Medical Emergencies · patient case with 1 question
Extraction in a patient with multiple myeloma
Patient: Male, 66 years old
Chief Complaint: “My physician cleared me. This back tooth has to come out.”
Background: Multiple myeloma diagnosed fourteen months ago, currently on lenalidomide and dexamethasone. He has never received an intravenous bisphosphonate or denosumab. No cardiac history, no prosthetic valve, no prosthetic joint, no indwelling central line.
Laboratory: Hb 10.2 g/dL · Platelets 142,000/µL · Absolute neutrophil count 2,100/µL
Vital Signs: BP 128/78 mmHg · HR 76 bpm · T 98.4°F
Findings: Tooth #30 is non-restorable with a periapical radiolucency. The remaining dentition is sound.
Question 1
What is the appropriate approach to antibiotic prophylaxis before this extraction?
Show answer and explanation
Correct answer: B. No prophylaxis is indicated — proceed with routine care
- A. Amoxicillin 2 g one hour preoperatively is the correct REGIMEN, but only when there is an indication for it. The indication is what is missing here.
- B. CORRECT. Prophylaxis is driven by the 2021 AHA cardiac criteria — a prosthetic valve or prosthetic material used in valve repair, previous infective endocarditis, unrepaired cyanotic congenital heart disease or repaired disease with a residual defect, and cardiac transplant valvulopathy. A haematological malignancy appears on none of those lists. In an oncology patient the question that actually matters is the degree of MYELOSUPPRESSION, and this patient's absolute neutrophil count of 2,100/µL is normal. With a normal neutrophil count, no antiresorptive exposure and no indwelling line, routine extraction proceeds without prophylaxis.
- C. Clindamycin was REMOVED from the 2021 AHA prophylaxis regimen because of its Clostridioides difficile risk. It would be the wrong drug even if an indication existed.
- D. A multi-day course is therapeutic treatment, not prophylaxis. Prophylaxis is a single dose given within the hour before the procedure so that tissue concentrations peak during the bacteraemia.
Note: What WOULD change management in a myeloma patient is antiresorptive therapy. Zoledronate and denosumab are standard care for myeloma bone disease and carry a substantial MRONJ risk with extraction — this patient happens not to be on one, which is precisely why the medication list must be read before the diagnosis is acted on. Consult the oncologist when the ANC falls below roughly 1,000/µL, when platelets are low enough to threaten haemostasis, or when a central venous catheter is in place.