Legionella(L) Risk Associated with Ice Machines (IM) in Hospitalized Patients at University of Pittsburgh Medical Center Presbyterian (UPMC-P)
Background: L is common in many environments (soil , water (W), etc.) but only multiplies at 20°C-50°C. Therefore, L preventative measures such as Copper (C)/Silver (S) ionization are directed at warm W systems and have been in place at UPMC-P since 1984. Ion levels are monitored monthly with prescribed protocols for low levels and/or + faucets. In 10/13 a transplant patient developed respiratory failure thought to have recurrent hospital acquired pneumonia (HAP). Despite therapy the patient died. A bronchoalveolar lavage grew L. pneumophilia (P) not sero 1. The objective of this study was to investigate a L HAP.
Methods: All hot W sources in patient's care area (7 faucets and 4 showers – all negative) were cultured. Adequate C/S levels were confirmed and L surveillance increased. The patient had been ordered NPO with ice and had a witnessed aspiration. The IM cultured + for LP NOT serogroup 1 and a fluorescent L species. Over the next month 2 immunocompetent cases were identified. They were no identified commonalities except NPO with ice orders and witnessed aspiration. W sources and ice from patients' care areas were culture negative. Ice from 16 IMs (4 of which had W reservoir (R)) and 10 additional WRs were cultured All IMs were sanitized using CDC defined methods and in-line 0.2µ W Filters were placed to prevent entry of L. Overall 47 clinical care IMs and 15 WRs were cultured for L.
1/6 IM was replaced, sanitized, filtered, and weekly cultured negative X 4. 5/6 + IMs were sanitized/filtered. 1/5 was repetitively + and required disassembly to identify issues unique to that IM. Issues identified that facilitated growth/resistance to disinfection.
· Thermal element (generator) adjacent to the WR generated temps as high as 94.80 F.
· Maintenance process was directed at descaling, not disinfecting
· Some IM components remained + due to lack of contact with the disinfectant
· L amplification can occur in IM WR at increased temperatures due to proximity of the generator.
· IMs should be routinely chlorinated and descaled.
· Small pore filters may prevent introduction of L into IM.
· Routine sanitizing, filtering, and culturing of patient care IMs is likely necessary to prevent L colonization/infections in susceptible hospitalized patients.
E. Dudek, None
A. Galdys, None
L. Rack, None
L. Young, None
J. Crouse, None
A. Pasculle, None