Thread by @Floralquinolone

1/ You’re on rounds when a concerned fellow states “They aren’t clearing their bacteremia. It’s day 5 of therapeutic vancomycin and the daily blood cultures are STILL growing MRSA. What agents can we add on or change to clear this bacteremia?” #IDTwitter #NeoTwitter

2/ Is knowing they are a neonatology fellow, caring for a <30 wk GA, 2-week-old for a disseminated MRSA infection (+blood cx with MRI-confirmed osteomyelitis and a 10mm non-obstructive mass in the RA) enough information? How different can babies be from adults?

3/ A LOT different. As the article is titled “Neonates are not just little children”. Neonates have altered protein binding, larger volumes of distribution, smaller fat and muscle stores and immature kidney and liver function.

pubmed.ncbi.nlm.nih.gov/29745792/

4/ SAB in peds is a common reason for consulting peds ID. Like adults, vanc is the backbone of SAB when MRSA is present. Unlike adults, the approach to combination therapy is less well understood, especially in neonates.

Let's start with gentamicin!

pubmed.ncbi.nlm.nih.gov/32759380/

5/ The guidelines for IE in peds state adding gentamicin for the first few days may accelerate the killing of the Staph, but this is based on experimental models. One must consider the risk/benefit of accelerated killing to the combined nephrotoxicity.

pubmed.ncbi.nlm.nih.gov/26373317/

6/ Despite a lack of endorsement by guidelines for endocarditis without prosthetic material or as an adjunct to a persistent BSI, rifampin does have PK and limited outcomes data in clearing BSI’s in neonates.

ncbi.nlm.nih.gov/pmc/articles/P…

7/ TMP-SMX is not recommended in the neonatal period because of an increased risk of kernicterus as well as other options being available.

ncbi.nlm.nih.gov/pmc/articles/P…

8/ Any experience or preference with these options? #IDtwitter #neoTwitter

9/ While there is ample PK data on clindamycin dosing in neonates, a limitation to its use is local resistance rates. As an adjunctive for severe MRSA infections, there is ongoing research such as the CASSETTE trial and @snap_trial.

ncbi.nlm.nih.gov/pmc/articles/P…

10/ In a retrospective case series by Mohzari et al., in premature neonates, daptomycin at 6mg/kg BID was found to be safe and efficacious across a variety of Staph spp. not including Staph aureus. As for research in Staph aureus...

ncbi.nlm.nih.gov/pmc/articles/P…

11/ A case report by Chan et al. found using 6mg/kg BID daptomycin in a 28 week GA with a MRSA endovascular infection, to be tolerable and effective. CPK values remained normal throughout treatment, no seizure activity was seen.

pubmed.ncbi.nlm.nih.gov/31897079/

12/ Deville et al. compared linezolid to vancomycin, randomized 2:1, in a premature neonate population for a variety of gram-positive infections (SA and CoNS representing 84% of baseline pathogens). Bacteremia was the most common dx in both groups.

pubmed.ncbi.nlm.nih.gov/14520141/

13/ Linezolid at 10mg/kg q8h was as effective as vancomycin for neonates. As for tolerability, the only significant difference was seen in vancomycin causing more thrush than linezolid, but otherwise low incidence in adverse effects across the board.

14/ While there are no published studies evaluating ceftaroline in neonates for treating SAB. There is a case report exploring the drug's PK in a premature infant for MRSA pneumonia. The studied dose was 8.5 mg/kg every 8 hours over 2 hours.

pubmed.ncbi.nlm.nih.gov/29045693/

15/ This only scratches the surface of these adjunctive agents. No matter what approach you take, don’t underestimate the importance of decision-making as a multidisciplinary team and achieving adequate source control!

16/ Thank you @JVP_PharmD for mentoring me on my first tweetorial! #IDtwitter #neoTwitter