is a cosmopolitan fungus commonly found in humid soils and decaying plant
material. It is also isolated from parasitized insects and amphibians.
The majority of human infection cases come from tropical and subtropical
regions and particularly at Central America, equatorial Africa, and India.
genus Conidiobolus contains a number of species. The most
widespread ones are Conidiobolus coronatus, Conidiobolus
incongruus and Conidiobolus lamprauges.
Pathogenicity and Health Effects
species is a causative agent of subcutaneous infection in humans which
involves the nasal mucosa and maxillofacial tissues. This chronic
inflammatory granulomatous infection is also referred to as
entomophthoromycosis conidiobolae. It involves facial subcutaneous
tissues and paranasal sinuses and is characterized by the formation of
firm, subcutaneous nodules or polyps. The infection may be acquired
through breathing in of airborne mold spores or through a minor trauma
such as an insect bite. The infected host is commonly a healthy
individual working outdoors in tropical areas. However, the infection may
also develop in patients with underlying pathologies such as neutropenia
or Burkitt's lymphoma. Thus, the species is considered as an
opportunistic pathogen as well. Fatal, deeply invasive infections are
encountered very seldom. Health cases involving pulmonary and pericardial
have also been reported.
species are the causative agents of infections in humans, sheep, dogs,
deer, and horses.
Colonies grow very rapid and are initially glabrous and
waxy in texture and become powdery after aerial hyphae development;
Surface colony color is white becoming beige to brown by aging and while
pale on the reverse; and
Satellite colonies are formed due to discharged sporangioles by the
More or less septated
with diameter ranging from 10 - 30 µm,
zygospores, and chlamydoconidia are present;
sporangiophores with size ranging from 18 to 22 x 60 – 90 µm are scarcely
differentiated from vegetative hyphae and are slightly tapered towards the
tip which carry unicellular round primary spores that are forcibly
discharged at maturity;
– spored sporangioles called ballistospores are ejectible, round to
pyriform in shape but with a prominent papilla which is the site of former
attachment to the sporangiophore;
Villose sporangioles are formed in old cultures and have smooth surface
and covered with hair-like appendages;
primary sporangioles may germinate and produce spore – bearing
sporangiophores and some primary sporangioles themselves may also produce
numerous secondary sporangioles which, in turn, form a “corona” around the
primary sporangioles; and
Zygospores are commonly thick – walled, globose to elongate in shape, and
Only general laboratory precautions are required, no special safety
Data on in vitro activity of anti – fungal agents isolated of
Conidiobolus are very limited. Generated considerably high MICs for
limited colonies of Conidiobolus coronatus and Conidiobolus
lamprauges isolates tested are amphotericin B, flucytosine, fluconazole, itraconazole, ketoconazole, and miconazole.
Potassium iodide, trimethoprim-sulfamethoxazole, and azole derivatives
have been used as treatment; however, there is yet no standard regimen for
treatment of Conidiobolus infections.