Dermatology

Diaper Rash

Introduction

Diaper rash is a general term that describes any inflammatory skin eruption in the diaper covered area.  Rashes in the diaper area are one of the most common problems encountered in infants and toddlers, representing 10-20% of all skin disorders seen by a general pediatrician. Peak incidence occur between 9-12 months.

There are two main categories of diaper dermatitis: rashes associated with diaper use and rashes not associated with diaper use.

Diaper Associated

Diaper Dermatitis

Irritant diaper dermatitis.jpg
https://en.wikipedia.org/wiki/Irritant_diaper_dermatitis

  • This is the most common cause of diaper rash and is due to irritant contact dermatitis resulting from the combination of localized physical, chemical and mechanical irritation (such as from urine, feces, friction, and moisture). 
  • The rash is usually over the areas in contact with the wet diaper- buttocks, lower abdomen, medial thighs, labia, mons pubis, and scrotum. Because of the lack of contact, the fold areas are usually spared. 
  • The rash is erythematous, papular, and has areas of scaling. The skin appears edematous and inflamed causing the infant to be irritable. With chronicity, the skin will get dry. Chronic irritation can lead to ulcerations—this is known as Jacquet’s erosive diaper dermatitis and likely represents the severe end of the spectrum of irritant diaper dermatitis.
  • Because of increased moisture, there is a change in the permeability of the epidermis allowing increased entrance of irritants and increased susceptibility to frictional damage from diaper. This is enhanced by stool enzyme activation (urease), interacting with urine to increase pH in order to further irritate and damage skin.
  • Secondary bacterial and yeast infections are common.
  • Prevention and Treatment
             
    • The key is prevention: maintaining dry, protected skin is vital. Allowing diaper-free intervals is recommended but not always practical. Frequent diaper changes are essential for minimizing skin exposure to urine and feces and keeping the infant dry. It is recommended that newborns be changed hourly, and older children every 3–4 h. Although there is debate regarding cloth versus disposable diapers, studies have shown superabsorbent disposable diapers cause less erythema than cloth diapers when changed at appropriate intervals. 
    • Decrease scrubbing of the area when changing
    • Use only warm water or mild soaps with a soft cloth for clensing
    • Barrier creams or thick, adherent pastes containing zinc oxide, titanium dioxide, and starch, or creams with dexpanthenol that may be used to prevent contact of feces with skin, avoid humidity and minimize transepidermal water loss. Pastes should be applied liberally and can be covered with petroleum jelly to avoid sticking to the diaper. Bathing should be performed daily in lukewarm water with a mild, irritant-free and fragrance-free cleanse.
    • Cornstarch and other powders will keep area dry and decrease friction. Avoid inhalation of powder that can lead to aspiration. 
  • Anti-inflammatory topical steroid are useful if above measures fail. Use only low potency steroids for short periods (no more than twice daily for 1 week). The diaper area has very thin skin, and the use of potent topical steroids may lead to thinning, striae, and adrenal suppression. Avoid combination preparations of antifungal and steroids because the steroid is usually high potency and should not be used in the diaper area.
  • Antibiotics may be necessary for secondary bacterial infection.  Topical mupirocin should be used over Neosporin because of neomycin’s allergic properties.

Candida Diaper Rash

  • Can result due to untreated irritant dermatitis becoming secondarily infected.
  • Classic presentation: Beefy red rash with satellite papular lesions and superficial pustules that leave a collarette of scale once ruptured. Usually involves the folds and often well demarcated.
  • Check for oral thrush because occur together
  • May be associated with prior antibiotic use or diarrhea. 
  • Confirm diagnosis with KOH stain demonstrating pseudohyphae or use fungal culture.
  • Treat with ketoconazole, clotrimazole, econazole, or nystatin. Must treat contact dermatitis and inflammatory changes as well. Steroid and antifungal can be applied together if necessary.
  • Keep area dry and change frequently.
  • If recurs, check for sources of fungus on mother's breast, vaginal area, and pacifiers.  Recurrent candida diaper rash can also be a sign of underlying type I DM, chronic mucocutaneous candidiasis, or an underlying immune deficiency.

Allergic Dermatitis

  • Allergic contact dermatitis (ACD) should be considered when dermatitis persists despite treatment efforts. It generally appears in areas exposed to the offending agent and spares the inguinal folds.
  • ACD can develop from constituents of the diaper or to products applied to the area by the caregiver. Common allergens include sorbitan sesquioleate, which acts as an emulsifier in topical preparations, fragrances, disperse dye used to impart color, cyclohexylthiopthalimide and mercaptobenzothiazole used in rubbers, and iodopropylcarbamate and bronopol used in baby wipes. 
  • Classic presentation: well demarcated erythema, papules with scale, vesicles, or erosion in diaper area

Non Diaper Associated

Bacterial Diaper Rash

  • Superficial Staphylococcal infection most common with 1-2mm fragile pustules and honey-colored, crusted lesions.  Can also cause bullous form with large, flaccid, pus-filled bullae that rupture easily and leave erosions with a collarette of scale.
  • Gram stain and culture of pus to confirm diagnosis
  • Treat with topical Mupiricin or Neosporin. Extensive infection requires oral anti-staphylococcal coverage.

Seborrhea Dermatitis

  • Classic presentation: Well circumscribed, erythematous papules and plaques with greasy yellow scale most prominent in the skin folds. Often associated with cradle cap, axillary, antecubital, poplitial, and neck folds as well as lesions behind the ear.
  • Usually present at 2-3 weeks of life and disappears by 3-4 months. Not pruritic. Often secondarily infected with Candidiasis.
  • Responds to short term topical therapy low-potency steroids (ex: hydrocortisone cream )
  • Very severe, Leiner's disease phenotype, has been described with SCIDs, hypogammaglobulinemia, and hyperimmunoglobulinemia.

Atopic Dermatitis

  • Uncommon cause of rash in diaper area because the presence of the diaper prevents scratching. Vigorous scratching during diaper changes will occur—look for evidence of chronic scratching (increase in skin lines and excoriations).
  • Usually pos family history
  • Treatment is topically applied corticosteroids

Scabies

  • Acute, widespread, pruritic dermatitis
  • Presentation: erythematous papules, nodules, excoriations mostly on abdomen, web spaces of hands and feet, axilla, genitalia
  • Look for other family members with same symptoms
  • Diagnosis confirmed by identifying mite, egg, or stool on microscopic exam of scraping from lesion
  • Treatment: 1st line is topical permethrin with topical lindane

Langerhan's Cell Histiocytosis

  • Rare cause of severe diaper rash that is unresponsive to treatment; potentially life-threatening
  •  Red/orange or yellow/brown scaly papules, erosions, or petechiae in groin, intertriginous regions, and scalp
  • Often confused for seborrheic dermatitis—but lesion color and petechiae presence distinguishes the two.
  •  Systemic manifestations possible- anemia, lymphadenopathy, hepatosplenomegaly, bone lesions.
  • Skin biopsy required to confirm diagnosis

Acrodermatitis Enteropathica

  • Secondary to zinc deficiency
  • Scaly crusty plaques in diaper area as well as periorally. May have alopecia and paronychia.
  • May be associated with malabsorption syndromes.
  • Responds to zinc replacement

Congenital Syphilis

  • Copper colored maculopapular scaly rash.  Skin lesions contain spirochetes and are highly infectious.
  • Systemic symptoms- bony changes, desquamation of palms and soles, hepatosplenomegaly, jaundice, anemia.
  • Confirm with darkfield microscopy, treat with penicillin.

References:

  1. Ravanfar P, Wallace J, Nicole C. Diaper Dermatitis: a review and update. Current Opinion in Pediatrics. Volume 24(4), August 2012, p 472–479
  2. Horii K and Prossick A.  “Overview of Diaper Dermatitis in infants and children”.  UpToDate.com, version 18.2, accessed 9/27/10.
  3. Weston W and Howe W.  “Treatment of atopic dermatitis”.  UpToDate.com, version 18.2, accessed 9/27/10.