It would be essential to rule out osteomyelitis/infective bone disease as also a incipient brain abscess by doing imaging studies like a CT/MRI scan.A culture and sensitivity test for the discharge will help select the best antibiotics ,this is a emergency especially since he has a compromised immune system.His treating doctor and physician should decide whether the drugs weakening the immune system can be stopped till the infection is completely controlled.

Hello,

Thanks for posting on HCM,

The fact that your husband is on methotrexate and enbrel ( etanercept) which are two medications that seriously interfere with system's immunity and may pose or will pose great issues with your husband's ability to fight infections. Now your treating doctor needs to be very smart with his decision as in one side he needs to treat your psoriatic arthritis and in the other side he needs to treat your MRSA. MRSA could result in very serious complications given it ENT location notably encephlitis and/or meningitis (immunodepression + ENT infection can always result to infection of the brain tissues). If this occurs, then your husband will be faced with a more troublesome situation.
My suggestion is that, your husband's psoriatic arthritis needs to be reevaluated and maybe he should just be maintained as of now only with NSAID to deal with the inflammation and provide with immune boosting medications (if any available at your context). Some few antibiotics can handle the MRSA but at this point, it is better a sample of the fluid discharge from his ear to be analyzed in the laboratory for antibiotics sensitivity so that specific antibiotics can be given both orally and locally (oral or IV or IM route will be best indicated in this situation for proper systemic circulation). So saying methotrexate and enbrel could be withheld for a while until the infection is completely eradicated then be placed again on same or different medications if psoriatic arthritis persist.

Hope this helps