is a cosmopolitan
filamentous fungus that thrives in soil, plant material, feathers, and
insects. Scopulariopsis species, aside from being considered as
contaminants, are agents of infections in humans, particularly in
immunocompromised patients. Certain Scopulariopsis species attack
bee larvae and silkworms as well. Additionally, Scopulariopsis is
a weakly keratinolytic fungus which is highly resistant to benomyl.
Several species of Scopulariopsis have
teleomorphs which are placed
under the genus Microascus.
Scopulariopsis is distinctive as it contains both moniliaceous
(hyaline) and dematiaceous species, wherein some are considered as
clinically important. The most common is Scopulariopsis brevicaulis
which is a hyaline fungus. Other hyaline species include
Scopulariopsis candida, which maintains its white color at maturity
rather than becoming buff - colored, Scopulariopsis koningii,
Scopulariopsis acremonium, and Scopulariopsis flava.
Dematiaceous species include Scopulariopsis cinerea which is the
anamorph of Microascus cirrosus, Scopulariopsis brumptii,
Scopulariopsis chartarum, Scopulariopsis fusca, and
Pathogenicity and Health Effects
species is rarely a cause of human infection.
Onychomycosis especially of
the toe nails by Scopulariopsis is occasionally reported. Skin
lesions, brain abscess,
sinusitis, and disseminated infections due to
Scopulariopsis species have been rarely reported. Infections caused
by Scopulariopsis are observed mainly in immunocompromised patients
such as bone marrow transplant recipients.
with human deaths by producing arsine gas from arsenate dyes found in wall
paper is considered as one of the striking features of Scopulariopsis
brevicaulis. Volatilization and methylation of dimethylarsinic acid
and methylation of arsenate and arsenite naturally occur in soil. These
biochemical reactions have production of trimethylarsine and
dimethylarsine as the end - products. Arsenic is found in pesticides as
is the most toxic
form of arsenic. It gives off garlic – like odor at concentrations above
0.5 ppm and it is still toxic at concentrations even lower than 0.5 ppm.
In the 1810s,
arsenate dyes were manufactured and incorporated into wallpapers and the
most famous was Schweinfurter green.
The widespread use of these green – colored wallpapers has led to the
illnesses, such as tubular necrosis and renal failure, and death of people
who slept in green wall – papered rooms. Emission of garlic – like odor
in some rooms was noted as well. In 1897, B. Gosio, an Italian chemist,
showed that the cause of the deaths was due to the production of a gas
which could not be identified at that time thus, led to the so – called
Gosio gas. Then in 1945, Frederick Challenger was able to
identify the gas as trimethylarsine which was produced by the mold fungus
Penicillium brevicaulum which is known today as Scopulariopsis
brevicaulis. Scopulariopsis brevicaulis consumes the starch
found in the wallpaper paste while it converts the arsenate found in the
paper to trimethylarsine oxide. Lastly, this oxide is further reduced
into the fatal and death – causing trimethylarsine gas which is then
released. Though this phenomenon was primarily linked only to
Scopulariopsis brevicaulis, other molds present in the environment may
also be able to discharge volatile arsenic compounds theoretically by
using the same mechanism.
dematiaceous Scopulariopsis species are also clinically significant
which include the Scopulariopsis cinerea, the anamorph of
Microascus cinereus, which has been reported as the causative agent in
human nail infection, in maxillary sinusitis co – existing with
Aspergillus repens, cutaneous granulomata in a patient with chronic
granulomatous disease, endocarditis of a prosthetic valve implanted
following the staphylococcal endocarditis of a native valve, and a brain
abscess in a bone marrow transplant recipient. The anamorph of
Microascus trigonosporus, Scopulariopsis trigonospora,
is an agent of fatal pneumonia in a bone marrow transplant patient.
Additionally, the dematiaceous Scopulariopsis anamorph of
Microascus cirrosus is an agent of
onychomycosis and disseminated infection in a pediatric bone marrow
Growth rate is moderately rapid and mature within five days and colonies
are velvety to powdery in texture;
surface colony color is white initially becoming light brown or buff tan
in maturation while reverse is tan with brownish center; and
species may even form dark – colored colonies.
Septate hyaline hyphae, conidiophores, annellides, conidia, and
chlamydospores (occasionally), are present;
Conidiophores are dark, may be simple or branched, hyphae – like, and with
Annellides may be solitary, appear in clusters, or may form a penicillus
which are cylindrical and slightly swollen; and
Conidia are hyaline or dark gray in color, unicellular, globose to
pyriform with truncate bases, smooth or rough – walled, and appear in basipetal chains.
precautions are required, no special safety measures needed.
Limited data are
available on the susceptibility activity of Scopulariopsis
species. MICs of fluconazole, itraconazole, and the novel azole Syn -
2869 are high, showing that some azoles have no or very limited in
vitro activity against isolated of Scopulariopsis. Flucytosine
MICs are also high, while amphotericin B, ketoconazole and voriconazole
MICs are variable. Terbinafine with azoles appears synergistic against
Scopulariopsis brevicaulis isolates. For the determination of the
entire extent of in vitro activity of various antifungal compounds
against isolates of Scopulariopsis of various species large – scale
studies are required.