Irritant contact dermatitis M028

Current RMA Instruments

Changes from previous Instruments

ICD Coding

• ICD-9-CM Codes: 692.89
• ICD-10-AM Codes: L24

Brief description

This SOP covers inflammation of a localised area of skin due to contact with that area of skin by an irritant substance. See comments below for further information.

Confirming the diagnosis

Diagnosis is made clinically based on the exposure history and findings on examination.  Patch testing may be performed to exclude allergic contact dermatitis.  Skin biopsy may be necessary in some cases.

The relevant medical specialist is a dermatologist.

Additional diagnoses covered by SOP

• Nil

Conditions not covered by SOP

• Allergic contact dermatitis*
• Photocontact dermatitis*
• Systemic contact dermatitis^#
• Sunburn - not a disease
• Dermatitis due a substance taken internally^#

* another SOP applies

^# non-SOP condition

Clinical onset

Clinical onset will be within three days of the relevant irritant exposure.  Irritant contact dermatitis can be an acute self-limiting condition or a chronic condition if there is regular exposure to an irritant.  Acute irritant contact dermatitis should fully resolve within 10 weeks of cessation of exposure to the causative irritant.  Any subsequent recurrence would represent a new clinical onset.   Chronic irritant dermatitis can be an ongoing condition and persist longer term after exposure to the irritant has ceased, but enduring symptoms/signs generally indicate that there has not been complete elimination of irritant exposure.  If the condition resolves and then later recurs on new exposure to irritants then that is a new clinical onset.

Clinical worsening

Permanent clinical worsening attributable to service should not generally be a feature of this condition.  Persistent worsening would require persistent exposure to irritants.

Comments

Dermatitis is a non-specific diagnostic label meaning inflammation of the skin.

A contact dermatitis is where the aetiological agent comes into contact with the skin and the skin responds at that site of contact with local inflammation.

Classification of contact dermatitis:

• Topical skin agent -> local skin normal inflammatory response = Irritant contact dermatitis
• Topical skin agent -> local skin allergic inflammatory response = Allergic contact dermatitis
• Topical skin agent + topical light exposure -> allergic or normal inflammatory response = Photocontact dermatitis
• Topical skin agent -> local skin allergic inflammatory response; then, systemically absorbed agent -> skin allergic inflammatory response = Systemic (Allergic) contact dermatitis

(Topical means local.)

Irritant contact dermatitis is a normal inflammatory skin response to a toxic agent and this will occur to some degree in all normal persons. An example would be detergent contact irritant dermatitis.

Persistence of the irritant dermatitis is not contributed to by past exposure.  Irritant contact dermatitis will cease to be related to service after cessation of that service, being attributable instead to post-service exposure to contact irritants.

The other major type of contact dermatitis is allergic contact dermatitis, in which there is an abnormal inflammatory skin response. This abnormal inflammatory skin response is an allergic response which is instigated by an earlier exposure. The earlier exposure does not need to be topical. Subsequent topical exposures to the same allergen will produce an allergic response at the site of skin contact.  In this case, on cessation of service, there will still be a potential residual link to service for ongoing or recurrent allergic contact dermatitis, if clinical onset occurred during service, for the same allergen as is causative for the post service condition.