OBJECTIVE: To characterize the epidemiology of invasive pulmonary aspergill
osis (IPA).
DESIGN: A retrospective case series.
SETTING: An 850-bed, academic. tertiary-care medical center.
PARTICIPANTS: Adult inpatients, between January 1, 1990, and December 31, 1
998, with either a histopathology report consistent with IPA or a discharge
diagnosis of aspergillosis.
METHODS: We reviewed medical records and categorized case-patients as defin
itive or probable and acquisition of IPA as nosocomial, indeterminate, or c
ommunity using standard definitions. To determine the rate of aspergillus r
espiratory colonization, we identified all inpatients who had a respiratory
culture positive for Aspergillus species without a histopathology report c
onsistent with IPA or a discharge diagnosis of aspergillosis. Three study i
ntervals were defined: interval 1, 1990 to 1992; interval 2, 1993 to 1995;
and interval 3, 1996 to 1998. Carpeting in rooms for patients following hea
rt-lung and liver transplant was removed and ceiling tiles were replaced du
ring interval 1; a major earthquake occurred during interval 2.
RESULTS: 72 case-patients and 433 patients with respiratory colonization we
re identified. Acquisition was nosocomial for 18 (25.0%), indeterminate for
9 (12.5%), and community-acquired for 45 (62.5%) case-patients. Seventeen
(23.6%) of the 72 case-patients had prior transplants, including 15 solid o
rgan and 2 bone marrow. The IPA rate per 100 solid organ transplants (SOTs)
decreased from 2.45 during interval 1 to 0.93 during interval 2 and to 0.5
2 during interval 3 (chi-square for trend, 5.44; P < .05). The hospitalwide
IPA rate remained stable at 0.03 per 1,000 patient days.
CONCLUSIONS: The SOT IPA rate decreased after intervals 1 and 2, although t
he hospitalwide IPA rate remained stable during the study period. Post-eart
hquake hospital demolition and construction occurring after interval 2 was
not associated with an increase in the rate of IPA at our institution.