Mycology

Colony Picker: Principle, Protocol, and Advantages 

Automated colony pickers are the equipment that helps pick the desired colony from a cluster of different colonies from any culture media.

Automated Culture Media Preparation and Dispenser System

Automated culture media preparation and dispenser system is a way of applying modern technology for making isolation of microorganisms easy.

Rhizopus and Mucor: Characteristics and Diagnosis

Rhizopus and Mucor are saprophytic molds but can cause mucormycosis (zygomycosis, phycomycosis) in immunocompromised individuals. 

Czapek Dox Agar: Principle, Composition, Colony Characteristics

Czapek medium is also called Czapek’s agar (CZA) or Czapek-Dox medium. It is used to isolate the Aspergillus, Penicillium, Paecilomyces, and other fungi

Galactomannan Test for Invasive Aspergillosis

In person with invasive aspergillosis, there may be high titers of galactomannan antigen in serum and bronchoalveolar lavage (BAL) fluid.

Mycosis: Etiology, Types, and Classification

Mycoses can be classified based on the site of the infection, route of acquisition of the pathogen, and type of virulence exhibited by the fungi.

Candida auris: Transmission, Risk, Diagnosis, Treatment

Candida auris causes a serious and sometimes fatal fungal infection that is emerging globally. Identification of C. aurius is challenging.

Laboratory Diagnosis of Mucormycosis

Mucormycosis caused by Mucorales can be diagnosed by histopathological examination with or without isolation of the fungus from the same site.

Mucormycosis: Pathogenesis, Clinical Features, and Treatment

Mucormycosis (zygomycosis, phycomycosis) is caused by saprophytic molds (e.g., Mucor, Rhizopus, and Absidia).

Sample Collections for Lab Diagnosis of Fungal Infections

Hair, nail clippings, skin scrapings, blood, CSF, and sputum are the most common clinical specimens.

Dermatophyte Test Medium (DTM): Composition, Preparation, Uses

Dermatophyte test medium (DTM) is a specialized selective and differential fungal cultures medium to isolate and identify dermatophytes.

Blastomyces dermatitidis: Pathogenesis, Lab Diagnosis

Blastomyces dermatitidis is a thermally dimorphic fungus and causes blastomycosis. Single broad-based bud in a clinical sample is diagnostic.

Slide Culture for Fungi: Principle, Procedure, Results

Slide-culture is a rapid method of preparing fungal colonies for examination and identification with little disturbance as possible.

Pneumocystis jirovecii: Properties, Pathogenesis, Lab Diagnosis

Pneumocystis jirovecii is an opportunistic atypical fungal pathogen which does not respond to conventional anti-fungal agents.

Antigens in disease diagnosis

Detection of specific antigens present in the sample (blood, urine, or CSF) using specific antibodies is the mainstay for the rapid diagnosis of infections.

Aspergillus fumigatus: Morphology, Pathogenesis, Lab Diagnosis

Aspergillus fumigatus is a mold with a septate hyphae with acute angle branching. It causes infections of the skin, eyes and ears; fungus ball in the lungs.

Laboratory diagnosis of Fungal Infections

Culture, direct microscopy, and histopathology are mostly used methods for the diagnosis of fungal infections.

Bird Seed Agar: Composition, Uses

Bird Seed Agar is a solid medium used for selective and differential isolation of Cryptococcus neoformans from clinical specimens.

Histoplasma capsulatum: Properties, Diseases, Lab Diagnosis

Histoplasma capsulatum is an intracellular, thermally dimorphic fungi. It causes systemic mycoses called histoplasmosis.

Cryptococcus neoformans: Pathogenesis, Lab Diagnosis

Cryptococcus neoformans is an opportunistic fungal pathogen (yeast) responsible for causing cryptococcal meningitis.

KOH Mount: Principle, Procedure, Results, Uses  

KOH preparation is used for the rapid detection of fungal elements in clinical specimens but it may not necessarily identify the species of the fungi.

Candida albicans: Pathogenesis, Diseases, Lab Diagnosis

Causative agents of Candidiasis, Candida albicans is a gram-positive yeast cells. It gives positive germ-tube test.

Germ Tube Test: Principle, Procedure, Results

Germ tube is a short hyphal extension arising laterally from a yeast cell with no constriction at the point of origin.

Sabouraud Agar (SDA): Composition, Uses, Colony Morphology

Originally formulated for dermatophyte growth and pigment production, SDA is used for growth and maintenance of fungi.

Potato Dextrose Agar (PDA): Principle, Composition, Colony Characteristics

Potato Dextrose Agar (PDA) is an ideal medium for slide culture preparation. It promotes sporulation of moulds.

Lactophenol Cotton Blue (LPCB) Mounts

Lactophenol cotton blue solution is a mounting medium and staining agent used in the preparation of slides for microscopic examination of fungi.

Common Fungal Culture Media: Their Uses

Fungal culture media contains high carbohydrate and nitrogen source. They may also contain cycloheximide and antibacterial agents to inhibit contaminants.

Microscopic Identification of Fungi (Yeasts, Molds)

Sporotrichosis (Rose Gardener’s disease) Lab Diagnosis

Sporotrichosis is a chronic infection of subcutaneous tissues caused by a dimorphic fungus, Sporothrix schenckii.

Dimorphic Fungi: Disease, Properties

Dimorphic fungi exist as molds in the environment at ambient temperature and as yeasts in human tissues at body temperature.

Why Epidermophyton does not infect hair?