Studies of the outcome of Pseudomonas aeruginosa bacteremia (Pab) have focused mainly on antibiotic appropriateness. However, P. aeruginosa possesses many virulence factors whose roles in outcomes have not been examined in humans, except for the type III secretion system (T3SS) toxins. The purpose of this study was to examine the role of virulence factors other than the T3SS toxins. Bacterial isolates were collected from 75 patients who suffered from Pa blood stream infections. Host factors such as neutropenia, immunosuppression, comorbidities, time to effective antibiotics, source of bacteremia, and presence of multidrug resistant (MDR) isolate were studied. The isolates were analyzed for the presence of toxin genes, proteolytic activity, swimming and twitching motility, and pyocyanin production. The data were analyzed to ascertain which virulence factors correlated with poor outcomes defined as septic shock or death (SS) within 7 days. Septic shock or death occurred in 25/75 patients. Univariate analysis identified age as a host factor that exerted a significant effect on these outcomes. Ineffective antibiotics administered during the first 24 hours of treatment or MDR P. aeruginosa did not influence the frequency of SS, nor did the presence of lasB, exoA, exoS exoU, plcH genes and proteolytic activity. However, 6/8 patients infected with non-motile isolates, developed SS, p = 0.014 and 5/6 isolates that produced large amounts of pyocyanin (>18ug/ml), were associated with SS, p = 0.014. Multivariate analysis indicated that the odds ratio (OR) for development of SS with a non-motile isolate was 6.8, with a 95% confidence interval (CI) (1.37, 51.5), p = 0.030 and with high pyocyanin producing isolates, an OR of 16.9, 95% CI = (2.27, 360), p = .017. This study evaluating the role of microbial factors that significantly effect outcomes following Pa bloodstream infection suggests that P. aeruginosa strains showing high pyocyanin production and the lack of motility independently increase the risk of SS.

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Solid organ transplant (SOT) recipients are at increased risk of opportunistic infections due to significant T-cell immune dysfunction. The incidence of clinical disseminated histoplasmosis is rare, and its variable clinical presentation and response to therapy make it challenging to treat with resultant high mortality. A high index of clinical suspicion is necessary, especially in non-endemic areas. We report our clinical experience treating a 63-year-old renal transplant patient on immunosuppressive therapy with late-onset acute miliary histoplasmosis initiated on liposomal amphotericin B (L-AmB).

A 48-year-old-man who returned from Panama 5 weeks prior presented with fever, dysuria, hematuria, flank pain, and suprapubic pain and was found to have a prostatic abscess. Abscess fluid obtained during transurethral drainage grew Burkholderia pseudomallei. Blood cultures remained negative, and imaging did not show any other visceral abscess. This presentation of primary prostatic melioidosis is extremely rare in this region. Keywords: Melioidosis; Burkholderia pseudomallei; Prostatic abscess; traveler-related disease, Meropenem; Trimethoprim-sulfamethoxazole

Aerococcus urinae is a gram-positive organism frequently found in the urinary tract. It is often mistaken for Streptococcus and Enterococcus based on its appearance. It commonly causes urinary tract infections but has rarely been associated with fatal infective endocarditis and sepsis. We present a case of Aerococcus urinae infective endocarditis and discuss echocardiographic imaging findings and management approach.