What’s New in ID? June 2019 / Lipanj 2019.

IDSA guidelines on asymptomatic bacteriuria (June 2019)

The Infectious Diseases Society of America recently released updated guidelines on asymptomatic bacteriuria, which include discussion of populations not previously addressed. These guidelines recommend against screening for or treating asymptomatic bacteriuria in most children and adults, even in those with underlying conditions such as diabetes mellitus, spinal cord injury, and immunosuppression. Exceptions include pregnant women and individuals undergoing urologic procedures with expected mucosal trauma, among whom screening and targeted therapy for positive cultures are recommended. Our recommendations are largely consistent with these guidelines.

 

Nicolle LE, Gupta K, Bradley SF, Colgan R, DeMuri GP, Drekonja D, Eckert LO,Geerlings SE, Köves B, Hooton TM, Juthani-Mehta M, Knight SL, Saint S, Schaeffer AJ, Trautner B, Wullt B, Siemieniuk R. Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America. Clin Infect Dis. 2019 Mar 21. pii: ciy1121. doi:10.1093/cid/ciy1121. PubMed PMID: 30895288.

 

PCR-based assay for diagnosis of bacteremia (May 2019)

Assays that detect bacterial DNA may be more efficient than blood cultures for identifying bacteremia. A study in more than 1400 patients with suspected bacteremia or sepsis tested a new polymerase chain reaction (PCR)-based assay capable of detecting five organisms (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli) [4]. Compared with blood cultures obtained simultaneously, the PCR-based assay had a shorter mean time to species identification (four to eight hours versus two to three days); the sensitivity and specificity of the PCR-based assay for patients with positive blood cultures were 90 percent. The PCR-based assay could be a useful adjunct to blood cultures for the diagnosis of bacteremia, but blood culture isolates are still required for sensitivity testing. Further study is needed to evaluate whether the use of this assay impacts outcomes such as survival, time to clinical improvement, or length of hospital stay.

Nguyen MH, Clancy CJ, Pasculle AW, Pappas PG, Alangaden G, Pankey GA, Schmitt BH, Rasool A, Weinstein MP, Widen R, Hernandez DR, Wolk DM, Walsh TJ, Perfect JR, Wilson MN, Mylonakis E. Performance of the T2Bacteria Panel for Diagnosing Bloodstream Infections: A Diagnostic Accuracy Study. Ann Intern Med. 2019 May 14. doi: 10.7326/M18-2772. [Epub ahead of print] PubMed PMID: 31083728.

 

Broadly neutralizing monoclonal antibodies for HIV (June 2019)

Broadly neutralizing monoclonal antibodies (bNAbs) are being explored as a novel therapeutic alternative or adjunct to antiretroviral therapy (ART) for patients with HIV infection. In earlier studies, HIV-specific bNAbs in the absence of suppressive ART resulted in viral rebound and rapid selection of resistant HIV. However, in a recent study of virologically suppressed patients, administration of a different bNAb (UB-241), which blocks the virus-binding site on CD4 cells, resulted in maintenance of virologic suppression during an 8- to 16-week period of ART interruption. Approximately 25 percent experienced viral blips (<150 copies/mL), although the clinical significance of this is unclear. Despite the apparent antiviral activity of this bNAb, there is no clear leading candidate or strategy for bNAb-based therapy, and its eventual role in clinical practice remains uncertain.)

 

Wang CY, Wong WW, Tsai HC, Chen YH, Kuo BS, Lynn S, Blazkova J, Clarridge KE, Su HW, Lin CY, Tseng FC, Lai A, Yang FH, Lin CH, Tseng W, Lin HY, Finstad CL, Wong-Staal F, Hanson CV, Chun TW, Liao MJ. Effect of Anti-CD4 Antibody UB-421 on HIV-1 Rebound after Treatment Interruption. N Engl J Med. 2019 Apr 18;380(16):1535-1545. doi: 10.1056/NEJMoa1802264. PubMed PMID: 30995373.

 

 

Immune checkpoint inhibitors and progressive multifocal leukoencephalopathy (May 2019)

There is no specific treatment for progressive multifocal leukoencephalopathy (PML). In several recent reports of patients with PML, immune checkpoint inhibitor therapy with nivolumab or pembrolizumab was associated with clinical improvement or stabilization in 7 of 10 patients. However, PML has developed after treatment with nivolumab in other reports. Further studies are needed to determine whether immune checkpoint inhibitors have a role in the treatment of PML.

Cortese I, Muranski P, Enose-Akahata Y, Ha SK, Smith B, Monaco M, Ryschkewitsch C, Major EO, Ohayon J, Schindler MK, Beck E, Reoma LB, Jacobson S, Reich DS, Nath A. Pembrolizumab Treatment for Progressive Multifocal Leukoencephalopathy. N Engl J Med. 2019 Apr 25;380(17):1597-1605. doi:10.1056/NEJMoa1815039. Epub 2019 Apr 10. PubMed PMID: 30969503.

 

 

Maternal TDF for HBV infection and fetal bone density (May 2019)

For pregnant women with hepatitis B virus (HBV) infection and high viral loads, tenofovir disoproxil fumarate (TDF) is recommended during the third trimester to reduce the risk of perinatal HBV transmission (in addition to passive-active immunization of newborns). There have been concerns about maternal use of TDF on fetal growth and development since TDF is associated with decreased bone mineral density; however, data are generally reassuring. In a randomized trial of pregnant women with HBV monoinfection, use of TDF from 28 weeks gestational age to two months postpartum had no effect on maternal or infant bone density one year after delivery compared with placebo. These findings support current recommendations to prevent perinatal transmission. Although a newer formulation of tenofovir, tenofovir alafenamide, has less bone toxicity compared with TDF, we do not use tenofovir alafenamide during pregnancy given the lack of sufficient safety data.

 

Salvadori N, Fan B, Teeyasoontranon W, Ngo-Giang-Huong N, Phanomcheong S,

Luvira A, Puangsombat A, Suwannarat A, Srirompotong U, Putiyanun C, Cressey TR,Decker L, Khamduang W, Harrison L, Tierney C, Shepherd JA, Kourtis AP, Bulterys M, Siberry GK, Jourdain G. Maternal and Infant Bone Mineral Density 1 Year After Delivery in a Randomized, Controlled Trial of Maternal Tenofovir Disoproxil Fumarate to Prevent Mother-to-child Transmission of Hepatitis B Virus. Clin Infect Dis. 2019 Mar 29. pii: ciy982. doi: 10.1093/cid/ciy982. [Epub ahead of print] PubMed PMID: 30924492.

 

 

Procalcitonin-guided algorithms versus clinical assessment for pneumonia (May 2019)

Several clinical trials among patients with community-acquired pneumonia (CAP) have shown that procalcitonin-guided algorithms reduce unnecessary antibiotic use compared with usual care. However, in many of these trials, usual care was not standardized or protocol-driven. In a randomized trial evaluating 285 patients with presumed CAP in 12 medical centers, antibiotic duration was similar when guided by procalcitonin versus serial protocol-driven clinical assessment (10 versus 9 days). Clinical success and adverse event rates did not differ between groups. This study calls into question the additive value of procalcitonin beyond careful clinical assessment and highlights the importance of critically thinking about appropriateness when deciding to prescribe antibiotics.

 

Montassier E, Javaudin F, Moustafa F, Nandjou D, Maignan M, Hardouin JB,

Annoot C, Ogielska M, Orer PL, Schotté T, Bouget J, Agha Babaei S, Raynal PA, Eche A, Duc AT, Cojocaru RA, Benaouicha N, Potel G, Batard E, Talan DA. Guideline-Based Clinical Assessment Versus Procalcitonin-Guided Antibiotic Use in Pneumonia: A Pragmatic Randomized Trial. Ann Emerg Med. 2019 Apr 11. pii:S0196-0644(19)30147-7. doi: 10.1016/j.annemergmed.2019.02.025. [Epub ahead of print] PubMed PMID: 30982631.

 

Source: UpToDate, June 2019.