Sunday 16 November 2008

Bipolaris specefara:

Fungus

Bipolaris is a dematiaceous filamentous fungus. It is cosmopolitan in nature and is isolated from plant debris and soil. Bipolaris can infect both immunocompetent and immunocompromised host. Bipolaris is one of the causative agents of phaeohyphomycosis. The clinical spectrum is diverse, including allergic and chronic invasive sinusitis, keratitis, endophthalmitis, endocarditis, endarteritis, osteomyelitis, meningoencephalitis, peritonitis, otitis media (in agricultural field workers) and fungemia as well as cutaneous and pulmonary infections and allergic bronchopulmonary disease. Bipolaris can infect both immunocompetent and immunocompromised host.

The hyphae are septate and brown. Conidiophores (4.5-6 µm wide) are brown, simple or branched, bending at the points where each conidium arises from. The conidia, which are also called poroconidia, are 3- to 6-celled, fusoid to cylindrical in shape and are light to dark brown in color.

Amphotericin B and ketoconazole are used in treatment of Bipolaris infections. Surgical debridement may be indicated in some cases, such as sinusitis

The photomicrograph above has the indicator pointed at one of the typical poroconidia which is attached to it‘s conidophore from where it has branched off the hyphae. It is of a wet preparation stained with Lactophenol Cotton Blue and viewed under x800.