What is Symmetrical Drug-Related Intertriginous and Flexural Exanthema?
Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) refers to a red skin rash that usually shows up on the buttocks and folds of the skin, such as the inner thighs, after taking certain medications. Back in 1984, it was given the nickname ‘baboon syndrome’. This was because the rash, which would show up after using some drugs or allergens, would appear on areas like the buttocks and inner thighs, somewhat like the red-bottomed appearance of baboons.
In 2004, the term SDRIFE was introduced by Hausermann as a more accurate name for these reactions when they happen after taking medications, no matter whether the person had never had such a reaction before. What makes SDRIFE different from other drug-caused skin reactions is its typical shape, locations it appears, and the fact that it there are no linked symptoms affecting the whole body.
What Causes Symmetrical Drug-Related Intertriginous and Flexural Exanthema?
Beta-lactam antibiotics like amoxicillin often lead to a skin condition called symmetrical drug-related intertriginous and flexural exanthema, which is a reaction to some medications. They are the most common triggers for this skin condition. But, there are reports of many other medications causing the same reaction. These include non-beta-lactam antibiotics (i.e., not part of the amoxicillin family) such as pristinamycin, clindamycin, erythromycin, roxithromycin, and cotrimoxazole.
Other types of infection-fighting medications such as nystatin, terbinafine, fluconazole, metronidazole, and valacyclovir have also been linked to this skin condition.
Reports show that other types of drugs such as codeine, pseudoephedrine (a decongestant), cimetidine (used to reduce stomach acid), allopurinol (for gout), heparin (a blood thinner), and others like hydroxyurea, oxycodone, naproxen, risperidone, ethyl loflazepate (a sedative), antihypertensives (for high blood pressure), iodine radiocontrast media (used in some X-rays), chemotherapeutic drugs (for cancer), and monoclonal antibodies like infliximab can also cause this skin reaction.
Even topical agents, which you apply to your skin, like bufexamac (anti-inflammatory) and 5-fluorouracil (for cancer), have been reported to cause this skin condition.
Risk Factors and Frequency for Symmetrical Drug-Related Intertriginous and Flexural Exanthema
Despite not being very common, Symmetrical Drug-Related Intertriginous and Flexural Exanthema (or SDRIFE) has been reported in over 100 cases since 1984. It’s also known as the ‘baboon syndrome’. Patients across all ages, ranging from 18 months to 84 years can be affected by SDRIFE. Both genders can get SDRIFE but it tends to be more common in males.
- SDRIFE isn’t very common but over 100 cases have been reported since 1984.
- This condition can affect patients of any age, from as young as 18 months to as old as 84 years.
- Both males and females can get SDRIFE, but it’s more commonly seen in males.
Signs and Symptoms of Symmetrical Drug-Related Intertriginous and Flexural Exanthema
Symmetrical drug-related intertriginous and flexural exanthema is a condition that could emerge a few hours to a few days after removing the medication that caused it. The diagnosis is based primarily on the very specific appearance of the rash. This includes the rash spreading to the buttock and folds of the skin, and the even distribution of the lesions.
Specific diagnostic criteria involve five key factors:
- Taking a medicine (not including topical allergens) that could have caused the rash
- Distinctly bordered red skin inflammation found on the buttock, near the anus, groin, or genitals
- At least one skin fold area is affected
- Both sides of the body have a similar pattern of affected areas
- No symptoms experienced in the overall body
The skin lesions are commonly described as red spots or lumps, or raised red areas. Rare cases have unusual progressions like pus-filled bumps, small raised spots, blisters, or patches of bleeding under the skin. It generally doesn’t affect the mucous membranes, and it’s very rare for it to affect the face and the palms or soles of the feet.
Testing for Symmetrical Drug-Related Intertriginous and Flexural Exanthema
A diagnosis for skin reactions following drug ingestion, otherwise known as SDRIFE, is primarily based on what symptoms you’re experiencing, your health history, and ruling out other reasons for your skin rash. Lab tests might be done to make sure that other parts of your body, like your blood cells, liver or kidneys, aren’t affected, but these tests aren’t typically needed to diagnose SDRIFE itself.
If it’s necessary to determine the specific drug causing your skin reaction, a few different tests could be used. Patch tests, lymphocyte transformation tests, and drug provocation tests (DPT) could all provide useful information, but the results can vary greatly from person to person.
Patch tests, which involve putting a small amount of the suspected drug on your skin to see if it causes a reaction, are usually the first type of test to be done. But while these tests are straightforward, they may not give a sure-fire answer. In past studies, only about half of the people tested had a positive reaction. This may be because the drug doesn’t fully soak into the skin during the patch test.
Considered the most reliable test, DPT involves taking the suspected drug under controlled conditions to see if it causes a reaction. This test has indicated positive results in the majority of people with SDRIFE, and has thus been used to confirm reactions to various drugs- like clindamycin, cimetidine, corticosteroids, turbine, and valacyclovir.
Treatment Options for Symmetrical Drug-Related Intertriginous and Flexural Exanthema
Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) is a condition that typically goes away on its own. It is usually treated by stopping the use of the medication that caused it and providing other treatments to help manage symptoms. Some of these other treatments can include systemic steroids (medications designed to reduce inflammation throughout the body) or topical steroids (creams or ointments applied to the skin), which can help speed up healing. Antihistamines, a type of medication that can alleviate itching, are also often used to manage symptoms.
What else can Symmetrical Drug-Related Intertriginous and Flexural Exanthema be?
When doctors diagnose specific skin conditions, they must rule out several other potential diseases first. These might include:
- Seborrheic dermatitis
- Intertrigo
- Allergic contact dermatitis
- Inverse psoriasis
- Granular parakeratosis
- Darier disease
- Hailey-Hailey disease
Only after excluding these conditions can a doctor make a diagnosis of a drug eruption.
Furthermore, the condition known as SDRIFE can often look like other reactions to drugs. These include:
- Acute generalized exanthematous pustulosis (AGEP)
- Drug reaction with eosinophilia and systemic symptoms (DRESS)
- Fixed drug eruption (FDE)
But, it’s important to note that AGEP and DRESS usually result in a widespread rash accompanied by other body-wide symptoms. FDE can be easily told apart from SDRIFE as it typically presents with uneven patches or plaques on the extremities, genitals, and mucus membranes, which are often round or oval. After the rash heals, it usually leaves behind an area of darker skin.
What to expect with Symmetrical Drug-Related Intertriginous and Flexural Exanthema
The outlook for SDRIFE (Symmetrical Drug-related Intertriginous and Flexural Exanthema), a skin reaction caused by certain drugs, is generally positive once the medication causing the problem is stopped.
Possible Complications When Diagnosed with Symmetrical Drug-Related Intertriginous and Flexural Exanthema
Symmetrical drug-related intertriginous and flexural exanthema is a type of harmless skin rash. This condition usually improves on its own without any complications. In rare cases, there may be some minor complications.
Common Characteristics:
- Harmless skin rash
- Typically improves on its own
- Rare complications
Preventing Symmetrical Drug-Related Intertriginous and Flexural Exanthema
There is a type of drug reaction called symmetrical drug-related intertriginous and flexural exanthema. This basically means a symmetrically occurring rash in the folds of the skin caused by certain medications such as beta-lactam antibiotics, radiocontrast media (used in certain medical imaging tests), monoclonal antibodies, and other drugs. Considering how often these treatments are used, it’s really important for patients to be aware that a drug reaction could happen. If it does, the best thing to do is to reach out to their doctor right away.
