Quality in Diagnostic Microbiology: Experiential Note to Emphasize Value of Internal Control Programs
QC 1/2009 was taken from the sputum culture of a 10-year-old girl with cystic fibrosis. In addition to this isolate there was also Stenotrophomonas maltophilia and Aspergillus fumigatus. This organism did not readily identify. Because it was not a ‘classical’ Pseudomonas aeruginosa, we set up a Vitek GNI + card. The result was Pseudomonas aeruginosa 87%. Although with other characteristics, it appeared to be a mucoid Pseudomonas aeruginosa, a 20NE was set up. The 20NE gave a result of Burkholderia cepacia 99%. However, this isolate would not produce the typical colonies on Burkholderia agar. Three days later, we received another sputum specimen on the same patient. The second specimen on this patient also yielded the same mucoid organism. This time, the Vitek ID was Pseudomonas aeruginosa 99%. Although it appears that the Shewanella and Burkholderia results produced by other laboratories came from wrong API results, it was pleasing to note complete agreement on antibiotic susceptibility testing on this isolate. Based on the date of dispatch being Monday, February 16 and the receipt of reports being between February 19 and March 2, it was also noted that the turnaround times for this particular QC ranged from 2 to 13 days.