25 Chrysosporium Dongyou Liu and R.R.M. Paterson contents 25.1 Introduction ..................................................................................................................................................................... 197 25.1.1 Classification and Morphology ............................................................................................................................ 197 25.1.2 Clinical Features .................................................................................................................................................. 198 25.1.3 Diagnosis ............................................................................................................................................................. 199 25.2 Methods ........................................................................................................................................................................... 199 25.2.1 Sample Preparation .............................................................................................................................................. 199 25.2.2 Detection Procedures ........................................................................................................................................... 199 25.3 Conclusion .......................................................................................................................................................................200 References .................................................................................................................................................................................200 25.1 IntroductIon thermophilum (→ Myceliophthora thermophila) [6]. Not dis- cussed here are Chrysosporium parvum (or Chrysosporium 25.1.1 ClassifiCation and Morphology parvum var. parvum) and Chrysosporium parvum var. cre­ The genus Chrysosporium (obsolete synonym: Gleno­ scens, which are considered as synonymous for Emmonsia sporella) belongs to the mitosporic Onygenales group, parva and Emmonsia crescens, respectively. To simplify the order Onygenales, class Eurotiomycetes, subphylum presentation and reduce confusion, this chapter focuses on Pezizomycotina, phylum Ascomycota, and kingdom Fungi. Chrysosporium spp. that are keratinophilic, causing subcuta- The mitosporic Onygenales group consists of nine genera: neous infections, whereas Chapter 29 deals with Emmonsia Blastomyces, Chrysosporium, Coccidioides, Emmonsia, spp. that mainly cause pulmonary adiaspiromycosis. Geomyces, Locazia, Malbranchea, Myriodontium, and Chrysosporium colonies grow moderately at 25°C, and AQ1 Paracoccidioides. In turn, the genus Chrysosporium is may appear granular, woolly, or cottony, flat, or raised, and separated into 28 recognized species: Chrysosporium folded. Colonies are white cream, yellow, or tan to pale brown articulatum, Chrysosporium carmichaelii, Chrysosporium on the front, and white to brown on the reverse. Hyphae are chiropterorum, Chrysosporium europa, Chrysosporium septate. Conidia (aleuriconidia) are hyaline, broad based, one evolceanui, Chrysosporium filiforme, Chrysosporium flu­ celled, and smooth or rough walled. Conidia are broader than viale, Chrysosporium fluviale, Chrysosporium indicum, vegetative hyphae and occur terminally on pedicels, along Chrysosporium keratinophilum, Chrysosporium lobatum, the sides of the hyphae, or in intercalary positions. Conidia Chrysosporium lucknowense, Chrysosporium mephiticum, usually have an annular frill that is the remnant of the Chrysosporium merdarium, Chrysosporium minutispo­ hyphal wall that remains after detachment from the hypha. rosum, Chrysosporium ophiodiicola, Chrysosporium Arthroconidia are abundant and larger than parent hyphae pannicola, Chrysosporium pilosum, Chrysosporium in diameter. pseudomerdarium, Chrysosporium queenslandicum, C. tropicum colonies are moderately fast growing, flat, Chrysosporium siglerae, Chrysosporium submersum, white to tan to beige, often with a powdery or granular sur- Chrysosporium sulfureum, Chrysosporium synchronum, face texture. Reverse pigment is absent or pale brownish Chrysosporium tropicum, Chrysosporium undulatum, yellow with age. Ameroconidia are hyaline, one celled, and Chrysosporium vallenarense, Chrysosporium xerophilum, produced directly on vegetative hyphae by nonspecialized and Chrysosporium zonatum, and 18 unassigned species conidiogenous cells. Conidia (6–7 μm × 3.5–4 μm) are typi- [1–3]. The teleomorphs of Chrysosporium spp. are found in cally pyriform to clavate with truncate bases and are formed the genera Aphanoascus, Nannizziopsis, and Uncinocarpus, either intercalary (arthroconidia), laterally (often on pedi- family Onygenaceae, and order Onygenales [4,5]. cels), or terminally. The obsolete species in the genus include Chrysosporium Chrysosporium zonatum (synonym: C. gourii; teleo- dermatitidis (→ Blastomyces dermatitidis), Chrysosporium morph: Uncinocarpus orissi) colonies on potato dextrose pannorum (→ Geomyces pannorus), Chrysosporium pru­ agar (PDA) at 37°C are flat and coarsely powdery, and appear AQ2 inosum (→ Sporotrichum pruinosum), and Chrysosporium yellowish white initially but darken by 14–21 days to buff 197 K10626_C025.indd 197 1/20/2011 8:07:35 AM 198 Molecular Detection of Human Fungal Pathogens (grayish or brownish orange) with a light brown reverse. colonies are similar to those on PCA, with a very restricted Colony topography and color on PDA are similar at 37°C and growth at 15°C (5 mm in diameter in 14 days). At 37°C, there 25°C, but darkening of the colony obverse and growth rate is no growth. Colonies produce a strong, pungent (skunk-like) are slightly faster at 37°C (73 mm in diameter after 14 days) odor after 1 month of incubation in all the media tested. The than at 25°C (66 mm in diameter). Microscopically, the fun- fungus shows a strong keratinolytic activity. Phenotypically, gus forms solitary aleurioconidia that are borne at the ends of C. ophiodiicola is separated from the Chrysosporium ana- short, typically curved stalks or that are sessile (borne on the morph of Nannizziopsis vriesii by the absence of asperulate sides of the hyphae). Conidia (3.5–13 μm × 2.5–5 μm) are sin- fertile hyphae and globose-to-pyriform conidia sometimes gle celled, rarely two celled, smooth to slightly roughened, grouped in clusters and the presence of an odor in the colo- and clavate (club shaped) to broadly obovoid (egg shaped) nies by C. ophiodiicola [3]. and have a rounded tip and a broad, flat basal scar. Intercalary Chrysosporium species are differentiated from each other arthroconidia may be formed but are uncommon. Racquet by the texture of the colony and morphology, location, and size hyphae (hyphae showing swellings near the septa) are com- of the conidia. Chrysosporium zonatum differs from other mon [4]. The teleomorph of Chrysosporium zonatum is a members of the genus Chrysosporium by its faster growth heterothallic ascomycete Uncinocarpus orissi (synonyms, at 37°C than at 25°C and by forming darken to buff colo- Pseudoarachniotus orissi and Gymnoascus arxii) (fam- nies, and clavate, broadly truncate aleurioconidia typically ily Onygenaceae). U. orissi ascocarps are solitary, globose, borne on short, curved stalks. Chrysosporium queenslandi­ and reddish brown and are composed of pale reddish brown cum (teleomorph: Uncinocarpus queenslandicus, or Apinisia ascospores surrounded by thin-walled hyaline racket hyphae queenslandica and Brunneospora reticulata) is similar, but and conidia. Pairing of C. zonatum with U. orissi produces its colonies do not darken, and intercalary arthroconidia are ascoma-containing ascospores that are oblate (like flattened common [4]. disks) with truncate ends and appear smooth to slightly pitted C. ophiodiicola is separated from C. mephiticum by the (punctate) [4]. narrow, cylindrical-to-slightly clavate conidia of C. ophio­ Chrysosporium ophiodiicola colonies attain diameters of diicola, and the pyriform-to-subglobose conidia of C. 27–29 mm in 14 days at 25°C on potato carrot agar (PCA; mephiticum; C. ophiodiicola is differentiated from A. mephi­ 20 g potato, 20 g carrot, 15 g agar, 1 L water). Colonies are talis by the production of teleomorph during the culture of white from front and uncolored on reverse, felty, plane, A. mephitalis; and C. ophiodiicola is distinguished from and fimbriate, with a poorly defined margin. Sparse tufts Chrysosporium europae by the characteristic vinaceous, of aerial mycelium are present on the submarginal zone. buff-pigmented colonies on phytone-yeast extract agar and Vegetative hyphae (1.5–2.5 μm wide) are hyaline, branched, the absence of a strong, pungent odor of/from C. europae. septate, smooth, and thin walled. They are often disarticu- Some species such as Chrysosporium pannicola do not grow lated at maturity to form cylindrical arthroconidia (7.5– at 37°C. Chrysosporium differs from Blastomyces by being 10 μm × 2–3 μm) adjacent to each other. Fertile hyphae arise nondimorphic, from Microsporum and Trichophyton by as lateral branches. Terminal and lateral conidia are borne lacking macroconidia, from Geomyces by lacking branched, on straight or flexuous side branches of variable length (4.5– fertile hyphae on erect conidiophores, and from Sepedonium 16 μm) or are sometimes sessile. Conidia (4–9 μm × 2–3 μm) by having hyaline conidia. are unicellular, solitary, thin walled, smooth, hyaline to pale yellow, and cylindrical to slightly clavate and are released 25.1.2 CliniCal features by