Case Presentation: New onset rash in a hospitalized patient is a frequent challenge. While common presentations of drug associated rash are readily recognized, less common presentations can be mis-identified. Here we present the clincal vignette of a 62-year-old female patient with a past medical history of hypertension who was hospitalized with severe COVID-19 pneumonia and develops a psoriasiform rash during her treatment course. The patient presented to the hospital 5 days after onset of dyspnea with a temperature of 36.5° C, heart rate 89, respiratory rate 16, blood pressure 109/60, and SpO2 90% on room air. Chest imaging revealed bilateral interstitial opacities and COVID-19 PCR was positive. Her COVID-19 pneumonia was treated with 5days of remdesivir, 4 days of dexamethasone, and 11 days of baricitinib. She also received treatment with ceftriaxone and doxycycline for possible bacterial pneumonia. In addition, she was started on lisinopril and metoprolol during hospitalization for elevated blood pressures. On hospitalization day 11, she developed pruritic erythematous papules with a scaly appearance grouped on bilateral flanks, lower extremities, and the plantar surfaces of feet. Skin biopsy revealed psoriasiform epidermal hyperplasia with overlying parakeratosis and intracorneal micropustules. Baricitinib, doxycycline, and metoprolol were considered possible culprits for eruption – doxycycline was already completed, baricitinib was discontinued, and benefit of beta blocker was felt to outweigh risk, so therapy was continued. She was treated with triamcinolone cream and had complete resolution of the rash at one month follow up.

Discussion: Here we present a case of psoriasiform rash in a hospitalized patient. Drug induced eruption was favored given acute onset, self-limiting nature, and exposure to several possible culprit medications. By far, the most common form of drug rash seen in hospitalized patients is the maculopapular exanthematous rash often seen with antibiotics, antiepileptics, and nonsteroidal anti-inflammatory drugs (NSAIDs). Less frequently, providers encounter more life-threatening drug rashes including urticaria/angioedema, bullous eruptions, drug reaction with eosinophilia and systemic symptoms (DRESS), or the feared Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN). Psoriasiform eruptions are less common, but have been most associated with beta-blockers, lithium, antimalarials, NSAIDs, and tetracyclines. Baricitinib has been associated with palmoplantar pustulosis, an uncommon condition related to psoriasis. While this patient did not have known underlying psoriasis, cases of psoriasis eruption in the setting of steroid withdrawal have been reported – as the rash was noted on the day following completion of dexamethasone, we also considered this possibility. Case reports have documented the development of psoriasiform rash following certain infections (primarily streptococcal infections), however, no cases to our knowledge have been reported secondary to COVID-19. The dermatologic manifestation most seen with COVID-19 is viral exanthem with morbilliform rash.

Conclusions: To optimize inpatient care, providers should readily recognize common and uncommon forms of drug rash, including psoriaform drug rash, as well as common offending agents.

IMAGE 1: Gross appearance of psoriasiform rash.

IMAGE 2: Skin biopsy with psoriasiform epidermal hyperplasia with overlying parakeratosis and intracorneal micropustules.