Pitted Keratolysis

Background

• Pitted keratolysis refers superficial skin condition that affects the feet. The feet are covered by pits that are largely asymptomatic.
• In many cases, pitted keratolysis exhibits random episodes of occurrence and disappear just as spontaneously ^[1]. As such, the condition can affect the person for several years if it is left untreated.
• To effectively treat the condition the wet and warm conditions that promote the reproduction and growth of the causative bacteria have to be controlled first.
• Most prevalent among individuals with hyperhidrosis (profuse sweating) especially when they have to go long periods of time in closed shoes ^[2].

Symptoms

• Pits – 1  to 3 mm in diameter ^[3]
• However, the pits may overlap leading to a larger lesion ^[4].
• Smelly feet. This is the major cause of anxiety among the sufferers
• The heel, the forefoot, or both become covered with punched out sores that make them white in color. This is because these areas are subjected to the weight of the body ^[2].
• In a certain type of the condition, some red spots appear on the sores ^{[2, 4]}
• Sometimes the hands and fingers are also affected ^[5]
• The sores are usually asymptomatic and most people seek medical attention due to the foul smell and embarrassment caused by the sores ^{[1, 3]}
• Some patients claim to feel some irritation but it is mild.
• The skin in some areas of the feet may be white and swollen.

 

Image 1: Lesions characteristic of pitted keratolysis
Picture Source: skinsight.com

Causes

• The condition is caused by a host of gram-positive bacteria. They include: Kytococcus sedentarius, Dermatophilus congolensis, streptomyces and actinomyces ^[5].
• Enclosed feet, hyperhidrosis and high skin pH offer the optimum conditions for these bacteria to reproduce and produce digestive enzymes-proteases ^[3].
• The proteases digest the foot skin (stratum corneum) proteins resulting to the cater-like pits which develop into sores ^[5]
• The foul odor has been attributed to the sulphur compounds that the bacteria release as products of metabolism ^[6]

 
Image 2: Hands of a person with profuse hyperhidrosis
Photo Source: homeremediesorg.com

Who is at Risk?

• Pitted keratolysis has been observed to be more likely to infect men. This may be because men are more inclined to wear occlusive, non-breathing footwear to work or school. ^[6]
• People of all ages can be infected by the bacteria and subsequently get the illness.
• It is a common condition among athletes, construction and industrial workers, and people in the military because of the requirements that they be in boots most of the time ^[7]
• Anyone working in wet/moist conditions such as people working in swimming pools, spas, and paddles ^[6,7]
• Sweaty feet or palms also predispose individuals to the illness ^{[2, 8]}.

Diagnosis

• Clinical assessment of the patient’s signs and symptoms.
• Using as swab to take a probe for lab analysis to help identification of the causative microorganism.
• In case there is suspicion that the infection has been caused by different strains of fungi, the skin can be scrapped for examination and confirmation ^[4].
• Skin biopsies are rarely necessary since the diagnosis can be done easily owing to the characteristic pits and the odor ^[9].
• The Wood’s ultraviolet light test is inconsistently helpful. The affected surface shows a distinctive red fluorescence ^[9].
• The causative bacteria may be collected from the pits. They can then be cultured on a medium with brain-heart infusion agar. The culture is placed under nitrogen and carbon dioxide. Temperature should be 98.6oF (37o).

Management

Preventive measures

• Minimize the use of closed footwear and where it is unavoidable wear shoes that fit properly to limit friction on the ^[6].
• Keep feet always dry. After washing them, one can use a hair blow dryer to dry them up ^[4].
• Wear clean cotton socks. They should be washed and changed frequently [pcds].
• Those prone to the illness should also avoid wearing a pair of shoes for more than two consecutive days ^[4].
• Use innersoles that are designed to absorb moisture when wearing closed shoes. Just like socks, the innersoles should be changed frequently.
• Whenever possible, the feet should be let out of the shoes to breathe ^{[5, 7]}.
• Don’t share towels with others ^[10]
• Use an antiseptic to wash the feet twice a day. Dry them properly ^[10]
• People involved in sports and working out should not linger in their footwear after sweaty exercises. After the exercise or workout, it is recommended that one wears open shoes with adequate ventilation.

Image 2: Feet require special treatment to manage Pitted Keratolysis
Picture Source: wisegeek.com

Cure and Home Treatment

• Palmoplantar hyperhidrosis causes profuse sweating of the palms and feet. It is necessary to treat the condition first before trying to treat pitted keratolysis.
• A solution of 5% formaldehyde solution is effective in cases of extremely wet feet where other techniques used to dry the feet have not succeeded ^[1]. The solution can only be obtained with a prescription and it is relatively expensive.
• Prescribed strength-antiperspirant powder applied in the socks and shoes will minimize the perspiration. As a result the environment will be unsuitable for the bacteria to thrive ^[10].
• When used in combination with the preventive measures, topical antibiotics work in a span of 3-4 weeks ^[6]
• Clindamycin, erythromycin preparations or Fucidin cream applied twice a day has also been noted t treat pitted keratolysis ^[2]
• Many cases have been reported where individuals have successfully treated the condition by applying acne medication with 10% benzoyl peroxide the part of foot that is infected ^[1].
• Oral erythromycin has also been reported to be effective in some instances ^{[2, 6]}.
• In severe cases injections of the botulinum toxin may be administered ^[11].
  Is Pitted Keratolysis contagious?
• Unlike most of other infections caused by bacteria, pitted keratolysis is not contagious a contagious medical condition ^[4].
• However, it is advisable to maintain good personal hygiene. It is also recommended that people do not share personal objects of hygiene such as towels amongst each other because it may lead to secondary infections ^[4].

References :

1. Pitted Keratolysis. Treatment [Internet]. 2012 [cited 20 January 2016]. Available from: http://www.pittedkeratolysis.com/treatment/
2. Dermnetnz.org. Pitted keratolysis. DermNet NZ [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.dermnetnz.org/bacterial/pitted-keratolysis.html
3. Podiatrytoday.com. A Review Of Treatment Options For Pitted Keratolysis | Podiatry Today [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.podiatrytoday.com/blogged/review-treatment-options-pitted-keratolysis
4. Medicalpoint.org. Pitted Keratolysis – Treatment, Pictures, Symptoms, Contagious [Internet]. 2016 [cited 20 January 2016]. Available from: http://medicalpoint.org/pitted-keratolysis/
5. Emedicine.medscape.com. Pitted Keratolysis: Background, Pathophysiology, Epidemiology [Internet]. 2016 [cited 20 January 2016]. Available from: http://emedicine.medscape.com/article/1053078-overview#showall
6. Pcds.org.uk. Pitted keratolysis [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.pcds.org.uk/clinical-guidance/pitted-keratolysis
7. Gustrength.com. Pitted and Smelly Feet: Pitted Keratolysis – Ground Up Strength [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.gustrength.com/health:pitted-and-smelly-feet-pitted-keratolysis
8. Khachemoune A, T. Klausner B. Smelly, Macerated Feet Diagnosis: Pitted keratolysis (PK) | The Dermatologist [Internet]. The-dermatologist.com. 2016 [cited 20 January 2016]. Available from: http://www.the-dermatologist.com/article/851
9. Pitted keratolysis. Indian Journal of Dermatology, Venereology and Leprology [Internet]. 2005 [cited 20 January 2016];71(3):213-215. Available from: http://www.ijdvl.com/article.asp?issn=0378-6323;year=2005;volume=71;issue=3;spage=213;epage=215;aulast=
10. Med-health.net. Get Rid of Pitted Keratolysis Completely | Med-Health.net [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.med-health.net/Pitted-Keratolysis.html
11. Skinsight.com. Pitted Keratolysis in Adults: Condition, Treatment and Pictures – Overview | skinsight [Internet]. 2016 [cited 20 January 2016]. Available from: http://www.skinsight.com/adult/pittedKeratolysis.htm