Serum anti‐GM2 and anti‐GalNAc‐GD1a IgG antibodies are biomarkers for acute canine polyradiculoneuritis

Abstract

Objectives A previous single‐country pilot study indicated serum anti‐GM2 and anti‐GA1 anti‐glycolipid antibodies as potential biomarkers for acute canine polyradiculoneuritis. This study aims to validate these findings in a large geographically heterogenous cohort. Materials and Methods Sera from 175 dogs clinically diagnosed with acute canine polyradiculoneuritis, 112 dogs with other peripheral nerve, cranial nerve or neuromuscular disorders and 226 neurologically normal dogs were screened for anti‐glycolipid antibodies against 11 common glycolipid targets to determine the immunoglobulin G anti‐glycolipid antibodies with the highest combined sensitivity and specificity for acute canine polyradiculoneuritis. Results Anti‐GM2 anti‐glycolipid antibodies reached the highest combined sensitivity and specificity (sensitivity: 65.1%, 95% confidence interval 57.6 to 72.2%; specificity: 90.2%, 95% confidence interval 83.1 to 95.0%), followed by anti‐GalNAc‐GD1a anti‐glycolipid antibodies (sensitivity: 61.7%, 95% confidence interval 54.1 to 68.9%; specificity: 89.3%, 95% confidence interval 82.0 to 94.3%) and these anti‐glycolipid antibodies were frequently present concomitantly. Anti‐GA1 anti‐glycolipid antibodies were detected in both acute canine polyradiculoneuritis and control animals. Both for anti‐GM2 and anti‐GalNAc‐GD1a anti‐glycolipid antibodies, sex was found a significantly associated factor with a female to male odds ratio of 2.55 (1.27 to 5.31) and 3.00 (1.22 to 7.89), respectively. Anti‐GalNAc‐GD1a anti‐glycolipid antibodies were more commonly observed in dogs unable to walk (OR 4.56, 1.56 to 14.87). Clinical Significance Anti‐GM2 and anti‐GalNAc‐GD1a immunoglobulin G anti‐glycolipid antibodies represent serum biomarkers for acute canine polyradiculoneuritis.

Serum anti‐GM2 and anti‐GalNAc‐GD1a ganglioside IgG antibodies are biomarkers for immune‐mediated polyneuropathies in cats

“…Interestingly, nearly two-thirds of the IPN-cats had a disease onset in the autumn (25%) and winter (40%) months, similar to observed in previous studies on immune-mediated peripheral neuropathies (ACP) in dogs. 14,27 The IPN-cats in this study possessed serum anti-GM2 and anti-GalNAc-GD1a antibodies as the most distinct AGAb marker, highly similar to our previous findings in ACP-dogs. 14 Antibodies to both these targets reached a higher sensitivity, yet slightly lower specificity, when compared to the ACP-dogs.…”

“…14,27 The IPN-cats in this study possessed serum anti-GM2 and anti-GalNAc-GD1a antibodies as the most distinct AGAb marker, highly similar to our previous findings in ACP-dogs. 14 Antibodies to both these targets reached a higher sensitivity, yet slightly lower specificity, when compared to the ACP-dogs. Also as seen in ACP-dogs, many IPN-cats possessed both anti-GM2 and anti-GalNAc-GD1a AGAbs, yet with lower binding levels for the latter.…”

“…Albeit slightly higher in frequency, this observation corresponds to our and other previous observations in neurologically normal dogs and humans, in which AGAbs are also occasionally found. 14,32 Many AGAbs exist in the normal natural antibody repertoire, notably but not restricted to anti-GA1 and -sulphatide antibodies as reported herein for cats. It is therefore imperative to carefully consider assay thresholds, choices of antigens and disease control groups when conducting studies on AGAbs.…”

“…In ACP, initially in a pilot study and latterly in a larger international cohort, we observed a high prevalence of serum anti-GM2 and anti-GalNAc-GD1a antibodies. 14,15 Herein, we investigated cats clinically diagnosed with immune-mediated polyneuropathies (IPN) in comparison to neurological and non-neurological control groups for the prevalence of similar serum AGAbs.…”

“…Knowledge of human disease biomarkers in GBS led us to first investigate dogs clinically diagnosed with acute canine polyradiculoneuritis (ACP), a canine equivalent to GBS, for similar AGAbs. In ACP, initially in a pilot study and latterly in a larger international cohort, we observed a high prevalence of serum anti‐GM2 and anti‐GalNAc‐GD1a antibodies 14,15 . Herein, we investigated cats clinically diagnosed with immune‐mediated polyneuropathies (IPN) in comparison to neurological and non‐neurological control groups for the prevalence of similar serum AGAbs.…”