Surgeon, test (and heal) thyself: sharps injuries and hepatitis C risk

Surgeons and others who perform exposure-prone procedures are at risk of contracting blood-borne viruses, but do not always recognise or report potential exposures. They may be reluctant to report sharps injuries, or to present for testing for blood-borne virus transmission, for fear of being barred from surgical practice. Although surgeons may fear transmission of HIV in particular, it is hepatitis C that poses the greatest risk. 1,2 Estimates of this risk have sometimes included an alarmingly high predicted cumulative incidence of hepatitis C. 3 However, cross-sectional studies show the actual seroprevalences of hepatitis C in surgeons to be equivalent to, or slightly higher than, those of the general population. 4,5 Therefore, the risk seems to be considerably lower than might be predicted, and can be estimated by the formula in Box 1.

From this formula, a surgeon who performs 300 procedures per year and is at the end of a 35-year surgical career has a risk of 4.9% of being HCV antibody-positive, with a 3.8% risk of being RNA-positive on polymerase chain reaction testing (people are not infectious and will not develop any disease unless they are HCV RNA-positive). The lower and upper bounds of being RNA-positive using the highest published estimates of Pr(si) and Pr(trans) are 3.2% and 26.3%. The estimated prevalence of RNA positivity (using the most commonly accepted average probabilities) after 15 years of surgical practice (ie, mid-career) is 1.6% (equivalent to the general population).

Surgeons who are HCV-positive pose a low, but definite potential, risk to patients. As acute hepatitis C is usually asymptomatic, infection will often be unrecognised. Although several published cases have documented surgeon-to-patient transmission,11-13 the investigations that have followed such cases have generally shown no or minimal exposure in other patients of these surgeons — transmission rates of 0.036%–2.2%. 12,13 An estimate of risk to an individual patient from a surgeon known to be HCV antibody-positive and RNA-positive is shown in Box 2.

The overall probability of transmission in such a situation is 0.0001 (or 1 per 10 000 procedures). This is somewhat lower than some published estimates, which have used higher probabilities for some variables. 7,14

If a surgeon sustains a known sharps injury from an RNA-positive patient, protocols for testing vary. A recommended protocol is RNA testing at 4 weeks, followed by anti-HCV testing at 8 and 12 weeks. 2 Tests for RNA usually become positive between 10 days and 6 weeks after infection. The risk that a surgeon might transmit hepatitis C during this window period is derived by multiplying the formula in Box 2 by the transmission risk to surgeon (1.8%), so that the overall risk to an individual patient is 0.000002, or 2 per million procedures.

The major advantage of early testing is access for the surgeon to probable cure. Jaeckel et al showed that, of 44 German patients treated with high-dose interferon monotherapy, 99.5% achieved a cure. 16 There was no control group, and historical data were used. These patients differed from the situation in exposed surgeons, as almost all patients were symptomatic. However, the distribution of genotypes was similar to that in Australia. Most patients (61%) had genotype 1 (the more “difficult to treat” genotype). The patients received 5 million units of interferon alfa-2b subcutaneously daily for 4 weeks, followed by 5 million units three times a week for another 20 weeks. Despite these relatively high doses, there were no serious adverse effects. Only one patient withdrew (at 12 weeks, because of hair loss and flu-like symptoms).

A recent German–Egyptian study indicates that pegylated interferon combined with ribavirin can achieve results similar to those with high-dose interferon. 17 This treatment has fewer adverse effects than non-pegylated interferon. Sustained virological response was a little lower than in the Jaeckel study (85% for combination pegylated interferon–ribavirin, and 80% for pegylated interferon monotherapy). 16 This may be because treatment was not commenced until 16 weeks after HCV infection, compared with a mean of 89 days in the Jaeckel study. Some people advocate a similar strategy (ie, waiting for 3, or even 4, months) in all acutely infected individuals, as up to 30% of people clear the virus spontaneously. However, this extra time may affect treatment outcome adversely. Moreover, in the case of surgeons, this would necessitate an additional 2–3 months during which the surgeon would be known to be RNA-positive (at 4 weeks after exposure), but would be unable to operate.

Treatment for chronic hepatitis C has a 50% (range, 40%–85%) cure rate,18 but earlier detection of hepatitis C (ie, within 12 months of infection) allows a greater chance of cure, somewhere between 50% (cure rate for chronic infection) and 99% (cure rate for early acute infection). 16