Lipopolysaccharide and toll-like receptor 4 in dogs with congenital portosystemic shunts

Outcome of dogs diagnosed with concurrent intrahepatic portosystemic shunts and vertebral lesions: six cases (2016-2022)

OBJECTIVES

To describe the clinical outcome of dogs diagnosed with concurrent discospondylitis/vertebral physitis and congenital intrahepatic portosystemic shunts.

MATERIALS AND METHODS

Medical records from two academic institutions were searched for dogs diagnosed with discospondylitis and/or vertebral physitis, and a concurrent intrahepatic portosystemic shunt. Dogs were excluded if they did not undergo attenuation of their shunt, did not have a single congenital intrahepatic shunt and did not have at least 90 days of follow-up.

RESULTS

Six dogs met the inclusion criteria and were included in the study. Discospondylitis alone was diagnosed in four dogs, vertebral physitis alone in one dog and both discospondylitis and vertebral physitis in one dog. Three dogs had a right divisional intrahepatic portosystemic shunt, and three dogs had a left divisional intrahepatic portosystemic shunt. Median duration of antimicrobial therapy was 112 days (range 14 to 240 days). Clinical resolution of discospondylitis and vertebral physitis was noted in all dogs. Endovascular attenuation was performed in all dogs a median of 82 days after presentation (range 1 to 317 days). No perioperative or postoperative complications occurred. All dogs were alive at the last available follow-up a median of 513 days after presentation (range 224 to 1504 days) and free of clinical signs associated with discospondylitis or vertebral physitis, as well as their portosystemic shunt.

CLINICAL SIGNIFICANCE

Dogs with intrahepatic portosystemic shunts may concurrently develop discospondylitis and vertebral physitis. With antimicrobial therapy and endovascular embolisation of their portosystemic shunt, all dogs in this study had a good outcome with clinical resolution of both disease processes. However, long-term follow-up was not obtained in all cases.

The role of TLR4-mediated MyD88/TRAF6/NF-κB signaling and pIgR intestinal expression in chicks during Salmonella enteritidis infection

To observe the effect of Salmonella enteritidis (SE)-induced inflammation on pIgR expression in jejunum and ileum. Salmonella enteritidis was orally administered to 7-day old Hyline chicks, which were killed after 1d,3d,7d and 14d. The mRNA expression of TLR4,MyD88,TRAF6,NF-κB, and pIgR was detected by real-time RT-PCR, and pIgR protein was detected by Western blotting. The TLR4 signaling pathway was activated, the mRNA expression of the pIgR in jejunum and ileum was increased, and pIgR protein in jejunum and ileum was up-regulated by SE. In SE-treated chicks,the pIgR in jejunum and ileum was up-regulated on mRNA,and protein level,associated with activation of the TRL4-mediated MyD88/TRAF6/NF-κB signaling pathway, which identifies this as a novel pIgR-related pathway to TLR4 activation.

Clinical response in dogs with acute hemorrhagic diarrhea syndrome following randomized probiotic treatment or fecal microbiota transplant

Probiotics and fecal microbiota transplants (FMTs) are two microbiome-targeted therapies that have been investigated for use in gastrointestinal diseases associated with dysbiosis. The aim of this study was to compare the effects of an oral multi-strain probiotic and enema-administered FMTs on clinical signs and serum lipopolysaccharide in dogs with acute hemorrhagic diarrhea syndrome (AHDS). A total of 18 client-owned dogs with a diagnosis of AHDS were enrolled in a randomized, blinded study at the time of hospital admission. The dogs were randomized into two groups: the probiotic group received a daily oral probiotic (200 × 10⁹ CFU/10kg q 24 h) for 14 days and a single sham enema; the FMT group received a single FMT via retention enema (10 mL/kg) and placebo oral capsule for 14 days. All dogs received concurrent standard-of-care therapy, including intravenous fluids and anti-emetics; no dogs received antimicrobials. The fecal score, disease severity scores, and serum lipopolysaccharide were measured on days 0, 3, and 14. Fourteen of eighteen enrolled dogs completed the study (n = 9 probiotics; n = 5 FMT). Lipopolysaccharide decreased on days 3 and 14 from baseline and correlated with fecal and disease severity scores. There was no difference in the duration or severity of clinical signs in dogs with AHDS following an enema-administered FMT compared to probiotic treatment. Further evaluation of serum lipopolysaccharide as a marker of disease severity and recovery is warranted.

Vasoactive intestinal peptide in canine portosystemic shunt in the absence of portal hypertension

Background

The congenital portosystemic shunt (PSS) is a common vascular anomaly in dogs. Vasoactive intestinal peptide (VIP) is produced in various organs (including the small intestine, large intestine, and pancreas), leading to abdominal vasodilation, increased blood flow, increased pancreatic blood flow, and promotion of pancreatic endocrine and exocrine secretions. However, there have been no reports on the concentration of VIP in the portal and peripheral veins in canine PSS.

Aim

The aim of this pilot study was to evaluate whether dogs with PSS have a different VIP concentration in their portal system in general.

Methods

Six dogs with an extrahepatic portosplenic shunt were included in the study. Blood samples were taken from the saphenous and portal veins during PSS ligation surgery with an amerid constrictor, to evaluate and compare the VIP concentration in both samples. VIP was measured using a commercial canine enzyme-linked immunosorbent assay kit.

Results

The breeds included Mongrels (n = 2), Norfolk Terriers (n = 1), Miniature Dachshunds (n = 1), and Maltese (n = 2), and their ages were 9.3 ± 6.5 months; the bodyweight was 3.3 ± 0.8 kg. The concentration of VIP in the saphenous vein was 17.75 ± 13.88 pg/ml; on the contrary, the concentration of VIP in the portal vein was 29.7 ± 20.29 pg/ml. There was no significant difference in the VIP concentration between veins.

Conclusion

There was no difference in the VIP concentration between the portal and saphenous veins, suggesting a non-association between VIP and the PSS, in the absence of portal hypertension.

Haematology and coagulation profiles in cats with congenital portosystemic shunts

Objectives The objectives of this study were, first, to report the haematological parameters and coagulation times for cats with a congenital portosystemic shunt (CPSS) and the influence of surgical shunt attenuation on these parameters; and, second, to identify any association between prolongation in coagulation profiles and incidence of perioperative haemorrhage. Methods This was a retrospective clinical study using client-owned cats with a CPSS. Signalment, shunt type (extra- or intrahepatic), degree of shunt attenuation (complete or partial), haematological parameters, prothrombin time (PT) and activated partial thromboplastin time (aPTT) test results, and occurrence of any perioperative clinical bleeding complications were recorded for cats undergoing surgical treatment of a CPSS at the Royal Veterinary College, UK, between 1994 and 2011. Results Forty-two cats were included. Thirty-six (85.7%) had an extrahepatic CPSS and six (14.3%) had an intrahepatic CPSS. Preoperatively, mean cell volume (MCV) and mean cell haemoglobin (MCH) were below the reference interval (RI) in 32 (76.2%) and 31 (73.8%) cats, respectively. Red blood cell count and mean cell haemoglobin concentration (MCHC) were above the RI in 10 (23.8%) and eight (19.1%) cats, respectively. Postoperatively, there were significant increases in haematocrit ( P = 0.044), MCV ( P = 0.008) and MCH ( P = 0.002). Despite the significant increase in MCV postoperatively, the median MCV postoperatively was below the RI, indicating persistence of microcytosis. Preoperatively, PT was above the upper RI in 14 cats (87.5%), and aPTT was above the upper RI in 11 cats (68.8%). No cat demonstrated a perioperative clinical bleeding complication. Conclusions and relevance Cats with a CPSS are likely to present with a microcytosis, but rarely present with anaemia, leukocytosis or thrombocytopenia. Surgical attenuation of the CPSS results in a significant increase in the HCT and MCV. Coagulation profiles in cats with a CPSS are likely to be prolonged, irrespective of shunt type, but do not appear to be associated with an increased risk of clinical bleeding.

Hepatic Encephalopathy

This article reviews hepatic encephalopathy (HE) in companion animals. Clinical signs and categories of hepatic disease likely to cause HE are discussed. Ammonia has a key role in pathogenesis and current concepts in body ammonia metabolism are reviewed. Inflammation and manganese accumulation are also thought to be important in pathogenesis. Treatment of HE in acute and chronic cases is discussed along with the rationale for current treatment recommendations. Potential avenues for new treatments and human treatments, which may be transferable to companion animals, are reviewed.