Q. I am a patient in hospital. I am usually dressed in hospital issue clothing, which consists of a shirt and trousers, basically pajamas. I put my tzitzis on over my shirt in the daytime.
There is a shul in the hospital. If I was home, I would be horrified to be in shul in pajamas. May I enter the hospital shul in my hospital pajamas and daven, or is it better to daven in my room (without a minyan, etc.) It somehow seems to be a bizayon for the kedushah of the Beis HaKneses to be there in pajamas. And just because my body is sick, does my soul need to become desensitized to the need to show reverence for He Who dwells there?

A. Shulchan Aruch (98: 4) opines that one should don befitting and pleasant, dedicated clothing for engaging in tefila, similar to the use of special clothing by the Cohen when performing service at the Beis Hamikdash.
However when that requisite directly conflicts with the necessity to daven in a shul with a minyan, Horav Shlomo Miller Shlit”a maintains that the minyan and shul requirement preempts the clothing prerequisite. He recommended that the patient wear a befitting robe, akin to what people often use even for davening, commonly known as a house bekeshe or similar.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a