Pathogen Sleuths: what do you make of this?

[thenmama]

I'm putting on my detective cap right now, trying to determine what's going on with my ds and if it may provide new clues that will help us help him.

 

Recently ds had another PANDAS spike and his ped switched his abx to Bactrim for one course. He improved on it. Right at the end of that course when he was going back on Clinda, my dd, who'd been spiking, tested positive for strep again. The ped put everyone on a Clinda and Rifampin combo to try to wipe the strep out. Ds's PANDAS started to spike again when he switched meds. We rode it out in case it was situational or a short term side effect. He's finished the Rifampin now and back to his usual, pre-switch Clinda dose and he's still exploding and really miserable. I'm scratching my head about why an abx that's not typical for strep has worked better than what should be more successful-- since we know there've been strep issues, and dd is still dealing with them so he's been recently exposed.

 

Back at what we think was either his PANDAS onset or his first really significant exacerbation (almost 5 years ago), he'd had a long, ongoing series of infections including: ears, sinus, throat. Some of those infections were found to be caused by Moraxella Catarrhalis and one was caused by "nonfermenting gram negative rods" (not further identified, but noted it was not p. aeruginosa). He was treated with Septra for at least the gram neg infection (susceptibility panel was run). And I know he and dd were treated with Septra other times during that period with our old ped. He also tested pos for "heavy" Moraxella Catarrhalis growth with later infections. I began poking around and found this article about coaggregation (which seems relevant to our community): Moraxella catarrhalis Coaggregates with Streptococcus pyogenes and Modulates Interactions of S. pyogenes with Human Epithelial Cells

 

Does anyone know more about coaggregation? Or how about other pathogens that might respond better to Sulfa/Trimeth than the usual strep players? Anybody see some clues in this or does anything jump out at you? Am I missing something obvious... or obscure?

 

Unfortunately our ped is out for the rest of the week. I am going to try to see a different doc in the practice tomorrow in hopes they'll switch abx and/or start him on steroids til our doc returns. We're heading toward IVIG or PEX soon, as well.

 

TIA!