Pseudomonas Infection: A Clinical Case Discussion || || ||

[00:00:06]Welcome to ATSN, the Emergency Medicine channel. I'm Shalin Sasidharan.

[00:00:10]Presenting the case of a 70-year-old male who came to ER with complaints of fever since last 1 week, with cough with greenish expectation since the last 5 days. Along with breathing difficulty since last 5 days.

[00:00:24]>> Greenish sputum indicates what?

[00:00:26]Hm?

[00:00:27]>> Pseudomonas. Straightaway pseudomonas.

[00:00:30]>> Since this case is like that shows there is a chance of pseudomonas, but normally we all get sputum and it become yellow, green.

[00:00:39]Is there that pigment pigment produced >> It is a pigment produced by the neutrophils myeloperoxidase.

[00:00:45]>> Yes.

[00:00:45]>> That produces the color. Okay, that's all. It doesn't mean that it's always an infection, but pseudomonas also you can get greenish color.

[00:00:54]>> So, in initial 10-second assessment, the patient was conscious, oriented. He was speaking in full complete sentences. On assessment of the airway, the airway was patent. There was no pooling of secretions or any stridor or any gurgling sounds.

[00:01:06]On assessment of breathing, the patient had a saturation of 82% in room air.

[00:01:11]Along with that in with respiratory rate of 32 breaths per minute. And on assessment of the auscultation wise, there was bilateral creps allowing bilateral mammary inframammary scapula and interscapular region.

[00:01:26]And on assessment of the circulation part, the patient had a heart rate of 116 beats per minute with a um that capillary refill time less than 3 seconds and BP of 126 by 80 mm of mercury.

[00:01:42]And on assessment of the disability, the patient had GCS E4 V5 M6.

[00:01:46]Pupils are equal and reactive on size of 2 mm. And on assessment of the exposure, the patient's GRBS was 137 and there is no present temperature was 100° Fahrenheit.

[00:02:00]And on initial part as patient had a desaturation, we had only started we had kept him on a proper position and then we had started him on oxygen. We had started him on O2 mask actually initially. Before that before starting O2 mask, we had taken an ABG arterial blood gas of this patient. In ABG the patient had a type one respiratory failure with PAO2 of 45.

[00:02:22]With a pH was normal and the potassium was 3.1.

[00:02:29]And lactate was four.

[00:02:31]And so this is the finding which we had got and the following which >> [clears throat] >> we had again taken a CBC CRP point of care we had taken. In that the total counts were 17,000 with a CRP more than 230.

[00:02:46]ECG showed no acute it was normal. There was no acute STT changes.

[00:02:51]Following which we had again assessed the patient. We had asked the sample history of this patient. The patient was he was he had a chronic he was a 70-year-old male.

[00:03:05]So he comorbidities was he was a known case of type two diabetes.

[00:03:09]No other comorbidities. So he had a history of chronic exposure to smoke which was mainly along his nearby there was a like For a worship it was used. So there was increased exposure to smoke along that area. And so he mainly complains of no fever which has been there since last one week with cough with initially cough did not had expectoration but since the last five days now it has green color expectoration and it was it was very much copious amount it was present. And along with that the patient also had a breathing difficulty which has been Uh, it was a modified grade two to it has risen to grade four since the last 5 days. Uh, there is no history of any chest pain or any palpitation or any sweating or somnia PND for this patient. No history of any vomiting, loose stools for this patient.

[00:04:05]No history of any headache, there is no history of any altered sensory also for this patient. So, following which we had asked the past history and all he said prior to diabetes. Personal history, he has this exposure to smoke since last uh, like 1 month there has been increased to fire worship with big fire and Uh, this was the history which he had got and following which we had kept him on O2 mask. Uh, but >> [clears throat] >> when we checked the initial FIO F PAO2 by FAO ratio, the patient's PAO2 by FAO2 ratio was less than 100. It was 81. We had then increased that is which was taken in the room air. Then we had started him on oxygen. We had taken x-rays. X-rays showing bilateral infiltrates along bilateral middle lower zone with a right upper zone there was a presence of a gas a suspected cavity cavity. So, that time we had then proceeded to a CT chest for this patient. In that there was presence of traction bronchiectasis along along the right upper zone with bilateral ground glassing opacities and consensual changes.

[00:05:09]>> condition you get upper lobe bronchiectasis?

[00:05:12]>> It's mainly in cases of tuberculosis.

[00:05:15]>> TB TB is first most common.

[00:05:17]>> Uh, in case of Klebsiella in case >> Previous bacterial infection is predominantly Klebsiella, Pseudomonas >> Pseudomonas all those, yes.

[00:05:24]>> necrotizing pneumonia >> Yes, so this patient's >> Then other than that fungal infections then fungal infection also predominantly upper lobe.

[00:05:33]>> Yes, this patient they had gone to an outside hospital where they did a sputum culture which is showing positive for Pseudomonas aeruginosa. So, we had also taken >> Pseudomonas grows in bronchiectasis.

[00:05:46]>> Yeah.

[00:05:46]>> It can produce bronchiectasis, can also chronically grow in bronchiectasis.

[00:05:52]So, initially as per antibiotic management, we are initially started him on ceftriaxone with the nebulization of tobramycin.

[00:05:59]This was the initial management which we had started on this patient. Then progressively the patient's oxygen PO2 FIO2 ratio had increased to 150. So, he was maintaining in that form.

[00:06:12]We had also sent blood cultures and the urine culture along with repeat we had his expectation had decreased. So, we had to do a bronchoscopy and then we had taken a bile also for this condition.

[00:06:25]In the then the final in the blood culture the patient the pseudomonas growth was not present.

[00:06:33]In the sputum culture in our sputum culture there was no presence of pseudomonas growth. But in the urine there was presence of pseudomonas aeruginosa which was multi-drug resistant.

[00:06:43]So, patient's total count and CRP begin to increase. So, we are suspecting an MDR pseudomonas. So, initially we hiked the antibiotics from ceftriaxone to meropenem.

[00:06:54]Still which was not showing clinical improvement. We had done a PCR.

[00:06:59]>> What is ASBL?

[00:07:01]>> ASBL is extended spectrum beta-lactamase.

[00:07:04]>> What is the importance of this? This is MDR but sometimes you can see ASBL in your culture culture report. What does it mean?

[00:07:13]>> It will not be resistant it will not be sensitive to the like cephalosporins. Cephalosporins.

[00:07:18]>> But here the patient had responded to ceftriaxone and it has become negative and only urine shows it.

[00:07:24]>> Urine shows it.

[00:07:25]>> But in the urine sample it was all resistant to all these antibiotics. So, then we had to from meropenem also we had to hike it now to ceftazidime avibactam because we had done a repeat urine culture and that also it was showing XDR.

[00:07:39]>> Okay.

[00:07:39]>> That's extensive drug resistance.

[00:07:41]>> Okay.

[00:07:41]>> So, now patient is currently on ceftazidime avibactam antibiotic use.

[00:07:46]So, this is about that Pseudomonas variant. We had done a PCR. So, in the PCR now it is XDR Pseudomonas.

[00:07:52]So, the Pseudomonas is usually important in a ICU setup because we had managed him in the ICU after shifting in ICU because it causes the various issues.

[00:08:01]But, the first one is a in commonly it can cause bloodstream infections. It can also cause like catheter related infections, hospital acquired pneumonia, and also associated pneumonia. So, these are the complications which occur in Pseudomonas aeruginosa. And it is associated with high mortality. That's the main important thing. So, 20 to 50% of mortality is there in ICU patients.

[00:08:23]With rapid development of antimicrobial resistance. So, the first one we had treated with ceftriaxone, it became like like then it became new resistance had formed. So, this is the issue of Pseudomonas. And we are also practiced barrier nursing. patient because other patients can also get exposed to the same microbe.

[00:08:46]Following which >> What is this barrier nursing?

[00:08:49]He is talking about barrier nursing.

[00:08:53]Huh?

[00:08:54]No.

[00:08:56]Yeah. Here assigning one person to that patient so that that bacteria will not spread to other patient and that nurse should use all the barrier equipments.

[00:09:07]And whenever she go out here she has to remove it ideally.

[00:09:10]She cannot use it outside.

[00:09:12]>> Okay.

[00:09:13]>> So, then now I will be discussing about the various variants of Pseudomonas aeruginosa. So, variants are mainly involved. The first one is a wild type Pseudomonas. So, that's usually even wild type Pseudomonas is naturally resistant to many antibiotics. So, it produces different compounds like pyocyanin, elastase, phospholipase C and all. So, management mainly involves anti-Pseudomonas beta-lactamase. Only a single antibiotic will be necessary. It can be either piperacillin-tazobactam, cefepime, ceftazidime, meropenem, or imipenem.

[00:09:45]The next one is the mucoid Pseudomonas.

[00:09:47]So, that produces the alginate biofilm formation. So, this is usually that's why it can have resistance to the antibiotics. So, this is usually is commonly seen in bronchiectasis and cystic fibrosis patients and chronically ventilated patients. So, it For such patients, they require again a high-dose antipseudomonal therapy with beta-lactamase and also inhalational And the important thing is these antibiotics cannot penetrate some areas in the lungs.

[00:10:17]>> So, nebulization also >> Yeah, nebulization will be more effective in cases of such individuals.

[00:10:22]So, we can give them inhaled tobramycin. So, tobramycin is the preferred antibiotic in these patients. Then, we have the MDR Pseudomonas. So, MDR Pseudomonas is usually resistant to more than one agent in more than or more than or equal to three antimicrobial classes. So, usually such patients will be requiring different antibiotic combinations. The first one involves the ceftolozane-tazobactam and ceftazidime-avibactam. So, these are the antibiotics which are usually used. So, these are the combination therapy. Then, we have the XDR Pseudomonas. So, later we in our urine culture we have developed an XDR Pseudomonas. So, in XDR Pseudomonas also, the patient will require polymyxin B colistin. So, that is the last line which is the antibiotic to treat. Then, we have DTR Pseudomonas. That is a difficult to treat Pseudomonas infection. So, in such patients, the thing to notice that they will be resistant to piperacillin-tazobactam, cefepime, ceftazidime, aztreonam, meropenem, and even ciprofloxacin and levofloxacin also. And for such patients, we will have to the only drug is ceftazidime-avibactam.

[00:11:35]So in difficult-to-treat Pseudomonas also the drug is ceftazidime-avibactam.

[00:11:40]Then there is based on the genetic mechanism. There is AmpC hyperproducer.

[00:11:45]That is one type of Pseudomonas.

[00:11:47]For them they are usually resistant to third generation cephalosporins. So we can give meropenem for such patients.

[00:11:54]Then we have ESBL Pseudomonas. So ESBL Pseudomonas has mainly we the treatment in carbapenems because they will anyway be resistant to third generation cephalosporins. So we have to go for a carbapenem. For example, in our patient Our patient did not have an ESBL but in if >> XDR indirectly tells that that you may have ESBL.

[00:12:14]>> ESBL. So in such patients we go for carbapenem. So carbapenem is the treatment. Then we have the carbapenem-resistant Pseudomonas.

[00:12:23]So the time when we use the ceftazidime-avibactam.

[00:12:28]So that is the Then we have a very rare variants, three variants of Pseudomonas which are metallo-beta-lactamase producing strains. So there are VIM, IMP and NDM. So NDM is the New Delhi metalloprotease. So they are resistant to most of the beta-lactams. So the only treatment will become aztreonam-based combination. With aztreonam plus ceftazidime-avibactam. So that will be the combination in such patients.

[00:12:57]So this is usually seen in Pseudomonas.

[00:12:59]>> What do you understand from this?

[00:13:02]If you get a Pseudomonas in your ICU, what will you do?

[00:13:09]>> That anyway we'll be sending.

[00:13:11]>> As a doctor, what are you going to do? I am asking this.

[00:13:14]>> Start a dual antibiotic.

[00:13:15]>> Start dual antibiotics. One is like he told ceftazidime-avibactam or higher antibiotic like meropenem. If meropenem is resistant, then ceftazidime-avibactam. Second drug will be aminoglycoside.

[00:13:29]>> Aminoglycoside. If it is a lung infection, we always prefer to give nebulization. And quinolones also can be tried as second-line drug.

[00:13:38]And most important thing is You told no?

[00:13:41]>> Barrier nursing. We cannot spread this organism to next patient. Then it will be it will become a very costly affair in ICU. All patients will develop pseudomonas.

[00:13:51]That is the issue. Okay.

[00:13:54]Thank you. Thank you.