Paronychia

Overview

Paronychia is an infection that develops in the skin around the nail, known as the nail fold. It's one of the most frequent infections encountered in hand surgery and dermatology practices. The condition affects people of all ages and can occur on both fingernails and toenails, though it's more common on fingers due to their frequent exposure to moisture and trauma.

There are two main types of paronychia: acute and chronic. Acute paronychia develops rapidly over hours to days and is usually caused by bacteria entering through a break in the skin. It's characterized by sudden onset of pain, swelling, and redness. Chronic paronychia develops slowly over weeks and is often related to repeated exposure to moisture and irritants, frequently involving fungal infections alongside bacterial colonization.

While paronychia can be painful and inconvenient, it's generally treatable with proper care. However, if left untreated, the infection can spread deeper into the finger or toe, potentially leading to more serious complications such as abscess formation or, rarely, osteomyelitis (bone infection). Early recognition and treatment are key to preventing these complications and ensuring quick recovery.

Symptoms

The symptoms of paronychia vary depending on whether the infection is acute or chronic, but both types share common features of inflammation and discomfort around the affected nail.

Acute Paronychia Symptoms

• Hand or finger pain - Throbbing pain that worsens with pressure
• Hand or finger swelling - Pronounced swelling around the nail fold
• Redness extending from the nail fold
• Warmth and tenderness to touch
• Pus-filled blister or abscess formation along the nail edge
• Difficulty using the affected finger due to pain
• Possible fever if infection is severe

Chronic Paronychia Symptoms

• Abnormal appearing skin - Thickened, boggy nail folds
• Persistent redness and swelling, less intense than acute form
• Cuticle loss or separation from the nail plate
• Nail plate changes including ridging, discoloration, or distortion
• Episodes of mild pain and tenderness
• Periodic drainage of small amounts of pus
• Multiple nails may be affected simultaneously

Location-Specific Symptoms

Finger Paronychia

• Skin on arm or hand looks infected - Red streaks may extend up the finger
• Hand or finger lump or mass - Abscess formation creating a visible bulge
• Difficulty with fine motor tasks
• Pain with gripping or grasping objects

Toe Paronychia

• Foot or toe pain - Especially when wearing shoes
• Foot or toe swelling - May make shoe-wearing difficult
• Skin on leg or foot looks infected - Spreading redness or streaking
• Difficulty walking comfortably
• Ingrown toenail may be present concurrently

Associated Symptoms

Some patients may experience additional symptoms, including:

• Sinus congestion - May occur with systemic infection
• Lymph node swelling in the armpit or groin
• General malaise or feeling unwell
• Joint stiffness in the affected digit

Causes

Paronychia results from the disruption of the protective barrier between the nail fold and nail plate, allowing microorganisms to enter and cause infection. The specific causes differ between acute and chronic forms.

Acute Paronychia Causes

Acute paronychia is typically caused by bacterial infection following trauma to the nail fold:

• Bacterial pathogens: Most commonly Staphylococcus aureus, including MRSA strains
• Streptococcus species: Group A beta-hemolytic streptococci
• Trauma sources:
  • Nail biting or picking at cuticles
  • Aggressive manicures or pedicures
  • Hangnails that are pulled or torn
  • Ingrown nails
  • Splinters or foreign bodies
  • Thumb sucking in children

Chronic Paronychia Causes

Chronic paronychia has a multifactorial etiology:

• Environmental factors:
  • Prolonged exposure to moisture
  • Frequent hand washing or wet work
  • Contact with irritants and chemicals
  • Cold, wet conditions
• Infectious agents:
  • Candida species (most common)
  • Mixed bacterial flora
  • Atypical mycobacteria (rare)
• Underlying conditions:
  • Eczema or dermatitis
  • Psoriasis affecting the nail unit
  • Diabetes mellitus
  • Immunosuppression

Contributing Mechanisms

Several mechanisms contribute to infection development:

• Barrier disruption: Loss of the cuticle seal allows entry of pathogens
• Moisture retention: Creates ideal environment for microbial growth
• Local inflammation: Irritant or allergic reactions weaken natural defenses
• Biofilm formation: Chronic cases may involve bacterial biofilms resistant to treatment
• Secondary infection: Initial irritation may become secondarily infected

Risk Factors

Various factors increase the likelihood of developing paronychia:

Behavioral Risk Factors

• Nail biting (onychophagia): Creates multiple entry points for bacteria
• Finger or thumb sucking: Especially in children, maintains moist environment
• Excessive cuticle manipulation: Picking, pushing, or cutting cuticles
• Poor nail hygiene: Allowing dirt and bacteria to accumulate
• Artificial nail use: Traps moisture and bacteria

Occupational Risk Factors

• Healthcare workers: Frequent handwashing and glove use
• Food handlers: Constant moisture exposure
• Dishwashers and cleaners: Exposure to water and detergents
• Bartenders: Wet conditions and citrus juice exposure
• Fishermen: Handling fish and constant moisture
• Hairdressers: Chemical exposure and wet conditions

Medical Risk Factors

• Diabetes: Impaired wound healing and increased infection risk
• Peripheral vascular disease: Poor circulation affects healing
• Immunosuppression: HIV, chemotherapy, or immunosuppressive medications
• Skin conditions: Eczema, psoriasis, or chronic dermatitis
• Medications: Retinoids, chemotherapy drugs affecting nail growth
• Nutritional deficiencies: Particularly protein and vitamin deficiencies

Environmental Risk Factors

• Living in humid climates
• Poor sanitation or hygiene facilities
• Shared nail care instruments
• Communal bathing areas
• Exposure to harsh chemicals without protection

Diagnosis

Diagnosis of paronychia is primarily clinical, based on physical examination and patient history. Laboratory tests may be needed in certain cases to guide treatment or identify causative organisms.

Clinical Evaluation

Healthcare providers assess several factors during examination:

• Visual inspection: Examining the nail fold for signs of infection
• Palpation: Checking for fluctuance indicating abscess formation
• Pain assessment: Determining severity and pattern of discomfort
• Duration of symptoms: Distinguishing acute from chronic paronychia
• Previous episodes: History of recurrent infections
• Occupational history: Exposure to moisture or irritants

Laboratory Tests

Culture and Sensitivity

• Bacterial culture from pus or drainage
• Fungal culture for chronic cases
• Antibiotic sensitivity testing for treatment guidance
• Particularly important for recurrent or treatment-resistant cases

Additional Tests

• Gram stain: Quick identification of bacterial type
• KOH preparation: To identify fungal elements
• Blood tests: If systemic infection suspected (CBC, blood cultures)
• X-ray: If osteomyelitis suspected in severe cases

Differential Diagnosis

Conditions that may mimic paronychia include:

• Herpetic whitlow: Viral infection with vesicles
• Felon: Deep space infection of fingertip pulp
• Mucous cyst: Clear fluid-filled lesion near nail
• Squamous cell carcinoma: Chronic non-healing lesion
• Melanoma: Pigmented lesion near nail
• Pyogenic granuloma: Vascular proliferative lesion

Treatment Options

Treatment approach depends on whether paronychia is acute or chronic, the severity of infection, and the presence of complications such as abscess formation.

Acute Paronychia Treatment

Conservative Management

For early, mild cases without abscess:

• Warm water soaks: 15-20 minutes, 3-4 times daily
• Antiseptic solutions: Povidone-iodine or chlorhexidine
• Topical antibiotics: Mupirocin or bacitracin ointment
• Oral antibiotics for moderate cases:
  • Cephalexin 500mg four times daily
  • Dicloxacillin 500mg four times daily
  • Amoxicillin-clavulanate for broader coverage
  • Trimethoprim-sulfamethoxazole for MRSA coverage

Surgical Intervention

Required for abscess formation:

• Incision and drainage: Under local anesthesia
• Partial nail removal: If infection extends under nail
• Marsupialization: For recurrent infections
• Daily dressing changes: Until healing occurs

Chronic Paronychia Treatment

Medical Management

• Avoid moisture and irritants: Essential for healing
• Topical corticosteroids: Reduce inflammation (betamethasone, clobetasol)
• Topical antifungals: Clotrimazole, ketoconazole, or ciclopirox
• Combination therapy: Steroid-antifungal preparations
• Tacrolimus ointment: For steroid-resistant cases
• Systemic antifungals: Fluconazole or itraconazole for severe cases

Protective Measures

• Cotton gloves under rubber gloves for wet work
• Barrier creams or petroleum jelly application
• Avoid harsh soaps and chemicals
• Keep hands dry between exposures

Surgical Options for Chronic Cases

• En bloc excision: Complete removal of affected nail fold
• Eponychial marsupialization: Creating permanent drainage
• Nail avulsion: Temporary or permanent nail removal
• Swiss roll technique: For recalcitrant cases

Adjunctive Treatments

• Pain management: NSAIDs or acetaminophen
• Hand therapy: For chronic cases with stiffness
• Nutritional support: Address deficiencies
• Treatment of underlying conditions: Diabetes control, eczema management

Prevention

Preventing paronychia involves protecting the nail folds from trauma and maintaining proper nail hygiene.

General Prevention Strategies

• Proper nail care:
  • Keep nails clean and trimmed straight across
  • Avoid cutting cuticles; gently push them back instead
  • Use clean, personal nail care tools
  • File rough edges to prevent catching and tearing
• Avoid nail trauma:
  • Stop nail biting and cuticle picking
  • Wear gloves for manual work
  • Be gentle during manicures and pedicures
  • Treat hangnails properly by cutting, not pulling

Moisture Protection

• Wear waterproof gloves for wet work
• Dry hands thoroughly after washing
• Apply moisturizer to prevent dry, cracked skin
• Change wet gloves and socks promptly
• Use cotton liner gloves under rubber gloves

Occupational Prevention

• Healthcare workers: Use alcohol-based sanitizers when possible
• Food handlers: Regular glove changes and hand drying
• Cleaners: Protective gloves and barrier creams
• Rotate tasks: Minimize continuous wet exposure

For High-Risk Individuals

• Diabetics: Daily foot and nail inspection
• Immunocompromised: Extra vigilance with nail care
• Those with skin conditions: Manage underlying condition
• Previous paronychia: Prophylactic measures and early treatment

When to See a Doctor

While mild paronychia may resolve with home care, certain situations require medical evaluation to prevent complications.

Seek Immediate Medical Care For:

• Signs of spreading infection (red streaks extending from the site)
• Fever, chills, or feeling generally unwell
• Severe hand or finger pain not relieved by over-the-counter medications
• Rapidly worsening hand or finger swelling
• Pus accumulation under the nail or in surrounding tissue
• If you have diabetes or are immunocompromised
• Joint stiffness or inability to bend the finger

Schedule an Appointment If:

• Symptoms persist after 2-3 days of home treatment
• Skin on arm or hand looks infected despite initial care
• Recurrent episodes of paronychia
• Chronic symptoms lasting more than 6 weeks
• Nail changes such as discoloration or separation
• Multiple nails are affected
• Abnormal appearing skin that doesn't improve

Emergency Situations

Go to the emergency room if you experience:

• Severe infection with systemic symptoms
• Suspected blood poisoning (sepsis)
• Extreme pain suggesting deep space infection
• Numbness or tingling in the affected digit
• Blue or gray discoloration of the finger

Related Conditions

Several conditions may occur alongside or be confused with paronychia:

• Herpetic Whitlow - Viral infection of the finger
• Felon - Deep infection of the fingertip pulp
• Ingrown Nail - Often coexists with paronychia
• Cellulitis - Can develop from untreated paronychia
• Onychomycosis - Fungal nail infection
• Psoriasis - Can affect nails and mimic chronic paronychia
• Eczema - May predispose to paronychia
• Nail Trauma - Common precipitating factor