aka Microbial Mystery 002
Consider the following scenario:
A 27 year old female with metastatic ovarian cancer for whom curative options have been exhausted arrives in the emergency department in extremis. Her history is of rapid onset (over a few hours) of shortness of breath, high fevers and rigors. Her vital signs on arrival in the emergency department are as follows HR of 190, BP 80/30, RR of 65, temperature of 39 and saturations of 90% on 10L via face mask.
Questions
This patient is critically unwell and requires immediate assessment and resuscitation in an appropriately monitored environment. A team approach will be required and initial management should be directed towards establishing adequate airway, and stabilising breathing and circulation.
On the face of things this sounds bad. In a patient with metastatic cancer in whom all curative options have been exhausted it is necessary to weigh the burden of invasive treatment against the potential benefits; however, unless you can rapidly gain information from the patient, the patient’s family or someone else regarding limitations of therapy, it is better to address the immediate crisis now then ask questions later (in my view).
There are diffuse bilateral pulmonary infiltrates with air bronchograms visible.
The history and investigations strongly suggest that this patient has fulminant bacterial pneumonia with associated septic shock.
This picture of very rapid onset is typically seen with pneumococcal or staphylococcal pneumonia. It may also occur with Streptococcus pyogenes pneumonia but this is a relatively rare condition. Empirical antibiotics will vary according to local susceptibilities; however they should cover Pneumococcus (eg 2nd or 3rd generation cephalosporin) and Staph. including community acquired MRSA (eg clindamycin if local susceptibilities allow or linezolid or vancomycin). I would also cover atypical organisms with a macrolide in the first instance.
In this case, the diagnosis of pneumococcal pneumonia was confirmed by a positive urinary pneumococcal antigen:
A useful point here is that a patient with very rapid onset of severe bacterial infection who receives very rapid appropriate antibiotics can recovery rapidly.
About Paul Young
Great case. Why the amylase and CRP?
Not ordered by me! No good reason
Interestingly (or not…) CRP was discovered in 1930 by Tillet and Francis and was named C-reactive protein because it reacted with the C-polysaccharide of pneumococcus.
Thus we can expect it to be high in pneumococcal infections… for what its worth.
http://jem.rupress.org/cgi/reprint/52/4/561
I found the CRP comment very interesting.
Why a second or third gen cephalosporin? Non-PRP pneumococcus should be sensitive to most cephalosporins (excluding the gram-negative only ones like ceftazidime) and so cephazolin should be fine.
in fact, if you truly think that it is a gram positive pneumonia, I'd use something like 2g of cephazolin tds and 1g of vancomycin bd. Add azithromycin for atypical/legionella cover, and a decent dose of genta (6mg/kg). Compared to the standard regimen (1g of ceftriaxone + azithromycin) the H. influenzae cover probably isn't as good (although genta should be killing everything in sight).