Early Neurophysiological Abnormalities in Suspected Acute Canine Polyradiculoneuropathy.

Acute canine polyradiculoneuritis (ACP) is a common peripheral neuropathy in dogs, and is generally self-limiting and benign. Electrodiagnostic (EDX) tests are typically performed after 7-10 days. Delaying the definitive diagnosis may hamper the treatment of other causes of acute weakness, which may require specific treatments and may carry different prognoses. This retrospective multicenter study aims to assess whether EDX performed within the first 6 days of clinical signs onset can detect alterations indicative of ACP, and aims to characterize the most prevalent alterations. A total of 71 dogs with suspected ACP were retrospectively analyzed and classified into two groups based on EDX timing: early group (EG, 1-6 days after symptom onset) and late group (LG, 7-15 days after symptom onset). In our study, no significant differences were found between the two groups in motor nerve conduction studies (MNCSs) and F-wave analysis, indicating that EDX is able to demonstrate abnormalities even in the first 6 days from onset. Although the LG showed significantly greater degrees of electromyographic (EMG) alterations compared to the EG, frequent muscle alterations were still observed in the EG group. These findings support the use of EDX in patients with suspected ACP within the first 6 days from the clinical onset. Prompt neurophysiological examinations for suspected ACP patients can be performed effectively and can help allow for early diagnosis and facilitate appropriate treatment.

Traumatic and iatrogenic sciatic nerve injury in 38 dogs and 10 cats: Clinical and electrodiagnostic findings.

BACKGROUND: Reports describing sciatic nerve injuries (SNI) and their outcome are scarce in veterinary medicine. HYPOTHESIS: Describe the causes of traumatic and iatrogenic SNI and evaluate which clinical and electrodiagnostic findings predict outcome. ANIMALS: Thirty-eight dogs and 10 cats with confirmed SNI referred for neurologic and electrodiagnostic evaluation. METHODS: Clinical and electrodiagnostic examination results, including electromyography (EMG), motor nerve conduction studies, muscle-evoked potential (MEP), F-waves, sensory nerve conduction studies, and cord dorsum potential (CDP), were retrospectively evaluated. Quality of life (QoL) was assessed based on owner interviews. RESULTS: Surgery (42%) and trauma (33%) were the most common causes of SNI; in dogs, 24% were caused by bites from wild boars. Ability to flex and extend the tarsus was significantly associated with positive outcome in dogs. Mean time from onset of clinical signs until electrodiagnostic evaluation was 67 ± 65 (range, 7-300) days and 65 ± 108 (range, 7-365) days for dogs and cats, respectively. A cut-off amplitude of 1.45 mV for compound motor action potentials (CMAP) was predictive of positive outcome in dogs (P = .01), with sensitivity of 58% and specificity of 100%. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinical motor function predicts recovery better than sensory function. Electrodiagnostic findings also may play a role in predicting the outcome of SNI. Application of the proposed CMAP cut-off amplitude may assist clinicians in shortening the time to reassessment or for earlier suggestion of salvage procedures. Owners perceived a good quality of life (QoL), even in cases of hindlimb amputation.

Case report: Sacral agenesis in two boxer dogs: clinical presentation, diagnostic investigations, and outcome.

Two boxer dogs from the same litter were presented at 3 months of age for urinary and fecal incontinence. Both dogs had an abnormal tail consisting of a small stump, an atonic anal sphincter, and absent perineal reflex and sensation. Neurological evaluation was indicative of a lesion of the cauda equina or sacral spinal cord. Radiology and CT scan of the spine displayed similar findings in the two dogs that were indicative of sacral agenesis. Indeed, they had 6 lumbar vertebrae followed by a lumbosacral transitional vertebra, lacking a complete spinous process, and a hypoplastic vertebra carrying 2 hypoplastic sacral transverse processes as the only remnant of the sacral bone. Caudal vertebrae were absent in one of the dogs. On MRI, one dog had a dural sac occupying the entire spinal canal and ending in a subfascial fat structure. In the other dog, the dural sac finished in an extracanalar, subfascial, well-defined cystic structure, communicating with the subarachnoid space, and consistent with a meningocele. Sacral agenesis-that is the partial or complete absence of the sacral bones-is a neural tube defect occasionally reported in humans with spina bifida occulta. Sacral agenesis has been described in human and veterinary medicine in association with conditions such as caudal regression syndrome, perosomus elumbis, and Currarino syndrome. These neural tube defects are caused by genetic and/or environmental factors. Despite thorough genetic investigation, no candidate variants in genes with known functional impact on bone development or sacral development could be found in the affected dogs. To the best of the authors' knowledge, this is the first report describing similar sacral agenesis in two related boxer dogs.

Clinical features of muscle stiffness in 37 dogs with concurrent naturally occurring hypercortisolism.

BACKGROUND: Severe muscle stiffness (SMS) in dogs with hypercortisolism (HC) is uncommon. OBJECTIVES: To evaluate signalment, presentation, treatments, and long-term outcomes of dogs with concurrent HC and SMS. ANIMALS: Thirty-seven dogs. METHODS: Medical records of dogs with HC and concurrent SMS were recruited from 10 institutions. Clinical information, test results, therapeutic responses, and survival times were reviewed. RESULTS: All 37 dogs with HC and SMS had pituitary-dependent hypercortisolism (PDH); 36/37 weighed <20 kg. Signs and test results were typical of PDH aside from SMS, initially diagnosed in all 4 limbs in 9, pelvic limbs of 22, and thoracic limbs of 6 dogs. Hypercortisolism and SMS were diagnosed together in 3 dogs; HC 1-36 months before SMS in 23; SMS 1-12 months before HC in 11. Mitotane or trilostane, given to control HC in 36/37 dogs, improved or resolved HC signs in 28; SMS did not resolve, remaining static or worsening in 31/36 dogs, mildly improving in 5/19 dogs given additional therapies. Progression of SMS included additional limbs in 10 dogs and the masticatory muscles of 2. The median survival time from diagnosis of SMS was 965 days (range, 8-1188). CONCLUSIONS AND CLINICAL IMPORTANCE: Concurrent SMS and HC is uncommon, possibly affecting only dogs with PDH. Development of SMS might occur before or after diagnosis of HC. Apart from SMS, the clinical picture and survival time of these dogs seem indistinguishable from those of dogs with HC in general. However, while muscle weakness usually resolves with HC treatment SMS does not.

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

Recent work identified anti-GM2 and anti-GalNAc-GD1a IgG ganglioside antibodies as biomarkers in dogs clinically diagnosed with acute canine polyradiculoneuritis, in turn considered a canine equivalent of Guillain-Barré syndrome. This study aims to investigate the serum prevalence of similar antibodies in cats clinically diagnosed with immune-mediated polyneuropathies. The sera from 41 cats clinically diagnosed with immune-mediated polyneuropathies (IPN), 9 cats with other neurological or neuromuscular disorders (ONM) and 46 neurologically normal cats (CTRL) were examined for the presence of IgG antibodies against glycolipids GM1, GM2, GD1a, GD1b, GalNAc-GD1a, GA1, SGPG, LM1, galactocerebroside and sulphatide. A total of 29/41 IPN-cats had either anti-GM2 or anti-GalNAc-GD1a IgG antibodies, with 24/29 cats having both. Direct comparison of anti-GM2 (sensitivity: 70.7%; specificity: 78.2%) and anti-GalNAc-GD1a (sensitivity: 70.7%; specificity: 70.9%) antibodies narrowly showed anti-GM2 IgG antibodies to be the better marker for identifying IPN-cats when compared to the combined ONM and CTRL groups (P = .049). Anti-GA1 and/or anti-sulphatide IgG antibodies were ubiquitously present across all sample groups, whereas antibodies against GM1, GD1a, GD1b, SGPG, LM1 and galactocerebroside were overall only rarely observed. Anti-GM2 and anti-GalNAc-GD1a IgG antibodies may serve as serum biomarkers for immune-mediated polyneuropathies in cats, as previously observed in dogs and humans.

Biopsy Characteristics, Subtypes, and Prognostic Features in 107 Cases of Feline Presumed Immune-Mediated Polyneuropathy.

Inflammatory polyradiculoneuropathy (IMPN) is one of the causes of sudden onset of neuromuscular signs such as para-/tetraparesis in young cats. Even though most cases have a favorable outcome, persistent deficits, relapses, and progressive courses are occasionally seen. As clinical presentation does not always appear to predict outcome and risk of recurrence, this study was initiated to screen for prognostic biopsy findings in a large cohort of histologically confirmed IMPN cases with clinical follow-up. In total, nerve and muscle specimens of 107 cats with biopsy diagnosis of presumed autoreactive inflammatory polyneuropathy and 22 control cases were reviewed by two blinded raters for a set of 36 histological parameters. To identify patterns and subtypes of IMPN, hierarchical k-means clustering of 33 histologic variables was performed. Then, the impact of histological parameters on IMPN outcome was evaluated via an univariate analysis to identify variables for the final multivariate model. The data on immediate outcome and follow-up were collected from submitting neurologists using a purpose-designed questionnaire. Hierarchical k-means clustering sorted the tissues into 4 main categories: cluster 1 (44/129) represents a purely inflammatory IMPN picture, whereas cluster 2 (47/129) was accompanied by demyelinating features and cluster 3 (16/129) by Wallerian degeneration. Cluster 4 (22/129) reflects normal tissues from non-neuropathic control cats. Returned questionnaires provided detailed information on outcome in 63 animals. They were categorized into recovered and non-recovered. Thereby, fiber-invasive infiltrates by mononuclear cells and mild fiber loss in intramuscular nerve branches correlated with higher probabilities of recovery. Remyelination in semithin sections, on the other hand, is correlated with a less favorable outcome. Animals grouping in cluster 1 had a tendency to a higher probability of recovery compared to other clusters. In conclusion, diagnosis of feline IMPN from nerve and muscle biopsies allowed for the identification of histologic features that were positively or negatively correlated with outcome.

Clinical Course and Diagnostic Findings of Biopsy Controlled Presumed Immune-Mediated Polyneuropathy in 70 European Cats.

There is a paucity of information on the clinical course and outcome of young cats with polyneuropathy. The aim of the study was to describe the clinical features, diagnostic investigations, and outcome of a large cohort of cats with inflammatory polyneuropathy from several European countries. Seventy cats with inflammatory infiltrates in intramuscular nerves and/or peripheral nerve biopsies were retrospectively included. Information from medical records and follow up were acquired via questionnaires filled by veterinary neurologists who had submitted muscle and nerve biopsies (2011-2019). Median age at onset was 10 months (range: 4-120 months). The most common breed was British short hair (25.7%), followed by Domestic short hair (24.3%), Bengal cat (11.4%), Maine Coon (8.6%) and Persian cat (5.7%), and 14 other breeds. Male cats were predominantly affected (64.3%). Clinical signs were weakness (98.6%) and tetraparesis (75.7%) in association with decreased withdrawal reflexes (83.6%) and, less commonly, cranial nerve signs (17.1%), spinal pain/hyperesthesia (12.9%), and micturition/defecation problems (14.3%). Onset was sudden (30.1%) or insidious (69.1%), and an initial progressive phase was reported in 74.3%. Characteristic findings on electrodiagnostic examination were presence of generalized spontaneous electric muscle activity (89.6%), decreased motor nerve conduction velocity (52.3%), abnormal F-wave studies (72.4%), pattern of temporal dispersion (26.1%) and unremarkable sensory tests. The clinical course was mainly described as remittent (49.2%) or remittent-relapsing (34.9%), while stagnation, progressive course or waxing and waning were less frequently reported. Relapses were common and occurred in 35.7% of the cats' population. An overall favorable outcome was reported in 79.4% of patients. In conclusion, young age at the time of diagnosis and sudden onset of clinical signs were significantly associated with recovery (p < 0.05). Clinical and electrodiagnostic features and the remittent-relapsing clinical course resembles juvenile chronic inflammatory demyelinating polyneuropathy (CIDP), as seen in human (children/adolescents), in many aspects.

Use of Electrodiagnostics in the Diagnosis and Follow-Up of Brachial Plexus Syndrome in a Calf.

Electrodiagnostic testing by using electromyography (EMG) and nerve conduction studies (NCS) is essential in the evaluation of patients with traumatic brachial plexus injury as it facilitates the localization of the lesion and the prognosis. In this case report, we present a long-term electrodiagnostic follow-up of a 5-day-old female Holstein calf with brachial plexus syndrome. Electrodiagnostic studies were carried out at 2 weeks, 5 weeks, 7 months and 12 months after admission. Initially, EMG confirmed the damage to the brachial plexus, potentially indicating a condition of neurotmesis or axonotmesis. However, motor NCS and the repeated electrodiagnostic follow-up, along with the evolution of the clinical signs, allowed a more favorable diagnosis of axonotmesis to be made. In fact, EMG showed a slow but gradual reduction and finally the disappearance of spontaneous pathological activity, while motor NCS revealed an increase in the amplitude and areas of the compound muscle action potentials. The animal was deemed fully recovered 12 months after admission. To the authors' knowledge, this is the first report on the use of motor NCS in bovine medicine and it demonstrates that electrodiagnostics represent a useful and practical tool for the evaluation and prognosis of brachial plexus injury cases in cattle.

A homozygous missense variant in laminin subunit beta 1 as candidate causal mutation of hemifacial microsomia in Romagnola cattle.

Hemifacial microsomia (HFM) was diagnosed in a 9-day-old Romagnola calf. The condition was characterized by microtia of the left ear, anotia of the right ear, asymmetry of the face, and deafness. Magnetic resonance imaging revealed agenesis of the right pinna and both tympanic bullae, asymmetry of the temporal bones and temporomandibular joints, and right pontine meningocele. Brainstem auditory evoked responses confirmed the impaired auditory capacity. At gross post mortem examination, there was agenesis and hypoplasia of the right and the left external ear, respectively. No histological abnormalities were detected in the inner ears. A trio whole-genome sequencing approach was carried out and identified a private homozygous missense variant in LAMB1 affecting a conserved residue (p.Arg668Cys). Genotyping of 221 Romagnola bulls revealed a carrier prevalence <2%. This represents a report of a LAMB1-related autosomal recessive inherited disorder in domestic animals and adds LAMB1 to the candidate genes for HFM.

Clinical, Electrodiagnostic Findings and Quality of Life of Dogs and Cats with Brachial Plexus Injury.

Brachial plexus injury (BPI) represents a common consequence of road traffic accidents in humans and small animals. In humans, neuropathic pain is a common symptom after BPI. The aim of the study was to describe the clinical signs, the electrodiagnostic findings, the outcome and the quality of life (QoL) of a cohort of dogs and cats with BPI. Clinical records of 40 dogs and 26 cats with BPI were retrospectively reviewed. Specific attention was put on the evaluation of electrodiagnostic findings (35/40 dogs; 14/26 cats) and telephonic interview results (26/40 dogs; 18/26 cats). The most common neurological condition was the inability to bear weight and sensory deficits on the affected limb. Radial and ulnar motor nerve conduction studies (MNCSs) were absent respectively in 47% (radial) and 62% (ulnar) of dogs and 57% (radial) and 57% (ulnar) of cats. The absence of radial (p = 0.003) and ulnar (p = 0.007) MNCSs in dogs and ulnar MNCSs in cats (p = 0.02) was significantly associated to the amputation of the affected limb. The owners described signs of pain/discomfort in 73% of dogs and 56% of cats. This is the first report suggesting that neuropathic pain/discomfort should be adequately considered in order to improve the QoL.

The acoustically evoked short latency negative response (ASNR) in a unilaterally deaf cat with histologically-confirmed cochleosaccular degeneration.

BACKGROUND: A negative potential is occasionally recorded in humans and animals with profound deafness during brainstem auditory evoked potential (BAER) tests if loud intensities are used. This acoustically evoked short latency negative response (ASNR) is hypothesized to be of saccular origin. The sensitivity to sound of vestibular end organs is also used to produce vestibular evoked myogenic potentials (VEMP), a test that evaluates vestibular function. The same saccular origin is accepted also for VEMP. CASE PRESENTATION: A neutered male white domestic short hair cat presented with profound deafness and an ASNR in the left ear during BAER test performed when he was 8 months old. BAER tracings were substantially unchanged at the age of 12 years, immediately before euthanasia that was requested by the owner for the presence of an unrelated neoplastic disorder. The cat underwent a complete post-mortem necropsy including histopathology of the middle and inner ears. Histopathologic results confirmed the presence of a cochleosaccular degeneration of the left ear while the cochlea and sacculus of the right ear and the utriculus and semicircular canals of both ears were histologically normal. CONCLUSIONS: This case report describes the auditory and histopathologic findings of a cat that showed an ASNR during BAER test despite the presence of cochleosaccular deafness. These results confirm that a saccular origin for the ASNR in this case, and in general in cats and dogs with congenital deafness associated with white pigmentation, is improbable. The hypothesis that the sacculus is the vestibular end organ responsible for the generation of the ASNR and VEMP in humans comes mainly from animal studies. The findings in this report may change the clinical interpretation of the results of BAER and VEMP not only in companion animals, but in humans as well.

Sciatic neuropathy in an acromegalic cat without concurrent diabetes mellitus.

CASE SUMMARY: A 17-year-old neutered male European Shorthair cat was presented owing to an inability to jump and respiratory stridor. The owner did not report any other clinical signs. On physical examination, the main findings were plantigrade stance, broad facial features and inspiratory stridor. Neurological examination revealed posterior paraparesis, hypotonia and right hindlimb muscle atrophy. Laboratory findings were unremarkable and glycaemia was normal. Serum insulin-like growth factor 1 concentration was elevated (>1000 ng/ml). A total body CT scan showed an enlarged pituitary gland, thickening of the nasal turbinates and an L7-S1 right foraminal stenosis. Electrodiagnostic testing confirmed the presence of a neuropathy affecting both sciatic nerves. The cat was treated with gabapentin only and was still alive and euglycaemic 16 months after the diagnosis. RELEVANCE AND NOVEL INFORMATION: This case describes for the first time sciatic neuropathy, an occasional complication of acromegaly in people, as a possible clinical presentation in acromegalic cats without concurrent diabetes mellitus.

IMAGING DIAGNOSIS-ULTRASONOGRAPHIC APPEARANCE OF SKELETAL MUSCLE METASTASES IN A DOG WITH HEMANGIOSARCOMA.

A 13-year-old spayed female German shepherd dog was presented for acute onset of lethargy, anorexia, and disseminated erythematous skin lesions. Thoracic radiographs and abdominal ultrasonographic findings were consistent with metastatic hemangiosarcoma. Multiple, ill-defined, irregularly shaped hypoechoic nodules were also detected within the thoracic and abdominal wall. Hemangiosarcoma metastases to the skeletal muscle were confirmed based on histopathological examination. Multivisceral involvement was also confirmed by necropsy. Metastatic neoplasia should be considered as a differential diagnosis for dogs with ill-defined, irregular, hypoechoic, intramuscular nodules.

Emphysematous pyelitis and cystitis associated with vesicoureteral reflux in a diabetic dog.

A 12-year-old female dog with a 3-month history of poor response to diabetes treatment had an acute worsening of symptoms, including weakness and blindness. The dog had elevated blood glucose, alkaline phosphatase and urea concentration, hyposthenuria, glycosuria, hematuria, and pyuria. Escherichia coli was isolated from the urine. Radiographs and ultrasound examination showed that the dog had unilateral emphysematous pyelitis and concurrent cystitis associated with vesicoureteral reflux.

Pyélite emphysémateuse et cystite associées au reflux vésico-urétéral chez une chienne diabétique. Une chienne âgée de 12 ans avec une anamnèse de 3 mois de mauvaise réponse au traitement du diabète a présenté un aggravement aigu des symptômes, y compris de la faiblesse et de la cécité. La chienne avait une glycémie élevée, ainsi que des concentrations sériques élevées de la phosphatase alcaline et d'urée, de l'hyposthénurie, de la glycosurie, de l'hématurie et de la pyurie. Escherichia coli a été isolé de l'urine. Des radiographies et des échographies ont montré que la chienne était atteinte de pyélite emphysémateuse unilatérale et de cystite concomitante associées au reflux vésico-urétéral.(Traduit par Isabelle Vallières).

Characterization of a spontaneous novel mutation in the NPC2 gene in a cat affected by Niemann Pick type C disease.

Niemann-Pick C disease (NPC) is an autosomal recessive lysosomal storage disorder characterized by accumulation of unesterified cholesterol and other lipids within the lysosomes due to mutation in NPC1 or NPC2 genes. A feline model of NPC carrying a mutation in NPC1 gene has been previously described. We have identified two kittens affected by NPC disease due to a mutation in NPC2 gene. They manifested with tremors at the age of 3 months, which progressed to dystonia and severe ataxia. At 6 months of age cat 2 was unable to stand without assistance and had bilaterally reduced menace response. It died at the age of 10 months. Post-mortem histological analysis of the brain showed the presence of neurons with cytoplasmic swelling and vacuoles, gliosis of the substantia nigra and degeneration of the white matter. Spheroids with accumulation of ubiquitinated aggregates were prominent in the cerebellar cortex. Purkinje cells were markedly reduced in number and they showed prominent intracytoplasmic storage. Scattered perivascular aggregates of lymphocytes and microglial cells proliferation were present in the thalamus and midbrain. Proliferation of Bergmann glia was also observed. In the liver, hepatocytes were swollen because of accumulation of small vacuoles and foamy Kupffer cells were also detected. Foamy macrophages were observed within the pulmonary interstitium and alveoli as well. At 9 months cat 1 was unable to walk, developed seizures and it was euthanized at 21 months. Filipin staining of cultured fibroblasts showed massive storage of unesterified cholesterol. Molecular analysis of NPC1 and NPC2 genes showed the presence of a homozygous intronic mutation (c.82+5G>A) in the NPC2 gene. The subsequent analysis of the mRNA showed that the mutation causes the retention of 105 bp in the mature mRNA, which leads to the in frame insertion of 35 amino acids between residues 28 and 29 of NPC2 protein (p.G28_S29ins35).

Dermatomyositis-like disease in a Rottweiler.

BACKGROUND: Canine dermatomyositis is a hereditary disease described in collies and Shetland sheep dogs and their cross-breeds. A similar disease, called dermatomyositis-like disease, has been described occasionally in other breeds but never in the Rottweiler. HYPOTHESIS/OBJECTIVES: We report on the clinicopathological findings associated with dermatomyositis-like disease in a Rottweiler. ANIMAL: A 7-month-old female Rottweiler was referred for dermatological abnormalities, regurgitation and weakness. Cutaneous abnormalities included alopecia, crusting and scaling on the inner surface of the pinnae, the tip of the tail, periorbital and perilabial skin. The dog also presented onychogryphosis and onychalgia. METHODS: Complete blood count, serum biochemistry panel, thoracic radiographs, electromyography, nerve-conduction studies and skin and muscle biopsies were performed. RESULTS: Megaoesophagus, pneumonia, ischaemic dermatopathy and generalized myositis were documented. The final diagnosis was dermatomyositis-like disease. CONCLUSIONS AND CLINICAL IMPORTANCE: This is the first report of dermatomyositis-like disease in a Rottweiler.

Use of aglepristone for the treatment of P4 induced insulin resistance in dogs.

Insulin resistance (IR) in dogs is suspected when hyperglycemia is present despite administration of insulin doses greater than 1.0 to 1.5 UI/kg. IR is caused by increases in counter regulatory hormones concentrations (glucagon, glucocorticoids, catecholamines and growth hormone). This study was conducted to investigate the use of aglepristone (RU 46534), a P4 receptor antagonist, for the treatment of IR diabetes mellitus in bitches during the luteal phase. All animals were treated with porcine insulin zinc suspension (Caninsulin) and aglepristone (Alizin) 10 mg/kg subcutaneously at day 1, 2, 9 and 17 from diagnosis. At day 5, no significant variation in glycemia was shown. At day 12 and 20, serum glucose concentrations were significant lower (p < 0.05). From day 12 the insulin dose was reduced to 0.8 IU BID. Insulin was reduced in the following weeks and glycemia was controlled.

Anti-GM2 ganglioside antibodies are a biomarker for acute canine polyradiculoneuritis.

Acute canine polyradiculoneuritis (ACP) is considered to be the canine equivalent of the human peripheral nerve disorder Guillain-Barré syndrome (GBS); an aetiological relationship, however, remains to be demonstrated. In GBS, anti-glycolipid antibodies (Abs) are considered as important disease mediators. To address the possibility of common Ab biomarkers, the sera of 25 ACP dogs, 19 non-neurological, and 15 epileptic control dogs were screened for IgG Abs to 10 glycolipids and their 1 : 1 heteromeric complexes using combinatorial glycoarrays. Anti-GM2 ganglioside Abs were detected in 14/25 ACP dogs, and anti-GA1 Abs in one further dog. All controls except for one were negative for anti-glycolipid Abs. In this cohort of cases and controls, the glycoarray screen reached a diagnostic sensitivity of 60% and a specificity of 97%; a lower sensitivity (32%) was reported using a conventional glycolipid ELISA. To address the possible pathogenic role for anti-GM2 Abs in ACP, we identified GM2 in canine sciatic nerve by both mass spectrometry and thin layer chromatography overlay. In immunohistological studies, GM2 was localized predominantly to the abaxonal Schwann cell membrane. The presence of anti-GM2 Abs in ACP suggests that it may share a similar pathophysiology with GBS, for which it could thus be considered a naturally occurring animal model.

Changes in electromyography and F wave responses in two cats with presumed local tetanus: implications for diagnosis and prognosis.

Two cases of focal tetanus in the cat are described. Clinical findings included severe muscular spasms of the pelvic limbs in one cat, and involvement of the thoracic limbs and muscles of the neck and face in the other. Electromyography in both cats showed spontaneous activity characterised by the presence of motor unit potentials. F waves, never previously reported in focal tetanus in animals, showed significantly increased F/M amplitude ratio in both cats and increased F wave duration in one cat. The electrodiagnostic findings provided relevant diagnostic and, possibly, prognostic information.

Electrodiagnostic examination of the tibial nerve in clinically normal ferrets.

Tibial nerves of 10 normal domestic ferrets (Mustela putorius furo) were evaluated by means of electrodiagnostic tests: motor nerve conduction studies (MNCSs), supramaximal repetitive nerve stimulation (SRNS), F waves, and cord dorsum potentials (CDPs). Values of conduction velocity, proximal and distal compound muscular action potentials, and amplitudes of MNCS were, respectively, 63.25 +/- 7.56 m/sec, 10.79 +/- 2.75 mV, and 13.02 +/- 3.41 mV. Mean decrements in amplitude and area of compound muscular action potentials of wave 9 with low frequency SRNS were 0.3 +/- 3.83% and 0.1 +/- 3.51%. The minimum latency of the F waves and the F ratio were, respectively, 8.49 +/- 0.65 ms and 1.92 +/- 0.17. Onset latency of CDP was 1.99 +/- 0.03 ms. These tests may help in diagnosing neuromuscular disorders and in better characterizing the hindlimb paresis reported in many ferrets with systemic illnesses.