Exanthematous (Morbilliform) Drug Eruptions in Patients with Darker Skin

00:01 Welcome to our lecture on Exanthematous or Morbilliform drug eruption.

00:08 This is also known as maculopapular morbilliform or measles like drug induced exanthem. It is the most common cutaneous drug reaction and accounts for about 80 to 90% of all cutaneous drug eruptions.

00:27 This reaction occurs as a type IV delayed type T cell-mediated hypersensitivity reaction. It can be caused by any drugs, but the highest rates are reported for antibiotics and anticonvulsants.

00:46 Patients who are newly exposed to the drug may develop symptoms within 7 to 10 days of initiating treatment, and clinically it may present with erythematous or rather grayish in dark skin.

01:02 And these are my tools and or patches or papules that one sees on the skin, hence maculopapular rash.

01:10 It predominantly involves the trunk and sometimes the proximal extremities.

01:18 Mild systemic symptoms and low-grade fever and generalized pruritis may be associated with morbilliform drug eruption.

01:30 The diagnosis involves a detailed history of recently administered drugs as well as physical examination. Laboratory testing includes taking bloods for the liver and the kidney to actually look for systemic involvement, as well as a full blood count.

01:51 The skin biopsy is only indicated in cases of uncertain diagnosis.

01:57 We sometimes do a drug challenge test to rule out or confirm drug hypersensitivity, where it is indicated, and there is a protocol for each drug in terms of doing a drug challenge test.

02:13 The differential diagnosis includes early stages of Stevens-Johnson syndrome or toxic epidermal necrolysis. What is unique about this condition is that you here you do get mucosal involvement, but sometimes it can be very difficult to distinguish between the two. Viral and bacterial exanthem is another differential, and this one usually occurs after an incubation period specific to that particular infective agent. Secondary syphilis, the great mimicker can also be a differential for this condition. And here one gets typical symmetrical rash involving the trunk extremities. Particularly, involvement of the palms and soles is usually an indicator that one may be dealing with syphilis, although some drug reactions may also involve the palms and soles.

03:10 The management includes identifying the causative medication and discontinuing or replace if possible. Symptomatic treatment forms part of the management.

03:23 Using emollients and potent topical steroid creams 1 to 2 times per day for one week or until resolution is recommended, sometimes with reps for for very red and inflamed skin are actually used for patients.

03:40 Antihistamines are often prescribed but not very helpful.

03:44 And don't forget to use analgesics, because patients with drug reactions do experience severe pain from the inflammation of the skin.

03:55 Depending on the severity, the patient may require oral steroids for short periods, and sometimes intravenous immunoglobulins have been used.