No Rosetta Stone Needed
Mark Crislip
The patient, vaccinated, is admitted with SOB, a positive COVID test and is intubated. Interesting CXR on admit: a left lower lobe consolidation somewhat obscured by the heart., Not your typical COVID presentation, but over the next several days the CXR changes to a more typical pattern for COVID, but the lll consolidation persists.
Also, on admission, one of two blood cultures grows a S. anginosis and for that gets a two-week course of ceftriaxone in addition to dexamethasone and baricitinib. Three weeks later, the patient is not getting better, so as part of the evaluation, a chest CT is performed. Performed. Like it is a one-act play. But it does show a necrotizing lll abscesses, and I am called.
This was a Hickam's dictum case. The patient presented with two processes. COVID and a lung abscess and the first diagnosis obscured the second. Ye Olde Premature Closure. You know the abscess was present on admission because of the blood culture. When the S. anginosis group (S. anginosus, S. intermedius, and S. constellatus) are in the blood, the question which should be asked, and wasn't, is where is the abscess?
Because these are the abscess causing Streptococci.
The answer was in the lll, but no one looked.
I figure that there are questions three every consult should ask: what is the infection, what is the treatment, and what is the airspeed of a... no, the third is why is there an infection at all.
As I have said many a time, the name of the bacteria will often tell you why. If you understand the significance of the organism.
Exam and history also supported the diagnosis: very poor dentition and a heavy drinker.
This is a classic aspiration pneumonia—the real deal.
I do not know about your institution, but somewhere along the line, an aspiration pneumonia - lung abscess/empyema in an alcoholic/seizure/heroin user with poor dentition - became conflated with aspiration events. People have looked. For acute aspiration events, be it community, hospital, or ventilator, there are no anaerobes as part of acute aspiration and subsequent pneumonitis. But metronidazole keeps being given for acute aspirations. As if antibiotics help in acute aspiration:
Prophylactic antimicrobial therapy for patients with acute aspiration pneumonitis does not offer clinical benefit and may generate antibiotic selective pressures that results in the need for escalation of antibiotic therapy among those who develop aspiration pneumonia.
If you want to practice medicine unhinged from reality, be Ron DeSantis's Surgeon General.
There is a certain irony. For years, I have been grumping that an aspiration event is not an aspiration pneumonia, and metronidazole is not only not needed, but it also goes against the entire medical literature. Then a classic case is admitted, not recognized, and the needed metronidazole, in addition to the Streptococcal coverage, is not given.
Sigh.
Rationalization
Clin Infect Dis .2018 Aug 1;67(4):513-518. doi: 10.1093/cid/ciy120. Prophylactic Antimicrobial Therapy for Acute Aspiration Pneumonitis https://pubmed.ncbi.nlm.nih.gov/29438467/
Diagnostic Error in Internal Medicine https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/486642