Differential Diagnosis for 66-year-old Female with Pus Pocket and Redness on Finger
- Single most likely diagnosis:
- Paronychia: This is the most likely diagnosis given the patient's history of trauma to the cuticle region, followed by the development of a pus pocket, redness, swelling, and discomfort. The patient's attempt to drain the pus pocket with a safety pin and subsequent expression of discharge are common presentations of paronychia.
- Other Likely diagnoses:
- Felon: A felon is an infection of the fingertip pulp and could be considered given the patient's symptoms of redness, swelling, and discomfort. However, the initial location of the pus pocket near the cuticle region makes paronychia more likely.
- Herpetic whitlow: This is a viral infection of the finger caused by herpes simplex virus and could present with similar symptoms. However, the absence of vesicles or a history of herpes infection makes this less likely.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- Osteomyelitis: Although less likely, osteomyelitis (an infection of the bone) could occur, especially given the patient's history of arthritis, which may increase her risk for infections. Missing this diagnosis could lead to serious complications, including bone destruction and sepsis.
- Septic arthritis: Given the patient's history of arthritis, there is a possibility of septic arthritis, especially if the infection spreads to the joint. This is a medical emergency that requires prompt treatment to prevent joint destruction and other complications.
- Rare diagnoses:
- Erysipelas: A type of bacterial infection of the upper layer of the skin that could present with redness and swelling. However, it typically involves the face or lower extremities and is less common on the fingers.
- Pyogenic granuloma: A benign vascular tumor that can appear as a red, bleeding bump, often after trauma. While possible, the patient's symptoms of pus and increasing redness and swelling over time make this less likely.