Hydration Disorders

Question 1

What are characteristics of Sweat Glands?

Answer 1

• Play a key role in the thermoregulation of the skin
• 3 types of sweat glands
• Innervated by sympathetic (Cholinergic) nerve fibres (fight or flight) - particulary acetycholine
• Induced by cholinergic drugs and blocked by anticholinergic drugs

Question 2

What is the function of sweat?

Answer 2

• Cools the skin as it evaporates
• Excretes waste products
• Provides the epidermis with water to hydrate the skin
• Provides a protective anti-microbial substance

Question 3

What is hyperhidrosis?

Answer 3

• Excessive production of sweat from the eccrine glands
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Question 4

What is the aetiology of Hyperhidrosis?

Answer 4

• Adolescence
• Stress
• Menopause
• Obesity
• Endocrine disorder
  
  • Hyperthyroidism
  • Diabetes
• CNS disorder
  
  • Effect on sympathetic (cholinergic) nerve fibres
  • Alcoholism

Question 5

What is the pathology of Hyperhidrosis?

Answer 5

• Secondary to a central cortical problem rather than eccrine pathology
• Patients are capable of producing up to 10L of sweat per day
• Excess production of sweat and lack of evaporation can result in maceration of the skin
• Effects epidermal barrier function
• Skin unable to withstand stress

Question 6

What are clinical features/observations of Hyperhidrosis?

Answer 6

• Can increase stresses and forces across the foot which can lead to:
  
  • Blistering
  • Peeling of the skin
  • ‘bubbly’ soft callus
  • Fissures - fungal/bacterial infections
  • Burning pain/discomfort

Question 7

What is the treatment of Hyperhidrosis?

Answer 7

• Debridement of callus and fissures if necessary
• Skin care advice
• Topical therapy
• Referral to dermatologist

Question 8

What topical therapies are used to treat Hyperhidrosis?

Answer 8

• Astringents
  
  • Surgical spirits
  • Silver nitrate <20% solution
  • Salicylic acid 3%
• Aluminium chloride solution
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Question 9

What is Pitted Keratolysis

Answer 9

Superficial bacterial infection that affects the soles of the feet

Question 10

What are clinical characteristics/obversations of Pitted Keratolysis?

Answer 10

• Whitish skin and clusters of punched out pits
• Coalesce (formed together) crater like regions
• Hyperhidrosis
• Punctuate erosions
• Tender on weight-bearing area

Question 11

What is the aetiology of Pitted Keratolysis?

Answer 11

• Associated with hyperhidrosis
• Bacteria:
  
  • Corynebacteria
  • Dermatophilus congolensis
  • Kytococcus sedentarius
  • actinomyces
  • streptomyces
• Pitting is due to the destruction of stratum corneum due to protease enzyme produced by bacteria
• Malodour due to sulfur compounds produced

Question 12

What is the treatment of Pitted Keratolysis?

Answer 12

• removal of causative organism, and hyperhidrosis treatment
• Topical antibiotics:
  
  • Erythromycin
  • clindamycin
  • fusidic acid
  • benzoyl peroxide