Development of Experimental Model of Feline Microsporum Infection (2023)

FAQs

What is the microscopic appearance of Microsporum? ›

Microscopic morphology

Microsporum canis reproduces asexually by forming macroconidia that are asymmetrical, spherically shaped and have cell walls that are thick and coarsely roughened.

Culture of Microsporum canis. Morphological description: Colonies are flat, spreading, white to cream-coloured, with a dense cottony surface which may show some radial grooves. Colonies usually have a bright golden yellow to brownish yellow reverse pigment, but non-pigmented strains may also occur.

Microsporum is a genus of fungi that causes tinea capitis, tinea corporis, ringworm, and other dermatophytoses (fungal infections of the skin). Microsporum forms both macroconidia (large asexual reproductive structures) and microconidia (smaller asexual reproductive structures) on short conidiophores.

Overview: Dermatophytosis, usually caused by Microsporum canis, is the most common fungal infection in cats worldwide, and one of the most important infectious skin diseases in this species. Many adult cats are asymptomatic carriers.

Microscopic morphology

Microsporum ferrugineum produces sterile, septate hyphae which are usually deformed and irregularly branched, having a bamboo-like appearance. Long, straight, thick-walled, hypersegmented hyphae are often present. This Microsporum spp. does not produce macro- and microconidia.

Microsporum canis is part of a family of fungi known as dermatophytes. Microscopically, it has multi- celled spores known as macroconidia with rough thick walls. Macroconidia are characteristically spindle shaped with 5-15 cells.

Diagnosis is via Wood's lamp, skin, and hair cultures. Microscopic examination of hairs taken from the periphery of the lesion and prepared with 10% KOH solution is a quick diagnostic test that may be done on site.

M. canis is known to mainly reproduce asexually through a mitotic process, and the propagules that originate from the asexual reproduction (conidia) vary according to the context in which the fungus is located.

Macroscopic appearance of culture of Microsporum gypseum on Dermasel agar base supplemented with chloramphenicol and cycloheximide: a) flat, granular, with a deep cream to pale cinnamon-colored surface and b) yellow brown reverse pigment.

Microscopically, numerous "small, pear-shaped, thick- walled, finely verrucose or occasionally smooth two- or three-celled macronidia" were formed. These spores had truncate bases and ranged in size from 12-18 X 4-7.5 p.. Microconidia were present in low num- bers in the Sabouraud agar cultures.

Where does Microsporum grow? ›

It belongs to genus Microsporum, family Arthrodermataceae, order Onygenales, class Eurotiomycetes, and division Ascomycota. The fungus has a worldwide distribution, particularly in humid, warm climates like Europe, the eastern Mediterranean, and South America.

Tinea corporis (B35. 6) caused by Microsporum canis which is fungal species that causes numerous forms of disease. It is part of a group of fungi known as Dermatophytes. Though mostly well known for ringworm in pets, it is also known to infect humans.

Miconazole shampoos are most effective when combined with chlorhexidine (see Table 1) [2,24]. Clotrimazole, miconazole, and enilconazole are also recommended for topical treatment of M. canis infections in animals, but not as sole therapy [2].

Approximately 40 different species of fungi can cause ringworm; the scientific names for the types of fungi that cause ringworm are Trichophyton, Microsporum, and Epidermophyton.

Microsporum canis (M. canis) is a pathogenic, highly contagious and asexual fungus of the phylum Ascomycota. M. canis causes infections of the scalp and body sites, creating inflammatory lesions associated with hair loss.

Fungi can be divided into two basic morphological forms, yeasts and hyphae.

The hyphae or appendages are of three kinds in the fungi, the first being straight, slender, smooth walled hyphae that can grow up to 250 μm long; they taper at 2.5–4.0 μm in diameter at the base but close to about 1.5-2 μm.

Transmission occurs via direct contact with an infected animal or person, or by contact with infected hair and scale on fomites or in the environment. T. mentagrophytes and M.

The life cycle of Microsporidia consists of 2 distinct stages which are merogony or the proliferating stage, and sporogony or infecting or mature stage. Briefly, the life cycle of Microsporidia are: Spores enter the host by ingestion and or inhalation.

1. capitalized : a genus of fungi of the family Moniliaceae producing both small, nearly oval single-celled spores and large spindle-shaped multicellular spores with a usually rough outer wall and including several that cause ringworm, tinea capitis, and tinea corporis.

What are fungal microscopic characteristics? ›

Typical hyphal features in higher fungi seen with the ordinary light microscope include cell walls, cross walls or septa, vacuoles, various inclusions such as fat globules and crystals, and occasionally, nuclei. Most fungal nuclei are very small and special stains are often required for observation.

Infection occurs by contact with viable spores from infected hair on infected animals or people, on contaminated fomites (especially tack and grooming equipment), and in contaminated soil. The incubation period is 1–4 wk.

The genus Microsporum is distributed worldwide and M. canis is the most common zoophillic species to affect humans, primarily causing tinea capitis in children. Domestic dogs and cats are usually the reservoir of infection and are often healthy carriers of Microsporum.

Trichophyton rubrum is the most common anthropophilic dermatophyte worldwide and its typical infection areas include skin of hands or feet and nail plate. In turn, Microsporum canis is a zoophilic pathogen, and mostly well known for ringworm in pets, it is also known to infect humans.

Topical antifungal agents

In vitro, econazole inhibits most strains of Trichophyton, Microsporum, and Epidermophyton, C. albicans, and M. furfur. Topical econazole is effective in the treatment of tinea pedis, tinea cruris, and tinea corporis caused by dermatophytes, as well as tinea versicolor caused by M.

Microsporum canis has shown maximum growth at 30°C and high rate of sporulation was observed in a temperature range of 25°C to 35°C.

Microsporum is a filamentous keratinophilic fungus included in the group of dermatophytes. While the natural habitat of some of the Microsporum spp. is soil (the geophilic species), others primarily affect various animals (the zoophilic species) or human (the anthropophilic species).

Microsporum nanum is a mesophile and grows moderately rapid on Sabouraud's Dextrose agar. Its macroconidia are ovoid in shape and, unlike those of most other species of Microsporum, normally consist of no more than three cells. Rare to moderate numbers of rough-walled microconidia can also be found in the colony.

Macroscopic morphology

Microsporum nanum grows moderately rapidly and the diameter of the colony reaches 1 to 3 cm following incubation at 25°C for 7 days on Sabouraud dextrose agar. The texture is powdery, cottony, thin, spreading, velvety or flat and often has some radial, shallow furrows.

[1] It is caused primarily by the dermatophyte species Microsporum and Trichophyton. The fungi can penetrate the hair follicle outer root sheath and ultimately may invade the hair shaft.

Does Microsporum cause nail infection? ›

Nail infections are mainly caused by T. rubrum, followed by T. mentagrophytes (1a, 19, 20, 25, 27, 29), in contrast to hair and skin infections, which may be caused by other dermatophyte species, including Microsporum spp.

Terbinafine. Terbinafine (Lamisil) comes in creams, sprays, and gels and can treat athlete's foot, jock itch, and other ringworm infections on the skin. The CDC says terbinafine seems to be the most effective treatment for tinea pedis.

Antifungal shampoo

A shampoo such as Nizoral or Head and Shoulders Intensive kills ringworm spores. Lather and leave it on your child's scalp for 10Â minutes before rinsing. Use the antifungal shampoo twice a week for 1 month. On other days, use a regular shampoo.

The colonies are flat, dense and cottony in texture with a greyish-white to reddish brown hue. On Potato Dextrose agar, colonies are white with a silky texture and a peach-coloured underside. Microsporum audouinii can be differentiated from non-sporulating strains of the similar M. canis by culture on autoclaved rice.

The genus Trichophyton is characterised morphologically by the development of both smooth-walled macro- and microconidia. Macroconidia are mostly borne laterally directly on the hyphae or on short pedicels, and are thin- or thick-walled, clavate to fusiform, and range from 4-8 x 8-50 μm in size.

Microscopic morphology

Macroconidia are abundant, fusiform and symmetrical in shape with rounded ends. The walls of macroconidia are thin and rough and they contain 3-6 cells. Microconidia are moderately numerous in number, club-shaped and located along the hyphae.

Diagnosis requires microscopic examination of hair and skin samples and dermatophyte culture. For topical therapy, 2% chlorhexidine/2% miconazole shampoo, or 0.2% enilconazole rinse is effective. Topical treatment removes spores from hair shafts, and systemic treatment acts at hair follicles.

Microscopically, M. canis reproduces by means of two conidial form multi-celled macroconidia and single-celled microconidia. The asexual propagation of the fungus is produced through forming asymmetrical, spherically shaped macroconidia.

Formerly, its most common use was in screening patients with alopecia for tinea capitis, as the most common causative organisms, Microsporum audouinii and other Microsporum species, were easily identified by blue-green fluorescence under Wood light.

The macroscopic features of common mold that are multicellular fungi may include colonial form by its cottony appearance, surface color, and presence of pigments. The microscopic features include hyphae and mycelium forming a thallus; hyphae can be categorized into septate and aseptate hyphae.

What are three types of macroscopic fungi? ›

Macroscopic fungi such as morels, mushrooms, puffballs, and the cultivated agarics available in grocery stores represent only a small fraction of the diversity in the kingdom Fungi.