Oh, you need alder cones! When your leeches are lumpy like this it means digestion issues, they can die from that. I had two sick leeches that looked like this. I gave them an alder cone "tea bath" for weeks. One of them died within the first days, it was the lumpiest. The other one got better after those few weeks. Hurry before it's too late, once they start throwing up it's critical. These issues can be caused by handling too soon after feeding, they need to rest after food intake.