aka Pulmonary Puzzle 004
Consider a 56 year old male with no past medical history presenting with 10 days of fevers, chills, myalgias and cough followed by worsening breathlessness over the past 4 days.
His admission chest X-ray is shown below:
Q1. Describe the chest X-ray findings:
The chest X-ray demonstrates a dense alveolar infiltrate involving the lateral aspect of the left mid-zone.
The patient rapidly deteriorated with fulminant shock, multiorgan failure and worsening oxygenation.
The following chest ray is taken shortly after ICU admission:
Q2. What devices are present on the chest X-ray?
- right IJ central line
- left IJ vascath (dialysis catheter)
- nasogastric tube
- endotracheal tube
Q3. Which device is in the wrong place and where should it be?
The left IJ vascath is in too far.
Central lines and vascaths should not be inserted beyond the superior extent of the pericardial reflection (which corresponds to the take off of the right main bronchus) because beyond this point they can erode through the superior vena cava or the right atrium / ventricle leading to pericardial tamponade and death.
A subsequent chest X-ray is as follows:
Q4. What has happened since the previous chest x-ray?
A chest drain has been inserted draining the left pleural effusion and the vascath has been pulled back to an appropriate position.
The following microbiology is obtained:
|Respiratory Sputum||Liquid, blood stained
Moderate growth of normal URT flora
Heavy growth of Streptococcus pyogenes
|Blood Culture||Specimen: Venous
Growth of Gram positive cocci resembling streptococci in aerobic bottle after 1 day.
Isolate identified as Streptococcus pyogenes
Q5. What is the diagnosis?
The overwhelming evidence here points to a diagnosis of Streptococcus pyogenes pneumonia, bacteraemia and empyema!
The clinical history suggests the possibility of a bacterial infection complicating influenza and, indeed, this turned out to be the case:
Influenza may predispose to invasive group A Strep disease (at least it does in mice)
Q6. What is the prognosis?
In a series of 2079 cases .of invasive group A Strep infection, the case fatality rate was 38% for pneumonia, compared with 26% for patients with necrotizing fasciitis.