A patient taking Methotrexate and Adalimumab (Humira) requires laboratory monitoring. Which test is most critical to order?

Methotrexate is a disease-modifying antirheumatic drug (DMARD) that requires regular monitoring of: (1) Complete blood count (CBC) - to detect bone marrow suppression (pancytopenia); (2) Liver function tests (AST, ALT) - methotrexate is hepatotoxic and the ACR recommends liver enzyme monitoring every 2-4 weeks initially, then every 8-12 weeks; (3) Renal function (creatinine) - methotrexate is renally cleared, and renal impairment causes toxic accumulation. Adalimumab (a TNF-alpha inhibitor) requires baseline TB screening and periodic CBC. In dentistry, patients on these immunosuppressants are at increased infection risk and may have impaired healing.