DESCRIPTIONS OF MEDICAL FUNGI

Descriptions of Medical Fungi 143
Ochroconis de Hoog and Arx
Recently, the genus Ochroconis has undergone taxonomic revision, and the most
relevant species, Ochroconis gallopava, was transferred to the new genus Verruconis
(Samerpitak et al. 2014). Ochroconis species are mesophilic saprobes, with an
optimum growth temperature between 15 and 30 O C and an inability to grow at 37 O C.
Nevertheless, some species have been isolated from clinical specimens; such as
Ochroconis tshawytschae, O. mirabilis, O. cordanae, O. olivacea and O. ramosa
(Samerpitak et al. 2014, Seyedmousavi et al. 2014, Giraldo et al. 2014). Note: Species
described in the literature from clinical cases as O. constricta or O. humicola are
probably O. musae (Samerpitak et al. 2014).
Giraldo et al. (2014) reported on the occurrence of Ochroconis and Verruconis species in
clinical specimens from the United States. V. gallopava was the most common species
(69%), followed by O. mirabilis (22%). Other species isolated were O. cordanae, O.
olivacea and O. ramosa. The most common anatomical site of isolation was the lower
respiratory tract (59%), followed by superficial (22%) and deep tissues (20%) (Giraldo
et al. 2014).
RG-1 organisms.
Morphological Description: Colonies restricted, velvety to funiculose, brown to
olivaceous, often with rust-brown reverse. Hyphae smooth- or somewhat rough-walled,
pale olivaceous. Conidiophores slightly or conspicuously differentiated, cylindrical,
often flexuose, producing conidia on scattered, cylindrical to conical denticles. After
detachment an inconspicuous frill often remains both on the denticle and on the
conidium base. Conidia one to four-celled, pale olivaceous brown, smooth- or roughwalled,
ellipsoidal, cylindrical, clavate or cuneiform. Maximum growth temperature
around 33 O C.
Molecular Identification: Giraldo et al. (2014) used sequence analyses of the 18S,
ITS, D1/2, actin, and β-tubulin genes, while Seyedmousavi et al. (2014), used ITS
sequence analyses to identify species.
References: de Hoog et al. (2015), Samerpitak et al. (2014), Seyedmousavi et al.
(2014), Giraldo et al. (2014).
Antifungal Susceptibility: Ochroconis mirabilis variable data for posaconazole,
caspofungin and anidulafungin from Seyedmousavi et al. (2014) 1 and Giraldo et al
(2014) 2 ; MIC µg/mL.
Antifungal Range MIC 90
Antifungal Range MIC 90
0.06-0.25
AmB 1-32 32 POSA
1 -
0.5-32 2 32
ITRA 0.25-32 32 VORI 2-32 32
CAS
0.5-1 1
1-32 2 -
4
ANID
0.03-0.125 1
0.015-32 2 -
4
MICA 0.06-0.50 0.25 TERB 0.015-0.125 0.02