A clinicoepidemiologic study was undertaken to investigate an apparent increase in frequency of nosocomial invasive filamentous fungal disease (NIFFD) in adult patients with acute leukemia hospitalized during a period of hospital construction, and to determine if a relationship existed between the construction activity and the acquisition of NIFFD.
The first study goal, to determine the incidence of NIFFD before and during construction, was approached by calculation of incidence rates of NIFFD in patients with acute leukemia, comparing 1982 and 1983 (a baseline period free of construction) to 1986 (a year when construction activity was at its peak). The second study goal, to identify risk factors for the development of NIFFD, was accomplished by reviewing the autopsy records of all patients with underlying hematologic disorders accompanied by granulocytopenia who died in our hospital from 1982 through 1986. Patients with and without autopsy evidence of NIFFD were then compared by univariate and multivariate (logistic regression) analysis to identify potential risk factors for the acquisition of NIFFD.
The incidence of NIFFD in patients with acute leukemia hospitalized during the period of hospital construction was significantly increased when compared to a baseline period without construction (11 per 139 versus 4 per 333, p < .001). Review of all granulocytopenic patients autopsied over the five-year interval 1982 through 1986 revealed duration of granulocytopenia and hospitalization during construction to be risk factors for NIFFD by univariate analysis (p < .005). Logistic regression showed duration of granulocytopenia to be a highly significant independent risk factor (p < .01) and construction activity to be a probable independent risk factor (p = .09). The effect of construction on risk of NIFFD was most striking in those patients granulocytopenic for less than 40 days. The increased incidence of NIFFD occurred despite anticipation of this potential problem and compliance with published recommendations for infection control during periods of hospital construction.
Given the potentiating effect of construction activity on the occurrence of NIFFD in granulocytopenic patients and the suboptimal impact of standard recommended preventive measures, additional risk-reduction methods (i.e., surveillance culturing, prophylactic antifungal therapy, use of portable high efficiency particulate air filters) may be appropriate for patients expected to experience prolonged granulocytopenia (> 14 days) while hospitalized during periods of major construction activity involving excavation. Further studies will be necessary to define the roles of each of these modalities.