Submitted by: Patricia Shea, DVM
J Am Vet Med Assoc 2017;251:935-940.
Use of poliglecaprone 25 for perineal urethrostomy in cats: 61 cases (2007-2013)
Frem DL, Hottinger HA, et al.
Perineal urethrostomy (PU) is a useful and frequently successful salvage surgery for male cats that have experienced repeat distal urethral obstruction secondary to lower urinary tract disease, urolithiasis, or following trauma. Crucial to the success of this procedure is meticulous, accurate apposition of the skin to the urethral mucosa, and this has been traditionally accomplished employing simple interrupted sutures of nonabsorbable suture material such as nylon or polypropylene, both of which have low tissue reactivity. However, removal of sutures in this anatomic area after healing has taken place, usually about 2 weeks postoperatively, is uncomfortable for the patient, and often requires heavy sedation or general anesthesia. Use of absorbable suture material, as long as it maintains sufficient tensile strength for the time required to heal the skin-mucosal closure, would obviate the need to remove sutures at the surgical site.
Poliglecaprone 25 is a synthetic monofilament absorbable suture impregnated with a broad spectrum antimicrobial (not antibiotic) substance. It is considered rapidly absorbable, being degraded by hydrolysis, in that it loses 2/3 of its tensile strength in vitro within 14 days, and is completely absorbed within 4 months. In this retrospective case series, the medical records of 61 cats who underwent PU surgery at a specialty practice between 2007 and 2012 in which poliglecaprone 25 was utilized to appose skin to the urethral mucosa, were reviewed. The authors hypothesized that short- and long-term complication rates following PU closure with poliglecaprone 25 would be comparable to those in which PU closure was performed using nonabsorbable or slowly absorbable (e.g., polydioxanone) suture. Short-term complications were defined as those occurring within the first two months following surgery, while long-term complications were those occurring > 2 months postoperatively.
Board-certified surgeons performed all of the procedures. All of the 61 study cats had at least one follow-up evaluation a minimum of 10 days after surgery. The 61 patients represented a variety of breeds; most were domestic shorthairs (45/61). Median age was 5.4 years, and median body weight was 5.6 kg. All study cats had undergone PU due to urethral obstruction, secondary to idiopathic lower urinary tract disease in the majority of cases (34/61; 56%). Urethral calculi (21/61; 34%) and urinary tract infection based on bacterial culture (10/61; 16%) were other presenting problems; four of the cats had both urethral calculi and bacterial urinary tract infection.
All patients had an Elizabethan collar in place during recovery. Three-quarters of the patients (46/61) had an indwelling urinary catheter placed after surgery, which remained in place for 0-4 days postoperatively. The range of hospitalization time for the patients following surgery was 1-6 days (mean, 2.6 days). Although the use of an indwelling urethral catheter following PU is controversial and considered in some studies to be conducive to formation of urethral stricture and promotion of ascending bacterial infection, in this study use of an indwelling urinary catheter after surgery was not significantly associated with development of postoperative complications.
Minor short-term complications, considered minor because they resolved with medical management only, developed in 11/61 (18%) of the patients, including incisional dehiscence due to self-trauma in two of the cats. Both cats experiencing incisional dehiscence had owner-reported self-trauma after removal of the Elizabethan collar. In both of these cases, rapid degradation of the suture material could not be ruled out, even though self-trauma involves significant mechanical stress and tissue irritation. The only major (requiring surgical revision) short-term complication developed in one cat who had a stricture at the PU site resulting in re-obstruction, and this cat was noted to have a large (1 cm diameter) mucosal defect at the time of surgery. Thirty-eight of the cats had long-term follow-up information available. Of these, 16 (42%) developed minor complications requiring medical management; in 15/16 cases the complications involved recurrent signs of lower urinary tract disease.
Overall, the short- and long-term postoperative complication rates in the study cats whose skin and urethral mucosa were apposed with poliglecaprone 25 were comparable to those in which nonabsorbable or slowly absorbable monofilament sutures were used. A prospective study in which several types of suture materials (poliglecaprone 25, polydioxanone, and nylon) and patterns (continuous versus interrupted) could be compared with respect to surgical outcomes for PU patients is recommended by the authors.
Danish J Archaeology 2018;7:241-254
Domestic cats (Felis catus) in Denmark have increased significantly in size since the Viking Age
Bitz-Thorsen J, Gotfredsen AB.
In the last year, the Danish tradition of hygge (pronounced “hoo-guh”) has become an international sensation and the subject of many books and Internet posts. Hygge involves the creation and enjoyment of simple pleasures and lifestyle activities that promote a feeling of coziness, warmth, relaxation, and conviviality. The peak season for hygge is late fall and winter in the Northern Hemisphere, the dark and cold days around the winter solstice.
Scandinavians, especially the Danes, have the reputation of being the happiest people on earth; the hygge tradition is part of this. And what could promote hygge more effectively than curling up with a favorite cat? The adult cat’s head is perfectly designed to nestle in the hollow of their human’s hand, but those cat heads are bigger nowadays. In this study of the skulls and bones of adult domestic cats excavated at archaeological sites in different parts of Denmark as well as modern skeletal remains (adult mixed breed cats, 1870-present), these researchers have demonstrated that modern cats are at least 16% bigger than their Viking Age (c.850-1050 CE) forebears. Most species of animals, including the dog, decreased in size with domestication compared to their wild ancestors, but not the cat.
Very small numbers of cats were present in pre-Viking Age Denmark; feline populations increased significantly by the Viking Age. In common with many early peoples, the Vikings initially valued cats as rodent catchers on ships and farms and a source of pelts, but by the late Middle Ages, they had become cherished and well-cared-for house pets. These Scandinavian cats were originally of Egyptian lineage. Although cat trading was illegal in Egypt by 1700 BCE, somehow cats with mitochondrial DNA of Egyptian lineage made their way to a Viking trading port on the Baltic Sea by the 7th century CE. Previous archaeological research has suggested that the Egyptians cultivated the human-cat bond in ways not pursued by other civilizations, producing cats that were more desirable because more socialized to humans, including farmers, sailors, and traders.
Femur length demonstrated the largest change over time (16%) while tooth size increased the least (5.5%), from Viking Age to modern times. From the Viking Age to the Medieval period, a gradual increase in femur length was observed, although there was overlap in measurements between the Viking Age and Medieval Age cat osteological materials. More modest increases in size were identified when comparing the femurs and teeth of post-Medieval cats with those of modern female cats; over this time span, femur length only increased 4%, while dental size increased 1.5%. Due to size variation observed in the bones of Viking and Medieval Age cats, it was likely that both sexes were represented, although it was not feasible to classify these ancient materials by sex. However, only female remains were used as modern comparisons, which means that the observed increases in skeletal size represent the minimum differences between the archaeological groups and modern cats.
Food availability was considered likely to be a major factor in the body size increase observed in the study. As cats transitioned from rodent hunters and pelt providers living commensally with human settlements or on ships to house pets with a subsidized lifestyle, more of the animal’s energy could be devoted to body growth rather than finding food. Genetic changes could also have played a role in the size increase, and additional studies would be required to establish this as a factor. In Denmark, ongoing interbreeding of domesticated cats with wild cats, as occurred in other parts of Europe, was very rare, as previous research has established that wild cats were no longer present in Denmark by the Early Roman Iron Age (1-100 CE). During the time of probable overlap between the presence of wild cats and domestic cats in Denmark (500 BCE-100 CE), both types of cat were present in very small numbers. Additional studies are required to determine if hybridization occurred involving these very early domestic cats and their wild counterparts.
Viruses 2018;10(8):433; https://doi.org/10.3390/v10080433
Potential therapeutic agents for feline calicivirus infection
Fumian TM, Enosi Tuipulotu D, et al.
Feline calicivirus (FCV), a small, single-stranded nonenveloped RNA virus, is one of the major etiologic agents of upper respiratory tract disease in cats. Viruses, principally FCV and the feline herpesvirus-1 (FHV-1), are responsible for approximately 80% of feline upper respiratory tract infections. Although vaccination against FCV and FHV-1 is widely employed as a core vaccination recommended for all cats, many kittens are exposed and infected prior to receiving a first vaccination. A chronic carrier state involving continuous shedding of FCV often ensues. Other, less common, syndromes associated with FCV infection in cats include polyarthritis, interstitial pneumonia, and nasal planum ulceration. In the last two decades a highly contagious, virulent strain of FCV has been identified (virulent systemic feline calicivirus; VS-FCV) which can cause severe clinical signs in infected patients, including edema of the face and paws, high fever, icterus, and hemorrhage, and involves mortality rates up to 50%.
In the case of FHV-1, infection is lifelong and the carrier state involves stress-triggered viral shedding. An antiviral agent, famciclovir, has proven to be useful in ameliorating clinical signs of FHV-1 associated ocular and/or upper respiratory infections. However, no direct-acting antivirals have been approved for treatment of FCV infections. In this study, 15 different compounds representing a variety of four different antiviral classes were tested in vitro for efficacy against FCV using protein and cell culture assays. The compounds were evaluated for their ability to inhibit FCV protease or polymerase, both of which are essential for viral replication. Famciclovir was among the 15 compounds tested for FCV antiviral activity; it demonstrated minimal anti-FCV activity even at high concentrations, and therefore is not a good option for treatment of FCV infections.
This study identified two in vitro assays that will allow the testing of agents that inhibit FCV protease or polymerase, and promote the development of FCV-targeted antivirals for clinical use. Some of the compounds that demonstrated inhibition of either FCV protease or polymerase, however, did not inhibit replication of this virus in cell culture, but two of the drugs did. These were nitazoxanide, a broad-spectrum antimicrobial licensed for treatment of gastroenteritis caused by Cryptosporidium parvum and Giardia intestinalis in humans, and a nucleoside analogue, 2′-C-methylcytidine (2CMC). They both emerged as potent inhibitors of FCV replication in cell culture, and have a synergistic effect when combined. Nitazoxanide has also been shown to eliminate shedding of Tritrichomonas foetus in cats, and has also been used in treating giardiasis and cryptosporidiosis in dogs.
However, 2CMC is known to have dose-related gastrointestinal side effects in humans, and this may limit its future clinical use in treating caliciviral infections. Nitazoxanide also is associated with concerns about gastrointestinal side effects (diarrhea and vomiting) in cats, and has a narrow in vitro therapeutic index. Given their synergistic inhibitory effect on FCV, the combination of these two agents might allow reduction in the effective concentration of nitazoxanide, thereby limiting its cytotoxic effects, while simultaneously improving drug efficacy. In the future, other potentially clinically useful anti-FCV antivirals may be identified using the in vitro assays developed in this research.