Paronychia

 

Primary Care Visit Report   

A 32-year-old male with no past medical history presented with swelling of his right hand fourth finger, near his fingernail. It started the day prior to this visit, and he said he felt a lot of pressure in the fingertip. He tried icing it overnight with no improvement. 

Vitals were normal. On exam, the skin lateral to the fingernail on his right hand fourth finger was  erythematous, edematous, warm, and very tender to palpation. There was minimal fluctuance. 

This was treated as paronychia. His finger was first soaked in warm water for 30 min, then an incision and  drainage  procedure was performed with a digital nerve block. However, no pus was expressed. The patient was sent home with instructions to soak his finger in warm water twice daily and to apply bacitracin to the area. He was asked to return to the office if the redness and swelling persisted or worsened.  

Discussion from Dermatology Clinic 

Differential Dx   

•   Bacterial paronychia  

•   Candidal paronychia  

•   Drug-induced paronychia  

•   Nail fold dermatitis  

•   Herpetic whitlow  

•   Ingrown nail     

Favored Dx   

Clinical examination and history are consistent with acute bacterial paronychia. It is apparent from physical examination that the patient is a nail biter, which is one of the predisposing factors for paronychia.  

Overview   

Paronychia is a common infl ammation of the proximal nail fold and  periungual soft tissues  , which is classifi ed as acute when it lasts fewer than 6 weeks, and chronic when it lasts greater than 6 weeks. The majority of cases are acute paronychia, which is most commonly associated with bacterial infection following mild local trauma, while chronic paronychia is associated with candidiasis. Predisposing factors for paronychia are exposure to chemical irritants, mechanical factors such as nail biting, picking, or fi nger sucking, and systemic conditions, such as diabetes and HIV [ 1 ,  2 ]. Less frequently, paronychia has been associated with use of certain medications, such as protease inhibitors, antiretrovirals, and chemotherapeutic agents. 

The most common bacterial pathogen involved in acute paronychia is  Staphylococcus aureus   .   Streptococcus pyogenes   ,   Pseudomonas aeruginosa   , and   Proteus  species   are involved with less frequency [ 1 – 3 ]. Most cases of bacterial paro-nychia are caused by mixed fl ora, and paronychia that comes in contact with oral fl ora, as in nail biting and fi nger sucking, typically involves anaerobic bacteria [ 2 ,  4 ].   Candida albicans    is often found in chronic paronychia. The pathogenesis of chronic paronychia is usually complex and multifactorial, and is currently thought to be an infl ammatory process which may feature an overlying acute (i.e., bacterial) paro-nychia.  Chronic    paronychia   is associated with excessive moisture, which may be the result of frequent immersion of the hands in water, as happens with occupational wet work. Paronychial herpes simplex virus lesions are referred to as herpetic whitlow.  

Presentation   

Acute  paronychia   presents as rapid-onset periungual erythema, swelling, and ten-derness.  Acute paronychia   may develop within hours, and there may be ulceration and purulence. It usually presents on a solitary digit [ 2 ]. 

Chronic  paronychia      can lead to changes in the nails, such as thickening, ridging, and discoloration [ 1 ]. Chronic paronychia is not usually purulent, and it may be long-standing. More than one fi ngernail is often involved.  

Workup   

 Physical examination and history are usually suffi cient to make a diagnosis. A bac-terial or fungal culture of contents expressed from the wound may be performed to confi rm the offending pathogen; however, it is often not necessary.  

Treatment   

 Treatment approach depends on whether the paronychia is acute or chronic, and the severity of infl ammation. Acute bacterial  paronychia      may be treated with  warm water compresses  , and topical or oral antibiotics. Warm water compresses for 20 min up to three times a day may be suffi cient treatment for mild cases of acute paronychia with minimal infl ammation and no abscess. Their main role in treatment of severe cases is as adjunct therapy [ 1 ,  2 ]. Topical antibiotics such as  mupirocin   can be added to cases with more severe erythema, applied after each warm compress or soak. Oral antibiotics are appropriate for severe cases with severe infl ammation [ 1 ]. For patients not exposed to oral fl ora (no nail biting and/or a paronychia of a toe), coverage of skin fl ora alone is appropriate—such as cephalexin 500 mg three or four times daily or dicloxacillin 250 mg four times daily. If oral fl ora exposure is present, amoxicillin/clavulanate 875/125 twice a day is appropriate. MRSA should be  covered by the chosen antibiotic where there is a signifi cant community  MRSA   presence [ 3 ,  4 ]. Clindamycin is a good option for MRSA coverage. 

Alternately, although there is no evidence to the authors’ knowledge of I&D having better or worse outcomes than oral antibiotics alone [ 2 ,  5 ], clinically it is com-mon practice to perform an  incision and drainage (I&D)   on acute paronychia with an abscess. After appropriate local anesthesia (i.e., a digital block), a scalpel inci-sion in the affected cuticle margin can relieve pressure and allow the patient some immediate symptomatic relief. Often incision and  drainage   can be suffi cient to treat paronychia with abscess or oral antibiotics can be added after the I&D along with warm soaks which would help ensure the abscess would continue to drain. Oral antibiotics are typically prescribed for a 5 day course if an I&D is performed, or a 7–10 day course without I&D. Cases with nail irregularities can be referred to a dermatologist or hand surgeon. 

 Chronic  paronychia     , thought to be caused by prolonged exposure (often occupa-tional) to water, features   Candida albicans    in up to 95 % of cases [ 1 ]. The role of  C. albicans  in prolonging paronychia is unknown, and chronic paronychia is con-sidered an infl ammatory disorder. This variant may be treated with topical or oral (in severe cases)  antifungals   such as itraconazole and fl uconazole; however, there is greater improvement when potent topical corticosteroids are used instead [ 6 ,  7 ]. A 2-week course of a potent topical  steroid   (Class I or II) is recommended for chronic paronychia. Additionally protective measures, such as wearing gloves, should be used in order to keep hands dry and away from irritants or allergens. If these treatments do not resolve the chronic paronychia, a course of antifungal ther-apy can then be added. Since chronic paronychia is now considered to be an eczem-atous process, it is equally important to address any underlying factors contributing to pathogenesis, including keeping hands dry in cases where excessive moisture is a causative factor, or treating systemic illness such as diabetes or HIV.

     Follow-Up   

 Patients should be reevaluated after 1–2 weeks of treatment. Clinical improvement rather than cure may be the outcome for chronic paronychia. Avoiding environmen-tal irritants, picking and biting habits, or other known triggers are essential in achieving a long-term cure. Recalcitrant cases should be referred to dermatology or hand surgery.   

while chronic paronychia is associated with candidiasis. Predisposing factors for paronychia are exposure to chemical irritants, mechanical factors such as nail biting, picking, or fi nger sucking, and systemic conditions, such as diabetes and HIV [ 1 ,  2 ]. Less frequently, paronychia has been associated with use of certain medications, such as protease inhibitors, antiretrovirals, and chemotherapeutic agents. 

 The most common bacterial pathogen involved in acute paronychia is   Staphylococcus aureus   .   Streptococcus pyogenes   ,   Pseudomonas aeruginosa   , and   Proteus  species   are involved with less frequency [ 1 – 3 ]. Most cases of bacterial paro-nychia are caused by mixed fl ora, and paronychia that comes in contact with oral fl ora, as in nail biting and fi nger sucking, typically involves anaerobic bacteria [ 2 ,  4 ].   Candida albicans    is often found in chronic paronychia. The pathogenesis of chronic paronychia is usually complex and multifactorial, and is currently thought to be an infl ammatory process which may feature an overlying acute (i.e., bacterial) paro-nychia.  Chronic    paronychia   is associated with excessive moisture, which may be the result of frequent immersion of the hands in water, as happens with occupational wet work. Paronychial herpes simplex virus lesions are referred to as herpetic whitlow.  

     Presentation   

 Acute  paronychia   presents as rapid-onset periungual erythema, swelling, and ten-derness.  Acute paronychia   may develop within hours, and there may be ulceration and purulence. It usually presents on a solitary digit [ 2 ]. 

 Chronic  paronychia      can lead to changes in the nails, such as thickening, ridging, and discoloration [ 1 ]. Chronic paronychia is not usually purulent, and it may be long-standing. More than one fi ngernail is often involved.  

     Workup   

 Physical examination and history are usually suffi cient to make a diagnosis. A bac-terial or fungal culture of contents expressed from the wound may be performed to confi rm the offending pathogen; however, it is often not necessary.  

     Treatment   

 Treatment approach depends on whether the paronychia is acute or chronic, and the severity of infl ammation. Acute bacterial  paronychia      may be treated with  warm water compresses  , and topical or oral antibiotics. Warm water compresses for 20 min up to three times a day may be suffi cient treatment for mild cases of acute paronychia with minimal infl ammation and no abscess. Their main role in treatment 

of severe cases is as adjunct therapy [ 1 ,  2 ]. Topical antibiotics such as  mupirocin   can be added to cases with more severe erythema, applied after each warm compress or soak. Oral antibiotics are appropriate for severe cases with severe infl ammation [ 1 ]. For patients not exposed to oral fl ora (no nail biting and/or a paronychia of a toe), coverage of skin fl ora alone is appropriate—such as cephalexin 500 mg three or four times daily or dicloxacillin 250 mg four times daily. If oral fl ora exposure is present, amoxicillin/clavulanate 875/125 twice a day is appropriate. MRSA should be  covered by the chosen antibiotic where there is a signifi cant community  MRSA   presence [ 3 ,  4 ]. Clindamycin is a good option for MRSA coverage. 

 Alternately, although there is no evidence to the authors’ knowledge of I&D hav-ing better or worse outcomes than oral antibiotics alone [ 2 ,  5 ], clinically it is com-mon practice to perform an  incision and drainage (I&D)   on acute paronychia with an abscess. After appropriate local anesthesia (i.e., a digital block), a scalpel inci-sion in the affected cuticle margin can relieve pressure and allow the patient some immediate symptomatic relief. Often incision and  drainage   can be suffi cient to treat paronychia with abscess or oral antibiotics can be added after the I&D along with warm soaks which would help ensure the abscess would continue to drain. Oral antibiotics are typically prescribed for a 5 day course if an I&D is performed, or a 7–10 day course without I&D. Cases with nail irregularities can be referred to a dermatologist or hand surgeon. 

 Chronic  paronychia     , thought to be caused by prolonged exposure (often occupa-tional) to water, features   Candida albicans    in up to 95 % of cases [ 1 ]. The role of  C. albicans  in prolonging paronychia is unknown, and chronic paronychia is con-sidered an infl ammatory disorder. This variant may be treated with topical or oral (in severe cases)  antifungals   such as itraconazole and fl uconazole; however, there is greater improvement when potent topical corticosteroids are used instead [ 6 ,  7 ]. A 2-week course of a potent topical  steroid   (Class I or II) is recommended for chronic paronychia. Additionally protective measures, such as wearing gloves, should be used in order to keep hands dry and away from irritants or allergens. If these treatments do not resolve the chronic paronychia, a course of antifungal ther-apy can then be added. Since chronic paronychia is now considered to be an eczem-atous process, it is equally important to address any underlying factors contributing to pathogenesis, including keeping hands dry in cases where excessive moisture is a causative factor, or treating systemic illness such as diabetes or HIV.

     Follow-Up   

 Patients should be reevaluated after 1–2 weeks of treatment. Clinical improvement rather than cure may be the outcome for chronic paronychia. Avoiding environmental irritants, picking and biting habits, or other known triggers are essential in achieving a long-term cure. Recalcitrant cases should be referred to dermatology or hand surgery.   

    Questions for the Dermatologist 

–  What conditions lead to paronychia? Is nailbiting a factor?  

 There are two forms of paronychia:  acute      and  chronic     .  Nail biting   can predispose someone to either form by exposing the nail fold to pathogens. Pathogens in the acute form are typically strep and staph, while in the chronic form it’s   Candida.  The acute form presents acutely tender and swollen with purulence. The chronic form is characterized by a boggy, ragged cuticle. Wet work (e.g., restaurant food prep, new moms) can predispose people to the chronic form. 

–  Is different treatment required for nail biters (i.e., different antibiotics)?  

 The type of paronychia tends to determine the treatment. Acute paronychia would get treated with antibiotics, and chronic paronychia would get treated with topical steroids and/or  antifungals  . Nail biting could predispose someone to either form. However, acute paronychia in nail biters would warrant treatment with antibiotics that specifi cally cover oral fl ora. 

–  When are oral antibiotics indicated?  

 Oral  antibiotics   are indicated for acute paronychia, and in practice I almost always treat with oral antibiotics. Treatment purely with topical antibiotics is generally not successful because it is diffi cult for them to penetrate the nail fold. I use cephalosporins and penicil-lins to treat staph and strep paronychia. Some paronychias are caused by   pseudomonas   , most commonly following manicures. They can be identifi ed by a blue-green hue to the purulence and lateral nail fold. Those cases can be treated with ciprofl oxacin. 

–  How do you know when to I&D? If it doesn’t seem ready to I&D, what is the best

treatment?  

 The decision to I&D comes down to the extent of the abscess and edema. Acute paronychia is generally a tiny abscess. If it’s very tender and very swollen, I will try to drain it. If it is only a little bit pink and tender, and it is not ready to I&D, I try oral antibiotics fi rst. I also consider whether the patient can tolerate the potential pain of the procedure. 

–  Are there common mistakes made when doing an I &  D     for paronychia?  

 The strong part of the nail is proximal to the proximal nail fold. That is where the matrix is located, which would need to be avoided in such a procedure in order to avoid causing damage. Any procedure done on the side of the nail is well away from the matrix, so the risk of causing permanent dystrophy is low. I often need to try a couple of punctures before finding the pus pocket. 

–  Can paronychia resolve with warm water soaks and topical antibiotics alone?

Should anything be put in the water?  

 Usually it cannot, but warm water soaks and hot compresses can be added as adjunctive therapy. It is helpful to massage the area after a 20-min soak or hot compress. 

Massaging can get the abscess to open up on its own and drain. Treatment exclusively with hot compresses and warm water soaks is not recommended except in very mild cases, and should only be used if a patient is very resistant to using antibiotics. The next step if paronychia advances is dactylitis, where infection extends to the fi nger pad, and that is a much bigger problem. The compresses can be done with warm water, Burow’s solution, or vinegar dissolved in a 1:1 ratio with warm water.     

   References 

1.    Shafritz AB, Coppage JM. Acute and chronic paronychia of the hand. J Am Acad Orthop Surg. 2014;22(3):165–74.

2.    Rigopoulos D, Larios G, Gregoriou S, Alevizos A. Acute and chronic paronychia. Am Fam Physician. 2008;77(3):339–46.

3.   Ritting AW, O’Malley MP, Rodner CM. Acute paronychia. J Hand Surg Am. 2012;37(5): 1068–70.

4.   Tully AS, Trayes KP, Studdiford JS. Evaluation of nail abnormalities. Am Fam Physician. 2012;85(8):779–87.

5.    Shaw J, Body R. Best evidence topic report. Incision and drainage preferable to oral antibiotics in acute paronychial infection? Emerg Med J. 2005;22(11):813–4.

6.   Tosti A, Piraccini BM, Ghetti E, Colombo MD. Topical steroids versus systemic antifungals in the treatment of chronic paronychia: an open, randomized double-blind and double dummy study. J Am Acad Dermatol. 2002;47(1):73–6.

7.    Hay RJ. The management of superfi cial candidiasis. J Am Acad Dermatol. 1999;40(6 Pt 2): S35–42.