Good memory GerryW. The original study was cut short because some patients were, indeed, going down for nobvious reason. I was tangentially involved to the extent that I was visiting England long enough to provide an extra data point for their baseline but not long enough to take part. But I did get a free HP test (strong positive). As a result I developed a strong interest in HP vis a vis PD. It has been awhile but I think the following points should be noted-

1) HP can be one scarey bug. Its cell wall is made with a toxin (LPS) as part of its structure where it is harmless. Until the bug dies. One dead bug you have a tiny drop of LPS to detox. No problem. Drop a load of antibiotics in there and you have a trillion or so dead bugs and a problem. Possibly a deadly one depending your own detox ability and your own sensitivity to LPS.

2) Some strains of HP take it real personal and when they sense a rising antibiotic level they up there own LPS output in a darned "poison pill defence"! If you are eating something that causes HP a problem you probably blame it and not the HP and drop it from your menu. If you charge in with an antibiotic that kills the first time you have the problem in #1 above. HOWEVER, if you have inadequate antibiotics plus one of the nasty strains you may have a crippling or even fatal problem.

3) If that happens in the real world where you show up at your doc's door a few days later he can try other antibiotics. If you are in an early trial where none of this is yet known and you have months to go before you even know who got the placebo you are in trouble. Once that becomes clear then the researchers can deblind the study and do triage. But it takes time to learn this stuff.

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