Guide to Paronychia: Exploring Its Causes, Recognizing the Symptoms, and Getting a Proper Diagnosis

Paronychia is an infection around the nail folds, the skin surrounding your fingernails and toenails. It manifests in two particular forms, namely, acute and chronic paronychia. In this article, the aim is to provide a comprehensive look and understanding of paronychia’s causes, symptoms, treatments, diagnosis and prevention.

What is Paronychia?

Paronychia is an infection affecting certain parts of the fingers and toes nails, including the areas near where the nail meets the skin (proximal) as well as the sides of the nail extending away from the body (lateral). This means it mainly affects the base and sides of the nails. This condition arises when the protective barrier between the nail and the nail fold is damaged, allowing bacteria, fungi, or viruses to enter the fold, causing inflammation and infection. It can spontaneously occur or from trauma or manipulation. In some cases, immunosuppressed or genetic predispositions make individuals susceptible to infection.

Paronychia is among the most common infections of the hand, but can also affect the toenails. Susceptibility to paronychia is caused by nail biting, sucking on fingers, manicures and in toes, infections usually begin with ingrown toenails. Other causes of infection include chronic irritation from constant exposure to water and detergents.

Paronychia is classified based on its clinical presentation and duration: acute, which is more common, and chronic, which is uncommon, and in rare cases, infections can be severe. Chronic infections also vary in their etiology, meaning could be a combination of or either bacterial, fungal, viral, or non-infectious pathogen. Individuals with pre-existing immunosuppressed conditions (HIV, diabetes) are also more susceptible to paronychia. Paronychia is more common in women than in men, with a female-to-male ratio of 3 to 11. Usually, they affect manual labor workers or patients in occupations that require them to have their hands or feet kept in water for prolonged periods (e.g., dishwashers).

Acute Paronychia

Acute paronychia develops rapidly, typically within a few days, and usually lasts less than six weeks. It primarily affects the fingernails and is usually caused by bacterial infections, most commonly Staphylococcus aureus. Acute paronychia is usually limited to one nail. It’s usually the result of trauma to the nail fold, such as a cut, hangnail, or ingrown nail, nail-biting, hand injuries and occupations involving harsh environments are often responsible for those who get acute paronychia.

Chronic paronychia develops gradually and persists for six weeks or longer. It can affect both fingernails and toenails and is often caused by a combination of factors, including fungal infections (especially Candida species), bacteria (Streptococci), and irritant exposure (overexposure to water and detergents). Less common causative agents include gram-negative organisms (such as pseudomonas), dermatophytes, herpes simplex virus, and yeast.

Chronic Paronychia

Chronic paronychia is more common in individuals with frequent exposure to water, such as dishwashers, bartenders, and housekeepers. Those who are at high risk of developing chronic paronychia depend on factors including occupation (dishwasher, bartender, housekeeper), certain medications, and immunosuppression (diabetes, HIV, malignancy).

Other Etiological Classifications

Bacterial paronychia is primarily caused by Staphylococcus aureus, a common bacterial pathogen responsible for skin infections. However, other bacteria such as Streptococci and Pseudomonas can also contribute, particularly in cases of chronic or recurring infections. This type of paronychia typically presents with localized redness, swelling, and pus formation around the nail fold. It often occurs due to trauma, nail biting, or exposure to moist environments, which encourage bacterial entry. Prompt treatment with antibiotics is usually effective, though chronic cases may require more targeted therapy to address resistant or atypical bacterial strains.

Viral paronychia, on the other hand, is most commonly associated with the herpes simplex virus (HSV), leading to a condition known as herpetic whitlow. Unlike bacterial paronychia, this form is characterized by painful vesicles or blisters around the nail bed, often accompanied by systemic symptoms like fever or malaise. It is also contagious and can spread from person to person.

Fungal paronychia, typically caused by Candida species, is more common in chronic cases and is often linked to prolonged exposure to water or irritants like detergents. Non-infectious paronychia can arise from external factors such as adverse reactions to medications

The symptoms of acute and chronic paronychia