Heck, to this day, my PA is still sensitive to Tobi and Cipro. Azithro, too, but I'm not on it regularly. PA is tricky. Eradication may fail for many reasons, such as repeated exposure or the PA forming biofilms very shortly after entering the lungs. To the original poster: That is what leads to colonization, by the way. Once there are biofilms, it's basically impossible to get rid of PA, since there are always some bacteria "cocooned away" in the film that aren't being exposed to the antibiotics, since they don't penetrate the films pretty much at all. However, one failed attempt at eradicating PA doesn't mean it's there to stay necessarily. I mean, yeah, ideally you'd like it to be knocked out after the first attempt, but most doctors make at least a subsequent attempt and my understanding is that 3 successive cultures with PA is when it's time to start suppressing them rather than trying to eradicate.
And a biofilm is? I think I know which bio-film you are referring to but there are more than one to penetrate sometimes. If you could explain more, it would be very helpful.
My favorite biofilm is a kind of chitin or bug shell material. The same material forming the exoskeleton on a beetle delayed the discovery of tuberculosis. This isn't necessarily the bio-film to be further explained but chitin armors the bacillus that is TB and Gram's staining will not penetrate its shell. Niether was anything else stainig or otherwise making it visable under a microscope. Robert Koch, the father of microbiology, left his dirty dishes, and reagents open over a short holiday. Another fall in crap, come out smelling like a rose discovery that changed the world. One common reagent in a bug growers arsenal then was carbolic acid, killer of everything. It didn't kill the TB bacillus but etched away their armor. Koch stained some of this leftover mess and beauty of beauties it was there. The bacteria with incomplete shells revealed the chitin stealth structure. This little bio-film protected the biggest bacterial killer of people ever. TB carbuncles or chrysalis inside Egyptian mummies are common in the spine and bones as well as bog mummies' lungs. Six thousand years ago nearly everybody had TB and most eventually succumbed.
No single antibiotic fully kills all TB because of this bio-film. Penicillin hardly touches it and as far as I know has never been used in a drug therapy eradicating TB. At first there was just one antibiotic type, sulfa based antibiotics came before discovering the battle between different microbe families likes yeasts, bacterias and molds. This chemical warfare gave us the idea to grow large amounts of each family, extract their chemical weapons and see what the did to pathogenic bacteria and to us. Penicillin was just that. The sweat loamy smell of fertile soil is volitile gases, warefare agent of the mycelium mold farts are the basis of modern antibiotics and a deep breath of that fecund gold not only grows our food but hold the answers to aid us fight bacterial infections. Streptomycin was antibiotic number two in the calculus of curing TB infection. The first sufa ring, a ring like chemical structure like a benzene radical was discovered during a boming raid on Bayer during WWI and it was based on a red fabric dye, a mainstay of Bayee before war. It turned the patient red in curing a bacterial infection. Better red than dead they said.
I am going somewhere with this so please hang on. Rene Dubois refined and perfected the sulfa antibiotic replacing Domagk's bright red Prontocil as one of the two in the search for a protocol. I can't recall the third antibiotic family but it might be a yeast's war tools. It is important to know three antibiotic families, defined by their source as penicillium mold to extract the antibiotic weapon penicillin. Streptomycin was found in a mycelium fungus. Tetracycline has that "cycline" suffix in another antibiotic family and a drug like cipro is a tetrocycline or "cycline" drug. The third antibiotic family needed one invention to cure TB. An English physician/researcher invented the modern MAT.
The MAT was needed for up to a year of three or more concomitant antibiotics, massively broad spectrum antibiotics to the date were needed for eradicating a bio-filmed bug confidently. That confidence was quickly shattered the first time a patient discontinued MAT prematurely as they felt quit well at some point. This made the first MDR resistant TB bacillus a social disease. Social workers were behind compliance. Noncompliance was first addressed over MAT treated patients. At first it was deadly serious and isolation in a hospital was the alternative. Great idea if it simlpy for a week. As expensive as it was, to sequster a person generally in a fenced in medical facility for a year or even a six month isolation was hard on families. What surprises me I guess, is MAT is a protocol that largely unchanged in over 60 years.
LL
P.S. pseudomomous auria is abbreviated Pa to my knowledge. PA is another, simpler metobolic error in amino acid replacement. Simple but fatal. I went right down a rabbit trail about when propionic acid is made due to a gene error and the four metabolic chemicals stop and cells die without the energy to live. If my use of Pa not PA is in error, post what means what for CF.
LL
