Rapid diagnosis of LaCrosse encephalitis: detection of specific immunoglobulin M in cerebrospinal fluid

Abstract

An immunoglobulin M (IgM) antibody capture enzyme immunoassay (MAC-EIA) was developed for the rapid and early diagnosis of LaCrosse (LAC) virus infections. The MAC-EIA was a sensitive and specific technique for the detection of IgM antibodies to LAC virus in cerebrospinal fluid specimens and in acute-phase serum specimens. In a retrospective study, cerebrospinal fluid and acute-phase serum paired samples from 108 patients were tested by the MAC-EIA and by an IgM immunofluorescence assay. The results were compared with the original diagnosis, which was made by using a variety of classical serological tests including serum neutralization, hemagglutination inhibition, and complement fixation. Thirty patients were confirmed as having LAC virus infections; of these, 30 (100%) were diagnosed as positive by serum MAC-EIA, and 27 (90%) were positive by cerebrospinal fluid MAC-EIA. The MAC-EIA was more sensitive than the IgM immunofluorescence assay. Two patients who were not previously confirmed as positive cases were diagnosed as having LAC virus infections by the MAC-EIA. One patient who was subsequently diagnosed as having a Jamestown Canyon virus infection and two patients who were previously infected with Jamestown Canyon virus were not falsely identified as having LAC virus infections by the MAC-EIA.

Canine LaCrosse Viral Meningoencephalomyelitis with Possible Public Health Implications

“…Serum canine distemper virus (CDV) titers were consistent with current vaccination. 16 Although enzyme-linked immunosorbent assay, IFA, serum neutralization, and complement fixation tests 15,19,20,24 are commercially available with anti-human LACV antibodies, a no such tests are available for anti-dog antibodies to LACV. Creation of an anti-dog antibody was attempted but not successful.…”

“…It had been suggested that LaCrosse viremias are transient and antibody titers and virus (as with other encephalitic viruses) may be sequestered in the CSF. 15,20,37,38 For this reason, cases positively diagnosed with LACV encephalitis by immunohistochemistry (IHC) have produced negative serologic results. 28 Corticosteroid therapy used in this case may have also had an effect on the attenuation of an antibody response.…”

Intrathecal immune response and virus-specific immunoglobulin M antibodies in laboratory diagnosis of acute poliomyelitis

“…Intrathecal production of virus-specific antibodies can also be used for the early diagnosis of viral infection in the central nervous system. Demonstration of a relative increase in total virus-specific antibody levels or the presence of virus-specific IgM-class antibodies in the cerebrospinal fluid (CSF) has been used to diagnose other viral infections in the central nervous system (2,3,6,8,12,13). A positive result is considered to document a causal relationship between infection and disease.…”