I treated a 20-year-old guy in clinic for finger pain. His index fingernail was split, and there was a lot of swelling and tenderness at the tip and at the nail cuticle.
The previous night he was lobster hunting from Lau Lau Beach by his family's house. The keys to lobster hunting, he replied to my insistence, are to go out after a light rain and to act quickly. He dives in at the reef and hopes to snatch the animals as they peer out from the rocks. If he can surprise them, the lobsters don't have time to grab onto the rocks. On the right night, he and his cousins can bring back 5-10 big lobsters. His uncle throws them into the pot and the family has a handsome boil.
That night, my patient was diving when he saw from his periphery a puffer fish angling for him. It bit his index finger.
Blood and pus can accumulate under a nail and cause problems. The nail needs to be removed to create a vent. One could argue that the split in this guy's nail acted like a vent, but I wanted to give him the VIP treatment. So I numbed the finger and pulled the nail off. With the nail removed, I saw that the split in the nail actually extended through the fleshy "nail bed" down to the bone. Three stitches approximated the edges.
Teeth--and thus bites--of different animals carry different bacteria. I have a guide that lists these and suggests appropriate antibiotics. I've used this guide before for dog, cat, human, and even horse bites. It was no help, though, for puffer fish.