Feline pyothorax

Question
Hi,  my 11 year old cat passed away this week at the Emergency Vet office.  I took him there because he appeared to be having trouble breathing.  He had been acting normal and had a normal appetite.  He went into cardiac arrest while they were taking XRays.  Fluid tests showed that he had large amounts of pus in the lung cavity.  He was an indoor cat but ventured out occasionally during daytime hours.  About 7 months ago, he was attacked by an unneutered male cat in the neighborhood. He had a wound on his foot which later healed without abscess.  I did not take him to the doctor so he didn't have any antibiotics.  Do you think the infection in the lung cavity could have been caused by the attack he suffered 7 months ago?  Thanks for your help!

Answer
With pylothorax unfortunately the original cause often is not found some of the more common is a bite that penetrates the chest, associated Feline Leukemia or FIV and dental disease.  Given that the previous bite was 7 months ago and in a distal limb, it seems rather unlikely to have been the cause, though I cannot completely rule it out as a distant possibility.

I am very sorry for your loss.