Needle-Stick Injury, a Late Disclosure, and a Sterilisation Failure
You are the dentist in a two-chair practice. At 4:40 pm, while giving an inferior alveolar nerve block to a 34-year-old man, the patient jerks and you sustain a needle-stick injury to the pad of your left index finger with the 27-gauge needle that had just been in his mouth. The wound bleeds.
While you are washing it, he tells you he is HIV-positive, diagnosed four years ago, and takes dolutegravir/tenofovir/emtricitabine with an undetectable viral load. He did not disclose this on the medical history form because "it's private and it doesn't affect my teeth". You were vaccinated against hepatitis B as a student but have never had a titre checked.
At 4:50 pm the practice nurse tells you that the autoclave log has no recorded cycle for the previous Friday and that three pouches from that day had failed indicator strips - but the instruments were used on patients that afternoon.
1. Set out your immediate actions in the first hour, with timeframes, and the serology and post-exposure plan for each virus.
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First aid, immediately: wash the wound with soap and running water, do not scrub or squeeze it, do not use bleach or alcohol, dry it and cover it. Report to the practice manager and open an incident report. Time is the critical variable - if HIV PEP is indicated it should start within 1–2 hours, and no later than 72 hours.
Risk assessment: percutaneous injury with a hollow-bore needle and visible blood, from a source with HIV who reports an undetectable viral load on stable ART. The risk is low but not zero; the specialist will weigh the viral load, needle gauge, depth and your own status.
Go to the emergency department or occupational health now, with the patient's consent, for source testing: HIV antigen/antibody, HBsAg, anti-HBc, anti-HBs and HCV antibody/RNA. Take your own baseline serology at the same time.
- HIV: the decision about 28 days of PEP belongs to the infectious diseases physician, made today. With a confirmed undetectable viral load they may advise that PEP is not required - that is their call, not one to make alone at 5 pm.
- Hepatitis B: check your anti-HBs. If it is under 10 IU/mL or unknown, hepatitis B immunoglobulin plus a vaccine booster is indicated within 24 hours, ideally 12.
- Hepatitis C: no PEP exists. Baseline HCV RNA, repeat at 4–6 weeks and again at 12–24 weeks; if seroconversion occurs, direct-acting antivirals cure over 95%.
Follow-up HIV testing at 6 weeks, 3 months and 6 months; document everything and inform your own GP.
2. How do you handle the sterilisation lapse - investigation, tracing patients, and disclosure?
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Treat it as a clinical incident with the same rigour as the needle-stick.
Contain it first: quarantine all instruments processed since the failed cycles and do not release them for use until the steriliser has been validated. Check the autoclave's physical parameters, chemical indicators and biological indicators against the standard the practice works to (AS/NZS 4815 for office-based practices, AS/NZS 4187 for hospital-style reprocessing). Do not use the machine again until it passes.
Trace it: use the sterilisation log batch numbers and the appointment book to identify exactly which instruments were used on which patients that afternoon. Poor record-keeping may make this uncertain - say so rather than guessing.
Assess and disclose: the transmission risk from a failed indicator cycle is very low but not zero, and hepatitis B can survive on dried surfaces for days. Patients have the right to be fully informed (Code of Health and Disability Services Consumers' Rights, Right 6) and to services of an appropriate standard (Right 4). Contact every affected patient, explain what happened in plain language, explain the low risk and what testing is offered, apologise, and document the conversation. Open disclosure is expected and is better done by you than discovered later.
Report through the practice's quality and risk system, notify your indemnifier and the practice owner, and consider notifying the Dental Council if a complaint or harm follows. Then fix the system: single-use indicators, cycle logging, staff training and a daily validation check.
3. What are your obligations around the patient's late disclosure of HIV status, privacy, and your own fitness to practise?
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Privacy: his HIV status is confidential. Share it only with the people who need it to manage the exposure - the emergency physician and occupational health - and preferably with his explicit consent. Do not tell reception, the nurse or the other dentist. Record it in the notes accurately, because it is clinically relevant, but do not broadcast it.
His non-disclosure: patients are not obliged to disclose HIV status, and an incomplete medical history never removes the duty to use standard precautions for every patient. Do not confront or blame him; his concern about privacy is legitimate and he may have experienced discrimination. Do not refuse further treatment or treat him differently. Tell him what you are obliged to share and with whom, and get his consent for source testing and for sharing the result.
Your fitness to practise: you are not restricted from working while awaiting results. Complete your follow-up testing, and if you were to seroconvert, take occupational health advice before continuing exposure-prone procedures. Inform your own GP.
The practice: the needle-stick was preventable - review sharps policy (no recapping, immediate disposal in sharps containers at the chairside, safety-engineered devices, a second pair of hands for difficult injections), and run the sterilisation failure as a formal incident review with actions and a review date. Document your own reflection; both events are the kind of thing a regulator would expect to see handled openly and systematically.