Acute exantematic pustulosis generalized by meropenem, differential diagnosis with COVID

ABSTRACT

Case report We present the case of a 63-year- old man with two consecutive admissions, due to COVID19 infection and subsequent bacterial superinfection. Three days after the second admission (04/28), and 43 days from the beginning of the infection an assessment by dermatology and allergology is then requested. The patient had generalized erythematous maculopapular rash in the trunk, back, groin and limbs. On the left side and back, pustular lesions not focused on follicles were also added, with a fever of 37.7degreeC. There were no oral and genital lesions. No psoriasis. The drugs used during the present and previous admissions were reviewed. Previous admission (04/04-22/ 20) Linezolid, ciprofloxacin, meropenem 04/13-22, piperacillin/tazobactam, hydroxychloroquine, azithromycin, ceftriaxone. Upon discharge amoxicillin/acid clavulanic. Present admission (04/25) Cutaneous reaction 04/28. 04/25 meropenem, paracetamol, enoxaparin, insulin, omeprazole, venlafaxine. 04/26 Darbepoetin, furosemide, mycophenolate in single dose. 04/27 Linezolid, macrogol, Clopidogrel, Magnesium, Calcitriol. Medical records DM type 2, liver transplantation due to HCV cirrhosis, HCV recurrence, uninodular hepatocarcinoma, advanced CKD, secondary hyperparathyroidism, multiple neurological antecedents. We performed a detailed study. We hypothesized with a pharmagological/ drug reaction with several drugs possibly involved and our main suspicion was an allergic reaction to beta-lactams. Biopsy Subcorneal pustules, basal spongiosis and presence in the superficial dermis of edema and an inflammatory infiltrate with abundant neutrophils. No fungi. Findings compatible with clinical diagnosis of generalized acute exanthematic pustulosis (PEGA). Immunohistochemical study Covid19. (Jimenez Diaz Foundation) Finely granular positivity in endothelium and more coarse in sweaty epithelium. Neutrophilic superficial inflammatory component with presumably spure staining. ACe-2 (positive external control) is not detected. The patient presents a EuroSCAR score of 9, sum of the clinic and the pathological anatomy, and therefore defined diagnosis. Clinical diagnosis PEGA secondary to meropenem. Conclusion(s) We present the case of a PEGA by meropenem, not very often described in the literature. We highlight the importance of differential diagnosis with viral infections. Skin tests, especially epicutaneous tests, are key to the diagnosis. (Figure Presented).