The dermatophytes
Chapter 38 The dermatophytes The dermatophytes are a group of closely related, septate fungi that require and use keratin for growth. They tend to be confined to the superficial integument…
The Mycoplasmas (class: mollicutes)
Chapter 35 The Mycoplasmas (class: mollicutes) The mollicutes are the smallest procaryotic cells capable of self-replication. The genomes of Mycoplasma and Ureaplasma species may be as small as 600 kb compared…
The streptococci and related cocci
Chapter 8 The streptococci and related cocci Genus Characteristics The streptococci and enterococci are Gram-positive cocci that occur singly, in pairs, or in chains of varying lengths. Each coccus is…
The spirochaetes
Chapter 31 The spirochaetes The order Spirochaetales includes the families Spirochaetaceae, Brachyspiraceae and Leptospiraceae. The genera of significance in animals and humans are Leptospira (Leptospiraceae), Treponema and Borrelia (Spirochaetaceae) and…
Mycobacterium species
Chapter 11 Mycobacterium species Genus Characteristics The mycobacteria usually form thin rods of varying lengths (0.2–0.6 × 1.0–10.0 µm). Sometimes branching filamentous forms occur but these easily fragment into rods. They…
Corynebacterium species and Rhodococcus equi
Chapter 9 Corynebacterium species and Rhodococcus equi Genus Characteristics The Corynebacterium species belong to the Corynebacteriaceae family of the Actinomycetales order. They are small, short, pleomorphic Gram-positive rods (about 0.5 µm…
Serological diagnosis
Chapter 3 Serological diagnosis Serological testing is generally less expensive and easier to perform than the isolation or detection of an infectious agent, particularly virus. Clinicians often request serological screening…
Staphylococcus species
Chapter 7 Staphylococcus species Genus Characteristics The staphylococci are Gram-positive cocci with an average diameter of 0.8 to 1 µm, that tend to be arranged in pairs, tetrads, or more often,…
The isolation of viruses and the detection of virus and viral antigens
Chapter 5 The isolation of viruses and the detection of virus and viral antigens Virus isolation Virus isolation is traditionally the definitive criterion against which other diagnostic methods are assessed….
The pathogenic yeasts
Chapter 40 The pathogenic yeasts Yeasts are common in the environment, often found on plants or associated with plant materials. They are also found as commensals of the skin and…
