13 yr old kitty problem

Our 13 yr old male neutered kitty Screech has, for probably 6 months now, had a lump growing on the back of his neck.  We were going to take him to see the vet but they moved out of town so we have been looking for another.  He has lost about 8 lbs. during this time but, otherwise, seems to feel good.  He used to weigh around 26 lbs.  Eats and drinks but his poop is runny.  Used to be hard as a rock.  This morning, the lump opened on its own and black runny liquid came out that smelled like methiolate.  Hope you know what that smells like. Scared the heck out of me.  I have never smelled anything like that before.  Has anyone else had this happen or know what this is?  Could it just be decomposed puss?  We are planning to get him to a vet as soon as we can.  Thanks.

I don't know what could be happening. I am glad you are going to get him to a vet ASAP. Many vibes that he recovers soon.

The lump is one thing, but I have never heard of the sight and smell you described. This sounds serious. He could have a really bad infection. Please get Screech to the vet ASAP.

Thanks.

Thanks.  I googled this the best I could and found that someone else had an issue somewhat like this with a kitty and they said it was a sebaceous cyst.  Even the black liquid coming from it.  The vet said to clean it with peroxide and apply some antibiotic creme.  I will do that until I can get him to the vet.  His weight loss and diarrhea worries me also.  Thanks again.

Yes, that's a huge weight loss for only 6 months time. And, of course, diarrhea is not normal.  What is he eating?

Did he let you clean the wound  up and apply the cream?  How's it looking now?

Thanks for all your help.  The lump opened on its own and I have put peroxide and an antibiotic on it.  It seems to be better and the diarrhea is lessening.  His poop is becoming firmer.  We are back to giving him meds to soften it again.  There is still the weight problem and we are going to address that as soon as we can.  He just wants to sit on my lap and sleep a lot.  I feel there is a problem and we`ll get it taken care of.  Thanks again.  Great site.

Happy to hear that the wound is healing and his bowel movements seem to be returning to normal. With the weight loss I would definitly recommend having him seen by a vet. There are several things that could be causing the weight loss. I would recommend asking your vet to run senior blood panels to check and make sure that his thyroid is functioning properly and also to check that his kidneys are functioning properly also.