Infection Control · patient case with 2 questions
Needlestick before patient contact in an HIV-positive patient
Scenario: An HIV patient came for an extraction. During the anaesthetic procedure, the dentist OPENS THE CAP BEFORE CONTACTING THE PATIENT and gets a NEEDLE STICK.
Question 1
What do you do?
Show answer and explanation
Correct answer: C. Replace everything — carpule, needle, syringe and gloves — and proceed
- A. Post-exposure prophylaxis is indicated only after a TRUE exposure to potentially infectious material. Antiretrovirals carry real toxicity and are not started without an exposure.
- B. There is no exposure and therefore no emergency; sending the patient anywhere would be alarming and unnecessary.
- C. Correct — and the critical detail is TIMING. The needle had NOT yet contacted the patient, so it was STERILE and there was NO exposure to the patient's blood or body fluids. There is no transmission risk. The dentist washes the wound, replaces the contaminated armamentarium and gloves, documents the incident, and proceeds.
- D. This is not an emergency requiring EMS activation.
Note: ⚠️ READ THE STEM CAREFULLY — this is the entire point of the question. Had the needle been used on the patient FIRST, the protocol would be: wash the wound with soap and water; report immediately to the designated infection control officer; test the source patient and the exposed worker; and start PEP WITHIN 1-2 HOURS (and ideally within 72 hours). Transmission risk from a percutaneous exposure is roughly 0.3% for HIV, about 1.8% for HCV, and up to 30% for HBV in an unvaccinated worker.
Question 2
In this HIV patient, all of the following contribute to candidiasis EXCEPT:
Show answer and explanation
Correct answer: B. Increased vertical dimension of occlusion
- A. Broad-spectrum antibiotics suppress the competing bacterial flora and permit candidal overgrowth.
- B. Correct — this is the EXCEPTION. It is a DECREASED vertical dimension that predisposes to candidiasis, by deepening the labial commissural folds so that saliva pools there and macerates the tissue, producing ANGULAR CHEILITIS. An increased vertical dimension does not promote candidal overgrowth.
- C. Xerostomia removes the flushing action, antimicrobial proteins and immunoglobulins of saliva, allowing candidal overgrowth.
- D. Immunosuppression — particularly a falling CD4 count in HIV — is a major predisposing factor; oral candidiasis is frequently the first clinical sign of HIV progression.
Note: Other predisposing factors worth listing: inhaled corticosteroids without rinsing, denture wear (especially overnight), diabetes, smoking, infancy and old age, and nutritional deficiency.