Emmonsia pasteuriana is a newly emerging dimorphic fungal pathogen first isolated in 1998 from a cutaneous disseminated infection in an Italian patient with human immunodeficiency virus (HIV) infection.1 In 2013, attention was drawn to 13 cases of disseminated E pasteuriana infection in South Africa.2 We present herein a case of cutaneous disseminated E pasteuriana infection in a patient with cytomegalovirus (CMV) enteritis in China.
A woman in her 30s presented a 3-month history of scattered asymptomatic cutaneous nodules. Medical history was significant for urticaria of 8 years’ duration and diarrhea of 14-months’ duration. She had received prednisone for 2 weeks to treat urticaria before the onset of skin nodules. At the time of presentation, she was emaciated and had no other known chronic medical conditions. She had not traveled recently but had had contact with a domestic hamster 1 month before skin lesion onset. Physical examination revealed four 1- to 2-cm diameter nodules with central ulceration or thick adherent crust on the left side of her face (Figure 1), left axilla, and bilateral forearms without lymphadenopathy. Findings of the general physical examination were normal.
Facial emmonsiosis lesion. Crusted nodule at the left corner of mouth.
Both skin lesion exudate smear and skin biopsy revealed numerous yeast cells within histiocytes; the yeast cells were rarely extracellular (Figure 2). Skin biopsy specimens yielded a thermally dimorphic fungus; morphologic characteristics and analysis by internal transcribed spacer sequence 5 DNA sequencing (GenBank accession number: sysu2014.sqn sysu2014 KP260922) identified it as E pasteuriana. Disk diffusion antifungal susceptibility testing revealed that the isolated fungus was sensitive to voriconazole, fluconazole, itraconazole, and amphotericin B. Fungal cultures of blood, urine, and stool clinical specimens were negative. Capsule endoscopy revealed ileal mucosa multiple hyperplasia and ulceration. Intestinal biopsy and immunostaining results were consistent with CMV enteritis; CD4+ and CD8+ lymphocyte counts were 570.96/mL and 287.92/mL, respectively. Findings of chest radiography and HIV antibody and serum immunoglobulin and complement C3 and C4 evaluation were normal.
A, Numerous oval yeast cells within histiocytes; extracellular yeast cells were rare (Wright’s stain of skin lesion smear, original magnification ×100). B. Numerous oval yeast cells within histiocytes and some narrow-based budding yeast cells; extracellular yeast cells were rare (Grocott methenamine silver stain of skin biopsy specimen, original magnification ×40).
A 2-month regimen of oral voriconazole resolved the cutaneous nodules, but the diarrhea persisted. After treatment was begun with intravenous ganciclovir, the diarrhea improved significantly. There was no recurrence of skin eruption or diarrhea during the 3-month follow-up.
The Emmonsia genus contains 3 species: E parva, E crescens, and E pasteuriana. The first 2 are adiaspiromycosis pathogens in rodents and rarely in humans. In infected tissues, they usually present with distinctive adiaspores.3 To our knowledge, except for 1 case each from Italy1 and Spain,4,5E pasteuriana infection has been limited to HIV-infected patients in South Africa.2 In the present case, negative HIV antibody results and normal lymphocyte counts and humoral immunity were found, while HIV viral load and T-cell function were not evaluated, which is a limitation of our report. The patient’s cachexia and malnutrition, presumed to be from CMV colitis and recent prednisone treatment, likely contributed to her immunosuppression.
Emmonsia pasteuriana is present in infected tissue as intrahistiocytic yeasts. It can be easily mistaken for other fungal infections characterized by the presence of histiocytes with phagocytosed yeast cells, eg, Histoplasma capsulatum and Penicillium marneffei.
The E pasteuriana infection transmission route remains elusive. Our patient developed cutaneous nodules 1 month after close contact with her hamster, and a successful experimental animal model of E pasteuriana infection was constructed only when hamsters were infected via intratesticular innoculation,6 suggesting that contact with hamsters could be an E pasteuriana infection risk factor.
The skin is the most commonly involved organ in E pasteuriana infection.2 Our patient presented only 4 discrete cutaneous nodules, and E pasteuriana was only isolated from skin biopsy specimens. This implies that direct inoculation of E pasteuriana could have caused the cutaneous nodules.
In conclusion, E pasteuriana can infect immunocompromised patients. There is potential risk that more Asian cases may emerge. Further investigation of E pasteuriana geographic distribution and reservoirs would reveal more information.
Corresponding Author: Qian Gao, MD, Department of Dermatology, The First Affiliated Hospital, Sun Yat-sen University, No. 58, Zhongshan 2nd Road, Guangzhou, China, 510080 (firstname.lastname@example.org).
Conflict of Interest Disclosures: None reported.
Published Online: July 22, 2015. doi:10.1001/jamadermatol.2015.1792.
Author Contributions: Drs Tang and Zhou contributed equally to this work.
Additional Contributions: We are indebted to the mycological laboratory staff of Sun Yat-sen University, Sun Yat-sen Memorial Hospital, including Li Yan Xi, MD, PhD; Chang Ming Lu, MD; Sha Lu, MD, PhD; and Ying Hui Liu, MD, without whose invaluable assistance this study could not have been performed. These persons received no payment for their contributions beyond that received in the normal course of their employment.
Tang XH, Zhou H, Zhang XQ, Han JD, Gao Q. Cutaneous Disseminated Emmonsiosis Due to Emmonsia pasteuriana in a Patient With Cytomegalovirus Enteritis. JAMA Dermatol. 2015;151(11):1263-1264. doi:10.1001/jamadermatol.2015.1792