Lit Review Feb #4
Disclaimer: this compilation of synopses have been collected from multiple sources, including Mark Crislip's Puscast, Journal Watch Infectious Diseases, Medscape Infectious Diseases, CDC MMWR, AMA Morning Rounds, ProMED Mail, Journal of Clinical Microbiology, Antimicrobial Agents and Chemotherapy, Clinical Infectious Diseases, and more. I chose these articles based on their relevance to clinical microbiology and would be of interest to my fellows, and some other pieces that I found amusing to read. All credit goes to these original contributors. I'm just a messenger :).
Drugs that reduce transmission of falciparum malaria
http://www.thelancet.com/journals/laninf/article/PIIS1473-3099(18)30070-7/fulltext
Current artemisinin-containing regimens and alternative sulfadoxine-pyrimethamine /amodiaquine combination reduce gametocyte development, but do not have effect on existing mature PF gametocytes that are ready to infect mosquitoes at time of initiation of treatment
Primaquine and methylene blue have potent PF gametocidal effects, administered orally
High dose of primaquine can induce hemolysis I G6PD patients, but single low dose is ok
MB is pretty safe, administer in a 3-day course
Use of either, combined with standard regimens reduced transmission completely at day 2
The only side effect is with MB (blue pee)
New HBV vaccine Recommended by Advisory Committee on Immunization Practices
https://apnews.com/028195fb92054ea5b4370e5c800509de/US-panel-recommends-new-adult-vaccine-against-hepatitis-B
Heplisav-B: the first new hepatitis B vaccine in 25 years.
Given in two shots over a month, as opposed to regimen of three doses over six months
Notes from the Field: Increase in Acute Hepatitis B Infections — Pasco County, Florida, 2011–2016
https://www.cdc.gov/mmwr/volumes/67/wr/mm6707a6.htm?s_cid=mm6707a6_e
From 2011 to 2016: number of acute HBV-infected persons in Pasco County increased from 1.5 to 17.28 per 100,000 residents (p<0.001)
More than half reported injection drug use in the 6 months preceding symptom onset
HIV?
WHO Announces Recommended Components of 2018–19 Flu Vaccine
http://www.who.int/influenza/vaccines/virus/recommendations/2018_19_north/en/
For 2018–19 season in the northern hemisphere
An A/Michigan/45/2015 (H1N1)pdm09-like virus
An A/Singapore/INFIMH-16-0019/2016 (H3N2)-like virus
Switched from an A/Hong Kong/4801/2014 (H3N2)-like virus due to lack of efficacy
A B/Colorado/06/2017-like virus (B/Victoria/2/87 lineage)
Switched from a B/Brisbane/60/2008-like (B/Victoria lineage) due to genetic changes in circulating viruses
A B/Phuket/3073/2013-like virus (B/Yamagata/16/88 lineage)
Omitted in trivalent vaccines
Neonatal Immunization with a Novel Vaccine Against Rotavirus
http://www.nejm.org/doi/10.1056/NEJMoa1706804
Novel RV3-BB vaccine: strain RV3 (isolated from asymptomatic infants, natural infection with this virus is associated with prevention of GE for 3 years)
Study in >1500 infants in Indonesia
Four doses the followed for 18 months
Vaccine efficacy: 75% (neonatal schedule - 0 to 5 days, 8 weeks, and 14 weeks of age), 51% (infant schedule - 8 weeks, 14 weeks, and 18 weeks of age), and 63% (overall)
Time to first gastroenteritis significantly longer among vaccine recipients compared with placebo
No intussusception occurred during standard 21-day risk period
Rotavirus vaccination in neonates thought to be meh due to possibility of low vaccine strain binding in immature gut and immature immune system, but this proved otherwise
Evaluation of the association between the concentrations of key vaginal bacteria and the increased risk of HIV acquisition in African women from five cohorts: a nested case-control study
https://www.sciencedirect.com/science/article/pii/S1473309918300586?via%3Dihub
Case-control study in 349 women in sub-Saharan Africa with or without HIV
Vaginal samples collected and follow-up for HIV acquisition
16S metagenomics, bacteria-specific PCR
55 acquired HIV, compared with 55 control cases
Lower relative abundance of Lactobacillus iners associated with higher probability of HIV acquisition
Higher relative abundance of these organisms associated with higher probability of HIV acquisition
Parvimonas species type 1 and type 2
Gemella asaccharolytica
Mycoplasma hominis
Leptotrichia/Sneathia
Eggerthella species type 1
Megasphaera
Nugent score of 7-10 associated with twice risk of HIV acquisition compared to lower scores
Probiotics to prevent transmission?
Strains of bacterial species induce a greatly varied acute adaptive immune response: The contribution of the accessory genome
http://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1006726
Why do clinical courses of infection vary between individuals?
Differences in bacteria vs host immune responses?
Study of acute adaptive T- and B-cell immune responses induced ex vivo by various Staphylococcus aureus (16) and Streptococcus pyogenes (3) strains using lymphocytes isolated from 11 healthy individuals
Evaluated acute adaptive immune responses (T- and B-cell mediated)
A lot of variability in strength of immune responses between strains, but strength of responses of same strain among individuals was pretty similar
The bacteria itself may have more effect on immune response (rather than host)
Knocking out accessory genomes (leaving “core” genome): blunted immune responses
Maybe it’s the accessory genome that matters
May contain unique combination of virulence determinants and superantigens
Culture-Negative Septic Shock Compared With Culture-Positive Septic Shock: A Retrospective Cohort Study
https://insights.ovid.com/crossref?an=00003246-900000000-96384
Studied clinical characteristics and outcomes of culture-negative septic shock (2651) in comparison with culture-positive septic shock (6019)
Survival and severity of disease (per Acute Physiology and Chronic Health Evaluation II - APACHE II scores) similar among groups
https://www.mdcalc.com/apache-ii-score
Delay in antimicrobial treatment negatively affected mortality in both groups
Moral of the story: the most important thing is to recognize clinical sepsis and initiate early appropriate antimicrobial therapy regardless of culture results
Topical Antibiotic Use Coselects for the Carriage of Mobile Genetic Elements Conferring Resistance to Unrelated Antimicrobials in Staphylococcus aureus
http://aac.asm.org/content/62/2/e02000-17
New Zealand: unrestricted use of mupirocin and fusidic acid (in the 90s) associated with increase in isolates with high levels of resistance (to 28%) in 2015 – among the highest in the world
ST5 MRSA, ST1 MRSA, ST1 MSSA seemed to predominate
This study looked at ST1 isolates
WGS
fusC on chromosome and mupA on plasmid, but both in mobile genetic element cassettes
BEAST timed phylogeny: expansion of strains harboring mupA occurred same time as initiation of clinical use of mupirocin in the early 90s, also co-selects for isolates harboring fusc, which experienced another expansion shortly after fusidic acid became available in the late 90s-early 2000s
Cost-effectiveness of Bezlotoxumab Compared With Placebo for the Prevention of Recurrent Clostridium difficile Infection
https://academic.oup.com/cid/article/66/3/355/4587924
Human monoclonal antibody directed against the toxin B (Bezlotoxumab) implicated in prevention of CDI recurrence in patients receiving antibiotic therapy for CDI
Cost-effectiveness study using data from 2 RCTs (comparing outcomes between SOC and giving Mab along with antibiotics to treat CDI) and computer models
Use of mab
Reduced first recurrence by 10.1%, total recurrences by 16.7%, and 180-day mortality by 1.1%
0.12 quality-adjusted life-years (QALYs – 1 QALY equivalent of one year in perfect health) gained
Saved money! $2,444/pt, with incremental cost-effectiveness ratios (ICERs – cost of treatment to gain one QALY) $19824/QALY gained
Even better (save more money, less ICERs) in pt older than 65 or immunocompromised
Reduction in Rate of Nosocomial Respiratory Virus Infections in a Children’s Hospital Associated With Enhanced Isolation Precautions
https://www.cambridge.org/core/journals/infection-control-and-hospital-epidemiology/article/reduction-in-rate-of-nosocomial-respiratory-virus-infections-in-a-childrens-hospital-associated-with-enhanced-isolation-precautions/A1A9A96B004539DF8A4255B5B86F8D94
Current CDC recommendations for respiratory viral infections/viruses transmitted through respiratory tract
Airborne + droplet + contact + standard: SARS
Airborne + contact + standard: VZV, Monkeypox , Smallpox
Airborne + standard: Measles
Droplet + contact + standard: Adenovirus
Droplet + standard: Influenza, Mumps, Parvovirus B19, Rhinovirus, Rubella (not congenital)
Contact + standard: RSV, Parainfluenza, HMPV, Enterovirus (children)
Standard: Enterovirus (adults), Hantavirus
Generally if not covered: children – contact + standard, adults – standard
https://www.cdc.gov/infectioncontrol/pdf/guidelines/isolation-guidelines.pdf
A study in a children’s hospital over 4 years in NY among RTI
2 years of HICPAC recommendation, followed by 2 years of droplet + contact + standard for everybody
When using all 3, nosocomial viral RTI decreased 39% from 0.827/1,000 hospital days to 0.508/1,000 (P<.0013)
Excluding rhinovirus/entero: decreased 58% from 0.317 per 1,000 hospital days to 0.134 per 1,000 hospital days during enhanced precautions (P<.0014)
Nasal Flu Vaccine Back on CDC List of Recommended Vaccines
https://www.medscape.com/viewarticle/892970
Advisory Committee on Immunization Practices (ACIP) voted to bring back recommendation for nasal live attenuated influenza quadrivalent (different strains from inactivated) for the 2018-2019 influenza season, after rejecting it the last 2 years due to poor efficacy against circulating H1N1 strains
Found to be quite as effective as inactivated vaccine against flu B and H3N2
H1N1 strain was changed and found to be more effective
Give people options instead of not vaccinated at all
Association of Vegetation Size With Embolic Risk in Patients With Infective Endocarditis
https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2672577
Meta-analysis involving 5116 vegetations with available dimensions
Patients with vegetation size > 10 mm had increased odds of embolic events (OR, 2.28; 95% CI, 1.71-3.05; P < .001) and mortality (OR, 1.63; 95% CI, 1.13-2.35; P = .009) compared with those with vegetation size < 10 mm
Helps with risk stratification: which patients should be promptly referred for higher level of care
Emergence of an Extensively Drug-Resistant Salmonella enterica Serovar Typhi Clone Harboring a Promiscuous Plasmid Encoding Resistance to Fluoroquinolones and Third-Generation Cephalosporins
http://mbio.asm.org/content/9/1/e00105-18.abstract
Multidrug-resistant (MDR) S. typhi are prevalent in parts of Asia and Africa, often associated with dominant H58 haplotype
Widespread FQ resistance, with sporatic 3rd gen ceph and macrolide (AZT) resistance
Identification of clonal expansion of a XDR strain (also H58, MDR – 1st line drugs: chloramphenicol, ampicillin, trimethoprim-sulfamethoxazole PLUS fluoroquinolones, and third-generation cephalosporins) in Pakistan and a traveler in UK
WGS: some elements common to H58 – chromosomal cassette containing catA1, blaTEM-1, dfrA7, sul1, sul2, strA, strB, gyrA mutation (only I to FQ)
AND plasmid-mediated blaCTX-M-15 (3rd gen ceph) and qnrS (R to FQ)
On IncY plasmid, which was found in other enteric bacteria isolated from widely distributed geographic locations
Infrequent Testing of Women for Rectal Chlamydia and Gonorrhea in the United States
https://www.ncbi.nlm.nih.gov/pubmed/29028971
Anal sex: 35.9% of women aged 18–44 years reported to have had anal sex
CDC does not recommend testing at this time, but how many are positive?
Mucosal inflammation caused by NG/CT also increased risk of HIV transmission in women
A study with 7.9 million women tested for NG/CT by NAAT
Only 0.1% had rectal results, 0.5% had pharyngeal results
Among those that had rectal results (5499)
8.0% CT+ only, 2.0% GC+ only, 0.8% both +
Rectal CT positivity significantly (P < .05) higher for women aged 15–24 years compared to older
+CT from rectal specimens was never repeated
46.5% of rectal CT and GC infections would not have been identified with genital testing alone
Utility of testing for/treatment of rectal NG/CT in high-risk women?
Incidence, Etiology, and Outcomes of Community- Acquired Pneumonia: A Population-Based Study
https://academic.oup.com/ofid/article/5/2/ofy010/4844908
A study in Iceland looking at 310 CAP admissions, included cases where adequate sputum was not obtained
S. pneumoniae was the most common pathogen (61 of 310, 20%; incidence: 4.1/10000)
Viruses 15% (47 of 310; incidence: 3.1/10000)
M. pneumoniae 12% (36 of 310; incidence: 2.4/10000)
Multiple pathogens 10%
Antibiotics for uncomplicated skin abscesses: systematic review and network meta-analysis
http://bmjopen.bmj.com/content/8/2/e020991
Do we need to give antibiotics?
Meta-analysis looking at >3500 patients with skin abscesses: furuncles (boils) and carbuncles
Compared with or without antibiotics (on top of surgical)
TMP-SMX or clindamycin may confer modest benefit for treatment success, recurrence or hospitalization (not super awesome evidence), but definitely offset risk of adverse effects especially GI
CLN: higher risk of diarrhea than SXT
Cephalosporins probably not effective
Actinotignum schaalii Infection: A Clandestine Cause of Sterile Pyuria
https://academic.oup.com/ofid/article/5/2/ofy015/4848651
A. schaalii (formerly named Actinobaculum schaalii): small, Gram-positive coccoid rod, part of NF. In 1997
Difficult to ID in urine and mostly overlooked since resemble corynes
16s rDNA sequencing and/or MALDI
Grows slowly in 5% CO2 or anaerobically, catalase, oxidase, and nitrate
Uniformly susceptible to beta-lactam, but almost always resistant to SXT and FQ
Reported as cause of UTI especially in elderly and in those with underlying urologic conditions
Case report: 73yo M with recurrent epididymitis but negative urine cultures despite pyuria, treatment failure with FQ, then first positive culture IDed as G. vaginalis (based on GS morph, slow growing anaerobically, and hip +) and not treated, later IDed by Vitek-2 and MALDI, successfully treated with doxy
Mycobacterium abscessus Complex Infections: A Retrospective Cohort Study
https://academic.oup.com/ofid/article/5/2/ofy022/4848653
Rapid growers: becoming increasingly important
M. abscessus: higher mortality than any other rapid growers, usually resistant, commonly found in environment
Diff from M. chelonae: MA – NaCl+, citrate- while MC – NaCl-, citrate+
Types of infection: post-surgery or medical procedures, accidental injury where the wound is contaminated by soil, post-transplantation and cancer
Study in FL looking at 108 cases
Mostly respiratory infection
Most patients have ESRD, on immunosuppressives, or chronic lung diseases
Mostly S to CLR, AMK, TGC but all R to SXT and mostly R to CIP
Overall in-hospital MR 15.7%
Macrolide resistance, immunosuppression, and renal disease associated with early treatment failure
That's all for now. Bug Hunters, may the odds be ever in your favor.