A 17-year-old boy is hospitalized with recent-onset insomnia, headaches, periodic agitation, and dysphagia. He is a high school student interested in becoming a veterinarian. He owns a snake, fish, and parrot and, about 4 weeks ago, went on a field trip to study bats in a cave. The patient has no known medical problems and is not taking any medications. He does not consume alcohol and has never used illicit drugs. Despite hospitalization and treatment, he develops painful spasms, progressive paralysis, and coma and dies. Which of the following interventions would have most likely prevented this student from developing this illness?

Question

A 17-year-old boy is hospitalized with recent-onset insomnia, headaches, periodic agitation, and dysphagia.  He is a high school student interested in becoming a veterinarian.  He owns a snake, fish, and parrot and, about 4 weeks ago, went on a field trip to study bats in a cave.  The patient has no known medical problems and is not taking any medications.  He does not consume alcohol and has never used illicit drugs.  Despite hospitalization and treatment, he develops painful spasms, progressive paralysis, and coma and dies.  Which of the following interventions would have most likely prevented this student from developing this illness?

Quizplus · Accepted Answer

11ec160b_3853_a5d3_9249_45cc569cae0b_MD0001_00 Restlessness, agitation, and dysphagia progressing to coma within weeks of exploring a bat cave is concerning for rabies encephalitis. Although bats (and, almost as commonly, raccoons) are among the main sources of rabies in the United States, many patients with bat rabies are not aware that they had been bitten. Once in a wound, the virus travels retrograde via peripheral nerves to the dorsal root ganglia and then to the brain, where replication occurs. The virus then spreads to other organs through neural pathways. Common manifestations include a nonspecific, flu-like prodrome followed by an acute neurologic syndrome with agitation, persistent fever, variable consciousness, and painful spasms with swallowing or inspiration (causing dysphagia, hydrophobia, and aerophobia). Generalized flaccid paralysis and coma ensue, with most patients dying within weeks. Prophylactic vaccination is recommended for individuals at high exposure risk (eg, veterinarians, cave explorers, laboratory workers handling infected tissues, travelers to countries where rabid dogs are prevalent). Postexposure prophylaxis (a medical emergency) generally includes rabies immune globulin and vaccination; it is not effective after symptom onset. The approved rabies vaccines consist of various rhabdovirus strains grown in tissue cell culture and inactivated by beta-propiolactone. (Choices A, C, and F) No antirabies drugs targeting specific viral pathways (eg, cellular entry) are available, and interferon is not used in rabies management. (Choice D) Some live attenuated rabies vaccines have been used in wild animal populations, but none are currently recommended in humans. The herpes zoster (shingles), varicella, and yellow fever vaccines are live attenuated. (Choice E) Toxoid (prepared from formalin- or heat-treated toxin) can induce humoral immunity against the corresponding toxin without producing serious toxic effects. However, rabies does not appear predominantly toxin-mediated. The tetanus-(reduced) diphtheria vaccine contains inactivated bacterial toxoids. Educational objective: In the United States, bats are the main source of rabies (only transmitted by mammals). Agitation and spasms progressing to coma within weeks of exposure is strongly suggestive of rabies encephalitis. Prophylactic vaccination is recommended for individuals at high risk for exposure to rabid animals or their tissues. The approved rabies vaccines consist of various rhabdovirus strains grown in tissue cell culture and then inactivated.

A 17-Year-Old Boy Is Hospitalized with Recent-Onset Insomnia, Headaches, Periodic