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ASPERGILLUS FUMIGATUS 



Cases of pseudo-tuberculosis due to an Aspergillus have also been recorded 

 by several observers as occurring in the human subject. Aspergillus fumigatus 

 has been found in infections of the ear and naso-pharynx, and in cases of 

 keratitis with hypopyon following wounds of the eye caused by vegetable 

 tissues. 



Pigeon-crammers are very subject to aspergillary pseudo- tuberculosis. In pigeons 

 there is often a " chancre " on the buccal mucous membrane due to an Aspergillus. 

 The disease is also found in hair- combers who use flour of rye which is often infected 

 with spores of Aspergillus for removing the grease from hair. In human aspergil- 

 lary pseudo-tuberculosis the fungus is often associated with the tubercle bacillus. 

 A. fumigatus has also been found in the lesions of pneumo- mycosis in the horse and 

 cow. Renon has found that by sowing millet seeds, vetch, oats, maize, wheat, and 

 other varieties of corn on appropriate media cultures of various species of Aspergillus 

 can be obtained the commonest being A. fumigatus. 



1. Experimental inoculation. Pigeons, rabbits, guinea-pigs and monkeys, 

 are susceptible to infection with A. fumigatus. Dogs and cats, on the other 

 hand, seem to be immune. 



Pigeons are the best animals for purposes of experimental inoculation. 

 The inoculation of 2-3 c.c. of a culture on Raulin's medium into the axillary 

 vein leads to the death of the pigeon in 2 or 3 days. A dose of 1 c.c. produces 

 a disease which runs a longer course ending in death in about a fortnight. 

 By passage through pigeons the virulence of the parasite can be raised 

 (Kotlair). 



When death occurs soon after inoculation, the naked eye lesions in the 

 pigeon are very scanty : tubercles will be found in the liver, but the lungs 

 and spleen appear simply hypersemic. When the disease is of longer duration, 

 numerous tubercles can be seen with the naked eye in the internal organs : 

 these are especially well marked in the liver and may show all the stages 

 of development of a typical tuberculosis (miliary tubercles, caseous degene- 

 ration and fibrous changes). 



Microscopical examination too shows that the lesions bear a close general 

 resemblance to those of true tuberculosis but in all of 

 them a thick felting of mycelium and spores is visible. 



2. Morphology. Microscopical appearance. Aspergillus 

 fumigatus consists of a filamentous mycelium with hyphae 

 projecting from it at right angles, these latter are swollen 

 into club-shaped masses (spore-bearing hyphse) carrying 

 undivided sterigmata into which chains of conidia are 

 inserted : the conidia are rounded, smooth, of a brown or 

 green colour and readily dehisce ; they measure about 3/u, 

 in diameter. In sputum, a more or less dense felted mass 

 of mycelium is found. 



Staining reactions. Aspergillus fumigatus stains well 

 with the aniline dyes and is gram-positive providing that 

 the staining is prolonged. 



Cultural characteristics. Aspergillus fumigatus grows 

 best in Kaulin's liquid or beer-wort. It is strictly aerobic 

 and grows at all temperatures between 22 and 40 C. 



In broth. Growth is very slow and scanty. Flakes 

 ^ m . vcenum are found floating in the medium which 

 remains clear. It is very uncommon to find spores under 

 these conditions. 



In Raulin s medium. Growth is abundant : numerous flakes are seen 

 after incubating for 15 hours at 37 C. In the culture tangled masses of 

 filaments and very numerous fructifications will be seen on microscopical 



tion. 



