration during NSAID or DMARD therapy, the white blood cell (WBC) and platelet count during DMARD, serum creatinine and transaminases during MTX, and proteinuria during Au and DPEN therapy. At least 88% did not request a urinalysis when prescribing AMALs, and serum bilirubin and albumin when prescribing all drugs. The majority used monitoring intervals of < 3 months when prescribing DMARDs (except for AMALs) during the induction phase of therapy and during the maintenance phase in the case of Au and MTX treatment. For all DMARDs except AMALs, 65% to 75% would change the treatment when the WBC count was 2.5-3.4 x 10(9)/l. When the platelet count was 100-150 x 10(9)/l, 67% to 85% would not. The percentage of rheumatologists that would change the medication when the transaminase levels were 2 to 3 times the upper limit of normal or when proteinuria was 0.5-1.0 g/l varied considerably irrespective of the drug involved.


CONCLUSIONS
The strategies that Dutch rheumatologists would employ showed uniformity in the choice for some laboratory tests, but also showed considerable variation in the case of other tests, the monitoring intervals, and treatment interventions.
Simon
C H
CH
Department of Rheumatology, Leiden University Hospital, The Netherlands.
Dijkmans
B A
BA
Breedveld
F C
FC
D016907:Adverse Drug Reaction Reporting Systems; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects*; D018501:Antirheumatic Agents / Q000009:adverse effects*; D019411:Clinical Laboratory Techniques / Q000706:statistics & numerical data; D016903:Drug Monitoring / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D010818:Practice Patterns, Physicians'; D012219:Rheumatology / Q000592:standards* / Q000706:statistics & numerical data
D000894:Anti-Inflammatory Agents, Non-Steroidal; D018501:Antirheumatic Agents