Cryptococcosis in cats: ABCD guidelines on prevention and management

Itraconazole in human medicine and veterinary practice

Diagnosis and management of fungal infections are challenging in both animals and humans, especially in immunologically weakened hosts. Due to its broad spectrum and safety profile when compared to other antifungals, itraconazole (ITZ) has been widely used in the treatment and prophylaxis of fungal infections, both in human and veterinary medicine. The dose and duration of management depend on factors such as the type of fungal pathogen, the site of infection, sensitivity to ITZ, chronic stages of the disease, the health status of the hosts, pharmacological interactions with other medications and the therapeutic protocol used. In veterinary practice, ITZ doses generally vary between 3 mg/kg and 50 mg/kg, once or twice a day. In humans, doses usually vary between 100 and 400 mg/day. As human and veterinary fungal infections are increasingly associated, and ITZ is one of the main medications used, this review addresses relevant aspects related to the use of this drug in both clinics, including case reports and different clinical aspects available in the literature.

Diagnosis and management of Cryptococcus neoformans var. grubii detected in an oral mass in a pink-tongued skink (Cyclodomorphus gerarrdii)

Cryptococcus is an encapsulated yeast that is found in both yeast and hyphal forms. Cryptococcus neoformans and C. gattii are the most medically important species, causing disease in both immunocompromised and immunocompetent individuals. A large, friable, sublingual mass was surgically resected from the oral cavity of a pink-tongued skink (Cyclodomorphus gerarrdii). Histopathology, fungal culture and PCR testing with Sanger sequencing confirmed granulomatous inflammation containing large numbers of yeasts identified as Cryptococcus neoformans var. grubii. Surgical excision and treatment with oral amphotericin B and terbinafine was unsuccessful in managing the infection. On Day 67 after surgery, Cryptococcus DNA was detected by PCR in the blood but not oral, cloacal or skin swabs. The skink was euthanised 72 days after surgery due to anorexia, weight loss and progressive neurological signs of disease. Necropsy results showed disseminated cryptococcosis, including meningoencephalitis and ventriculitis. Two in-contact pink-tongued skinks remained asymptomatic and PCR-negative during 198 days of observation. This case suggests Cryptococcus infections should be considered for oral masses presenting with or without neurological signs in skinks. Further investigation is required to determine the best treatment options for disseminated cryptococcosis in reptiles. This report describes the third reported case of Cryptococcus in a reptile and the first case of cryptococcosis in a pink-tongued skink. It is also the first report of Cryptococcus in a reptile identified to the variety level using PCR, including in whole blood samples.

A case of disseminated cryptococcosis with abdominal involvement due to Cryptococcus neoformans species complex in a Ragdoll cat and false-negative cryptococcal antigen lateral flow tests due to the postzone phenomenon

Although cryptococcosis is the most common systemic fungal disease of cats, abdominal involvement is rarely reported. The pathogenesis of cryptococcosis usually involves sinonasal colonisation, followed by tissue invasion and sinonasal infection, with possible subsequent spread to the lungs and/or direct extension into the central nervous system (CNS), for example, via the cribriform plate. Further haematogenous spread can occur to any tissue, including skin and the CNS. This report describes a case of disseminated cryptococcosis due to Cryptococcus neoformans species complex in a 13-year-old cat, the fourth documented Australian feline case with abdominal involvement. The cat presented with a chronic history of upper respiratory disease that progressed to severe lethargy and anorexia. An autopsy revealed striking peritonitis with multifocal abdominal involvement affecting the liver, spleen, adrenal glands, kidneys, pancreas and mesentery. Cryptococcal organisms were also observed in organs within the thoracic cavity, sinonasal tissues and the CNS. Testing of abdominal fluid and serum for cryptococcal antigen using a commercially available lateral flow assay using neat fluid specimen initially tested false-negative. However, after dilution of the sample to 1:64, a positive result was obtained, confirming a postzone phenomenon. Taken together, the collective findings were indicative of widely disseminated cryptococcosis due to Cryptococcus neoformans with atypical involvement of the abdominal cavity.

Fungal diversity and drug susceptibility of the oral mycobiome of domestic dogs

The purpose of this study was to characterize the variety and diversity of the oral mycobiome of domestic dogs and to identify the commensal and potentially pathogenic fungi present. Two hundred fifty-one buccal swabs from domestic dogs were obtained and struck onto a chromogenic fungal growth medium that distinguishes between fungal species based on colony color and morphology. After isolating and harvesting single colonies, genomic DNA was extracted from pure cultures. PCR was used to amplify a fungal-specific variable rDNA region of the genome, which was then sent for sequencing. Sequencing results were input into the NCBI BLAST database to identify individual components of the oral mycobiome of tested dogs. Of the 251 dogs swabbed, 73 had cultivable fungi present and 10 dogs had multiple fungal species isolated. Although the dogs did not show signs of oral infections at the time, we did find fungal species that cause pathogenicity in animals and humans. Among fungal isolates, Malassezia pachydermatis and species from the genus Candida were predominant. Following fungal isolate identification, antifungal drug susceptibility tests were performed on each isolate toward the medically important antifungal drugs including fluconazole, ketoconazole, and terbinafine. Drug susceptibility test results indicated that a large number of isolates had high MIC values for all three drugs. Exploring the oral mycobiome of dogs, as well as the corresponding drug susceptibility profiles, can have important implications for canine dental hygiene, health, and medical treatment. Identifying the microorganisms within the canine mouth can illustrate a common pathway for fungal pathogens of One Health concern to spread from our canine companions to humans.

First report of oral cryptococcal osteomyelitis in a cat

Cryptococcosis is a worldwide-distributed fungal disease affecting humans and animals and is considered the most common systemic mycosis in cats. Classically, the clinical presentation of cryptococcal infection in cats consists of solitary or multiple nodules located on the planum nasale or the bridge of the nose. Bone involvement as cryptococcal osteomyelitis is a rare clinical entity of cryptococcosis. Herein, this case report describes a domestic shorthair cat with osteomyelitis of the mandibular bone resulting from Cryptococcus spp. infection. During the physical examination, a subcutaneous mass measuring approximately 6 cm in diameter was identified at the mandibular region. Cytological evaluation revealed numerous encapsulated yeasts resembling Cryptococcus spp. Histopathological examination revealed multifocal to coalescent subcutaneous granulomatous inflammation with a large number of spherical yeasts surrounded by a clear capsule. These yeasts were positive for periodic acid-Schiff (PAS) staining. The cat was successfully treated with a combination of itraconazole therapy and surgical management. To the author's knowledge, this is the first clinical report of oral cryptococcal osteomyelitis in a cat.

Discovery of a Novel Antimicrobial Peptide, Temporin-PKE, from the Skin Secretion of Pelophylax kl. esculentus, and Evaluation of Its Structure-Activity Relationships

Bacterial resistance against antibiotics has led to increasing numbers of treatment failures, and AMPs are widely accepted as becoming potential alternatives due to their advantages. Temporin-PKE is a novel peptide extracted from the skin secretion of Pelophylax kl. esculentus and it displays a strong activity against Gram-positive bacteria, with an extreme cytotoxicity. Incorporating positively charged residues and introducing D-amino acids were the two main strategies adopted for the modifications. The transformation of the chirality of Ile could reduce haemolytic activity, and an analogue with appropriate D-isoforms could maintain antimicrobial activity and stability. The substitution of hydrophobic residues could bring about more potent and broad-spectrum antimicrobial activities. The analogues with Lys were less harmful to the normal cells and their stabilities remained at similarly high levels compared to temporin-PKE. The optimal number of charges was three, and the replacement on the polar face was a better choice. Temporin-PKE-3K exerted dually efficient functions includingstrong antimicrobial and anticancer activity. This analogue showed a reduced possibility for inducing resistance in MRSA and Klebsiella pneumoniae, a rather strong antimicrobial activity in vivo, and it exhibited the highest therapeutic index such that temporin-PKE-3K has the potential to be developed as a clinical drug.

Insight into the Role of Psychological Factors in Oral Mucosa Diseases

With the development of psychology and medicine, more and more diseases have found their psychological origins and associations, especially ulceration and other mucosal injuries, within the digestive system. However, the association of psychological factors with lesions of the oral mucosa, including oral squamous cell carcinoma (OSCC), burning mouth syndrome (BMS), and recurrent aphthous stomatitis (RAS), have not been fully characterized. In this review, after introducing the association between psychological and nervous factors and diseases, we provide detailed descriptions of the psychology and nerve fibers involved in the pathology of OSCC, BMS, and RAS, pointing out the underlying mechanisms and suggesting the clinical indications.

Nasopharyngeal cryptococcosis in a cat: interlaboratory variation in cryptococcal antigen assay test results

Case summary

An indoor-only 6-year-old spayed female domestic cat was evaluated for a history of stertorous respiration. Skull radiographs revealed increased soft tissue density within the caudal aspect of the left nasal cavity. CT and rhinoscopy revealed a mass lesion in the choana, plus a smaller lesion, nearly completely occluding flow through the nasal passages. Rhinoscopy was used to collect a biopsy specimen from a fleshy, tan–yellow mass visualized in the caudal nasopharynx. Histopathology was diagnostic for Cryptococcus species infection and systemic antifungal therapy with fluconazole was initiated. Following a series of discordant results, serum samples were submitted to a veterinary diagnostic laboratory that utilized a cryptococcal antigen latex agglutination system with pretreatment of serum with pronase. Twenty-three months after the initial diagnosis, the cat’s serum cryptococcal antigen titer declined to 1:5 and the cat has responded well to continuing treatment.

Relevance and novel information

This case illustrates challenges associated with discordant test results for cryptococcal antigen among laboratories. Discordancies may be due to differences in assay design, or the underlying disease state itself, or whether serum is pre-treated with pronase; with some tests relying on the training and experience of the operator if the cryptococcal antigen detection test requires a subjective interpretation. It also resolves some confusion in the literature related to the assay types available and terminology used to describe them, and emphasizes the importance of considering cryptococcosis as an important differential for cats with upper respiratory signs, without nasal discharge, even if the cat is kept exclusively indoors.

Causes and Lesions of Fatal Pneumonia in Domestic Cats

Pneumonia in cats may cause severe lung injury and consequent death. We describe the post-mortem findings and aetiologies of naturally fatal pneumonia in 78 domestic cats, using gross and histopathological examinations, immunohistochemistry and microbiological techniques. Morphological patterns found were bronchopneumonia (27/78), interstitial (15/78), bronchointerstitial (13/78), granulomatous (8/78), aspiration (8/78) and pyogranulomatous (5/78) pneumonia, and pleuropneumonia (2/78). Bacterial pneumonia was identified as the most common cause (32/78), followed by viral (15/28 feline calicivirus, 10/28 felid alphaherpesvirus 1 and 3/28 both viruses), aspiration (8/78), fungal (5/78) and parasitic pneumonia (5/78). Co-infection with feline immunodeficiency virus and feline leukaemia virus was found in 54 cats. Viral infections involved cats of all ages, indicating the importance of investigating viral causes in cats with respiratory diseases, including in adult and ageing cats.

Anthraquinones from Aloe spp. inhibit Cryptococcus neoformans sensu stricto: effects against growing and mature biofilms

This study aimed to evaluate the in vitro effect of aloe emodin, barbaloin and chrysophanol on growing and mature biofilms of Cryptococcus neoformans sensu stricto. The compounds were added at the moment of inducing biofilm growth or after growth for 72 h to evaluate their effects on growing and mature biofilms, respectively. Then, biofilm biomass was evaluated by crystal violet staining and metabolic activity by the XTT reduction assay. Morphological alterations were also evaluated by laser scanning confocal microscopy. Aloe emodin and barbaloin affected growing biofilms and disrupted mature biofilms, reducing metabolic activity by > 60% and biomass by > 70%. Chrysophanol only inhibited mature biofilms, but to a lesser extent. In conclusion, anthraquinones, especially aloe emodin and barbaloin, show a relevant effect against growing and mature biofilms of C. neoformans sensu stricto.

First report of a subcutaneous infection by Cryptococcus neoformans (former Cryptococcus neoformans var. grubii) in a cat in Costa Rica

This is a case report of a feline animal that presented with a skin infection on the neck from which Cryptococcus neoformans (former C. neoformans var. grubii) was isolated and identified. The cat presented two nodular tumors, approximately 2 cm in diameter, raised, solid, with a slightly irregular surface and a reddish color with white areas. Histologically, these tumors corresponded to granulomatous dermatitis and panniculitis with the presence of a large number of intralesional yeasts. From identification with biochemical and spectroscopic techniques of these lesion samples, it was determined that the etiological agent was C. neoformans. There is little information on this variety of Cryptococcus causing subcutaneous infection without involvement of other organs, and the presence of this pathogen in the few reports available has not been reliably determined. This is the first report of a cat affected by C. neoformans in Costa Rica.

Diagnostic and therapeutic management of Cryptococcosis in a kitten with practical considerations to veterinary pediatric therapeutic approach

A 3-months-old male domestic kitten was referred for repeated seizures. Analysis revealed Cryptococcus neoformans. Levetiracetam and fluconazole were administered without significant clinical improvements and without negativization. Hypothesizing resistance, therapy was switched to amphotericin B. Seizure disappeared. Haematological controls highlighted transitory increasing of CK, BUN, ALP and cholesterol. PCR repeated two weeks after the treatment was negative for Cryptococcus neoformans. Nowadays the cat is 5 years old, and no seizures occurred since the age of 5 months.

Abdominal cryptococcosis in dogs and cats: 38 cases (2000-2018)

INTRODUCTION

To report the clinical presentation, laboratory and imaging findings, treatment and outcome of abdominal cryptococcosis in dogs and cats in Australia.

MATERIALS AND METHODS

Canine and feline cases from Australia were retrospectively identified (2000 to 2018) via laboratory and referral centre searches for abdominal cryptococcosis diagnosed by cytology (needle aspirates) or histopathology (biopsy or necropsy) of abdominal organs/tissues. Signalment, presenting complaints, clinical signs, laboratory findings, medical imaging, latex cryptococcal antigen agglutination test (LCAT) titres, treatment and outcome data was collected.

RESULTS

Thirty-eight cases were included (35 dogs, three cats) in the study. Median age of presentation was 2 years for dogs and 6 years for cats. Common presenting complaints included vomiting (23/38), lethargy (19/38) and inappetence/anorexia (15/38). Abdominal ultrasound (25/38 cases) revealed mesenteric and intestinal lesions in most of the cases. On surgical exploration, seven cases had an intestinal lesion associated with an intussusception. Nineteen cases had a pre-treatment LCAT performed, with a median initial titre of 1:2048 (range 1:2 to 65,536). Twenty-four cases (23 dogs, one cat) received treatment, either medical, surgical or both. Median survival time for cases with combined medical and surgical treatment, surgical treatment alone or medical treatment alone was 730, 140 and 561 days, respectively. Eleven remain alive at the time of follow up.

CLINICAL SIGNIFICANCE

Abdominal cryptococcosis although rare should be a considered as a diagnostic possibility in an especially young dog presenting with gastro-intestinal signs. Older dogs can also present with this condition and should not be euthanised based on imaging alone due to the likenesses with neoplasia. With appropriate treatment and monitoring many dogs may have a prolonged survival period and some may be cured.

Facial distortion due to chronic inflammation of unknown cause in a cat

Case summary

An 8-year-old neutered male indoor cat was presented for evaluation of a year-long history of swelling over the bridge of the nose that extended from the subcutaneous tissue of the right upper eyelid to the dorsum of the skull. Intermittent regression of the mass lesion was reported with antibiotic or corticosteroid therapy; however, progressive swelling, malaise and hiding behavior persisted. CT revealed an aggressive osteolytic mass lesion in the right and left nasal cavities and extending into the frontal sinuses. Rhinoscopy using a 2.8 mm rigid telescope revealed somewhat normal-appearing turbinates rostrally and ventrally on the left side, with turbinate destruction on the right. After obtaining a biopsy from the right side of the nasal cavity, thick material filling the entire nasal cavity was visible caudally and was extracted endoscopically from a rostral approach. Surgical biopsy of the dorsal nasal bridge resulted in protrusion of inspissated material from the incision site. Rhinoscopic exploration revealed that the material extended into both frontal sinuses. Following extensive debridement and medical therapy, marked resolution of facial asymmetry was achieved.

Relevance and novel information

Facial distortion is often considered suggestive of a neoplastic process; however, it can also be seen with fungal and mycobacterial infections, and, in this case, an inflammatory condition of unknown etiology. In this cat, aggressive intervention and debridement of necrotic debris resulted in substantial bony remodeling of the skull and return to normal activity levels.

Antifungal effect of anthraquinones against Cryptococcus neoformans: detection of synergism with amphotericin B

The emergence of tolerant Cryptococcus neoformans strains to antifungals has been described. It has directed researchers to screen for new antimicrobial compounds. In this context, several plant-derived compounds, such as anthraquinones (aloe emodin, barbaloin, and chrysophanol), have been investigated for their antimicrobial properties. This study aimed to evaluate the in vitro effect of aloe emodin, barbaloin and chrysophanol on C. neoformans in vitro growth. In addition, the interaction between these anthraquinones and amphotericin B and itraconazole was evaluated. Initially, the minimum inhibitory concentrations (MIC) of these compounds were determined against 17 strains of C. neoformans by the broth microdilution method and then pharmacological interaction assays were performed with 15 strains by the checkerboard method. Aloe emodin, barbaloin, and chrysophanol showed minimum inhibitory concentrations of 236.82-473.65 μM (64-128 μg/mL), 153-306 μM (64-128 μg/ml) and ≥1007 μM (≥256 μg/ml), respectively. Furthermore, aloe emodin (11/15), barbaloin (13/15), and chrysophanol (12/15) showed pharmacological synergism (FICI < 0.5) with amphotericin B at subinhibitory concentrations (MIC/4). The itraconazole-aloe emodin interaction was additive (1/15) (0.5 < FICI < 1.0). The itraconazole-barbaloin interaction were synergistic (2/15) and additive (5/15); whereas itraconazole-chrysophanol interactions were additive (2/15). Anthraquinones, especially aloe emodin and barbaloin, present in vitro antifungal activity against C. neoformans and potentiate the antifungal activity of amphotericin B.

Distinguishing Between Dermatologic Disorders of the Face, Nasal Planum, and Ears: Great Lookalikes in Feline Dermatology

Facial dermatitis in cats can be caused by a broad range of infectious, allergic, immune-mediated and neoplastic disorders with very different treatments and prognoses. Baseline dermatologic diagnostics (skin scrapings for mites, cytology for infection and to characterize inflammatory infiltrate, and dermatophyte culture) are required, as well as possible further diagnostics, including therapeutic trials for parasites and feeding a hypoallergenic diet, bacterial culture, and skin biopsies for histopathology in order to achieve a diagnosis. Clinical presentations of diseases affecting different parts of the feline face are presented and discussed.

Feline cutaneous nodular and ocular Cryptococcus neoformans in Belgium

Case summary

An 11-year-old spayed female cat presented with a 6-month history of a progressive nodular skin disease with concurrent, ocular lesions, intermittent vomiting, halitosis and weight loss. The cat had received different topical treatments without success prior to referral to the Dermatology Department of Faculty of Veterinary Medicine, Ghent University. Several fine-needle aspirations of the lesions showed a vast number of macrophages with intra-cytoplasmic inclusions compatible with Cryptococcus species. Histopathological examination revealed pyogranulomatous inflammation with capsulated yeast. Periodic acid–Schiff stain was positive. Latex cryptococcal antigen agglutination test on serum was positive with a titre of >1/524,288. PCR and fungal culture identified Cryptococcus neoformans. The cat was treated with itraconazole 10 mg/kg PO q24h. After 10 months of therapy, there was a complete resolution of the lesions except for a small nodule on the ventral aspect of the tongue.

Relevance and novel information

As far as we are aware, this is the first feline case reported of cutaneous nodular cryptococcosis without nasal involvement in Belgium. Oral itraconazole therapy was well tolerated and appeared to give a good result and prognosis.

First case of a dog infected with Aspergillus (Phialosimplex) caninus in Australasia

Case history: A 2-year-old Rottweiler dog from Perth (WA, Australia) was referred for assessment of a chronic productive cough and weight loss.Clinical findings: Severely enlarged bilateral superficial cervical lymph nodes and severely enlarged abdominal organs were present. The body condition score was poor and there was moderate muscle wasting. Thoracic and abdominal computed tomography images revealed severe diffuse enlargement of thoracic and abdominal lymph nodes, hepatomegaly and diffuse splenomegaly. A diffuse bronchial pattern with severe multifocal saccular bronchiectasis was identified in the lungs.Diagnostic findings: Fungal organisms were seen within macrophages on cytological preparations and on histopathological sections of biopsies of the superficial cervical lymph node. Macrophages contained intracytoplasmic, non-filamentous round-to-ovoid organisms, which varied in size from 5-30 µm in diameter with variable morphology. Budding was not observed, and no hyphae were present. Fungal culture of lymph node tissue resulted in growth of Aspergillus (Phialosimplex) caninus which was confirmed by amplification and sequencing of a segment of the 16S-23S rRNA internal transcribed spacer. Concurrent bacterial bronchitis was diagnosed on culture of broncho-alveolar fluid.Diagnosis: Disseminated aspergillosis caused by Aspergillus caninus.Clinical relevance: This is believed to be the first report of infection caused by A. caninus in a dog in Australasia. The dog was treated with itraconazole for 7 months and was still alive 7 months after the start of treatment.

CT identifies pulmonary cryptococcosis in a domestic feline

A domestic cat was presented for lethargy and coughing. Thoracic radiographs identified a mass within the right cranial lung lobe and a nodule in the left cranial lung lobe. Cryptococcus spp. was diagnosed via ultrasound-guided fine needle aspirate cytology. Despite fluconazole and prednisolone treatment, clinical signs progressed and suggested airway obstruction. Computed tomography revealed mass invasion into the trachea and other areas of the lower airway resulting in obstruction. Bronchoscopy was performed to debulk the tracheal mass and obtain biopsies. Histopathology confirmed Cryptococcus spp. At the time of this report, the patient remained clinically stable with daily itraconazole (5 mg/kg) treatment.

Intranasal Inoculation of Cryptococcus neoformans in Mice Produces Nasal Infection with Rapid Brain Dissemination

Cryptococcus neoformans is an important fungal pathogen, causing life-threatening pneumonia and meningoencephalitis. Brain dissemination of C. neoformans is thought to be a consequence of an active infection in the lung which then extravasates to other sites. Brain invasion results from dissemination via either transport by free yeast cells in the bloodstream or Trojan horse transport within mononuclear phagocytes. We assessed brain dissemination in three mouse models of infection: intravenous, intratracheal, and intranasal models. All three modes of infection resulted in dissemination of C. neoformans to the brain in less than 3 h. Further, C. neoformans was detected in the entirety of the upper respiratory tract and the ear canals of mice. In recent years, intranasal infection has become a popular mechanism to induce pulmonary infection because it avoids surgery, but our findings show that instillation of C. neoformans produces cryptococcal nasal infection. These findings imply that immunological studies using intranasal infection should assume that the initial sites of infection of infection are brain, lung, and upper respiratory tract, including the nasal airways.IMPORTANCECryptococcus neoformans causes an estimated 181, 000 deaths each year, mostly associated with untreated HIV/AIDS. C. neoformans has a ubiquitous worldwide distribution. Humans become infected from exposure to environmental sources, after which the fungus lays dormant within the human body. Upon AIDS-induced immunosuppression or therapy-induced immunosuppression (required for organ transplant recipients or those suffering from autoimmune disorders), cryptococcal disease reactivates and causes life-threatening meningitis and pneumonia. This study showed that upon contact with the host, C. neoformans can quickly (a few hours) reach the host brain and also colonizes the nose of infected animals. Therefore, this work paves the way to better knowledge of how C. neoformans travels through the host body. Understanding how C. neoformans infects, disseminates, and survives within the host is critically required so that we can prevent infections and the disease caused by this deadly fungus.

Isolation of Cryptococcus gattii from feline chronic stage lipoid pneumonia

We hereby report a unique manifestation of feline cryptococcosis in the form of extensively consolidated lipoid pneumonia resulting in an isolated space-occupying lung lobe mass. Lung lobectomy was performed and a diagnosis of severe lipoid pneumonia with intra-lesional Cryptococcus gattii was made. The patient was asymptomatic for respiratory disease and no abnormalities of the upper respiratory tract were identified. Anti-fungal therapy was initiated following the diagnosis and the patient recovered without complication.

Cryptococcal pathogenic mechanisms: a dangerous trip from the environment to the brain

Cryptococcus neoformans is an opportunistic pathogenic yeast that causes serious infections, most commonly of the central nervous system (CNS). C. neoformans is mainly found in the environment and acquired by inhalation. It could be metaphorically imagined that cryptococcal disease is a "journey" for the microorganism that starts in the environment, where this yeast loads its suitcase with virulence traits. C. neoformans first encounters the infected mammalian host in the lungs, a site in which it must choose the right elements from its "virulence suitcase" to survive the pulmonary immune response. However, the lung is often only the first stop in this journey, and in some individuals the fungal trip continues to the brain. To enter the brain, C. neoformans must "open" the main barrier that protects this organ, the blood brain barrier (BBB). Once in the brain, C. neoformans expresses a distinct set of protective attributes that confers a strong neurotropism and the ability to cause brain colonisation. In summary, C. neoformans is a unique fungal pathogen as shown in its ability to survive in the face of multiple stress factors and to express virulence factors that contribute to the development of disease.

Skin as a marker of general feline health: Cutaneous manifestations of infectious disease

Practical relevance: Infectious disease in feline patients often presents a diagnostic challenge. This article reviews the most relevant viral, bacterial and protozoal diseases and their cutaneous manifestations. Many of the diseases discussed have overlapping presentations or may mimic more common noninfectious disease processes. The purpose of the article is to reinforce knowledge of common and uncommon infectious diseases, help practitioners identify possible infectious dermatoses, create a comprehensive and prioritized differential list, and provide guidance for the diagnosis of these diseases. A working knowledge of these clinical syndromes is important if what is thought to be a case of a common disease does not respond to conventional management.

AUDIENCE

This review is aimed at veterinarians who treat cats and especially those with an interest in feline dermatology. Tables are included to allow the reader to formulate a concise list of differential diagnoses for clinically similar presentations. The diagnostic approach to a case of ulcerative facial dermatitis is reviewed in a Case Notes quiz. Evidence base: This article includes up-to-date information regarding dermatologic manifestations of less commonly encountered feline cutaneous infectious diseases. Information has been drawn from the published, peer-reviewed literature and the most recent textbook chapters with a particular aim of describing and differentiating clinical lesions and the diagnostic approach to cutaneous disease, especially in unusual cases.

Doenças micóticas em gatos no Rio Grande do Sul

RESUMO: As enfermidades fúngicas são diagnósticos diferenciais de diversas morbidades de caráter infeccioso, degenerativo ou proliferativo neoplásico, principalmente em gatos, que é a espécie mais suscetível a estas. Este trabalho descreve os achados anatomopatológicos de doenças fúngicas em gatos no período de janeiro de 2005 a dezembro de 2015 pelo SPV-UFRGS. Foram revisados 1.274 protocolos de necropsia e encontrou-se 17 casos de micoses, correspondendo a 1,33% dos diagnósticos. Quanto às amostras provenientes de biopsias, foram verificados 2.615 protocolos e detectou-se 59 casos de doenças fúngicas, totalizando 2,25% dos diagnósticos, sendo revisados seus achados macroscópicos, microscópicos, colorações especiais e cultivo micológico. O principal diagnóstico encontrado foi esporotricose com 34 casos de biópsia e cinco de necropsia. Criptococose obteve seis diagnósticos na necropsia e 13 na biópsia. O pseudomicetoma dermatofítico possui cinco casos de biópsia e dois de necropsia. Histoplasmose obteve um diagnóstico na necropsia e dois na biópsia. Aspergilose teve dois casos diagnosticados na necropsia. Candidíase e feo-hifomicose obtiveram um caso cada. Em quatro ocasiões, não se pode identificar o agente envolvido na lesão e foram classificados conforme a alteração morfológica em: dermatite fúngica, enterite fúngica, rinite micótica e dermatite e osteomielite fúngica. Através deste trabalho, pode-se identificar que a esporotricose foi o diagnóstico de doença fúngica mais frequente em felinos, seguido da criptococose e pseudomicetoma dermatofítico.

Skin as a marker of general feline health: Cutaneous manifestations of systemic disease

Practical relevance: Although most skin lesions occur due to diseases primarily affecting the skin, some reflect important systemic diseases. Such lesions may relate directly to the systemic disease, or may occur due to secondary skin diseases that develop because of immunosuppression. Early recognition of skin changes as a marker of systemic disease will maximise patient outcomes. Clinical challenges: In older or clearly debilitated cats presenting with skin disease, the potential for underlying systemic disease is often readily apparent. Similarly, cats presenting with severe ulcerative or multifocal nodular skin lesions, or with concurrent signs of systemic illness, will more instinctively prompt systemic evaluation. More challenging is the cat presenting with alopecic, scaling, erythemic and/or mildly crusted skin disease, with or without pruritus; hypersensitivities and infectious dermatoses are the most common considerations, but occasionally systemic disease underlies the skin changes. Knowing when screening laboratory testing, body imaging or other systemic diagnostics are indicated is not always straightforward. Evidence base: This article reviews cutaneous presentations of systemic diseases reported in the veterinary literature, and discusses important differential diagnoses. The author draws on clinical experience, published data on disease prevalence and case evaluations, and expert opinions on approach to common systemic problems to provide guidance on when investigation for underlying systemic disease is most appropriate.

Atypical Morphology and Disparate Speciation in a Case of Feline Cryptococcosis

A 6-year-old, spayed female cat was presented with acute respiratory signs and pleural effusion. Computed tomography scan revealed a large, lobulated mass effect in the ventral right hemithorax with concurrent sternal lymphadenopathy. A cytologic sample of the mass contained pyogranulomatous inflammation, necrotic material, and abundant yeast structures that lacked a distinct capsule and demonstrated rare pseudohyphal forms. Fungal culture and biochemical testing identified the yeast as Cryptococcus albidus, with susceptibility to all antifungal agents tested. However, subsequent 18S PCR identified 99% homology with a strain of Cryptococcus neoformans and only 92% homology with C. albidus. The patient responded well to fluconazole therapy unlike the only known previous report of C. albidus in a cat. The unusual cytologic morphology in this case underscores the need for ancillary testing apart from microscopy for fungal identification. Though C. albidus should be considered as a potential feline pathogen, confirmation with PCR is recommended when such rare non-neoformans species are encountered.

Equine Pulmonary Cryptococcosis: A Comparative Literature Review and Evaluation of Fluconazole Monotherapy

Cryptococcus is the most common fungal respiratory pathogen in Australian horses, manifesting primarily as pulmonary granulomas. Disease severity at presentation is dependent on the athletic use of the horse. The diagnosis and estimation of disease severity are centred around clinical findings, cytological evaluation of respiratory tract secretions, diagnostic imaging, and antigen titre testing. Both the lateral flow assay and the latex cryptococcal antigen titre are used, and important similarities and differences between species are discussed. Cryptococcus gattii occurs with greater frequency than Cryptococcus neoformans in equine pulmonic cryptococcosis and can be successfully treated with enteral fluconazole monotherapy, with disease severity determining treatment length.

Cryptococcus gattii Type VGIIa Infection in Harbor Seals ( Phoca vitulina ) in British Columbia, Canada

Cryptococcosis has been reported in marine mammals in the northeastern Pacific with increasing frequency in the last 15 yr. Although a variety of cetaceans have been diagnosed with cryptococcosis, Cryptococcus gattii has not been reported in pinnipeds. We document C. gattii VGIIa in a harbor seal ( Phoca vitulina ) pup and in an unrelated adult. Both animals were presented to Vancouver Aquarium's Marine Mammal Rescue Centre (VAMMRC) with generalized weakness, dehydration, respiratory compromise, minimally responsive mentation, and suboptimal body condition. Necropsy and histopathology findings were consistent in both animals and featured generalized lymphadenopathy, bronchopneumonia, and meningoencephalitis with intralesional yeast and fungemia. Cryptococcal serum antigen titers were ≥1,024 in both animals. Fungal culture of lung and lymph nodes confirmed C. gattii . Exposure was likely via inhalation prior to presentation to VAMMRC, and C. gattii infection was the proximate cause of death. This report expands the range of susceptible host species as C. gattii continues to emerge as a pathogen of concern in marine mammals in the northeastern Pacific.

Something old, something new: Update of the 2009 and 2013 ABCD guidelines on prevention and management of feline infectious diseases

OVERVIEW

The ABCD has published 34 guidelines in two Special Issues of the Journal of Feline Medicine and Surgery (JFMS): the first in July 2009 (Volume 11, Issue 7, pages 527-620) and the second in July 2013 (Volume 15, Issue 7, pages 528-652). The present article contains updates and new information on 18 of these (17 disease guidelines and one special article 'Prevention of infectious diseases in cat shelters'). For detailed information, readers are referred to the guidelines published in the above-mentioned JFMS Special Issues.

Cryptococcal nasopharyngeal polypoid mass in a cat

Case summary

An indoor 9-year-old castrated male domestic cat was referred with a 4 month history of increased upper airway noise. Computed tomography revealed a nasopharyngeal polypoid mass, which was removed endoscopically with basket forceps. Histopathology was compatible with a polypoid granulomatous pharyngitis with Cryptococcus-like organisms. This was supported by a positive serum latex cryptococcal antigen agglutination test (LCAT). Minimal inflammation of the nasal tissue was noted on histopathology, with no evidence of fungus. Following endoscopic removal of the mass, the patient was treated with systemic antifungal medication (itraconazole). One year after diagnosis, the LCAT titer was negative and the cat remained free of clinical signs.

Relevance and novel information

This case report emphasizes the importance of considering Cryptococcus species as a potential etiology in cats presented with signs of nasopharyngeal obstruction with an isolated nasopharyngeal polypoid mass, even if kept indoors.

Blepharitis due to Cryptococcus neoformans in a cat from northern Portugal

Case summary We report a clinical case of blepharitis due to Cryptococcus neoformans yeasts in a 2-year-old stray cat from northern Portugal (Vila Real) without concurrent naso-ocular signs. Ophthalmological examination revealed mucopurulent discharge from an open wound in the right upper and lower lids. Slit-lamp biomicroscopy showed a normal anterior segment, and intraocular pressure was within the normal reference interval. No fundoscopic alterations were detected in either eye by direct and indirect ophthalmoscopic examination. Cytological examination of an appositional smear showed numerous polymorphic neutrophils and macrophages, together with spherical yeast cells compatible with Cryptococcus species. Molecular analysis by means of PCR and restriction fragment length polymorphism identified C neoformans genotype VNI. The cat was treated with itraconazole, and amoxicillin and clavulanic acid, combined with a commercial ear ointment and an imidacloprid/moxidectin spot-on application for bilateral parasitic otitis caused by Otodectes cynotis. One month after treatment, the clinical signs were completely resolved. Localised cutaneous lesions, as in the present case, probably result from contamination of cat-scratch injuries with viable encapsulated yeasts.

Relevance and novel information This is, to the best of our knowledge, the first clinical report of feline blepharitis due to C neoformans without concurrent naso-ocular signs. The current findings, together with those from recent reports of the infection in domestic animals, should alert the veterinary community both in Portugal and in Europe to this underdiagnosed disease.