Performance of PCR/Electrospray Ionization-Mass Spectrometry on Whole Blood for Detection of Bloodstream Microorganisms in Patients with Suspected Sepsis.

Blood culture (BC) often fails to detect bloodstream microorganisms in sepsis. However, molecular diagnostics hold great potential. The molecular method PCR/electrospray ionization-mass spectrometry (PCR/ESI-MS) can detect DNA from hundreds of different microorganisms in whole blood. The aim of the present study was to evaluate the performance of this method in a multicenter study including 16 teaching hospitals in the United States (n = 13) and Europe (n = 3). First, on testing of 2,754 contrived whole blood samples, with or without spiked microorganisms, PCR/ESI-MS produced 99.1% true-positive and 97.2% true-negative results. Second, among 1,460 patients with suspected sepsis (sepsis-2 definition), BC and PCR/ESI-MS on whole blood were positive in 14.6% and 25.6% of cases, respectively, with the following result combinations: BC positive and PCR/ESI-MS negative, 4.3%; BC positive and PCR/ESI-MS positive, 10.3%; BC negative and PCR/ESI-MS positive, 15.3%; and BC negative and PCR/ESI-MS negative, 70.1%. Compared with BC, PCR/ESI-MS showed the following sensitivities (coagulase-negative staphylococci not included): Gram-positive bacteria, 58%; Gram-negative bacteria, 78%; and Candida species, 83%. The specificities were >94% for all individual species. Patients who had received prior antimicrobial medications (n = 603) had significantly higher PCR/ESI-MS positivity rates than patients without prior antimicrobial treatment-31% versus 22% (P < 0.0001)-with pronounced differences for Gram-negative bacteria and Candida species. In conclusion, PCR/ESI-MS showed excellent performance on contrived samples. On clinical samples, it showed high specificities, moderately high sensitivities for Gram-negative bacteria and Candida species, and elevated positivity rates during antimicrobial treatment. These promising results encourage further development of molecular diagnostics to be used with whole blood for detection of bloodstream microorganisms in sepsis.

Keratolysis Associated with Methamphetamine Use - Incidental Diagnosis of Corneal Melt in a Patient with Acute Methamphetamine Intoxication.

CASE PRESENTATION: A 38-year-old male presented to the emergency department with methamphetamine-induced agitation. Physical exam showed clouding of the left cornea, with gelatinous appearance and associated conjunctivitis, consistent with corneal melt, or keratolysis. DISCUSSION: Keratolysis is dissolution of the corneal stroma that can lead to corneal ulceration and vision loss. Smoking stimulants has been shown to be associated with this pattern of ocular injury, although this is a relatively rare presentation. Acute keratolysis is a unique complication of methamphetamine preparation and ingestion via smoking that can lead to corneal ulceration and loss of vision.

Paraspinal Abscess in a Two-year-old Female.

A paraspinal abscess is an uncommon condition frequently diagnosed late due to equivocal symptoms, which can lead to increased morbidity and mortality. Commonly associated risk factors include prior invasive spinal procedures, diabetes mellitus, trauma, chronic steroid use, malnutrition, intravenous drug use and an immunocompromised state. Pediatric paraspinal abscesses are not well documented in the literature. We report a case of a two-year-old female presenting with fevers, lower back pain, and decreased oral intake ultimately diagnosed with isolated lumbar paraspinal abscess. The patient underwent an ultrasound-guided percutaneous drainage of the abscess, subsequently improving, and was discharged within 48 hours of presentation.