Lit Review Mar #1
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 :).
Leading Photo by Suzanne Tucker on Unsplash
Trichinellosis Outbreak Linked to Consumption of Privately Raised Raw Boar Meat — California, 2017
https://www.cdc.gov/mmwr/volumes/67/wr/mm6708a3.htm?s_cid=mm6708a3_e
Not bear meat this time!
Initial patient and at least three family members evaluated for fever, myalgia, abdominal pain, diarrhea, and vomiting after attending a celebration where several pork dishes were served, including larb, a traditional Laotian raw pork dish (LARB DOESN’T HAVE TO BE RAW – I’ve never had a raw pork larb EVER)
lameda County Public Health Department (ACPHD) identified 29 individuals who attended the party and 7 more that consumed dishes brought home
Source of meat: domesticated wild boar raised and slaughtered on a private family farm
Tested for IgG: identified 10 confirmed and 2 probably cases (not lab confirmed)
Most got pretty sick (sepsis, AKI, GI bleeding) requiring ICU admission
Identified T. spiralis using touch prep slides confirmed by PCR and sequencing of ITS1-2 region
Owners of farm reported that small animals (chicks, etc) occasionally got into the pen and eaten by the pigs
Educated owners on meat processing (freezing for 30 days and cooking to internal temperature of 160°F (71.1°C))
Some patients said they would never eat raw meat again
One patient said he would continue to eat raw meat but from animals that he hunts, believing that raw meat confers strength
Increase in Hospital Admissions for Severe Influenza A/B among Travelers on Cruise Ships to Alaska, 2015
https://wwwnc.cdc.gov/eid/article/24/3/17-1378_article
Case report of lab-confirmed cluster of influenza (n=25) requiring hospital admission associated with cruise ships to Alaska during summer of 2015, admitted in an acute care center in Vancouver, mostly H3N2
7 tested positive on ship and started oseltamivir
1 tested negative on ship and did not receive treatment, although should have regardless of test results
Response due to surge in cases compared to same time in previous years
Only 4 people had been vaccinated
CDC recommendation on influenza on cruise ships
Crew and passengers should be vaccinated
Postpone travel when ill
Comply with respiratory etiquette and isolation
Initiate antiviral treatment in cases of confirmed or suspected influenza in ILI patients with severe manifestations or risk factors for severe disease
Interim Estimates of 2017–18 Seasonal Influenza Vaccine Effectiveness — United States, February 2018
https://www.cdc.gov/mmwr/volumes/67/wr/mm6706a2.htm
This year's flu vaccine effectiveness was 36% overall, 25% against H3N2, 67% against (H1N1)pdm09, and 42% against influenza B. Not that bad at all!
Invasive pulmonary aspergillosis and influenza co-infection in immunocompetent hosts: case reports and review of the literature
https://www.ncbi.nlm.nih.gov/pubmed/29454654
Report of 2 fatal cases of IPA in patients with flu A and flu B
Both relatively immunocompetent (one has poorly-controlled DM)
Positive for flu at admission, then developed respiratory failure and multi-organ failure afterwards
One had positive galactomannan, one didn’t
Autopsy confirmed IPA
Moral of the story: don’t ignore Aspergillus in severe flu patients
High Prevalence of Multidrug-Resistant Mycoplasma genitalium in Human Immunodeficiency Virus-Infected Men Who Have Sex With Men in Alabama
https://academic.oup.com/cid/article-pdf/66/5/796/23879834/cix853.pdf
Cause of up to 20% of nongonococcal urethritis, detected in 12% of MSM with proctitis
No FDA approved test
CDC recommendation: AZT as first line, MOX as second line
Looked at 157 HIV-infected MSMs over 2 years
Prevalence of M. genitalium infection was 17.2% (27 of 157)
10.8% urogenital
6.4% rectal
SO MUCH RESISTANCE – determined by Sanger sequencing
74.1% of all isolates (27) had mutations conferring macrolide resistance
80% of rectal samples and 70.6% of urogenital
29.6% had at least one typical parC fluoroquinolone-resistance mutation
40% of rectal samples and 26.7% of urogenital
24% had both
Delftia tsuruhatensis, an Emergent Opportunistic Healthcare-Associated Pathogen
https://wwwnc.cdc.gov/eid/article/24/3/16-0939_article
Another non-fermenter (SO MANY OF THEM) first isolated from sludge in Japan in 2003
Case report from France in ex 36 weeker with congenital cardiac anomaly requiring surgery, post-op complications included ARF, VAP
Bronch secretion grew this GNR and IDed by MALDI (Bruker) confirmed with 16S
AST using non-Enterobacteriaceae BPs and treated with CAZ, repeat culture negative
Review non-fermenter AST: NO DISK DIFFUSION BPs – BMD only
Non-Enterobacteriaceae for
Pseudomonas spp. (not P. aeruginosa)
Other nonfastidious, glucose-nonfermenting, GNRs except
Those with own BPs in M100: P. aeruginosa, Acinetobacter spp., B. cepacia, B. mallei, B. pseudomallei, and S. maltophilia
Those with BPs in M45: B. mallei, B. pseudomallei, Aeromonas spp., Vibrio spp.
VAP again a month later, this time MALDI mis-IDed as D. acidovorans, 16S confirmed correct ID (same bug as last time)
Treated with IPM, AMK, TOB but pt expired anyway
Reviewed records at institution: identified 11 patients, isolated from BCB, resp, urine
Most have underlying, including CVC, post-transplant, etc
All healthcare-associated
Invasive Infections Caused by Nannizziopsis spp. Molds in Immunocompromised Patients
https://wwwnc.cdc.gov/eid/article/24/3/17-0772_article
Phylum Ascomycota. previously reported as extremely rare cause of cerebral and disseminated infections
Case report from France again but different hospital
2 cases of cerebral abscesses in immunocompromised patients (leukemia and HIV)
One case positive BCB, another direct ITS PCR and sequencing positive in CSF followed by positive culture from cerebral biopsy
Seemed to have low MICs for most antifungals
One case passed away before positive BCB, the other got treated and improved
Both had recently spent time in Africa
High Cryptococcal Antigen Titers in Blood Are Predictive of Subclinical Cryptococcal Meningitis Among Human Immunodeficiency Virus-Infected Patients
Generally, it is believed that positive CrAg in blood is strongly predictive of subsequent cryptococcal meningitis in HIV patients with CD4<100
People have been using “screen-and-treat” approach before starting ART in pt with CD4 <100: tested forCrAg in blood
If positive in absence of meningitis: treat pre-emptively with fluc and maintained pending immune reconstitution with ART
Not super well supported, and many studies reported high mortality in these patients despite treatment
Possibility that asymptomatic or minimally symptomatic patients (a little bit of headache) with positive CrAg in blood could be having concurrent meningitis and there is no data for concurrent yet
Looked at over 505 HIV patients with CD4<100 and positive for CrAG in blood
50% no headache or confusion at all
34% headache only
15% confused only – excluded
Who actually had evidence of meningitis? Only LP would be able to tell, so among people who had LP done:
Asymp group: 34% had meningeal infection
Headache only: 90% had meningeal infection
What about CrAg positivity and titer in blood for these patients?
Among cases that had blood available for testing, blood CrAg titers significantly associated with concurrent meningeal infection in both groups
Best cutoff: blood CrAg titer >160, with sensitivity of 88.2% and specificity 82.1%
Not a whole lot of patients, but useful data: maybe people with positive CrAg in absence of symptoms should be treated more aggressively since they could already be having meningeal infection
Coccidioidomycosis Outbreaks, United States and Worldwide, 1940–2015
https://wwwnc.cdc.gov/eid/article/24/3/17-0623_article
Look at 47 outbreaks (>2 human coccidioidomycosis cases linked to a common source) all over the world involving >1400 patients
Most associated with environmental exposure (earthquakes – 1994 Northridge earthquake was part of this, dust storms)
>1/3 of cases occurred in area not know to be endemic for cocci
>1/2 occupational exposure (military, construction, archeology, labs)
Should increase awareness regardless of endemicity
Evidence for Previously Unidentified Sexual Transmission of Protozoan Parasites
https://wwwnc.cdc.gov/eid/article/24/3/17-1838_article
Parasites could reach seminal fluid from bloodstream to male genital tract or by directly infecting reproductive organ
Lit review: 5 parasite species with demonstrated presence in seminal fluid (doesn’t necessarily shown to transmit)
Entamoeba hystolytica: testicles, epididymis, and seminal fluid. Can cause damage and infertility, evidence of transmission
Schistosoma haematobium: migrate from bladder, no evidence of transmission
Trichomonas vaginalis: most common nonviral STI in the world and on the rise, associated with decreased sperm quality
Trypanosoma cruzi: found in chronically infected men, experimental mouse model demonstrated infection through intravaginal infusion of semen from infected humans
Toxoplasma gondii: also reported to affect sperm quality, experimental sheep model demonstrated infection after vaginal infusion of vegetative cysts
Protection of the Human Gut Microbiome From Antibiotics
https://academic.oup.com/jid/article/217/4/628/4653556
Free (not absorbed) antibiotics in lumen of intestine believed to have a negative effect on intestinal microbiome
A small study in 44 healthy volunteers to look at the effect of a new product (DAV132 – based on absorbent activated charcoal) on free fecal concentration of MXF after oral administration
Reduced free drug concentration by 99% while no effect on serum level
Metagenomic sequencing demonstrated preservation of composition of microbiota
The Impact of a Reported Penicillin Allergy on Surgical Site Infection Risk
https://academic.oup.com/cid/article/66/3/329/4372047
Fact: >90% of reported PEN allergy is not real
Looked at >8000 patients undergoing surgical procedures
Patients that reported PEN allergy had OR of developing surgical site infection of 1.5 compared to control
Associated with less administration of CFZ and more of second-line peri-op antibiotics including CLI, VAN, GEN
Significance of a more thorough evaluation of reported PEN allergy – pt missing out on getting effective prophylaxis
FDA OKs First Tests to Detect Tickborne Parasite in Whole Blood and Plasma
https://www.medscape.com/viewarticle/893546
Babesia: most frequently reported transfusion-transmitted parasitic infection, although still pretty uncommon
First screening tests for antibodies (using Arrayed Fluorescent Immunoassay (AFIA)) to Babesia microti in human plasma samples and B microti DNA (using NAAT) in human whole blood samples
Should reduce risk of transmission through blood transfusion
Pediatricians Should Know More About Lassa Virus
https://www.medscape.com/viewarticle/893469
CDC said clinicians should be able to recognize potential infection among children (mostly <10 yo) newly arrived in the United States from endemic areas (Guinea, Liberia, Nigeria and Sierra Leone)
Reservoir in rats, transmitted to humans via urine and feces
Person to person via body fluids
Incubation 1-3 weeks, may be asymptomatic, or starting with non-specific symptoms then develop viral hemorrhagic fever (VHF) leading to death
CDC performs serological and NAAT tests
https://jamanetwork.com/journals/jamapediatrics/fullarticle/2674042
Point-Counterpoint: Piperacillin-Tazobactam Should Be Used To Treat Infections with Extended-Spectrum-Beta-Lactamase-Positive Organisms
http://jcm.asm.org/content/56/3/e01917-17.full
Should we use BLBLIs for invasive infections caused by ESLB-harboring GNR?
Carbapenem-sparing regimens could use BLBLIs instead
Molecular technology detecting CTX-M available – clinical usefulness?
TZP is the most popular and still has decent activity against ESBLs, but some reports demonstrated reduced efficacy
May also depend on site and severity of infection
Difficult to compare studies because even in the same type of infection, sources may be different (CVC, pneumonia, GI/bile, etc)
UTI caused by ESBL: seems to be ok (as good as carbapenems) IF tested S
BSI: some previous conflicting results in small studies, but there was a recent big retrospective study in >200 patients – mortality than carbapenems
Most cases here had CVC source
CLSI does not recommend testing anymore if using new BPs for cephs and AZM, but since we want to use less carbapenems, should we start testing again?
Using CRO R is not adequate: so much diversity
Difficult to pick surrogate agent to test
These ESBLs could demonstrate variability on different test systems – even in BMD
How would lab report TZP: used to be an issue when ESBL detected
Maybe adding comments re: use in different types of infection would be helpful?
That's all for now. Bug Hunters, may the odds be ever in your favor.