# Presentation: 753050

## Bacterial Contamination of PlateletsExperience atUniversity Hospitals of Cleveland,1991-2005

- Michael R. Jacobs, MD, PhD
- Roslyn Yomtovian, MD
- Case Western Reserve University and University Hospitals of Cleveland, Cleveland, Ohio

## Disclosures

- Drs Yomtovian and Jacobs have received funding as investigators at Case Western Reserve University and University Hospitals of Cleveland to investigate bacterial contamination of platelets from Gambro, Hemosystem, Immunetics, Pall Corporation, and Verax
- Travel expenses for our attendance at this meeting are being paid by University Hospitals of Cleveland
- Dr Yomtovian is an advisor to Verax and Immunetics

## Bacterial Contamination of Platelet Pools Ohio, 1991

- From June 27 through July 30, 1991, four episodes of bacterial contamination of platelet pools occurred in an Ohio hospital and were reported by the hospital through the Food and Drug  Administration (FDA)  to CDC. This report summarizes the results of the epidemiologic investigation of these episodes.
- http://www.cdc.gov/mmwr/preview/mmwrhtml/images/ic_wk.gif
- January 24, 1992 / 41(03);36-37 (Zaza, Tokars, Yomtovian et al. Infect Cont Hosp Epidemiol 1994;15:82-87).

## Case Definition and Methods

- Isolation of an organism from an aliquot of a platelet product obtained at time of issue by plate culture of 0.1 ml on a blood agar plate incubated in 5% CO2 for up to 48 h
- 		PLUS
- Repeat isolation of the same organism from the same source (aliquot and/or nearly empty unit retained at 4oC), and, in the case of RDP pools, from the remnants of one of the RDPs (retained at 4oC) used to make up the pool
- Quantitative plate cultures of serial 1-in-10 dilutions of all products with initial bacterial growth were performed

## Bacterial species 1991-2005, N=46

**Data from:**
**	****CDC. 1992. Morb Mortal Wkly Rep 41:36-37.****	****Yomtovian, R, et al.. Transfusion 2006, in press.**
**	****Zaza S, et al. Infect Control Hosp Epidemiol 1994;15(2):82-7.   ****	****Yomtovian, R, Jacobs, M. 2006. Unpublished data**
**	****Sapatnekar S, et al.. Transfusion 2001;41(11):1426-30.**

**Active **
**surveillance**

## Bacterial contamination of platelets – Cleveland 1991-2005, N=46

- RDP units	35
- SDP units:	11
- Age at issue:
- 2-3 d	  6
- 4-5 d	40
- Detected by active surveillance	43
- Detected by passive surveillance	  3

## Number of instances and rates of bacterial contamination detected by active surveillance, and number of cases and rates of transfusion reactions and bacteremia for platelet transfusions by transfusion episode and by platelet unit for all platelet transfusions

|  | SDP units | RDP – per unit |  | RDP - per pool |  | All transfusionsc |
| --- | --- | --- | --- | --- | --- | --- |
|  | No. of cases (rate) | No. of cases (rate) | P valuea | No. of cases (rate) | P valueb | No. of cases (rate) |
| Bacterial contaminationd | 7/15,493
(1:2,213) | 31/64,805
(1:2,090) | 0.89 | 31/12,961
(1:418) | <0.001 | 38/28,454
(1:749) |
| Contaminated units transfusede | 6/48,067
(1:8,011) | 26/168,216
(1:6,470) | 0.68 | 26/33,637
(1:1,294) | <0.001 | 32/81,704
(1:2,556) |
| Transfusion reactione | 3/48,067
(1:16,022) | 10/168,216
(1:16,822) | 0.75 | 10/33,637
(1:3,364) | 0.01 | 13/81,704
(1:6,285) |
| Bacteremiae | 1/48,067
(1:48,067) | 6/168,216
(1:28,036) | 0.66 | 6/33,637
(1:5,606) | 0.02 | 7/81,704
(1:11,672) |

- a P value by Fisher exact method for RDP units compared to SDP units	b P value by Fisher exact method for RDP pools compared to SDP units
- c_ _Based on total of SDP unit and RDP pool transfusions	d Numerators used for these calculations are the number of cases detected by active surveillance, while denominators are the numbers of platelet units and/or pools cultured during active surveillance
- e Numerators used for these calculations are the number of cases detected by active and passive surveillance, while denominators are the number of platelet units and/or pools transfused.  Note that 7 of the 38 contaminated units identified by active surveillance were not transfused, while the contaminated unit detected by passive surveillance is included in these calculations, resulting in transfusion of 32 contaminated units.

**R. Yomtovian, E. Palavecino, A. Dysktra, K. A. Downes, A. Morrissey, S. Bajaksouzian, M. Pokorny, H. M. Lazarus , M.R. Jacobs. Evolution of Surveillance Methods for Detection of Bacterial Contamination of Platelets in a University Hospital, 1991-2004.  Transfusion 2006, in press.**

## Detection by Gram stain, N=39

**R. Yomtovian, E. Palavecino, A. Dysktra, K. A. Downes, A. Morrissey, S. Bajaksouzian, M. Pokorny, H. M. Lazarus , M.R. Jacobs. Evolution of Surveillance Methods for Detection of Bacterial Contamination of Platelets in a University Hospital, 1991-2004.  Transfusion 2006, in press.**

- Platelet products were interdicted before use by detection of a positive Gram stain in 6 instances:
- 8 X 106 to 4 X 1011 cfu/ml of coagulase-negative staphylococci were isolated from these products

## Bacterial species and load vs. transfusion reaction 1991-2004, N=32*

- Bacterial count (cfu/ml)

- *R. Yomtovian, E. Palavecino, A. Dysktra, K. A. Downes, A. Morrissey, S. Bajaksouzian, M. Pokorny, H. M. Lazarus , M.R. Jacobs. **Evolution of Surveillance Methods for Detection of Bacterial Contamination of Platelets in a University Hospital, 1991-2004.  Transfusion 2006, in press.**

## Bacterial species and load vs. transfusion reaction 1991-2005, N=38

## Bacterial species and load vs. transfusion reaction 1991-2005, N=38

- A system with a sensitivity of 105 cfu/ml would detect 10/11 (91%) serious reactions and 15/19 (79%) of all reactions

## Bacterial species and load vs. transfusion reaction 1991-2005, N=38

- A system with a sensitivity of 104 cfu/ml would detect all 11  serious reactions and 16/19 (84%) of all reactions

## Bacterial species and load vs. transfusion reaction 1991-2005, N=38

- A system with a sensitivity of 103 cfu/ml would detect all 11  serious reactions, 18/19 (95%) of all reactions, and 30/38 (79%) of all cases

## Cases from units screened at 24 h

- Three of our recent cases (“breakthroughs”) were in apheresis units screened for bacterial contamination at 24 h:

| Screening method | Age issued (days) | Culture at issue | Quantitation (CFU/mL) |
| --- | --- | --- | --- |
| Plate culture | 4 | Serratia marcescens | 8.5 X 107 |
| eBDS | 3 | Staphylococcus aureus | 2.3 X 103 |
| BACT/Alert | 5 | Coagulase-negative staphylococcus | 1.3 X 107 |

## Validation studies of at issue detection methods

- These studies are time-consuming and much more difficult to perform than studies of early culture methods
- Inoculating platelets with low numbers of bacteria is difficult to achieve technically – 10-50 CFU/mL is the lowest range that is technically reproducible
- It is difficult to work with some species at low inocula as units often self-sterilize (e.g., *Pseudomonas aeruginosa*, coagulase-negative staphylococci)
- Validation studies should concentrate on the most virulent pathogens -*Enterobacteriaceae*, *Pseudomonas aeruginosa*, *Staphylococcus aureus*, *Bacillus cereus*, *Streptococcus bovis*, and single most common contaminant, coagulase negative staphylococci
- Species that have only been reported once (e.g., *Clostridium perfringens*), have never been reported (e.g., *Clostridium difficile*), or are very rare and of very low virulence (e.g., *Proprionebacterium acnes*) do not need, in our opinion, to be studied

## Conclusions

- Bacterial contamination of platelets is a significant problem
- Contamination rate of older RPD and SDP units is around 1:2,000 units, with rate being 5-fold higher in RDP pools
- Rate of transfusion reactions associated with bacterial contamination, based on all transfusions, is at least 1:16,000 RPD and SDP units, with rate being 5-fold higher in RDP pools
- Since introduction of new rules for limiting contamination in March 2004, 3/10 instances were “breakthrough” cases in apheresis units screened at 24-h (*Serratia marcescens* 8.5 x 107 CFU/mL, *Staph. aureus* 1.0 x 103 CFU/mL; CONS 1.3 x 107 CFU/mL)
- Based on our experience over 15 years, an at issue detection system with a sensitivity of :
- 105 CFU/ml would have detected 10/11 serious reactions, and 15/19 (79%) with any reaction
- 104 CFU/ml would have detected all 11 serious reactions, and 16/19 (84%) with any reaction
- 103 CFU/ml would have detected 30/38 (79%) cases, including all serious reactions and 18/19 (95%) reactions of any kind

## The bottom line .....

- An at issue detection system with
-    a sensitivity of:
- 105 CFU/ml would have prevented all fatal reactions, 91% of serious reactions, and 79% of all reactions
- 103 CFU/ml would have prevented all serious reactions, 79% of all cases and 95% of all reactions

## Thank you