October 28, 2014 Grand Rounds

Case # 1. A 46/M with Burkitt's lymphoma, treatment-related myelodysplastic syndrome, s/p allogeneic stem cell transplantation 11 months prior to admission, who p/w intractable complex partial seizure and fever secondary to HHV-6 encephalitis

https://www.google.com/search?q=HHV-6&source=lnms&tbm=isch&sa=X&ei=natPVLyEMouvyQSZnYEo&ved=0CAkQ_AUoAg&biw=1920&bih=943#facrc=_&imgdii=_&imgrc=FqMPqQ62M74lAM%253A%3B9mqEToEvcY-DhM%3Bhttp%253A%252F%252Fupload.wikimedia.org%252Fwikipedia%252Fcommons%252Fc%252Fc8%252FHHV-6_inclusion_bodies.jpg%3Bhttp%253A%252F%252Fen.wikipedia.org%252Fwiki%252FHuman_herpesvirus_6%3B1350%3B900

1. The most consistently reported syndrome associated with HHV-6 infection among transplant patients is encephalitis. Patients can have mental status changes, behavioral disturbance, memory loss, and seizures. Other manifestations of HHV-6 in this patient population include: fever and rash, hepatitis, gastro-duodenitis, colitis, pneumonitis, and encephalitis.

2. A positive HHV-6 PCR from tissues can suggest the presence of disease. However, there is no single test that can differentiate HHV-6 causing disease from HHV-6 that is genomically integrated. A persistently high titer of HHV-6 PCR from tissues suggests genomically integrated HHV-6.

3. One study mentioned that even in asymptomatic transplant patients, HHV-6 can be detected in the CSF.

4. Treatment involves use of either ganciclovir, foscarnet, or cidofovir. There are no randomized controlled trials on antiviral efficacy. Reduction of a patient's immunosuppression is also recommended.Read here for more information.

Case # 2. A 31-day old infant presents with fever, rash, seizure, abdominal distension, and respiratory failure secondary to human parechovirus (HPeV) infection.

1. In an infant who presents with sepsis and CNS symptoms and the CSF is normal, think about HPeV infection. In one case series, CSF abnormalities in patients with HPeV infection were rare.

2. In adults, HPeV can present as fever, myalgia, and pharyngitis.

3. More on HPeV infection from blog entry dated July 22, 2014.