DESCRIPTIONS OF MEDICAL FUNGI

Descriptions of Medical Fungi 49
Candida rugosa complex
Candida rugosa has recently been recognised as a species complex of C. rugosa, C.
pseudorugosa and another as yet undescribed species (Li et al. 2006, Paredes et al.
2012). These species are best identified by ITS sequencing.
RG-1 organism.
Candida rugosa (Anderson) Diddens & Lodder
Culture: Colonies (SDA) white to cream-coloured smooth, glabrous, yeast-like.
Microscopy: Ellipsoidal to elongate budding blastoconidia, 5-11 x 1.5-2.5 µm.
Sometimes short pseudohyphae may be produced.
India Ink Preparation: Negative - no capsules present.
Dalmau Plate Culture: Densely branched pseudohyphae produced.
Physiological Tests: + Positive, - Negative, v Variable, w Weak, s Slow
Germ Tube - L-Sorbose v L-Arabinose - D-Glucitol v
Fermentation Sucrose - D-Arabinose - α-M-D-glucoside -
Glucose - Maltose - D-Ribose - D-Gluconate v
Galactose - Cellobiose - L-Rhamnose - DL-Lactate v
Sucrose - Trehalose - D-Glucosamine - myo-Inositol -
Maltose - Lactose - N-A-D-glucosamine + 2-K-D-gluconate -
Lactose - Melibiose - Glycerol + D-Glucuronate -
Trehalose - Raffinose - Erythritol - Nitrate -
Assimilation Melezitose - Ribitol - Urease -
Glucose + Soluble Starch - Galactitol - 0.1% Cycloheximide -
Galactose + D-Xylose + D-Mannitol v Growth at 37 O C +
Key Features: Germ tube negative yeast and sugar assimilation pattern (D-Xylose
and Glycerol +ve; Ribitol -ve.). C. rugosa has been associated with catheter related
fungaemia and has been isolated from human and bovine faeces, sea water and soil.
Antifungal Susceptibility: C. rugosa limited data (Diekema et al. 2009, Espinel-
Ingroff et al. 2014 and Australian National data); MIC µg/mL.
No 64
AmB 21 1 1 5 5 7 1 1
FLU 97 1 3 15 24 29 8 8 6 1 2
VORI 80 4 8 38 16 4 7 3
POSA 66 1 4 12 27 9 8 5
ITRA 5 1 1 1 1 1
ANID 20 3 4 4 4 3 2
MICA 20 2 3 5 6 2 2
CAS 25 1 1 2 3 10 1 1 2