In patients with intravascular catheters who are febrile or have positive blood cultures and no other obvious sources of infection, catheter tip cultures are often obtained to evaluate potential catheter-related bloodstream infections. However, previous studies reported that the management of catheter-related bloodstream infection cases is entirely based on blood culture growth and susceptibilities and that catheter tip cultures have low diagnostic positive predictive value.

Blood cultures (BC) for bacteria and yeast have traditionally been incubated for 5 days using modern instruments. Many organisms may grow sooner, and the need for the full 5-day incubation period has been questioned.

Background This study evaluated the yield of testing NP vs BAL specimens using a multiplex PCR respiratory viral panel (RVP). Methods A retrospective chart review was conducted on all patients from 10/2017-3/2021 who had both an NP swab and BAL tested by RVP within a 4-week period. Results There were 477 cases where patients had both an NP and BAL specimen tested by RVP. Results were NP-/BAL- for 361 (76%) cases, NP+/BAL+ for 58 (12%), NP-/BAL+ for 40 (8%), and NP+/BAL- for 18 (4%). For NP+/BAL+, NP-/BAL+, and NP+/BAL-, respectively, rhinovirus was detected in 23 (40%), 3 (8%), and 16 (89%) cases (p< 0.001); influenza A or B in 9 (16%), 7 (18%), and 0 (0%) (ns); adenovirus in 3 (5%), 10 (25%), and 2 (11%) (p< 0.05); metapneumovirus in 9 (16%), 8 (20%), 2 (11%) (ns); RSV in 8 (14%), 6 (15%), and 1 (6%) (ns); and, parainfluenza in 7 (12%), 6 (15%), and 1 (6%) (ns), respectively. Average ages were 48, 48, and 48 years; numbers of males were 34 (58%), 28 (70%), and 11 (61%); immunocompromised were 56 (97%), 37 (92%), and 17 (94%); and, 16 (28%), 10 (25%), and 6 (33%) had an active malignancy, respectively (all ns). Average symptom durations prior to presentation were 7.0, 13.1, and 9.6 days (ns); pulmonary exams were abnormal in 35 (60%), 24 (60%), and 5 (28%) cases (p< 0.05); shortness of breath (SOB) was present in 40 (69%), 25 (62%), and 8 (44%) (ns); lower respiratory tract infection (LRTI) symptoms were absent in 1 (2%), 12 (30%), and 8 (45%) cases (p< 0.01); when spirometry values were available, they were reduced in 28/31 (90%), 15/19 (79%), and 3/8 (37%) cases (p< 0.05); and, mean SpO2 levels were 91.5%, 93.9%, and 93.7% (ns), respectively. Mean temperatures were 99.0F, 99.0F, and 99.1F (ns); chills, sweats, and malaise were present in 27 (47%), 13 (33%), and 3 (17%) cases (p< 0.05); GI symptoms were present in 20 (34%), 5 (13%), and 10 (56%) cases (p< 0.05); and, acute kidney injury was present in 38 (66%), 13 (33%), and 6 (33%) cases (p< 0.05), respectively. Conclusion Most (88%) RVP test results were concordant between NP and BAL. There were significant differences between cases of NP+/BAL+, NP-/BAL+, and NP+/BAL-. Rhinovirus and GI symptoms were more common for NP+/BAL- vs NP-/BAL+. Conversely, pulmonary exams were more often abnormal and spirometry values reduced for NP-/BAL+ vs NP+/BAL-. Disclosures All Authors: No reported disclosures