Potential role of Alternaria and Cladosporium species in canine lymphoplasmacytic rhinitis

Diversity and functional prediction of fungal communities in different segments of mongolian horse gastrointestinal tracts

BACKGROUND

Anaerobic fungi are effective fibre-degrading microorganisms in the digestive tract of horses. However, our understanding of their diversity and community structure is limited, especially in different parts of the gastrointestinal tract.

RESULTS

For the first time, high-throughput sequencing technology was used to analyse and predict fungal microbial diversity in different parts of the gastrointestinal tract of Mongolian horses. The results revealed that the richness and diversity of fungi in the hindgut of Mongolian horses were much higher than those in the foregut. The foregut was dominated by Basidiomycota and Ascomycota, whereas the hindgut was dominated by Neocallimastigomycota and Basidiomycota. At the genus level, the relative abundance of many pathogenic fungi (Cryptococcus, Cladosporium, Alternaria, and Sarocladium) in the foregut was significantly higher than that in the posterior gut, indicating that Mongolian horses have strong disease resistance. The prediction of fungal function also showed significant differences in the fungal flora between the foregut and the hindgut. The fungi in Mongolian horses' foreguts were mainly pathologically nutritive and contained many animal and plant pathogens, particularly in the small intestine (jejunum and ileum). This indicates that the foregut may be the most important immune site in the digestive system of Mongolian horses, which explains the high disease resistance of Mongolian horses. The number of unassigned functional groups in the posterior gut was significantly higher than that in the anterior gut, indicating that the functions of fungal groups in the posterior gut have not been fully explored, and further studies are required in the future.

CONCLUSIONS

Analysis of high-throughput sequencing results revealed that the fungal composition varied greatly among different gastrointestinal tract segments in Mongolian horses, whose hindgut contains many anaerobic fungi involved in plant cellulose degradation. This provides important basic data for studying fungal diversity in the digestive system of healthy horses, which can be used for the health assessment of horses and provides clues for further research on the disease resistance and digestive capacity of horses, as well as a reference for the early diagnosis of intestinal diseases and innovative treatment methods.

Seasonal variation of airborne fungal diversity and community structure in urban outdoor environments in Tianjin, China

Airborne fungi are ubiquitous in human living environments and may be a source of respiratory problems, allergies, and other health issues. A 12 months study was performed to investigate the diversity, concentration and community structure of culturable airborne fungi in different outdoor environments of Tianjin City, using an HAS-100B air sampler. A total of 1,015 fungal strains belonging to 175 species and 82 genera of Ascomycota 92.5%, Basidiomycota 7%, and Mucoromycota 0.3% were isolated and identified using morphological and molecular analysis. The most abundant fungal genera were Alternaria 35%, Cladosporium 18%, Penicillium 5.6%, Talaromyces 3.9%, Didymella 3%, and Aspergillus 2.8%, while the most frequently occurring species were A. alternata (24.7%), C. cladosporioides (11%), A. tenuissima (5.3%), P. oxalicum (4.53%), and T. funiculosus (2.66%). The fungal concentration ranged from 0 to 340 CFU/m³ during the whole study. Environmental factors, including temperature, relative humidity, wind speed, and air pressure exerted a varying effect on the presence and concentration of different fungal taxa. The four analyzed seasons showed significantly different airborne fungal communities, which were more strongly influenced by air temperature and relative humidity in spring and summer, whereas wind speed and air pressure had a stronger effect in autumn and winter. Fungal communities from green and busy sites did not show significant differences over the four analyzed seasons, which may be due to the effect of the surrounding environments characterized by high human activities on the air of the relatively small parks present in Tianjin. The present study provided valuable information on the seasonal dynamics and the environmental factors shaping the diversity and concentration of the analyzed outdoor airborne fungal communities, which can be of help for air quality monitoring, microbial contamination control, and health risk assessment in urban environments.

Utility of fungal polymerase chain reaction on nasal swab samples in the diagnosis and monitoring of sinonasal aspergillosis in dogs

Background

In dogs with sinonasal aspergillosis (SNA) the utility of PCR in the diagnosis and monitoring of the disease after treatment has not been assessed.

Objectives

To evaluate the presence of fungal DNA using quantitative PCR targeting Aspergillus fumigatus (Aspfum) and Aspergillus spp. (PanAsp), and PCR targeting multiple fungal species (PanFun), in samples obtained from nasal cavities of dogs with SNA, other nasal diseases and healthy dogs.

Animals

Sixty‐two dogs including 20 with SNA, 12 with cured SNA (of which 10 are from the SNA group), 20 dogs with Non‐SNA nasal disease, and 20 healthy dogs.

Methods

Prospective cross‐sectional study. Aspfum, PanAsp, and PanFun were performed on blindly collected nasal swabs obtained in anesthetized dogs.

Results

In SNA dogs, Aspfum and PanAsp were positive in 13/20 and 14/20 dogs. In all dogs in the 3 other groups, A. fumigatus DNA was not detected using Aspfum. PanAsp was positive in 3 non‐SNA dogs: 1 with cured SNA and 2 with Non‐SNA nasal disease. A Ct cut‐off value of 33.3 for Aspfum demonstrated 65% sensitivity and 100% specificity. A Ct cut‐off value of 34.5 for PanAsp demonstrated 70% sensitivity and 96.2% specificity. PanFun was positive in 16/20, 12/12, 19/20, and 7/20 dogs in the SNA, cured SNA, Non‐SNA, and healthy groups, respectively.

Conclusion and Clinical Importance

Aspfum and PanAsp on blindly collected nasal swabs can be useful for the detection of SNA at diagnosis and at cure, especially when more invasive methods are not available.

Environmental Factors Shaping the Diversity and Spatial-Temporal Distribution of Indoor and Outdoor Culturable Airborne Fungal Communities in Tianjin University Campus, Tianjin, China

Airborne fungi have significant influence on air quality and may pose adverse effects on human health due to their allergenic and pathogenic effect. We carried out a 1-year survey on the airborne fungal diversity and concentration of indoor and outdoor environments, within the Tianjin University campus. Airborne fungi were sampled using an HAS-100B air sampler. Isolated fungal strains were identified based on morphological and molecular analysis. A total of 641 fungal strains belonging to 173 species and 74 genera were identified in this study. The dominant fungal genera were Cladosporium (29.49%), Alternaria (25.9%), and Epicoccum (6.24%), while the most frequently occurring species were A. alternata (15.44%), C. cladosporioides (11.86%), and E. nigrum (5.77%). The mean fungal concentration at different sites ranged from 0 to 420 CFU/m³, which is lower than the permissive standard level. There was a seasonal variation in the airborne fungal community, while temperature and relative humidity were positively correlated with the fungal concentration and diversity at almost all the sites. Higher fungal diversity was recorded in peak period of human traffic at the two canteens, whereas the two dormitories showed higher fungal diversity in off-peak period. Our study provides the first report on the diversity and concentration of airborne fungal species within different Tianjin University campus environments and clarifies the role played by environmental factors on the analyzed fungal community. Our results may represent valuable information for air quality monitoring and microbial pollution control in densely populated human living environments.

Two new species of Cladosporium from leaf spots of Parispolyphylla in north-western Yunnan Province, China

Background

During the survey of pathogenic fungi on medicinal plant leaves in Yunnan Province, China, two Cladosporium-like taxa were isolated from leaf spots of Parispolyphylla. Based on morphological characteristics and phylogenetic analysis of combined ITS, TEF1-α and ACT genes, two new species were discovered.

New information

Two new species Cladosporiumyunnanensis and C.paris are introduced, the detailed descriptions and illustrations are provided. Morphology of the two new species is compared with other related Cladosporium species. This study widens the host diversity of the genus Cladosporium.

Analysis of culturable airborne fungi in outdoor environments in Tianjin, China

Background

Fungal spores dispersed in the atmosphere may become cause of different pathological conditions and allergies for human beings. A number of studies have been performed to analyze the diversity of airborne fungi in different environments worldwide, and in particular in many urban areas in China. We investigated, for the first time, the diversity, concentration and distribution of airborne fungi in Tianjin city. We sampled 8 outdoor environments, using open plate method, during a whole winter season. Isolated fungi were identified by morphological and molecular analysis. Environmental factors which could influence the airborne fungi concentration (temperature, humidity, wind speed, and air pressure) were monitored and analyzed. The effect of different urban site functions (busy areas with high traffic flow and commercial activities vs. green areas) on airborne fungal diversity was also analyzed.

Results

A total of 560 fungal strains, belonging to 110 species and 49 genera of Ascomycota (80 %), Basidiomycota (18 %), and Mucoromycota (2 %) were isolated in this study. The dominant fungal genus was Alternaria (22 %), followed by Cladosporium (18.4 %), Naganishia (14.1 %), Fusarium (5.9 %), Phoma (4.11 %), and Didymella (4.8 %). A fungal concentration ranging from 0 to 3224.13 CFU m^− 3 was recorded during the whole study. Permutational multivariate analysis showed that the month was the most influential factor for airborne fungal community structure, probably because it can be regarded as a proxy of environmental variables, followed by wind speed. The two analyzed environments (busy vs. green) had no detectable effect on the air fungal community, which could be related to the relatively small size of parks in Tianjin and/or to the study season.

Conclusions

Our study shed light on the highly diverse community of airborne fungi characterizing the outdoor environments of Tianjin, and clarified the role that different environmental factors played in shaping the analyzed fungal community. The dominant presence of fungi with potential hazardous effect on human health, such as Alternaria, Cladosporium and Naganishia, deserves further attention. Our results may represent a valuable source of information for air quality monitoring, microbial pollution control, and airborne diseases prevention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02205-2.

Fecal Fungi Dysbiosis in Nonalcoholic Fatty Liver Disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) can systematically harm more aspects of human health than just the liver. In addition to the potential roles of the gut microbiota in NAFLD, commensal fungi can functionally replace intestinal bacteria in maintaining the host immune response in the gut by reversing disease susceptibility. Therefore, gut commensal fungi should be studied to help understand NAFLD.

METHODS

The fungal compositions of 79 patients with NAFLD and 34 matched healthy subjects were studied via internal transcribed spacer sequencing. In the NAFLD group, 32 patients underwent liver biopsies to evaluate the associations between gut fungi and NAFLD development.

RESULTS

The fungal microbiota distribution was skewed in the patients with NAFLD. The relative abundances of Talaromyces, Paraphaeosphaeria, Lycoperdon, Curvularia, Phialemoniopsis, Paraboeremia, Sarcinomyces, Cladophialophora, and Sordaria were higher in patients with NAFLD, whereas the abundances of Leptosphaeria, Pseudopithomyces, and Fusicolla were decreased. Patients with NAFLD exhibited more co-occurring fungal intrakingdom correlations. Several fungi were found to be associated with liver injury, lipid metabolism, and the development of NAFLD.

CONCLUSIONS

This study found that gut fungi may play some roles in NAFLD development. Research on gut fungi may be of great value in diagnosing and monitoring NAFLD.

Upper digestive tract abnormalities in dogs with chronic idiopathic lymphoplasmacytic rhinitis

BACKGROUND

Chronic idiopathic lymphoplasmacytic rhinitis (CILPR) is a common inflammatory disorder of unknown etiology affecting the nasal cavity of dogs. The diagnosis is made by exclusion of other causes of nasal disease and specific therapeutic protocols are lacking. In human medicine, a relationship between CILPR and gastrointestinal clinical signs has been postulated, and remission of respiratory signs after clinical trials with medications for gastrointestinal disorders has been observed.

OBJECTIVES

To describe history, clinical presentation, endoscopic and histopathologic concurrent respiratory and digestive tract abnormalities, and to evaluate improvement of respiratory signs after treatment for gastrointestinal signs.

ANIMALS

Twenty-five dogs with CILPR.

METHODS

Prospective study. For inclusion, following information had to be available: respiratory and digestive clinical signs, airway and digestive tract endoscopic abnormalities, histologic evaluation of respiratory and gastrointestinal tract biopsy specimens, and clinical response to different treatment strategies.

RESULTS

Twenty-two dogs had endoscopic gastrointestinal lesions, whereas 13 dogs had concurrent gastrointestinal signs. Most esophageal and duodenal endoscopic abnormalities were classified as moderate or severe. Respiratory and gastrointestinal tract histologic evaluation identified mostly chronic inflammation. Remission or marked improvement of respiratory signs was observed in the majority of dogs treated only for gastrointestinal signs up to 12 months after endoscopy. No significant associations between treatments and follow-up information were found.

CONCLUSION AND CLINICAL IMPORTANCE

Nasal and upper digestive tract abnormalities coexist in some dogs with CILPR. Lack of standardized therapeutic protocols suggests caution when interpreting improvement in nasal clinical signs. Additional studies are needed to explore the possibility of a cause-effect relationship between the 2 processes.

Dermatophytosis: Prevalence of Dermatophytes and Non-Dermatophyte Fungi from Patients Attending Arsho Advanced Medical Laboratory, Addis Ababa, Ethiopia

BACKGROUND

Dermatophytosis is a disease of major public health problem around the globe causing a considerable morbidity.

OBJECTIVE

To study the prevalence of dermatophytosis and the spectrum of fungi implicated in causing the infection.

METHODS

Nail, skin, and scalp scrapings were collected from 318 patients and were used for microscopy and culture study. Fungal pathogens were identified by studying the macroscopic and microscopic characteristics of their colonies.

RESULT

Tinea capitis was the predominant clinical manifestation consisting of 48.1% of the cases. Among 153 patients with tinea capitis, 73.2% were in the age group of 1-14 years. Of 318 study participants, 213 (67.98%) were found to be positive for dermatophytosis microbiologically. Out of 164 fungal isolates, 86 were dermatophytes and 78 were non-dermatophyte fungi. Among 86 dermatophytes, T. violaceum represented 38.4% of dermatophyte isolates and 89.7% of the isolates were recovered from tinea capitis. Of 76 non-dermatophyte molds, Aspergillus spp., Scytalidium dimidiatum, and Cladosporium spp. were the most common isolates, respectively.

CONCLUSIONS

Failure to detect or isolate fungal pathogens in a large number of clinical samples revealed the limitation of clinical diagnosis in differentiating dermatophytosis from other skin infections demonstrating that clinical diagnosis should be coupled with laboratory methods. Recovery of large number of non-dermatophyte fungi along with dermatophytes in our study showed that non-dermatophyte fungi are emerging as important causes of dermatophytosis, warranting the implementation of intensive epidemiological studies of dermatophytosis across the country.

The evaluation of three treatment protocols using oral prednisone and oral meloxicam for therapy of canine idiopathic lymphoplasmacytic rhinitis: a pilot study

Background

Idiopathic lymphoplasmacytic rhinitis (LPR) is a common inflammatory disorder of the nasal cavity in dogs due to unknown etiology. It is characterised by non-specific clinical signs, including nasal discharge, epistaxis and breathing problems. Diagnosis is usually based on the histopathologic identification of infiltrating plasmocytes and lymphocytes in the nasal mucosa and the exclusion of other underlying diseases. Treatment strategies include glucocorticoids, non-steroidal anti-inflammatory drugs, antibiotics and antifungal medications. The aim of this study was to evaluate the efficacy of various therapeutic protocols for managing canine lymphoplasmacytic rhinitis based on the results of clinical, endoscopic and histological examinations, and to determine the relapse rate for LPR in dogs.

Twenty dogs of different breeds and both sexes, aged 1 to 14 years, were divided into four groups, each consisting of five dogs, including three experimental groups diagnosed with LPR and a control group.

The dogs from the first experimental group were administered prednisone orally at 1 mg/kg/day in the first 4 weeks and 0,5 mg/kg/day in the following 2 weeks. The second group of dogs was administered meloxicam orally at 0,1 mg/kg/day in the first 3 weeks, followed by prednisone at 1 mg/kg/day in the following 2 weeks and 0,5 mg/kg/day in the last week of the treatment. The dogs from the third experimental group were administered meloxicam orally at 0,1 mg/kg/day for 6 weeks. The control group of dogs was administered empty gelatin capsules (placebo) orally for 6 weeks. Clinical signs, endoscopic and histopathologic lesions were scored before and after treatment. Groups were compared using Chi- squared statistics in a 2 × 2 table for pre- versus post-treatment scores.

Results

Clinical signs persisted in the group treated with meloxicam and were mostly resolved in prednisone-treated dogs. However, endoscopic and histological changes were still observed in these two groups after treatment. The severity of all diagnostic features was reduced in the group treated with meloxicam for 3 weeks followed by prednisone for 3 weeks. The significant differences (p < 0.05) were noted between experimental and control groups. The dogs showed a statistically significant reduction in characteristics of the LPR before and after treatment, as measured by clinical signs (Group 1vs.4 p = 0.00, group 2 vs 4 p = 0.00, group 3 vs 4 p = 0,01), by endoscopy (1 vs 4 p = 0,01, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03), and by histopathology (groups 1 vs 4 p = 0,00, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03). The significant differences were noted between experimental groups, as measured by endoscopy (group 2vs 3 p = 0,04), and by relapse rate (groups 1 and 2 p = 0,03, groups 2 and 3 p = 0,01).

Conclusions

The three treatment protocols administered to dogs improved clinical, endoscopic and histological status. However, oral administration of meloxicam for 3 weeks, followed by prednisone for 3 weeks, appeared to be the most successful treatment. These patients remained asymptomatic for 6 months.

Fecal Bacteriome and Mycobiome in Bats with Diverse Diets in South China

Bats can be divided into frugivory, nectarivory, insectivory, and sanguivory based on their diets, and are therefore ideal wild animal models to study the relationship between diets and intestinal microflora. Early studies of bat gut bacteria showed that the diversity and structure of intestinal bacterial communities in bats are closely related to dietary changes. Worthy of note, intestinal microbes are composed of bacteria, fungi, protozoa, and archaea. Although the number of gut fungi is much lower than that of gut bacteria, they also play an important role in maintaining the host homeostasis. However, there are still few reports on the relationship between the gut mycobiota and the dietary habits of the host. In addition, bats have also been shown to naturally transmit pathogenic viruses and bacteria through their feces and saliva, but fungal infections from bat are less studied. Here, we used high-throughput sequencing of bacterial 16S and eukaryotic 18S rRNA genes in the V4 and V9 regions to characterize fecal bacterial and fungal microbiota in phytophagous and insectivorous bats in South China. The results show that the gut microbiota in bats were dominated by bacterial phyla Proteobacteria, Firmicutes, Tenericutes and Bacteroidetes, and fungal phyla Ascomycota and Basidiomycota. There was a significant difference in the diversity of bacterial and fungal microbiota between the groups, in addition to specific bacteria and fungi populations on each of them. Of note, the number of fungi in the feces of herbivorous bats is relatively higher. Most of these fungi are foodborne and are also pathogens of humans and other animals. Thus, bats are natural carriers of fungal pathogens. The current study expands the understanding of the bat gut bacterial and fungal mycobiota and provides further insight into the transmission of fungal pathogens.

Suspect Odontogenic Infection Etiology for Canine Lymphoplasmacytic Rhinitis

The role of odontogenic infection as an etiology for lymphoplasmacytic rhinitis in dogs was evaluated. An association between odontogenic infection and inflammatory rhinitis was identified in 55% of cases evaluated. Odontogenic infection was unlikely or undetermined in 10% and 35% of the cases, respectively. Cases of lymphoplasmacytic rhinitis had roentgen signs associated with endodontic disease, periodontal disease, or retained tooth roots in 60%, 45%, and 25% of the cases, respectively. A collaborative team based approach assessing inflammatory nasal disease is recommended. Based on the history and signalment of the individual patient, diagnostic modalities should be chosen wisely. In some cases, oral examination and intraoral radiographs may be a more direct and cost effective approach for diagnosis and treatment of inflammatory rhinitis.

Cladosporium Species Recovered from Clinical Samples in the United States

Cladosporium species are ubiquitous, saprobic, dematiaceous fungi, only infrequently associated with human and animal opportunistic infections. We have studied a large set of Cladosporium isolates recovered from clinical samples in the United States to ascertain the predominant species there in light of recent taxonomic changes in this genus and to determine whether some could possibly be rare potential pathogens. A total of 92 isolates were identified using phenotypic and molecular methods, which included sequence analysis of the internal transcribed spacer (ITS) region and a fragment of the large subunit (LSU) of the nuclear ribosomal DNA (rDNA), as well as fragments of the translation elongation factor 1 alpha (EF-1α) and actin (Act) genes. The most frequent species was Cladosporium halotolerans (14.8%), followed by C. tenuissimum (10.2%), C. subuliforme (5.7%), and C. pseudocladosporioides (4.5%). However, 39.8% of the isolates did not correspond to any known species and were deemed to comprise at least 17 new lineages for Cladosporium. The most frequent anatomic site of isolation was the respiratory tract (54.5%), followed by superficial (28.4%) and deep tissues and fluids (14.7%). Species of the two recently described cladosporiumlike genera Toxicocladosporium and Penidiella are reported for the first time from clinical samples. In vitro susceptibility testing of 92 isolates against nine antifungal drugs showed a variety of results but high activity overall for the azoles, echinocandins, and terbinafine.

Pollen Allergies in Humans and their Dogs, Cats and Horses: Differences and Similarities

Both humans and their most important domestic animals harbor IgE and a similar IgE receptor repertoire and expression pattern. The same cell types are also involved in the triggering or regulation of allergies, such as mast cells, eosinophils or T-regulatory cells. Translational clinical studies in domestic animals could therefore help cure animal allergies and at the same time gather knowledge relevant to human patients. Dogs, cats and horses may spontaneously and to different extents develop immediate type symptoms to pollen allergens. The skin, nasal and bronchial reactions, as well as chronic skin lesions due to pollen are in principle comparable to human patients. Pollen of various species most often causes allergic rhinitis in human patients, whereas in dogs it elicits predominantly eczematous lesions (canine atopic dermatitis), in horses recurrent airway obstruction or hives as well as pruritic dermatitis, and in cats bronchial asthma and so-called cutaneous reactive patterns (eosinophilic granuloma complex, head and neck pruritus, symmetric self-induced alopecia). In human allergy-specific IgE detection, skin tests or other allergen provocation tests should be completed. In contrast, in animals IgE and dermal tests are regarded as equally important and may even replace each other. However, for practical and economic reasons intradermal tests are most commonly performed in a specialized practice. As in humans, in dogs, cats and horses allergen immunotherapy leads to significant improvement of the clinical symptoms. The collected evidence suggests that canines, felines and equines, with their spontaneous allergies, are attractive model patients for translational studies.