A 26-year-old student comes to the emergency department 10 hours after his right arm was scratched by a bat. He says, "I frequently explore caves, and bats do not always seem to like me." He had a similar scratch 1 year ago and completed his anti-rabies vaccination series. All his vaccinations are up-to-date. His past medical history is otherwise insignificant. He does not use tobacco, alcohol, or illicit drugs. He is currently not taking any medications and has no known allergies. What is the best management strategy for this patient?

Question

A 26-year-old student comes to the emergency department 10 hours after his right arm was scratched by a bat.  He says, "I frequently explore caves, and bats do not always seem to like me."  He had a similar scratch 1 year ago and completed his anti-rabies vaccination series.  All his vaccinations are up-to-date.  His past medical history is otherwise insignificant.  He does not use tobacco, alcohol, or illicit drugs.  He is currently not taking any medications and has no known allergies.  What is the best management strategy for this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_bfbc_1e7d_8f63_4b0cec19fdb8_MD0005_00 Rabies is an invariably fatal viral disease; it is primarily acquired from a bite or exposure to saliva of a rabid animal. Post-exposure prophylaxis can prevent the development of rabies infection. This patient's history of bat contact would place him at risk for rabies infection; post-exposure prophylaxis should be considered. There are 2 forms of prophylaxis available: passive immunization with rabies immune globulin and active immunization with rabies vaccination. Most patients are diagnosed following an exposure (post-exposure prophylaxis). However, persons whose work/travel involves likely exposure to rabies should receive a pre-exposure prophylaxis course. In the unvaccinated patient, post-exposure prophylaxis consists of active immunization with rabies vaccine and passive immunization with rabies immunoglobulin. This patient received a rabies vaccination 1 year prior to the recent bat exposure. For patients who have been previously vaccinated, 2 doses of active immunization with rabies vaccine are recommended. Passive immunization with rabies immunoglobulin in addition to active vaccination (Choice B) is not recommended in previously vaccinated individuals; this can lead to the impairment of the strength and rapidity of the immune response. (Choices A and E) Observation and reassurance (inpatient/outpatient) are inadequate as active immunization is warranted in this situation. (Choice C) There is evidence that passive immunization with rabies immune globulin blunts the immune response to the vaccine. Further immune globulin should be avoided in previously vaccinated individuals as some amount of antibody is still circulating. Educational objective: Previously vaccinated individuals who are potentially re-exposed to rabies should receive only a booster course of rabies vaccine (2 doses). Those without a history of immunization require both immune globulin and a full vaccination series (4 doses). References: Use of a reduced (4-dose) vaccine schedule for postexposure prophylaxis to prevent human rabies (http://www.ncbi.nlm.nih.gov/pubmed/20300058) Rabies vaccines (http://www.ncbi.nlm.nih.gov/pubmed/20831913) Inhibition of immune responses against rabies virus by monoclonal antibodies directed against rabies virus antigens (http://www.ncbi.nlm.nih.gov/pubmed/1441731)

A 26-Year-Old Student Comes to the Emergency Department 10 Hours