1. Evaluation of the Film Array Respiratory Panel for Detection of Mycoplasma pneumoniae
and Respiratory Viruses in Multiple Specimen Types
Evaluation of the Film Array Respiratory Panel for Detection of Mycoplasma pneumoniae
and Respiratory Viruses in Multiple Specimen Types
Title Here
Christine Robinson1, Kristin Pretty1, Daniel Olson2, and Samuel Dominguez2
Departments of Pathology and Laboratory Medicine1 and Pediatrics2 , Children’s Hospital Colorado1,2 and University of Colorado2,
Anschutz Medical Campus, CO
Christine Robinson1, Kristin Pretty1, Daniel Olson2, and Samuel Dominguez2
Departments of Pathology and Laboratory Medicine1 and Pediatrics2 , Children’s Hospital Colorado1,2 and University of Colorado2,
Anschutz Medical Campus, CO
BACKGROUND
RESULTS
RESULTS
FILM ARRAY RESP. PANEL - TESTING OF MULTIPLE SPECIMEN TYPES FOR VIRUS
FILM ARRAY RESP. PANEL - TESTING OF MULTIPLE SPECIMEN TYPES FOR MP
ORGANISM AND SIGNIFCANCE
Mycoplasma pneumoniae (Mp) is a bacterial cause of community-acquired pneumonia and occasional extra-pulmonary disease in school-age children and young adults. Most cases are mild but some are hospitalized. Stevens Johnson Syndrome (SJS), a rare but serious disorder involving skin and mucous membranes usually triggered by medication, can also be induced by Mp. Circulation usually is endemic, but outbreaks can occur. Throat swabs (TS) are the usual specimen sent to detect Mp by PCR.
A. Many Specimen Types Testable
B. Validation of FA-RP vs. Luminex RVP
A. Mp Detected in Many Specimen Types
B. Validation of FA-RP Mp PCR vs. Other PCRs
20 NPS
45 NPW
40 TA
40 BAL
Luminex RVP*
Luminex RVP**
Pos
Neg
Total
Film Array RP 24 1 25 28 6 34 20
454
455
640
641
580
480 29
646
675
600
Discrepancy
Missed 1 AdV Detected 1 add'l RV
FA missed 1 AdV
None
Sensitivity
96%
98.70%
100%
Specificity
99.80%
99.10%
Agreement
99.50%
98.90%
Film Array RP
Specimen Types
Mp Pos
Tested
Pos Rate
FDA Cleared
NPS 9
741
1.2%
Lab-Validated NW 64
3421
1.9%
BAL 10
441
2.3% TA 2
222
0.1%
Other
104
0.0%
Total
76 *
4188
1.8%
Total Tested
85 *
4929
1.7%
* 89% of Mp FA positives were in lab-validated specimens
Confirmatory Mp PCR ( CDC and/or Focus)
Same Specimen as FA
Different Specimen as FA
Pos
Neg
Total
Film Array RP 79 4 83 16 2 18
118 85
122
201 87
103
Sensitivity
100%
100.00%
Specificity
96.70%
97.70%
Agreement
98.00%
98%
M. pneumoniae
Scanning electron micrograph.
Hospitalized child with severe SJS skin and eye involvement
* IVD version **RUO version
OUTBREAK
An outbreak of Mp-associated respiratory disease and unusual cluster of Mp- associated SJS was identified in Denver-area children in late 2013, prompting an on-site investigation by CDC. Most of these infections were detected by the Film Array Respiratory Panel (FA RP, Biofire Diagnostics), an FDA-cleared PCR for 17 respiratory viruses and 3 bacteria in nasopharyngeal swabs (NPS). Specimens other than NPS were Mp-positive, although we had not yet validated reporting of bacteria from this test. Other cases were detected by Mp PCR of TS at Focus Diagnostics Laboratory.
MYCOPLASMA PNEUMONIAE
Film Array RP Detects Outbreak
Use of FA for respiratory virus detection begins in early 2013; bacteria to be validated later. If Mp detected, specimen sent to Focus for confirmation before reporting. Mp detection increases significantly in autumn.
C. Agreement between CDC and Focus Mp PCRs
88% agreement when the same 50 FA-positive specimens tested by both laboratories
83% positive agreement when different FA-positive specimens from the same patient tested
CDC PCR identified 4 Mp-positive specimens resulted as Mp negative at Focus; Focus detected no additional positives .
Organisms in FA Respiratory Panel
Viruses Bacteria
Influenza A, H1, H1 2009, H3 Mycoplasma pneumoniae
Influenza B Chlamydophila pneumoniae
RSV Bordetella pertussis
Human metapneumovirus
Adenovirus
Parainfluenza 1-4
Coronaviruses 229E, OC43, HKU1, NL63
Rhinovirus/enterovirus
All FA Results; Feb 2013-Feb 2014
Film Array System
OBJECTIVES
Describe a clinical validation of FA for detection of respiratory viruses and Mp in multiple specimen types including NPS, nasopharyngeal washes (NPW), tracheal aspirates (TA), and bronchoalveolar lavage (BAL), using specimens collected during a Mp outbreak.
Association of MP with SJS
Link between SJS and Mp observed. CDC investigates on-site; verifies community-wide Mp outbreak and association of Mp with some SJS cases.
CONCLUSIONS
METHODS
RESPIRATORY VIRUS VALIDATION: Banked or fresh NPW, TA, and BAL positive by Luminex Respiratory Virus Panel (LUM, IUO version), donated LUM-positive NPS, and negative specimens spiked with virus were combined into 2-specimen pools and tested by FA v1.6. The number of expected and observed analytes for each pool was scored.
Mp – CLINICAL VALIDATION: 288 banked or fresh respiratory specimens positive or negative for Mp by FA were sent to the CDC’s Mycoplasma Laboratory only (19 pos), Focus Reference Laboratory (16 pos, 203 neg), or both laboratories (50 pos) for Mp PCR. Mp strain typing by MLVA and resistance testing was performed at CDC.
Mp – ANALYTICAL VALIDATION: In progress
Specimens other than NPS can be tested for viruses by Film Array RP and resulted with confidence
Detection of bacteria compared to viruses in respiratory tract specimens of children is low
An outbreak of Mp tract disease identified by Mp PCR of respiratory tract specimens occurred in late 2013 in Denver area children. Some cases were associated with Stevens-Johnson Disease
Clinical detection of M. pneumoniae by Film Array RP was validated in multiple specimen types
7 Mp-associated probable SJS cases identified Aug-Nov 2013; 5 considered confirmed. All had severe disease; several had recurrent disease.
3 different strains of Mp were circulating; no single strain was identified in SJS patients
All 4 Mp from SJS patients were macrolide sensitive; 7% of 45 Mp from non-SJS patients and contacts were resistant.