An early diabetic has left sided orbital cellulitis CT scan of paranasal sinus shows evidence of left maxillary sinusitis. Gram stained smear of the orbital exudate shows irregularly branching septate hyphae. The following is most likely etiological agent:

Ans. (a) Aspergillus Ref. Ananthanarayan 8/e, p 613, 9/e, p 609; Harrison 19/e, p 1345 - 1347, 18/e, p 1658 "Presence of branched septate hyphae in a patient of orbital cellulitis (occur as complication of sinusitis) suggest Aspergillus." Aspergillus Sinusitis occur in three forms: Ball of hyphae may form in chronically obstructed paranasal sinus, without tissue invasion. A chronic fibrosing granulomatous inflammation begin in sinus and spread slowly to the orbit and brain. Allergic fungal sinusitis Mucor and Rhizopus belong to family Zygomycetes and have non-septate hyphae.