Review Question - QID 106724

This patient's presentation of fever, vesicoulcerative gingivostomatitis, and cervical lymphadenopathy is consistent with herpes simplex virus type 1 (HSV-1) infection.

HSV-1 can cause gingivostomatis (herpes labialis), keratoconjunctivitis, temporal lobe encephalitis, or meningitis. While HSV-1 typically presents "above the waist", HSV-2 is most commonly a sexually transmitted infection that manifests with genital vesicoulcerations. The initial HSV-1 infection is typically established through the mucosal epithelium in the mouth. The virus then travels retrogradely in the trigeminal ganglion, resulting in a life-long latent infection. Subsequent stress, in turn, reactivates the virus leading to the manifestation of cold sores. Cold sores, caused by reactivation of latent HSV-1 infection, should be differentiated from aphthous stomatitis (canker sores), which have an unknown cause and do not shed viral particles.

Usatine et al. review nongenital HSV-1 infections. HSV-1 is most commonly transmitted in childhood by saliva and/or respiratory secretions. Although diagnosis is typically apparent based on history and clinical presentation of grouped vescioulcerations on an erythematous base, it may be confirmed by viral culture, PCR, serology, direct fluorescence antibody testing, or Tzanck smear testing. Oral acyclovir is the first-line treatment for herpes gingivostomatitis and is also effective for prevention and treatment of subsequent recurrent cold sores.

Itzhaki discusses an interesting potential relationship between HSV-1 infection and Alzheimer's disease. The presence of HSV-1 in the brain of individuals with the apolipoprotein E type IV allele has been implicated as a major factor in the development of Alzheimer's disease. It is believed that the virus remains latent in the brain and reactivates under periods of stress, causing cumulative neuronal damage that ultimately leads to Alzheimer's disease.

Figure A shows vesicoulcerative gingivostomatitis in a patient with HSV-1 infection. Illustration A shows a reactivation cold sore in a patient with HSV-1. Illustration B shows the reactivation of HSV-1 in the trigeminal nerve.

Incorrect Answers:
Answer 2: HSV-2 is a sexually transmitted infection that presents with genital vesicles.
Answer 3: Epstein-Barr virus is the causative agent in infectious mononucleosis and is also involved in the development of oral hairy leukoplasia, Non-Hodgkin's lymphoma, Burkitt's lymphoma, and nasopharyngeal carcinoma.
Answer 4: Coxsackie A virus causes herpangina as well as hand, foot and mouth disease; herpangina is characterized by vesicles on the back of the throat, whereas the gingivostomatitis seen with HSV-1 presents with vesicoulcerations on the lips and interior of the mouth.
Answer 5: HHV-6 causes roseola infantum in infants.