Usually result from minor trauma of the skin around the fingernail such as biting, manicures, picking a hangnail or finger sucking.
Staphylococcus aureus is the most common infecting organism. However other mouth flora such as Streptococcus and Pseudomonas species, gram-negative bacteria, and anaerobic bacteria can also be a cause.
Recommended treatement consists of incision and drainage and placing the patient on amoxicillin / clavulanic acid or clindamycin to cover all the organisms noted above.