Lung inflammation

Hello, I took my 6 year old indoor male cat for a blood test, heart scan and x-rays of his airways. His heart is healthy, blood tests came back normal, but x-rays showed inflamed lungs. His vet said it isn’t asthma, cancer or lungworm, but mentioned an allergic response. I asked whether there was any lung damage / scarring and he said he didn’t think so at this stage but that he couldn’t say for sure. My cat’s symptoms for the past five months have been exaggerated swallowing motions (most noticeable when he purrs), and a slight gulping sound every time he swallows. Also started dribbling when he purrs. Coughing every week or so. The coughing often happens about 15 minutes after eating. He also had a mini sneezing fit recently. He regurgitated four flakes of food three hours after eating recently, but he’s never sick. During the heatwaves and after vet visits in the past month or so he has had episodes of panting and breathing extremely fast. Over the past few weeks he’s been breathing quite fast on and off, which seems to usually be worse in late evenings, sometimes 50 breaths per minute. He has quite a lot of plaque on his teeth and is obese, at 7.6kg. For the past couple of months he’s been sleeping all day, less interested in food than he was, and not himself, which I had put down to the heat at first, but it hasn’t improved. Any information would be so appreciated. I’m so worried about him and don’t know what lung inflammation means, what the cause of this is and whether he can make a full recovery. Thanks so much for any help!

Hello and thankyou for this fascinating question.  In answering it, please remember that I have neither reviewed the radiographs nor examined your cat, so despite the excellent descriptions that you have provided, I have infinitely less information available to me than your vet does.  First of all, 'lungs' are a big area.  They usually appear relatively black on radiographs (because they are full of air) with the heart (white - soft tissue) silhouetted over them and some typical 'textured' patterning reflecting the lung lobes, alveoli and so on.  You can probably find 'normal' radiographs to look at.  An excessively white area or 'an increased area of soft tissue density' can represent many things, one of which is inflammation i.e. a large number of white blood cells having moved into that area.  This could include allergy, an inflammatory response to a foreign body, a reaction to parasites, the effects of fungi, viral or bacterial disease.  However it might also represent blood, abscesses, tumours (unusual at this age), fluid e.g. secondary to heart disease, or even abnormal lung formation or the presence of abdominal organs in the wrong place (diaphragmatic hernia).  Pneumonia simply means inflammation of the lungs.  There are many different kinds of pneumonia and the presentation (the vets' findings on listening to the chest) and signalment (age, breed, lifetyle etc of the patient) as well as the positioning within the lung fields, can help the vet to narrow it down to several most likely differentials (possible causes).  They may need to do further tests.  In this case, you also describe signs that sound like regurgitation or vomiting - often, cats retch and regurgitate (and even eat what they vomit if it comes up), so vomit isn't always seen.  When cats vomit, they sometimes aspirate (breathe in the vomit) which has typical lung patterns associated with it but can take on a variety of appearances on radiography.  Aspiration can be seen after ingesting foreign bodies or with diseases such as pancreatitis or mega-oesophagus, which is where the food-pipe appears abnormally large and food tends to come back up the throat. It sounds as if your vet has two jobs to do: 1) work out exactly what is causing this pattern of 'inflammation' in your cats' case and 2) work out how best to look after your cat in the meantime, because they sound not to be breathing on full capacity and this is serious.  Oxygen, drugs or other treatment may help to some extent. How do things stand now?   Wishing you both all the very best.  

It sounds as if your vet is monitoring this case and is happy that your cat is stable but if this is not the case - certainly if breathing has deteriorated since your vet saw then at any time, always treat it as an emergency and please notify them.

Thank you so much for your response. He has been prescribed budesonide tablets and I’ve given them to him for a week so far, but I haven’t noticed any improvement in his symptoms yet. His x-rays showed a mild bronchial pattern, but I’m unsure what this means.

A bronchial pattern is increased visibility of the bronchial walls (the branches of certain passage-ways leading into the lungs) on the x-ray, usually because of inflammation, increased fluid or infection.  It is a vague sign, in that it can reflect a number of different disease processes.  I don't know of licensed uses of Budesonide that would fit this case and frustratingly from here, I am unable to understand what diagnosis has been given to your cat.  However, I would expect your vet to have a rationale.  As things don't appear to have improved and breathing is involved, a re-triage (assessment of the urgency regarding timing of a consultation) may to be required.  How far through their 'work-up' are your vets?  For example, they might be wanting to rule out certain parasites, infections, exposure to chronic irritants, increased mucous..... any of which might present with a bronchial pattern.

His vet suggested maybe carrying out a bronchoscopy, but I am worried about the risks. Lungworm has been ruled out, along with asthma. Some possible causes mentioned were allergies, foreign body and mucus plug. I believe the inflammation is localised. He is currently halfway through a 14 day course of doxycycline, as well as still taking the 1mg budesonide tablets once per day, but so far his symptoms haven’t improved in the 3 or so weeks since treatment began. He was exposed to smoke with his previous owner, and has always been an indoor cat, but he didn’t start showing symptoms until 7 months after I got him. Nobody has smoked around him in the past year since I got him. He never had rapid breathing episodes until the heatwaves began from the end of June. It was extremely hot in my flat at times during the heatwaves. Ever since then, he has become lethargic and now breathes rapidly after any light activity, such as grooming or playing with his toys for only a few seconds, or sometimes the rapid breathing seems to happen for no apparent reason, often in the late evenings. He did have a mild occasional cough and was gulping whenever he swallowed in the months before the rapid breathing episodes started. I’m worried the ongoing inflammation could cause permanent airway damage and am not sure where to go from here. Could a CT scan be helpful in ruling out some of the possible causes? Are there any other treatments or tests to try? Is this something he may be able to recover from? Many thanks!