Gentamycin and deafness?

Hope you can help with my question. I have a 11 year old cat named Emma, that has been having upper respiratory problems for the past 3-4 years. She would have discharge from her nose that would dry and plug up the end. Sometimes there would be a reddish tinge of blood to it. She would sneeze and fling her head and this stuff would fly all over. She also had some crusty discharge around her eyes that we kept wiping away. Three to four times a day, maybe more, she would cough with a wheezy sound for 3-4 minutes at a time, almost like a spasm. The first vet we took her to did some type of nose swab. I‘m not sure of the results of this but she put her on Amoxicillin liquid and also Prednisone. This seemed to help her but every time we stopped the medication she got worse again. We also tried Cipro, but I think the Amoxicillin helped her more. We were using the Amoxicillin, Prednisone, and Methprednisoline in various combinations, but she was not really getting better. In October of 2012 we switched vets. After an examination of Emma ,he said she maybe what he termed a “ chronic snuffler”.The vet suggested doing a nasal flush and the results would give them a better idea of what is causing this problem and how to best treat it. He said if you don’t do this testing, then Its hit or miss on what type of antibiotic to use. But first he suggested trying her on Doxycycline for 1-2 months. You could see an improvement within 2-3 days and she got better the longer she was on it. The vet also added Zeniquin and that seemed to help even more. There hasn’t been any heavy discharge from her nose and these coughing/wheezing spells have almost stopped. She’s been on the two antibiotics since October( ~$32.00 for 2 weeks worth), But there is still some congestion and a gurgling sound when she breaths. She still sneezes to try to clear her nose and gulps every so often like she has a sore throat. I would say that she is 70-75 % improved when she is on these 2 antibiotics. We stopped these antibiotics about 2 weeks ago to see what would happen, and she seemed to get worse again almost within 2-3 days of not being on them. Last Thursday we took her in and had the nasal flush, a fluid evaluation, and blood work done. The results of the blood work was fine, all within normal ranges ,lungs, kidney,and heart ok also. What they found when they cultured the nasal flush was Pseudomonas Aer infection. He said the culture showed a reasonable amount(level4) of this present. His suggesting using injectable Gentamycin (small dose, I think 0.1 cc for 10 days). BUT he said a bad side effect could occur—permanent deafness. I’m really worried about this. According to the lab report he was given, oral antibiotics would have no effect on this bacteria type. The lab report suggested 3-4 different injectable antibiotics to try. He said that the Genomycin would be the one to try because it would require 1 injection per day and the others would require injections every 8 hours. But that still won’t guarantee it will completely get rid of It on the first try, and the longer you use this, you increase the chance to this deafness occurring. Are there any other safer options available? Emma is much improved when she’s on the Zeniquin & Doxycycline, but the vet said these 2 antibiotics have no effect on this type of bacteria. He does not seem to know why she seems better when she’s on these. Is it worth the risk to use this Gentamycin to treat this bacteria, knowing permanent hearing loss could result? Do you have any experience using this medication? Are there any studies showing the % of risk of deafness that occurred when using this medication? Would keeping her on a maintenance dose of antibiotic and not treating the bacteria be better? Would you suggest another antibiotic to try? Could the cat be worst off being deaf (balance problems etc.) than it is with its current problems? I know I have asked a lot of questions. I hope you can answer some of them. We would do almost anything to help Emma.

DR. Marie

Thank you for your timely answer to all of my questions.I talked to our vet again on Friday asking him if he has used this injectable Gentamycin and had ever had a cat go deaf. He said he has used it many times and had no problems with the deafness issuses.He thought that while deafness could occur it would be a rare occurance and unlikely using this low dose.You said you thought deafness would also be rare using the gentamycin,which goes along with his line of thinking also.
Your response to my questions has helped us decide to treat Emma with the Gentomycin and not worry about the deafness issuses.I will also ask the vet about the Mycoplasma fells you mentioned.

Thank you,