1. What is the causative agent, how does it enter the body and
how does it spread a) within the body and b) from person to
Aspergillosis is caused by
a saprophytic, filamentous fungus
found in soil, decaying vegetation, hay, stored grain, compost piles,
mulches, sewage facilities, and bird excreta. It is also found in water stor-
age tanks (for example in hospitals), fire-proofing materials, bedding, pil-
lows, ventilation and air conditioning, and computer fans. It is a frequent
contaminant of laboratory media and clinical specimens, and can even
grow in disinfectants!
is not the most abundant fungus in the world, it is one
of the most ubiquitous. There are more than 100 species of
Although about 10 000 genes have been identified in the
genome, none of the gene sets is shared with other fungal pathogens.
The cell wall of
contains various polysaccharides (Figure 2).
(1-3)-glucans are modified and associated to the other
cell wall polysaccharides (chitin, galactomannan, and
A 68-year-old Caucasian man was diagnosed with B-cell
(B-CLL) and received
various regimens of chemotherapy. As a patient with
chronic leukemia he attended the CLL clinic regularly. Ten
years later the patient presented with
symptoms and was examined by chest
results were suggestive of aspergillosis and additional
laboratory tests were done. Positive
allowed the doctors in the clinic to give a diagnosis of
pneumonia. The patient was not neutropenic
and his condition improved following an 8-month course
of itraconazole followed by voriconazole for 6 months.
Two years later the patient was diagnosed with
pulmonary aspergillosis. The diagnosis was based on a CT
scan, cytology results, and a history of prior infection
(Figure 1). He was treated with amphotericin B, monitored
by radiography, followed by caspofungin for 9 days, but he
died 2 days later of drug discontinuation. An autopsy was
performed and the diagnosis of invasive pulmonary
aspergillosis was confirmed.
Chest X-ray showing that the fungus has
invaded the lung tissue.
There is a large cavity in the upper
left lobe of the lung, with a fungus ball within the cavity.
© Lydyard, Peter; Cole, Michael; Holton, John; Irving, Will; Porakishvili, Nino; Venkatesan, Pradhib; Ward, Kate, Jan 01, 201
Garland Science, Hoboken, ISBN: 9780203856871