P506 First case of cutaneous mycosis caused by Nannizziopsis sp. in Chelonia

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

The present report characterized a case of severe superficial and deep mycoses in a yellow-bellied slider (Trachemys scripta scripta) caused by Nannizziopsis sp. detected by histopathology and fungal culture.

 

A female, 4-year-old, yellow-bellied slider (Trachemys scripta scripta) was presented for ulcerative and proliferative, chronic, skin lesions. White to pink, slightly round, with fuzzy borders, 0.5-2.5 cm in diameter, multifocal, proliferative, and ulcerative lesions were evident mainly on the left forelimb, right forelimb, pericloacal, chin, and oral cavity. The left forelimb was severely affected by a nodular subcutaneous mass.

Several courses of disinfectant therapy, antibiotic, and antifungal treatments were given with no clinical improvements.

Cytological smears of the ulcerative skin lesion revealed macrophages, heterophils, and fragments of septate hyphae.

 

To investigate the cause of the lesions, the left forelimb was excised, fixed in 10% neutral buffered formalin, and submitted for histopathological examination. Biopsies and swabs from left forelimb, right forelimb, chin, and oral lesions were submitted for microbiological analysis.

Samples were cultured on Sabouraud Dextrose Agar (SDA) and incubated at 30°C for 10 days.

 

Histopathological examination showed severe pyogranulomatous dermatitis and myositis. Numerous septate, irregularly branched hyphae were evident within the pyogranulomas. Grocott methenamine silver stain (GMS) and Periodic acid-Schiff (PAS) confirmed the presence of filamentous fungi in the examined sections.

Pure cultures of the same fungal strain were obtained from all the samples.

 

Mature colonies on SDA showed a powdery aspect and a white felted surface. Microscopically, the hyphae were straight and branched, and conidia were clavate, sessile, or on short stalks.

Based on both macroscopic and microscopic features the fungal strain was identified as Nannizziopsis sp.

Susceptibility profile of the fungal isolate was tested for griseofulvin, miconazole, fluconazole, voriconazole, itraconazole, clotrimazole, and ketoconazole.

 

Amplification and sequencing of ITS, 18S, and SSU gene regions have been performed to identify the fungal isolate. The sequences were aligned with the most similar sequences of established species deposited in GenBank in order to define levels of relatedness. Sequences showed that the isolate clustered with Nannizziopsiaceae.

 

The sequence similarities of the isolate were 99% to N. arthrosporioides in ITS (535/543 bps), 99% to N. vriesii in 18S, and SSU (1648/1649 and 970/973 bps, respectively).

Based on the histopathological, microbiological, and molecular analysis, Nannizziopsis sp. was the primary cause of severe deep mycoses in the present turtle.

 

Mycoses caused by Chrysosporium-related fungi are an emerging infectious disease affecting reptiles. The fungi of this group were collectively identified as Chrysosporium anamorph of Nannizziopsis vriesii (CAVN) complex by their morphological characteristics. Recent molecular taxonomy studies have now re-classified Chrysosporium-related fungi into three genera: Nannizziopsis, Paranannizziopsis, and Ophidiomyces.

Until now, nine species have been isolated and identified from reptiles.

 

Dermatomycosis associated with Nannizziopsis spp. is frequently reported in lizards, terrestrial, and aquatic snakes, and crocodiles, with classical cutaneous ulcerative lesions. Cutaneous mycosis is common in turtles, however, to our knowledge this is the first case of Nannizziopsis cutaneous mycosis in Chelonia.

P477 In vitro synergy of combination therapy against antifungal-resistant Candida spp. isolated from captive bottlenose dolphins (Tursiops truncatus)

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM

The study aimed to evaluate antifungal resistance in Candida spp. isolated from captive bottlenose dolphins (Tursiops truncatus). Due to the need to find a therapy for symptomatic animals and to the presence of azole-resistant isolates, in vitro synergy of 3 antifungal combinations has been assayed.

 

A total of seven captive bottlenose dolphins were examined. Two dolphins showed mild aspecific symptoms, one was receiving nystatin due to gastric candidiasis, and the other four animals were asymptomatic. The presence of Candida spp. was investigated in fecal, gastric fluid, and blow samples from each dolphin twice.

 

Samples were cultured on Sabouraud Dextrose Agar and ChromAgar Candida at 30°C for 5 days. CHROMagar colonies consistent with Candida spp. were identified.

 

Susceptibility tests were performed according to CLSI standard with amphotericin B (AB), 5-flucytosine (FC), itraconazole (IZ), fluconazole (FZ), miconazole (MCZ), posaconazole (PZ), voriconazole (VOR), caspofungin (CAS), anidulafungin (AND), and micafungin (MF). In addition, minimum inhibitory concentration (MIC) for nystatin (NYS) and terbinafine (TER) was determined.

 

Based on the most common therapies in dolphins, assessment of the interaction between FZ and TER, VOR and TER, and VOR and NYS was carried out determining the fractional inhibitory concentration (FIC) index by checkerboard assay.

 

Out of 42 samples analyzed, 30 were positive for Candida spp. identified as C. albicans (n=21), C. tropicalis (n=6), and C. glabrata (n=3).

 

All the isolates showed resistance to azoles. A total of 50% of the isolates showed resistance to FC and 23.3% to AMB. No isolate showed resistance to echinocandins.

 

MIC values ranged from 16 to 128 µg/ml for TER (arithmetic mean 107.8 µg/ml) and from 8 to 128 µg/ml (arithmetic mean 51.8 µg/ml) for NYS.

 

The FIC index value for FLU and TER showed a synergistic effect on 71.4% and an additive effect on 28.6% of the tested isolates.

 

For VOR and TER an additive effect on 71.4% and a synergistic effect on 28.6% of the isolates were detected.

 

For VOR and NYS an antagonistic effect on 71.4% and an additive effect on 28.6% of the isolates were detected.

 

According to the results, combination therapy with FLU and TER was started. Symptoms resolved completely.

 

Candida spp. has been isolated from mucous membranes of free-living asymptomatic dolphins. However, a high load of Candida spp. may cause clinical signs.

 

As azoles are the most used antifungals in dolphins, azole-resistance is increasing. Since the tested dolphins had no recent history of azole treatment, it could be speculated that resistance might come from the environment. Thus, further studies and screening of multidrug-resistant Candida spp. in animals and their environment are needed to better understand resistance transmission in a One Health approach.

 

Moreover, susceptibility testing is important to select the appropriate therapy. In case of azole-resistant Candida spp., antifungals other than azoles alone or in combination should be considered.

 

Our study demonstrates that fluconazole exhibits in vitro synergistic antifungal activity with terbinafine against azole-resistant strains of C. albicans, C. tropicalis and C. glabrata isolated from captive bottlenose dolphins.

Clinical, surgical, and pathological findings in client-owned rabbits with histologically confirmed appendicitis: 19 cases (2015-2019)

OBJECTIVE

To report clinical, surgical, and pathological findings in client-owned rabbits with histologically confirmed appendicitis.

ANIMALS

19 rabbits.

PROCEDURES

Medical records for client-owned rabbits that had a histologic diagnosis of appendicitis were reviewed.

RESULTS

Median age of the rabbits at presentation was 24.0 months (range, 4 to 84 months). Seventeen cases occurred during the summer and fall seasons. Decreased appetite (17/19 rabbits), abnormal rectal temperature (hyperthermia, 9/16 rabbits; hypothermia, 4/16 rabbits), hypocalcemia (8/11 rabbits), and hypoglycemia (7/15 rabbits) were common signs. Abdominal ultrasonography and CT findings were suggestive of appendicitis in 6 of 8 rabbits and in 1 of 2 rabbits, respectively. Of the 6 rabbits that received medical treatment, 3 died at 48 hours, 1 died at 24 hours after hospitalization, and 1 died at 10 days after presentation; 1 rabbit was alive at 1,030 days after presentation. Of the 8 rabbits that underwent appendectomy, 3 died before discharge from the hospital and 1 died 113 days after surgery; 4 rabbits were alive at 315, 334, 1,433, and 1,473 days after presentation. The remaining 5 rabbits either died or were euthanized before treatment could be instituted. In each of the 19 rabbits, the appendix had evidence of severe inflammation with mucosal ulceration, heterophilic inflammation, and necrotic debris.

CLINICAL RELEVANCE

For rabbits with decreased appetite and an apparently painful abdomen, hyperthermia, hypocalcemia, or hypoglycemia, appendicitis should be considered as a differential diagnosis. Further comparisons of medical and surgical treatments are required to establish treatment recommendations for rabbits with appendicitis.

Molecular characterization of Prototheca in 11 symptomatic dogs

Protothecosis is an uncommon disease caused by algae of the genus Prototheca. In dogs, the infection is usually first localized to the colon but has the propensity to later disseminate hematogenously to many other organs, with marked tropism for the eyes and central nervous system. Diagnosis is established by culture and/or evidence of Prototheca organisms in cytologic or histologic preparations. Species characterization, however, requires molecular investigations. Our laboratory set up a real-time PCR targeting portion D1/D2 of the 28S rRNA for identification of Prototheca species from both positive cultures (of rectal swabs and urine) and formalin-fixed, paraffin-embedded tissue. Prototheca bovis, P. ciferrii, and P. wickerhamii were characterized in 11 dogs with systemic or cutaneous protothecosis. Prototheca identifications were phylogenetically consistent with the new taxonomy proposed for this genus based on the mitochondrial cytochrome b gene. As a pilot study, we screened feces and rectal scrapes from 200 asymptomatic dogs, using 2 cohorts of stray and owned animals, to determine the prevalence of intestinal carriage of Prototheca spp. The Prototheca-negative results from both cohorts of healthy dogs suggest that predisposing factors related to the host probably contribute more to the acquisition of clinical disease than exposure to contaminated environments.

Epidemiology of Breed-Related Mast Cell Tumour Occurrence and Prognostic Significance of Clinical Features in a Defined Population of Dogs in West-Central Italy

Canine mast cell tumours (MCTs) present a wide variety of challenging clinical behaviours in terms of predicting the prognosis and choosing appropriate treatment. This study investigated the frequency, risk, and prognostic factors of MCTs in dogs admitted to a single veterinary teaching hospital (VTH). Breed, age, sex, and sexual status in ninety-eight dogs with MCTs (MCT-group) were compared with a control group of 13,077 dogs (VTH-group) obtained from the VTH clinical database from January 2010 to January 2016. Within the MCT-group, signalment, location, size, mass number, ulceration, histopathological grading, presence of lymph node, or distant metastases were compared with each other and with the outcome. Boxers (OR 7.2), American Pit Bull Terriers (OR 5.4), French Bulldogs (OR 4.4) and Labrador Retrievers (OR 2.6) were overrepresented. The MCT-group was significantly older than the VTH-group (p < 0.0001). In comparison with the VTH group, in the MCT-group neutered dogs (OR 2.1) and spayed females (OR 2.3) were predominant compared to intact dogs and intact females, respectively. Ulceration (OR 5.2) and lymph node metastasis (OR 7.1) occurred more frequently in larger MCTs. Both ulceration and MCTs > 3 cm were highly associated with lymph node metastasis (OR 24.8). Recurrence was associated with MCT-related death (OR 10.50, p = 0.0040), and the latter was associated with shorter survival times (p = 0.0115). Dogs with MCTs > 3 cm (p = 0.0040), lymph node metastasis (p = 0.0234), or elevated WHO stage (p = 0.0158) had shorter survival times. A significantly higher frequency of MCTs was found in specific breeds, and in older and neutered dogs. MCTs > 3 cm and lymph node or distant metastases were associated with shorter survival times.

Sertoli cell tumour in a pet rabbit (Oryctolagus cuniculus): histological and immunohistochemical characterization

The present study describes a case of a spontaneous, unilateral Sertoli cell tumour (SCT) in a 6-year-old pet rabbit. The rabbit was presented with a palpable, unilateral, subcutaneous left inguinal mass, consistent with the suspected clinical diagnosis of neoplasia developing within the retained testis in the inguinal canal. The intrascrotal contralateral testis was palpable, but reduced in volume. The rabbit underwent orchiectomy and both the testes were collected, formalin-fixed, and submitted for histopathological examination. Microscopically, the enlarged testis was effaced by an intratubular SCT in which numerous intratubular microliths were evident. The contralateral testis was severely atrophied. Immunohistochemical stains showed neoplastic Sertoli cells that were diffusely positive for vimentin and anti-Müllerian-Hormone and multifocally positive for cytokeratins and desmin. Eighteen months after the surgery, the rabbit showed no clinical signs of disease. This is the first report of a spontaneously occurring rabbit SCT histologically described and immunohistochemically investigated.

Canine Clitoral Carcinoma: A Clinical, Cytologic, Histopathologic, Immunohistochemical, and Ultrastructural Study

Vaginal and vulvar tumors are uncommon in dogs. Knowledge of canine primary clitoral neoplasia is restricted to a few case reports, and only carcinomas have been reported. Cytologic and histologic features reported in the literature seem to overlap with those of canine apocrine gland anal sac adenocarcinoma (AGASA). Clinical features also recall those of canine AGASA, such as locoregional metastases and hypercalcemia of malignancy (HM). In this study, 6 cases of primary canine clitoral carcinomas (CCCs), with and without HM, were investigated by means of cytology, histopathology, electron microscopy, and immunohistochemistry for neuroendocrine markers including chromogranin A (CGA), synaptophysin (SYN), neuron-specific enolase (NSE), and S-100. In all 6 tumors, cytologic findings were consistent with malignant epithelial neoplasia of apocrine gland origin. The tumors examined were classified into 3 different histological patterns representing different degrees of differentiation: tubular, solid, and rosette type. Both CGA and SYN were mildly expressed in 2 of 6 tumors, while NSE was consistently expressed in all 6 cases. None of the tumors were S-100 positive. Transmission electron microscopy revealed electron-dense cytoplasmic granules compatible with neuroendocrine granules in all 6 cases. CCCs presented clinicopathologic features resembling AGASAs with neuroendocrine characteristics, and 2 of 6 neoplasms were considered as carcinomas with neuroendocrine differentiation and were positive for 3 neuroendocrine markers. CCCs can often present with HM, and long-term outcome is likely poor. Our study concludes that CCC seems to be a rare tumor, but it might be underestimated because of the overlapping features with AGASA. Further studies should aim to define the true incidence of this disease.

A study of multiple Felis catus papillomavirus types (1, 2, 3, 4) in cat skin lesions in Italy by quantitative PCR

Objectives The aim of the study was to investigate, by quantitative PCR (qPCR), the presence of papillomavirus in feline viral plaques (VPs), Bowenoid in situ carcinoma (BISC), squamous cell carcinoma (SCC) and actinic keratosis (AK). Methods Twenty-nine cases with previously established diagnoses of feline VPs, BISC, invasive SCC and AK were selected from a dermatopathological database. A critical re-evaluation of diagnosis was performed by defining clear criteria toward carcinomatous vs non-carcinomatous, in situ vs invasive (if carcinomatous) and viral vs actinic. Cases were evaluated for p16 immunolocalisation. The presence of the target viral genes for Felis catus papillomavirus (FcaPV)-1, FcaPV-2, FcaPV-3 and FcaPV-4 was determined by qPCR. The data generated ΔΔCq values, which represent a normalised measure of DNA viral quantity. Samples with a positive ΔΔCq value were submitted to sequence analysis. Results Four VPs, 19 BISCs, four SCCs and one case of AK were included. By ΔΔCq analysis we found that all VPs were positive for FcaPV-1 or FcaPV-2; eight BISCs were positive for FcaPV-1, FcaPV-2 and FcaPV-4. FcaPV-2 was the most prevalent among the group of VPs and BISCs. Conclusions and relevance Using the ΔΔCq method we report the first evidence of FcaPV-1, FcaPV-2 and FcaPV-4 in Italy. FcaPV-2 was the most frequently detected; to a lesser extent, FcaPV-1 and FcaPV-4 were detected in the examined samples. FcaPV-3 was never associated with viral-induced lesions by ΔΔCq investigation. Compared with conventional PCR the ΔΔCq method has the advantage of establishing a possible role of the virus in the outcome of infection.

Laryngeal paralysis associated with a muscle pseudotumour in a young dog

An 18-month-old male entire Bloodhound dog was presented with a six-week history of progressive inspiratory dyspnoea, stridor, dysphonia and exercise intolerance. CT scan performed elsewhere had revealed the presence of an unencapsulated nodular mass (3x1x5 cm) dorsal to the larynx and first tracheal rings. Laryngoscopy demonstrated the presence of bilateral laryngeal paralysis and distorted laryngeal architecture suggestive of extraluminal compression. Histopathology results of incisional biopsies from the mass were suggestive of a benign non-neoplastic muscular lesion. Surgery was performed to manage laryngeal paralysis and attempt mass excision. A second histopathology examination confirmed an inflammatory and dysplastic lesion suggestive of a pseudotumour. All clinical signs resolved after surgery and at the 13 months follow-up the dog remains asymptomatic. To the authors’ knowledge, this is the first report of a case of laryngeal paralysis caused by a muscle pseudotumour in a young dog.

Primary leiomyosarcoma of the jugular vein in a dog

A four-year-old, male, Labrador retriever was referred for removal of a spindle cell sarcoma involving the right jugular vein. A post-contrast CT scan showed a seven-centimeter subcutaneous mass originated from the right external jugular vein, which was partially obstructed and showing contrast stasis, suggested a primary intravascular tumor of the jugular vein. The mass was resected, and histological evaluation was consistent with grade II intravenous spindle cell sarcoma of the jugular vein. Immunohistochemical positivity for vimentin, desmin, and αSMA antibody and negativity for S-100 protein confirmed venous leiomyosarcoma. The dog received five doses of intravenous doxorubicin, and there was no recurrence of the tumor 30 months post treatment. In dogs, primary intravascular sarcomas are rare and primary venous leiomyosarcoma has not been described. A venous tumor may be considered as a differential diagnosis in dogs with ventral neck swelling.

A rare case of pituitary chromophobe carcinoma in a dog: clinical, tomographic and histopathological findings

A 9 year old male mixed-breed dog was presented for progressive aggressiveness towards the owner. The neurological evaluation was consistent with a forebrain syndrome. Magnetic Resonance Imaging (MRI) of the brain revealed enlargement of the third ventricle and presence of a large spheroidal neoplasm in the sellar/parasellar region suggestive of a pituitary macroadenoma. On the owner request, the dog was euthanized. Histopathological examination revealed the presence of a pituitary chromophobe carcinoma. To the author’s knowledge, pituitary carcinomas have been rarely described in dogs, especially the chromophobe subtype.

Calvaria and orbital metastases of pulmonary adenosquamous carcinoma in a cat: a diagnostic challenge

An 11-year-old cat with a 4-month history of lethargy, inappetence, dysphagia, partial mandibular paralysis and weight loss, was euthanized due to the rapid deterioration of his condition. Post-mortem radiographic examination revealed severe bone lysis of the left zygomatic arch, temporal and parietal bones. Magnetic resonance imaging of the head showed a large isointense mass of the left side of the skull associated with extensive lysis of the parietal and temporal bones and destruction of the adjacent tympanic bulla. Gross and histological examinations revealed a pulmonary adenosquamous carcinoma of the left lung, with metastases to the spleen, liver, mesenteric lymph nodes, mesentery, diaphragm, abdominal aorta, left orbit and calvaria. No limb or digit metastases were detected.

Detection of Pneumocystis infections by in situ hybridization in lung samples of Austrian pigs with interstitial pneumonia

Pneumocystis carinii f. sp. suis is a fungus multiplying in the respiratory tract of pigs which occasionally is associated with interstitial pneumonia. Identification of Pneumocystis in tissue samples is considered difficult and there are only scarce data on its occurrence in European pigs. This investigation presents an in situ hybridization (ISH) procedure for identification of Pneumocystis spp. in paraffin wax embedded tissue samples and its application for labeling the agent in lung samples of pigs with interstitial pneumonia. Thirty-two out of 100 lung samples from pigs on Austrian farms were identified as positive, five of them with multiple, 12 with moderate and 15 with few organisms but Grocott’s methenamine silver staining demonstrated that only 20 cases were unequivocally positive for Pneumocystis carinii. In addition to interstitial pneumonia Pneumocystis-positive pigs were more frequently affected with granulomatous pneumonia than Pneumocystis-negative pigs. Frequently concurrent infections with different viral or bacterial lung pathogens were noted but there was no positive correlation between Pneumocystis- and PCV-2-infections. With other infections, no clear-cut differences between Pneumocystis-positive and Pneumocystis-negative animals were found. This study shows that Pneumocystis infections occur frequently in Austrian pigs with interstitial pneumonia. It remains to be shown which are the factors triggering severe multiplication and whether infection with Pneumocystis alone is able to induce lung disease in pigs.

Severe thymic hyperplasia in a newborn calf associated with impaired T-cell differentiation

A 1-day-old female Holstein–Friesian calf was presented for severe dyspnea. Physical examination revealed respiratory distress, moderate edema of the ventral neck, and swollen jugular veins. The calf died and was submitted for necropsy. A severely enlarged thymus (40 cm × 20 cm × 10 cm) weighing 1.37 kg was detected on gross examination. Histomorphology was normal but no tingible body macrophages were observed in the medullary areas. Immunohistochemistry was characterized by the lack of thymic cluster of differentiation 3 and major histocompatibility complex class II expression compared to age-matched controls. The findings were consistent with severe thymic hyperplasia, a rare congenital condition that is also described in children. Immunohistochemical findings were suggestive of impaired T-cell development and selection associated with lack of apoptosis of thymic cells (lack of tingible body macrophages). Thymic hyperplasia in juvenile animals should be considered among the differential diagnoses of mediastinal masses as a rare cause of respiratory distress in newborn calves.

A case of umbilical cord teratoma in an aborted foal

A 16-year-old primiparous mare aborted an apparently normal fetus at 240 days of gestation. A large, oval mass, measuring approximately 20 cm × 30 cm × 20 cm, was detected attached to the umbilical cord of the fetus. On the cut surface, the mass showed multifocal cystic structures, foci of mineralization, and diffuse hemorrhages. Histological examination of the mass revealed haphazardly arranged cartilage, bone, mesenchymal stroma, adipose tissue, vascular structures, smooth muscle, ciliated epithelium, squamous cornifying epithelium, and undifferentiated germ cells with areas of necrosis and mineralization. The mass was diagnosed as an umbilical cord teratoma, which is an extremely rare tumor in human beings and, to the authors’ knowledge, has only described in the veterinary literature on one occasion.

Segmental spinal cord hypoplasia in a Holstein Friesian calf

An 8-day-old female Holstein Friesian calf was examined because of congenital spastic paresis of the hind limbs. Myelography revealed deviation and thinning of subarachnoid contrast medium columns in the lumbar segment. Upon magnetic resonance imaging, the 'hour-glass' subdural compression appeared as a T1-hypointense, T2-hyperintense ovoidal area suggestive of cerebral spinal fluid collection, compatible with hydrosyringomyelia. The calf was euthanized and the necropsy confirmed the diagnosis of segmental spinal cord hypoplasia of the lumbar tract associated to hydromyelic and syringomyelic cavities.

Perineal Choristoma and Atresia Ani in 2 Female Holstein Friesian Calves

Atresia ani, a congenital anomaly of the anus, can be associated with other types of malformation. Two female Holstein Friesian calves had imperforate anus, rectovaginal fistula, and perineal choristomas. In one case, the choristoma was composed of mature adipose and fibrous tissue with nephrogenic rests. In the other calf, the choristoma consisted of fragments of trabecular bone coated by cartilage and containing marrow, mixed with mature adipose and fibrous tissue, striated muscle fibers, nerves, and vessels. This combination of malformations resembles the association of anorectal malformations and perineal masses in children.

Thoraco-omphalopagus conjoined twins in Chamois-coloured domestic goat kids

Conjoined twins have been observed in a wide range of mammalian and non-mammalian species; they are considered to be more common in bovine, less frequent in sheep and pig and extremely rare in horse and goat. A pair of female conjoined twins was delivered from a 2-year-old Chamois-coloured domestic goat. Post-mortem examination revealed two identical and symmetrical twins, fused from the manubrium sterni to the region just caudal to the umbilicus. The rib cages were conjoined in the ventral plane with a single set of pericardial, pleural and peritoneal cavities. Internal examination revealed the presence of a common diaphragm and a single enlarged liver. Within a single central pericardium, two malformed hearts were present. Reports on this type of congenital duplication in goats have not been found in the literature. Thoracopagus and thoraco-omphalopagus are the most common types of conjoined twins in human beings and are associated with the highest mortality because of the frequent incidence of complex cardiac anatomy.