922. Impact of a multiplex PCR-based testing system on the management of severe nosocomial pneumonia
Session: Poster Abstract Session: Respiratory Infections
Friday, October 4, 2013
Room: The Moscone Center: Poster Hall C

With the current paradigm for treatment of pneumonia, results of conventional microbiology culture of respiratory samples are not available for at least 48-72 h. However, empiric treatment must commence immediately without the benefit of knowing the potential causative pathogen. Conceivably, robust rapid molecular diagnostic technique in the routine laboratory might prevent some inappropriate and inadequate therapies. Our objective was to investigate the impact of multiplex PCR assay, on the management of severe nosocomial pneumonia.


Fifteen patients with severe pneumonia were recruited into the study. Their bio-data and clinical parameters were carefully recorded. Respiratory samples were collected and processed with multiplexed PCR-based Pneumonia Assay System. The same samples were processed by conventional methods, including Gram stain and culture. Other conventional tests included blood culture, blood gases, hematological and biochemical profiles. Empiric antimicrobial therapy was started immediately according to treatment policy and modified as necessary.


Twelve of the 15 patients were evaluable; 3 were excluded on basis of negative results with PCR and positivity for Mycobacterium tuberculosis. Their ages ranged from 35-79 years (mean=60.6 years). All had leukocytosis, elevated C-reactive protein and increased oxygen requirement.  The Assay identified multi-drug resistant (MDR) single and multiple pathogens, with good correlation between phenotype and genotype for third-generation cephalosporins, carbapenem, macrolide and gyrase inhibitor resistance, from the respiratory samples of patients within c.4.5 h compared with 48-72 h for conventional results. Antibiotic treatment was adjusted to appropriate therapy based on assay results in all patients; 10 (83.3%) improved and 2/12 died mainly of co-morbidities. Eight (66.7%) would have been inappropriately treated if based on results of conventional testing.


PCR-based  Assay dramatically shortened the sample-to-answer timeframe from 72 to 4.5h and helped to provide accurate treatment in all patients. This assay holds promise in improving the standard of care for patients with pneumonia.

Vincent Rotimi, MD, PhD1, Ebtehal Al Roomi, MD2, Lubna Abdulaziz, BSc3 and Wafaa Jamal, MD, PhD1, (1)Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait, (2)Mubarak Al Kabeer Hospital, Hawally, Kuwait, (3)Microbiology, Mubarak Al Kaber Hospital, Jabriya, Kuwait


V. Rotimi, None

E. Al Roomi, None

L. Abdulaziz, None

W. Jamal, None

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