Can it be MALS? Advice needed

I am 41M and I have been suffering from upper abdomen pain for 13 years now. The pain is constant but its intensity varies. Stress usually makes it worse. My stomach is often swollen and painful to the touch. The pain is not acute and usually I am able to function more or less normally but the quality of life is not great. It is weakly correlated with food, I was never able to discover any pattern. I visited many gastroenterologist over the years and after doing extensive diagnostic they all eventually conclude that its IBS (of course). However, no treatment ever worked and I was treated with anti-depressants, painkillers, antibiotics, and many IBS related drugs. I also have neither constipation nor diarrhea. In addition to pain, I also find it very difficult to maintain body mass. I currently weight 58 kg and my height is around 6 feet. Two years ago I hit my lowest weight ever and it was 53 kg but I was able to very slowly recover from that. In addition to upper abdominal paint, I suffer from painful joints but the intensity is rather low and I have no swelling and no rheumatic disease was ever diagnosed.

Please let me know if this rings a bell for anyone. Can it be MALS? Does anyone experience similar symptoms?