History
The patient's history is crucial in determining the possibility of systemic conditions and risk factors that may predispose an individual to paronychia. [15, 20, 21, 22, 23, 24] These may include the following:
-
Diabetes mellitus [25]
-
Obesity
-
Hyperhidrosis
-
Immunologic defects
-
Polyendocrinopathy
-
Drug-induced immunosuppression
Patients may give a history of the following [9, 28] :
-
Nail biting
-
Finger sucking
-
Trivial finger trauma
-
Finger exposure to chemical irritants
-
Use of acrylic nails or nail glue
-
Sculpted nails
-
Frequent hand immersion in water
Also query patients about the duration of symptoms and a history of nail infections and previous treatment.
Because paronychia has been known to initiate from malignant lesions, any history of prior malignancy or a pigmented, irregular appearance of surrounding tissue should result in appropriate suspicion and referral for biopsy.
Painless swelling or severe swelling that radiates requires an expanded differential diagnosis. [29] Painless swelling lateral to the nail plate in a patient with osteoarthritis should prompt investigation for a mucous cyst.
Acute paronychia
The patient is usually otherwise healthy but complains of pain, tenderness, and swelling in one of the lateral folds of the nail.
Chronic paronychia
Generally, patients report symptoms lasting 6 weeks or longer. Inflammation, pain, and swelling may occur episodically, often after an exposure to water or a moist environment.
Chronic and recurrent paronychial infections should be scrutinized to rule out malignancy or fungal infection. [30, 31, 32]
Physical Examination
Acute paronychia
Physical findings in acute paronychia include the following:
-
The affected area often appears erythematous and swollen
-
In more advanced cases, pus may collect under the skin of the lateral fold
-
If untreated, the infection can extend into the eponychium, in which case it is called eponychia
-
Further extension of the infection can lead to the involvement of both lateral folds as it tracks under the nail sulcus; this progression is called a runaround infection
In severe cases, the infection may track proximally under the skin of the finger and volarly to produce a concomitant felon. The fulminant purulence of the nail bed may generate enough pressure to lift the nail off the nail bed.
Chronic paronychia
Physical findings in chronic paronychia include the following:
-
Swollen, erythematous, and tender nail folds without fluctuance are characteristic of chronic paronychia
-
Eventually, the nail plates become thickened and discolored, with pronounced transverse ridges
-
The cuticles and nail folds may separate from the nail plate, forming a space for the invasion of various microorganisms
Additional considerations
Other signs to look for in a physical examination include the following:
-
Look for signs of a herpetic whitlow, such as vesicles on an erythematous base
-
Green coloration of the nail may suggest Pseudomonas species infection
-
Hypertrophy of the nail plate may be a clue to fungal infection
-
Constant severe pain with nail plate elevation, bluish discoloration of the nail plate, and blurring of the lunula suggest the presence of a glomus tumor.
The digital pressure test can be used to detect the presence of an abscess. Pressure is applied to the palmar surface of the distal finger; if an abscess is present, the area of the abscess will blanch with palmar pressure. [33]
-
Classic presentation of paronychia, with erythema and pus surrounding the nail bed. In this case, the paronychia was due to infection after a hangnail was removed.
-
In this case of paronychia, no pus or fluctuance is involved in the nail bed itself.
-
Typical appearance of paronychia.
-
Depicted are the nail fold (A), dorsal roof (B), ventral floor (C), nail wall (D), perionychium (E), lunula (F), nail bed (G), germinal matrix (H), sterile matrix (I), nail plate (J), hyponychium (K), distal groove (L), fascial septa (M), fat pad (N), distal interphalangeal joint (O), and extensor tendon insertion (P).
-
Simple acute paronychia can be drained by elevating the eponychial fold from the nail with a small blunt instrument such as a metal probe or elevator.
-
Paronychia incision and drainage.
-
Paronychial erythema and edema with associated pustule. This suggests a bacterial etiology.
-
Paronychia, side view.
-
After simple drainage, there is purulent return.
-
Wound opened with a small incision using a No. 11 blade scalpel.
-
The wound can be explored with a blunt probe, clamps, or the blunt end of a cotton swab.
-
Ensure that all loculations are broken up and that as much pus as possible is evacuated.
-
Prior to packing or dressing the wound, irrigate the wound with normal saline under pressure, using a splash guard, eye protection, or both.
-
The wound can be covered with antibiotic ointment or petroleum jelly to prevent bandage adhesion.
