Necrotic ulcers in an immunocompromised patient

Abstract

A 68-year-old man presented to dermatology clinic with extensive ulcers for one-week duration. Patient had underlying uncontrolled Type II Diabetes Mellitus and pemphigus foliaceous. His medications were metformin 1 g twice daily, prednisolone 30 mg daily and azathioprine 50 mg daily. He denied fever, prior trauma or insect bites. On examination, there were multiple necrotic ulcers of varying sizes present on the anterior trunk and extensors of left knee (Fig. 1A & B). Some of the lesions were exudative with serous discharge. The surrounding skin was erythematous. Blood investigation revealed leucocytosis at 15,000 cells per cubic millimetre and a raised C-Reactive Protein (CRP) at 8 mg/dL. Patient was empirically started on intravenous piperacillin-tazobactam 4.5 g thrice daily to cover for bacterial skin infection. Four days later, swab from the lesion yielded Pseudomonas Aeruginosa with sensitivity towards ceftazidime. Blood culture revealed no growth. Antibiotic therapy was changed to intravenous ceftazidime 1 g thrice daily. Surgical debridement of the necrotic patches was done twice, followed by bactigrass and duoderm dressing. After 1 week of therapy, patient remained well with no new ulcers formed. Inflammatory markers such as total white cell counts and CRP have normalised too. Hence, he was discharged home. What is the diagnosis? Ecthyma gangrenosum. Ecthyma gangrenosum (EG) is a haemorrhagic and necrosing vasculitis of the small vessels, commonly associated with Pseudomonas Aeruginosa [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar]. Risk factors include neutropenia, malignancies, immunosuppressive treatments and diabetes mellitus. [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar, [2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] EG presents with painless erythematous macules, with or without vesicles. Within 12–24 h, the lesions become indurated with haemorrhagic blisters. Finally, deep-necrotic ulcers with a grey-black eschar formed with a surrounding erythematous halo. [[2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] Most common affected sites are perineal (57%), distal extremities (30%), facial and truncal (12%)[[2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar]. Clinical assessment is sufficed to diagnose EG. Culture from tissue or swab of lesion may identify the causative pathogen. [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar, [2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] Blood culture is recommended if bacteraemia is suspected. [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar] Empirical treatment with anti-pseudomonal antibiotic is recommended if the diagnosis of EG is suspected. [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar, [2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] Once the causative organism and its sensitivity are identified, targeted therapy of a single antimicrobial agent is administered until improvement of lesions is observed. Surgical debridement is indicated in extensive cutaneous lesions, abscess or non-responsive to medical therapy alone. [[1]Vaiman M. et al.Ecthyma gangrenosum and ecthyma-like lesions: review article.Eur J Clin Microbiol Infect Dis. 2015; 34: 633-639https://doi.org/10.1007/s10096-014-2277-6Crossref PubMed Scopus (112) Google Scholar, [2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] This case emphasizes the need to recognise EG and deliver suitable treatment early. Delay in diagnosis may result in fatal outcome as the mortality rate ranges from 38% to 77%. [[2]Bettens S. et al.Ecthyma gangrenosum in a non-neutropaenic, elderly patient: case report and review of the literature.Acta Clin Belg. 2008; 63: 394-397https://doi.org/10.1179/acb.2008.081Crossref PubMed Scopus (18) Google Scholar] Informed consent of the patient has been obtained to publish his case and images in the manuscript. The authors declare that they have no competing interests.