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Case Reports
. 2018 Jan-Mar;8(1):61-63.
doi: 10.4103/ijabmr.IJABMR_459_16.

Atypical Pneumococcal Isolate from Blood

Jayashree Veerasamy  1 , Jayalakshmi Jayarajan  2
Affiliations
Case Reports

Atypical Pneumococcal Isolate from Blood

Jayashree Veerasamy et al. Int J Appl Basic Med Res. 2018 Jan-Mar.

Abstract

Pneumonia with bacteremia accounts for the majority (70%) of cases of invasive pneumococcal diseases. Laboratory characterization of pneumococci is routinely done by sensitivity to optochin. We identified an atypical presentation of optochin-resistant pneumococci in blood isolate of a patient with sepsis. Polymerase chain reaction for autolysin (lytA) and pneumolysin (ply) was positive in the bile soluble isolate. Gene sequencing revealed synonymous single nucleotide polymorphism type of functional mutation in lytA gene. There have been emerging reports of optochin-resistant pneumococci. Diminishing relevance and reliability of optochin sensitivity testing in identifying pneumococci in clinical samples has been highlighted by this case report.

Keywords: Atypical; bacteremia; optochin resistance; pneumococci.

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Conflict of interest statement

There are no conflicts of interest.

Figures

Figure 1
Figure 1
Lane 1 – DNA ladder, lane 2 – lytA (319 bp) and lane 7 – ply gene (348 bp) for optochin-resistant bile soluble blood isolate
Figure 2
Figure 2
Gene sequencing for lyt A (forward primer)
Figure 3
Figure 3
Gene sequencing for lyt A (reverse primer)
See this image and copyright information in PMC

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