A 25 years old female complains of recurrent rhinitis, nasal discharge and bilateral nasal blockage since one year. She has history of asthma and allergy. On examination multiple ethmoidal polyps are noted with mucosal thickening and impacted secretions in both the nasal cavities. Biopsy is taken and the material is cultured which shown the growth of many hyphae and pseudo hyphae with dichotomous branching typically at 45deg. Which of the following is the most likely responsible organism?

Ans. is 'a' i.e., Aspergillus fumigatus(Ref: Harrison, 18th/e, p. 1655, 1656 and 17th/e, p. 1257)* Information provided in this question are:(i) Recurrent rhinitis, nasal discharge, bilateral nasal blockade.(ii) History of asthma and allergy.(iii) Hyphae with dichotomous branching at 45degC.* All suggest the diagnosis of Aspergillus fumigatus.(i) Most common type of fungal infection of nose and paranasal sinuses are due to Aspergillus.(ii) Most common fungus causing allergy is aspergillus.(iii) Aspergillus has septate hyphae that branch typically at 45degC (V shaped).