Gastric granulomatous cryptococcosis mimicking gastric carcinoma in a dog.

An ulcerated lesion resembling a tumour in the lesser curvature of the stomach of a 3-year-old male Dobermann pinscher was found to be caused by Cryptococcus neoformans. The dog had been vomiting for two months and had slight leucocytosis and anaemia. Biopsies of the ulcerated lesion revealed granulomatous inflammation and many cryptococci, which were particularly prominent in PAS and mucicarmine stained sections. No other lesions were found at necropsy.     

Mycobacterium ulcerans infections in two horses in south-eastern Australia

Two horses were diagnosed as having Mycobacterium ulcerans infections. The first was a 21-year-old Quarterhorse-cross mare living in Mallacoota (a coastal town near the border of New South Wales and Victoria, Australia) that presented with lichenification, hair-loss and oedema on a fetlock, which subsequently ulcerated, as well as a non-healing ulcer on the wither. The second horse was a 32 year-old Standardbred gelding from Nicholson, near Bairnsdale, Victoria, that had an ulcerated lesion on its caudal thigh. Histologically, there were characteristic changes seen with M. ulcerans infections in other species, including extensive necrosis without associated granulomatous inflammation. The organisms were seen in Ziehl-Neelsen-stained smears or sections of the lesions from both horses and were isolated in culture from the first horse. A definitive diagnosis was provided by real-time polymerase chain reaction targeting the M. ulcerans-specific insertion sequence, IS2404. Delayed identification of the infectious agent in the first case led to the use of suboptimal antimicrobial therapy, resulting in failure to control the infection and the horse was subsequently euthanased. The second horse was successfully treated following surgical debulking of the centre of the lesion and one session of aggressive cryosurgery. Mycobacterium ulcerans should be considered in the differential diagnosis of unexplained lichenification with oedematous and ulcerated skin lesions in horses living in regions where this organism is endemic.     

Congenital tremor in Holstein Friesian‐cattle

Summary

In a female family line of Holstein‐Friesian cattle a series of trembling calves was born within a period of ten years. All trembling animals were male; female calves appeared normal At necropsy of one calf severe degenerative lesions of spinal cord and brain white matter were observed Both myelin and axons were lost and some macrophages occurred within digestion chambers. Obviously degenerated neurones were not found The lesion was interpreted as a single recessive sex‐linked hereditary trait.     

Mortierella wolfii keratomycosis in a horse

Purpose To describe a case of superficial keratomycosis caused by Mortierella wolfii (M. wolfii) in a horse. Methods A thoroughbred filly was presented with painful right eye of 2 days’ duration. A superficial corneal ulcer was observed ventrally together with multifocal punctuate opacities axially. Samples were collected by swabbing and scraping the ulcerated lesion and submitted for microbiologic and cytologic examination. Results Microscopic evaluation of debrided corneal tissue revealed the presence of nonseptate fungal hyphae, and culture of a corneal swab yielded fungal growth. Medical treatment with topical antifungal, antibiotic and autogenous serum and systemic anti‐inflammatory resolved the problem within 2 weeks. Conclusions Cytologic evaluation of a corneal scraping was useful to make a clinical diagnosis of keratomycosis. Based on the mycological characteristics, the fungus isolated from the corneal lesion was identified as M. wolfii. To the authors’ knowledge, this is the first case report of equine keratomycosis associated with this fungus, although the organism is known to infect various organs of cattle.     

Macrohematuria and life-threatening anemia attributable to subepithelial vascular ectasia of the urinary bladder in a dog

Hematuria leading to life-threatening anemia was evaluated in a 9-year-old male dog. At surgery, an abnormal vessel resembling an ulcerated varicose vein was found on the surface of the bladder mucosa. After removal of the lesion, hematuria ceased and had not recurred 22 months later.     

Aphanomyces invadans and Ulcerative Mycosis in Estuarine and Freshwater Fish in Florida

Abstract

In the spring of 1998, the Florida Fish and Wildlife Research Institute received numerous reports of lesioned or ulcerated fish primarily from the St. Lucie Estuary on the southeast coast of Florida, an area known since the late 1970s for lesions of the ulcerative mycosis (UM) type. From these and archived reports, as well as others received from different areas of Florida, we documented that diseased specimens had randomly distributed skin ulcers (usually reddened or hemorrhagic) with raised irregular margins and, in some cases, deeply penetrating hyphae in the surrounding muscle tissue. Since 1998, 256 fish (comprising 18 species) with ulcerative lesions (from 15 different locations) were confirmed with hyphae in fresh squash preparation or by histological evaluation. Squash preparations revealed nonseptate, sparsely branching, thick-walled hyphae; histological sections revealed mycotic granulomas in the dermis that occasionally penetrated into the skeletal muscle. These pathological characteristics were consistent with UM caused by the oomycete Aphanomyces invadans in Southeast Asia, Japan, Australia, and the United States. For specific identification, six isolates from ulcerated fish were cultured and prepared for molecular characterization using established diagnostic methods. Ribosomal RNA gene sequence analysis identified three isolates as Aphanomyces invadans, one as the oomycete Achlya bisexualis, and two as the ascomycete Phialemonium dimorphosporum. A more extensive survey of 67 ulcerated skin samples from fish collected between 1998 and 2003 was performed using a polymerase chain reaction assay specific for Aphanomyces invadans. Of these, 26 (38.8%) samples from seven fish species and nine collection locations were positive. Confirmation of UM associated with Aphanomyces invadans represents new host records in Florida for the sheepshead Archosargus probatocephalus, striped mullet Mugil cephalus, white mullet Mugil curema, silver perch Bairdiella chrysoura, black drum Pogonias cromis, largemouth bass Micropterus salmoides, and American shad Alosa sapidissima.     

Results of adrenalectomy in 36 dogs with hyperadrenocorticism caused by adrenocortical tumour

Summary

A total of 38 adrenocortical tumours were removed from 36 dogs with hyperadrenocorticism. The surgical approach was by way of a unilateral flank laparotomy (32 dogs; 14 left and 18 right), a bilateral flank laparotomy (3 dogs) or a midline celiotomy (1 dog).

Two dogs were euthanized during surgery because their tumours could not be resected. Eight dogs died from post‐operative complications. Pancreatic necrosis with peritonitis was the most common cause of death. Eight of the 26 dogs that survived had signs of recurrence of hyperadrenocorticism. Unsuppressible hyperadrenocorticism was found in four dogs; one dog had probably pre‐existent pituitary‐dependent hyperadrenocorticism, and adrenocortical function could not be re‐examined in the remaining three dogs.

Among the 37 tumours examined microscopically expansion of neoplastic tissue into blood vessels was found in 22 of them. Four adrenal glands with adrenocortical tumours also contained phaeochromocytomas. Necropsy was performed in eight dogs. Metastases were found in the lungs of two dogs and in the lungs and liver in one dog.

In combination with the data of previous reports, it is suggested that histological findings in surgery specimens are not good predictors for the clinical outcome.     

CLINICAL SIGNIFICANCE AND PROGNOSIS OF DEEP DIGITAL FLEXOR TENDINOPATHY ASSESSED OVER TIME USING MRI

Deep digital flexor (DDF) tendinopathy is one of the most frequent causes of foot lameness and the prognosis is guarded. The progress of lesion healing may be followed by magnetic resonance (MR) imaging to formulate a prognosis and to adapt the rehabilitation program. We assessed the correlation of outcome with total tendon damage and temporal resolution of MR abnormalities. Images from 34 horses with DDF tendinopathy that had undergone at least two low‐field standing MR examinations of the foot (mean 2.5 ± 1.3 times) were reviewed. No horse having a T1‐GRE hyperintense lesion over 30 mm in length or over 10% tendon cross‐sectional area returned to its previous activity level. Horses with concomitant lesions had worse outcome than horses with DDF tendinopathy only (P = 0.005). In all horses including those with excellent outcome, the lesion persisted, even mildly, in T1‐GRE and PD images. Horses with tendon lesion resolution on STIR‐FSE and T2‐FSE images on recheck examination had a better outcome (P = 0.0004 and P = 0.002, respectively), and all horses that returned to their previous level of performance had complete resolution of signal hyperintensity on the STIR‐FSE sequence. Although rehabilitation remains multifactorial, characteristics of DDF tendinopathy and concomitant lesions on first and recheck MR examinations allow refining the prognosis.     

CT imaging features of fat stranding in cats and dogs with abdominal disorder

BackgroundFat stranding is a non-specific finding of an increased fat attenuation on computed tomography (CT) images. Fat stranding is used for detecting the underlying lesion in humans.ObjectivesTo assess the clinical significance of fat stranding on CT images for identifying the underlying cause in dogs and cats.MethodsIn this retrospective study, the incidence, location, extent, distribution, and pattern of fat stranding were assessed on CT studies obtained from 134 cases.ResultsFat stranding was found in 38% (51/134) of all cases and in 35% (37/107) of tumors, which was significantly higher in malignant tumors (44%) than benign tumors (12%). Moreover, fat stranding was found in more than two areas in malignant tumors (16/33) and in a single area in benign tumors (4/4). In inflammation, fat stranding was demonstrated in 54% (7/13) in a single area (7/7) as a focal distribution (6/7). In trauma, fat stranding was revealed in 50% (7/14) and most were in multiple areas (6/7). Regardless of the etiologies, fat stranding was always around the underlying lesion and a reticular pattern was the most common presentation. Logistic regression analysis revealed that multiple areas (p = 0.040) of fat stranding and a reticulonodular pattern (p = 0.022) are the significant predictors of malignant tumor.ConclusionsThese findings indicated that CT fat stranding can be used as a clue for identifying the underlying lesion and can be useful for narrowing the differential list based on the extent and pattern.     

P‐59 Three cases of opportunistic dermatoses associated with internal diseases in cats

Opportunistic dermatoses can occur in case of immunosuppressive diseases. The first case was a 12‐year‐old domestic short‐haired cat suffering from diabetes with a phaeohyphomycosis due to Scytalidium spp.associated with cutaneous hemangiosarcoma. A painless and ulcerated nodule was observed on a digit with fistulous tracts over the metatarsal joint. Histopathological examination of the nodule revealed a hemangiosarcoma in which brownish fungal colonies were found. Itraconazole (5 mg/kg twice daily), then amputation, allowed 12 months of survival (pulmonary metastases). The second case concerned a 13‐year‐old Siamese cat with cheyletiellosisassociated with spontaneous Cushing's disease and diabetes mellitus. This cat exhibited scales and miliary dermatitis on the trunk associated with polyuria, polydipsia and a pot‐belly. Acetate tape impression showed Cheyletiella blakei mites and eggs. Blood analysis revealed diabetes mellitus and spontaneous hyperadrenocorticism. The owner refused treatment. The third case was a 14‐year‐old domestic short‐haired cat with generalized demodicosis associated with iatrogenic Cushing's disease and diabetes mellitus. Long‐acting glucocorticoids had been used for treatment of plasma cell stomatitis for 5 years. This cat exhibited erythema, scales, self‐induced alopecia, thin skin and moderate pruritus associated with polyuria and polydipsia. Cutaneous lesions principally developed on the abdomen and flanks. Skin scrapings and trichogram showed numerous Demodex cati mites. Routine blood work demonstrated diabetes mellitus and iatrogenic Cushing's disease. Treatment was based on insulin therapy, milbemycin oxime (1 mg/kg once daily) and chlorambucil (0.2 mg/kg once daily). The demodicosis was cured after 4 months, but the cat died of cutaneous and ocular herpesvirus infection 10 months later. Funding: Self‐funded.     

RESEARCH PAPER: Incidence of elevation of cardiac troponin I prior to and following routine general anaesthesia in dogs

ObjectiveTo estimate the incidence of raised cTnI after general anaesthesia in dogs and to explore major risk factors influencing this.Study designProspective clinical study.AnimalsA total of 107 (ASA physical status 1?2) dogs, 63% male and 37% female, median age 5 years (range 0.3–13.4), median weight 24.4 kg (range 4.2–66.5 kg) undergoing anaesthesia for clinical purposes.MethodsVenous blood samples were taken within 24 hours prior to induction and 24 hours after the termination of anaesthesia. Serum concentrations of cardiac troponin I were measured using a chemiluminescent enzyme immunometric assay with a lower level of detection of 0.20 ng mL^?1 (below this level <0.20 ng mL^?1). Continuous data were assessed graphically for normality and paired and unpaired data compared with the Wilcoxon signed ranks and Mann–Whitney U‐tests respectively. Categorical data were compared with the Chi squared or Fisher’s exact test as appropriate (p < 0.05).ResultsOf the 107 dogs recruited, 100 had pre‐ and post‐anaesthetic cTnI measured. The median pre‐anaesthesia cTnI was ‘<0.20’ ng mL^?1 (range ‘<0.20’–0.43 ng mL^?1) and the median increase from pre‐anaesthesia level was 0.00 ng mL^?1 (range ?0.12 to 0.61 ng mL^?1). Fourteen dogs had increased cTnI after anaesthesia relative to pre‐anaesthesia (14%, 95% CI 7.2–20.8%, range of increase 0.03–0.61 ng mL^?1). Six animals had cTnI levels that decreased (range 0.02–0.12 ng mL^?1). Older dogs were more likely to have increased cTnI prior to anaesthesia (OR = 5.32, 95% CI 1.35–21.0, p = 0.007) and dogs 8 years and over were 3.6 times as likely to have an increased cTnI after anaesthesia (95% CI 1.1–12.4, p = 0.028).Conclusion and clinical relevanceIncreased cTnI after anaesthesia relative to pre‐anaesthesia levels was observed in a number of apparently healthy dogs undergoing routine anaesthesia.     

Actions of BW540C in an equine model of acute inflammation: A preliminary study

Summary

An equine model of acute non‐immune inflammation has been developed to facilitate studies of the inflammatory process and the actions of novel anti‐inflammatory drugs. Five polyester sponge strips soaked in sterile 2% carrageenin solution were placed in subcutaneous pouches prepared under local anaesthesia in the necks of conscious ponies. Serial removal of the strips and harvesting of the exudate enabled studies to be made of the cellular, biochemical and mediator aspects of the localised, acute inflammation, and the heat generated by the lesion was monitored by infra‐red thermometry. Maximal concentrations of the eicosanoids 6‐keto‐prostaglandin F_1α, thromboxane B₂ and leukotriene B, occurred at 9 h, whereas leukocyte numbers, lactate dehydrogenase (LDH) and total protein concentrations were greatest at 24 h. Lesional skin temperature was increased by approximately 4°C throughout the 24 h period. The novel anti‐inflammatory agent BW540C, administered orally at a dose‐rate of 20 mg/kg, did not affect leukocyte infiltration or the concentrations of protein, LDH and eicosanoids in exudate but serum thromboxane B₂ levels were reduced. Skin temperature rises were greater in drug‐treated animals.

It is concluded that higher doses of BW540C will be required for a clinically useful anti‐inflammatory action in horses.     

Effect of ephedrine and phenylephrine on cardiopulmonary parameters in horses undergoing elective surgery

ObjectiveTo assess the cardiopulmonary effects of ephedrine and phenylephrine for management of isoflurane‐induced hypotension in horses.Study designProspective randomized clinical study.AnimalsFourteen isoflurane‐anesthetized horses undergoing digital palmar neurectomy.MethodsEphedrine (EPH group; 0.02 mg kg^?1 minute^?1; n = 7) or phenylephrine (PHE group; 0.002 mg kg^?1 minute^?1; n = 7) was administered to all horses when mean arterial pressure (MAP) was <60 mmHg. The infusions were ended when the target MAP was achieved, corresponding to a 50% increase over the pre‐infusion MAP (baseline). The horses were instrumented with an arterial catheter to measure blood pressure and allow the collection of blood for pH and blood‐gas analysis and a Swan‐Ganz catheter for measurement of cardiac output using thermodilution. Cardiopulmonary parameters were recorded at baseline and at 5, 30, 60 and 90 minutes after achieving the target MAP.ResultsIn both groups, the MAP and systemic vascular resistance (SVR) increased significantly at 5, 30, 60 and 90 minutes post infusion compared to baseline (p < 0.05). The EPH group had a significant increase in cardiac index (CI) and systemic oxygen delivery index at 5, 30, 60 and 90 minutes post infusion compared to baseline (p < 0.05) and compared to the PHE group (p < 0.05). The PHE group had significantly higher SVR and no decrease in oxygen extraction compared with the EPH group at 30, 60 and 90 minutes post infusion (p < 0.05). No significant differences in ventilatory parameters were observed between groups after the infusion.ConclusionsEphedrine increased the MAP by increasing CI and SVR. Phenylephrine increased MAP by increasing SVR but cardiac index decreased. Ephedrine resulted in better tissue oxygenation than phenylephrine.Clinical relevanceEphedrine would be preferable to phenylephrine to treat isoflurane‐induced hypotension in horses since it increases blood flow and pressure.     

Detection of two different papillomaviruses within a feline cutaneous squamous cell carcinoma: Case report and review of the literature

CASE HISTORY A 15-year-old, brown-and-white cat was presented to a veterinary clinic with an ulcerated, reddened 1-cm diameter lesion on the nasal planum.

CLINICAL FINDINGS AND DIAGNOSIS: Histology of a biopsy sample confirmed the lesion was a squamous cell carcinoma (SCC). PCR amplified DNA sequences from two different papillomaviruses. One sequence was from FdPV 2, which has previously been amplified from feline cutaneous SCC. However, the other sequence has not previously been reported, suggesting a novel feline papillomavirus.

CLINICAL RELEVANCE: There is evidence that papillomaviruses promote the development of SCC on sun-exposed skin in humans. This is the first report in a cat of a papillomavirus other than FdPV2 and the first time that multiple papillomaviruses have been detected within a single neoplasm in this species. Whether the papillomaviruses influenced the development and behaviour of this SCC is currently uncertain, but this case provides additional evidence of the association between papillomaviruses and feline cutaneous SCC. If papillomaviruses are found to influence the development of SCC this may allow novel strategies to prevent these common neoplasms in cats.     

Short-term temporal alterations in magnetic resonance signal occur in primary lesions identified in the deep digital flexor tendon of the equine digit

Reasons for performing study: Primary lesions of the deep digital flexor tendon (DDFT) within the digit are an important cause of lameness diagnosed using magnetic resonance imaging (MRI) but appearance of these lesions over time has not been documented. Objectives: To determine whether the magnetic resonance (MR) appearance of different primary DDFT lesions alter over a 6 month period and whether lesion type is a determinant of these changes. Methods: Cases included had lameness attributable to a primary lesion involving the DDFT in the digit diagnosed on MRI. Lesions were typed into parasagittal, dorsal border and core lesions. Approximate volumes and intensities were quantified for each lesion type using T2* scan sequences. Follow‐up examinations and measurements were repeated at 3 and 6 month periods following conservative management. Results: Twenty‐three horses fitted the inclusion criteria. Lesion distribution included: parasagittal (n = 7), dorsal border (n = 11) and core lesions (n = 5). No association was found between age of horse, degree of lameness and lesion type. Only dorsal border lesions showed statistically significant reduction both in volume (initial scan: 0.18 ± 0.14 cm³) at 3 months (0.11 ± 0.10 cm³, P<0.05) and 6 months (0.05 ± 0.05 cm³, P<0.01) and ratiometric intensity (initial scan: 4.06 ± 1.54) at 6 months (2.00 ± 0.43; P<0.01). Parasagittal and core lesions showed no difference in lesion volume or ratiometric intensity. Lameness improved in all lesion types following conservative management. Conclusions: Dorsal border lesions of the DDFT show reduction in both volume and intensity whereas parasagittal and core lesions do not. Potential relevance: Lesion typing may be important in predicting lesion behaviour and short‐term outcome using MR imaging.     

Susceptibility of Selected Inland Salmonids to Experimentally Induced Infections with Myxobolus cerebralis,the Causative Agent of Whirling Disease

Abstract

Laboratory exposures to the infectious stages (triactinomyxons) of Myxobolus cerebralis demonstrated a range of susceptibility to whirling disease among four species of inland salmonids. Replicate groups of each species were exposed to two concentrations of triactinomyxons, a low dose (100–200 per fish) and a high dose (1,000–2,000 per fish). Exposed fish were evaluated for clinical signs, for severity of microscopic lesions at 35 d, 2 and 5 months, and for spore concentrations in the head cartilage at 5 months. A standard strain of rainbow trout Oncorhynchus mykiss matched for age served as a susceptible species control. Rainbow trout, westslope cutthroat trout O. clarki lewisi, Yellowstone cutthroat trout O. clarki bouvieri, and bull trout Salvelinus confluentus were susceptible to M. cerebralis infections. Clinical signs, including radical swimming (“whirling”) and black tails, were observed at 7 weeks postexposure among rainbow and cutthroat trout challenged at 3 weeks of age. Clinical signs were rare among bull trout exposed at an age of 4 weeks and absent among rainbow and cutthroat trout exposed at 3 months posthatch. Most rainbow, cutthroat, and bull trout were found to be infected when examined at 5 months postexposure. The most severe microscopic lesions among infected fish at 5 months postexposure were found among rainbow trout. Cutthroat trout had less severe lesions, bull trout had mild infections, and no evidence of infection was found among Arctic grayling Thymallus arcticus. Mean spore concentrations among infected fish correlated with the severity of microscopic lesion scores. Rainbow trout had mean concentrations of spores in head cartilage reaching 10⁶, whereas more resistant species such as bull trout had 10⁴ spores; no spores were found among Arctic grayling at 5 months postexposure.     

Response of feline eosinophilic plaques and lip ulcers to amoxicillin trihydrate-clavulanate potassium therapy: a randomized, double-blind placebo-controlled prospective study

In this study, we evaluated the treatment of feline eosinophilic plaques and lip ulcers with amoxicillin trihydrate–potassium clavulanate (Clavamox^®; Pfizer Animal Health). Nineteen cats with clinical and cytological findings consistent with eosinophilic plaques and/or lip ulcers were enrolled. Lesions were photographed and their areas measured in square centimetres before and after 21 days of therapy with either flavoured amoxicillin‐clavulanate suspension or flavoured placebo suspension. Sixteen cats completed the study, with nine plaque lesions (four treatment and five placebo) and eight lip ulcer lesions (four treatment and four placebo) included in the analysis. All lesions were shown to have infection, with bacterial phagocytosis present on cytological examination. Coagulase‐positive staphylococci were the most commonly isolated bacteria. The amoxicillin‐clavulanate‐treated eosinophilic plaque group had a statistically significant 96.2% reduction in mean lesion size (?7.60 cm², P = 0.0078) and an 80% reduction in mean percentage of microscopic fields demonstrating evidence of bacterial infection (P < 0.0001), whereas the placebo group did not. The amoxicillin‐clavulanate‐treated lip ulcer group had a 42.6% decrease in mean lesion size (?0.25 cm², P = 0.4125) and the placebo group a 36.6% increase (+0.49 cm², P = 0.1575), although neither change was statistically significant. The amoxicillin‐clavulanate‐treated lip ulcer group had a statistically significant 65.0% reduction in mean percentage of microscopic fields demonstrating evidence of bacterial infection (P < 0.0001), while no significant reduction was observed in the placebo group. A suspension of amoxicillin trihydrate–potassium clavulanate is an effective monotherapy for the treatment of feline eosinophilic plaques.     

Grass defoliation affecting survival and growth of seedlings of Acacia karroo,an encroaching species in southwestern Zimbabwe

Abstract

Two experiments were conducted, one in the field and the other in the greenhouse, to investigate the effects of the intensity and frequency of grass defoliation on the survival and growth of Acacia karroo seedlings. In the greenhouse, seedlings growing with heavily clipped grasses had higher biomass production than those competing with moderately clipped grasses. Root/shoot ratios were higher in treatments with undipped grasses. There was a negative relationship between grass root production and A. karroo biomass production. The field experiment was carried out in two paddocks, one previously heavily‐grazed and the other lightly‐grazed. Grazing in both paddocks was simulated by artificial defoliation. Generally more A. karroo seedlings emerged under lightly defoliated treatments. Clipping frequency had a strong effect (P=0.066) on the survival of emerged seedlings during the wet season. There were no differences in survival rate at the end of the dry season. Though grass defoliation was shown to enhance seedling growth under controlled conditions, no evidence was found to suggest that seedling establishment during the first year is influenced by the intensity of grass defoliation.