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Thank you for raising the issue of abbreviations entering the virological lexicon which might give rise to confusion and misunderstanding. Over a decade has elapsed since our patient report was published and the source material is not retrievable. However, our recollection is the patient was discussed contemporaneously at the MDT and the viral aetiology, radiology findings and medical management determined and documented, from which the data was sourced for the 2008 report. Plausible as it may seem, it is not possible to test the veracity of the suggestion that the names ‘Jamestown Canyon’ and ‘John Cunningham’ might have been transposed during that MDT many years after the event, paper records are not kept indefinitely in NHS practice and ethics in medical publishing demands that patient identifiers are not described or retained in order to preserve anonymity. Perhaps the latter should have been considered over half a century ago when JC virus was first identified in the brain of the unfortunate patient after whom the eponymous pathogen was christened
(Padgett BL, Walker DL; et al. (1971). "Cultivation of papova-like virus from human brain with progressive multifocal leucoencephalopathy". Lancet. 1 (7712):
In their 2008 case report, Muqit, et al. describe a case of “presumptive Jamestown Canyon viral retinitis.”1
Jamestown Canyon virus is a mosquito-borne, single-stranded, ribonucleic acid (RNA) orthobunyavirus that is endemic throughout much of North America.2,3 Infection with Jamestown Canyon virus may be asymptomatic or may result in a general febrile illness, meningitis, and/or meningoencephalitis.2,3 Beyond the above case report by Muqit, et al.,1 and another review article referencing this case report,4 Jamestown Canyon virus has not been reported to cause retinitis or other ocular manifestations.
Upon close review of the case report by Muqit, et al.,1 we believe the authors are likely describing a case of John Cunningham (JC) virus (a ubiquitous, double-stranded, deoxyribonucleic acid [DNA] human polyomavirus known to cause progressive multifocal leukoencephalopathy [PML] among the immunocompromised)5-7 rather than Jamestown Canyon virus.
First, the case patient with viral retinitis had underlying human immunodeficiency virus (HIV) infection and a low CD4 lymphocyte count (240 cells/mm3), making him immunocompromised and susceptible to reactivation of the John Cunningham (JC) virus. Second, the case patient had magnetic resonance imaging (MRI) brain findings (i.e., asymmetric, predominantly posterior, confluent, subcortical white matter hyperintensities involving U-fibers) that are classic for John Cunningham (JC) virus-related PML.6,7 In fact,...
First, the case patient with viral retinitis had underlying human immunodeficiency virus (HIV) infection and a low CD4 lymphocyte count (240 cells/mm3), making him immunocompromised and susceptible to reactivation of the John Cunningham (JC) virus. Second, the case patient had magnetic resonance imaging (MRI) brain findings (i.e., asymmetric, predominantly posterior, confluent, subcortical white matter hyperintensities involving U-fibers) that are classic for John Cunningham (JC) virus-related PML.6,7 In fact, the authors claimed that the MRI brain findings were “confirmatory of the underlying diagnosis.”1 No MRI brain findings are classic or confirmatory for Jamestown Canyon virus infection. Third, the case patient’s cerebrospinal fluid was reportedly positive for viral DNA by polymerase chain reaction. This could only be possible for a DNA virus (i.e., John Cunningham (JC) virus) and not an RNA virus (i.e., Jamestown Canyon virus). Fourth, recovery of John Cunningham (JC) viral nucleic acid from ocular tissues of HIV-infected patients has been previously reported, so there is already precedent for this virus to infect the eye.8 Finally, the case patient had no known travel to or any mosquito exposure in North America, where Jamestown Canyon virus is endemic.2,3
Given John Cunningham (JC) and Jamestown Canyon viruses have different virology, epidemiology, and clinical manifestations, we believe the viruses were mistaken for one another because they share the same first letters of their words (i.e., J and C) and their abbreviations were likely confused. If our suspicion is correct, this case report highlights the possible dangers of abbreviations in medicine and the need to clearly define potentially confusing abbreviations in medical literature.
1. Muqit MM, Devonport H, Smith RA, Dhillon B. Presumptive Jamestown Canyon viral retinitis. Br J Ophthalmol. 2008 Dec;92(12):1599-600, 1695-6. doi: 10.1136/bjo.2007.132902. PMID: 19029162.
2. Coleman KJ, Chauhan L, Piquet AL, Tyler KL, Pastula DM. An Overview of Jamestown Canyon Virus Disease. Neurohospitalist. 2021 Jul;11(3):277-278. doi: 10.1177/19418744211005948. Epub 2021 Mar 29. PMID: 34163560; PMCID: PMC8182404.
3. Pastula DM, Hoang Johnson DK, White JL, Dupuis AP 2nd, Fischer M, Staples JE. Jamestown Canyon Virus Disease in the United States-2000-2013. Am J Trop Med Hyg. 2015 Aug;93(2):384-9. doi: 10.4269/ajtmh.15-0196. Epub 2015 Jun 1. PMID: 26033022; PMCID: PMC4530766.
4. Karesh JW, Mazzoli RA, Heintz SK. Ocular Manifestations of Mosquito-Transmitted Diseases. Mil Med. 2018 Mar 1;183(suppl_1):450-458. doi: 10.1093/milmed/usx183. PMID: 29635625.
5. Padgett BL, Walker DL, ZuRhein GM, Eckroade RJ, Dessel BH. Cultivation of papova-like virus from human brain with progressive multifocal leucoencephalopathy. Lancet. 1971 Jun 19;1(7712):1257-60. doi: 10.1016/s0140-6736(71)91777-6. PMID: 4104715.
6. Grebenciucova E, Berger JR. Progressive Multifocal Leukoencephalopathy. Neurol Clin. 2018 Nov;36(4):739-750. doi: 10.1016/j.ncl.2018.06.002. PMID: 30366552.
7. Pinto M, Dobson S. BK and JC virus: a review. J Infect. 2014 Jan;68 Suppl 1:S2-8. doi: 10.1016/j.jinf.2013.09.009. Epub 2013 Oct 8. PMID: 24119828.
8. Eberwein P, Hansen LL, Agostini HT. Genotypes of JC virus, DNA of cytomegalovirus, and proviral DNA of human immunodeficiency virus in eyes of acquired immunodeficiency syndrome patients. J Neurovirol. 2005 Feb;11(1):58-65. doi: 10.1080/13550280590900391. PMID: 15804960.