A 22 year old woman has a tender finger one day after moving boxes in a garage. She states that while moving boxes, “the edge of one of the boxes struck and pushed the edge of my skin where it meets the nail very hard. It hurt for about 15 minutes and then went away. The next day when I woke up it was very painful and looked like this.” (She texted in a picture with her smart phone).
She was otherwise healthy and only taking a multivitamin and OCP's.
What is your diagnosis?
Paronychia is inflammation of the skin around a nail. Paronychia is usually characterized as either "acute Paronychia", or "chronic Paronychia". More often than not, it affects the nails on the hands, but can also affect the nails on the feet. Both types of Paronychia usually involve infections. The acute Paronychia is exquisitely tender and often caused by bacteria that are introduced secondary to trauma, as in this case where the corner of a moving box injured the nail fold. Other common causes of trauma include aggressive manicures, nail biting, hang nail removal, ingrown nails, splinters/foreign bodies, and any extended use of hands where nail fold trauma is a high probability. Chronic Paronychia that involves inflammation and redness around the fingernail and lasting more than 4-6 weeks is typically not painful and is often caused by fungus.
I find the most instructive investigation to use when a patient presents with Paronychia is to ask them if it hurts or not.
In regards to acute Paronychia, and although there is not strong supporting clinical research, in my experience an antibiotic usually works well and solves the problem. In this particular case the patient was given a Z-pack, and reported completed improvement in two days. Cephalexin and Clindamycin are reported to work well, too. For chronic Paronychia, often an oral anti-fungal medication is used in conjunction with a mild-moderate topical anti-inflammatory steroid (such as triancinalone ointment 0.1%), BID x 5-7 days. Although there are many oral anti-fungal options my treatment of choice is either Terbinafine (Lamisil) 250 mg once daily for 30 days, or a one week pulse of Itraconazole (Sporanox, 200 mg tabs, ii PO BID x 7 days). For Terbinafine, I do baseline CBC and LFT's and repeat in 7-10 days.
In cases of acute Paronychia where there is a pustule, the pustule should be drained before initiating antibiotic therapy, and warm water soaks should also be instituted daily for the first few days.