100109 - Toxic epidermal necrolysis due to fosfomycin

Toxic epidermal necrolysis (NET) is a severe, live threatening immune-mediatedreaction which is commonly initiated by certain drugs. Some antibiotics had beenlisted as associated with NET, such as levofloxacin or Doxycycline. We present acase of NET caused by fosfomicyn, which is not a drug usually related with NET orStevens-Johnson syndrome.We present the case of a 50 years old woman, wich due to an urinary tractinfection was prescribed fosfomicyn 3 grams for two days. 72 hours after the firstintake, the patient presented a maculopapular rash in her thighs as well aspethequias, as well as malaise. The patient went to the Emergency Room (ER)from which she was discharged after prescribing paracetamol and valacyclovir.In the next 24 hours this rash spread throughout the rest of the skin and someflaccid bullae started to appear in both arms, as well as fever (38ºC). She visitedonce again the ER and this time was admitted at the Hospital under the care ofInternal medicine. Her condition was initially treated as an herpetic infection. Itwas not until her general state worsened, with elevation of hepatic enzymes andincrease of the fever, and the serologies for herpes virus came back negative thatwe were contacted.After our diagnosis of NET caused by fosfomicyn the patient was admitted to theCritical Care Unit. Under their treatment and vigilance, our patient improved andafter two weeks she was discharged from the hospital with no further organicsequels.A prompt diagnosis of entities as life-endangering as NET should be taken intoconsideration in the differential diagnosis of any patient who presents anysuspicion of drug-induced blistering, since a delay in diagnosis in turn delayshospital admission, which could be fatal for the patient.