Emmonsiosis
Emmonsiosis, also known as emergomycosis, is a systemic fungal infection that can affect the lungs, generally always affects the skin and can become widespread.[1][2] The lesions in the skin look like small red bumps and patches with a dip, ulcer and dead tissue in the centre.[4]
| Emmonsiosis | |
|---|---|
| Other names | Emergomycosis[1] |
| Specialty | Infectious diseases[2] |
| Symptoms | Skin rash[2] |
| Causes | Emergomyces, previously classified under genus Emmonsia[3] |
| Risk factors | HIV, organ transplant, steroid use.[1] |
| Diagnostic method | skin biopsy, histopathology[1] |
| Differential diagnosis | Histoplasmosis[1] |
| Treatment | Antifungals |
| Medication | Amphotericin B[1] |
| Frequency | Rare[1] |
It is caused by the Emergomyces species, a novel dimorphic fungus, previously classified under the genus Emmonsia.[3] These fungi are found in soil and transmitted by breathing in its spores from the air.[1] Inside the body it converts to yeast-like cells which then cause disease and invade beyond the lungs.[1] Diagnosis is by skin biopsy and its appearance under the microscope.[5] It is difficult to distinguish from histoplasmosis.[3][6] Treatment is usually with amphotericin B.[3]
Emmonsiosis can be fatal.[3] The disseminated type is more prevalent in South Africa, particularly in people with HIV.[3]
Signs and symptoms
Generally, all cases have involvement of the skin.[5] The lesions look like small red bumps and patches with a dip, ulcer and dead tissue in the centre.[4] There may be several lesions and their distribution can be widespread.[1] The lungs may be affected.[3][4]
Cause
It is caused by the Emergomyces species, a novel dimorphic fungus, previously classified under the genus Emmonsia.[3][7] Following a revised taxonomy in 2017 based on DNA sequence analyses, five of these Emmonsia-like fungi have been placed under the separate genus Emergomyces.[3] These include Emergomyces pasteurianus, Emergomyces africanus, Emergomyces canadensis, Emergomyces orientalis and Emergomyces europaeus.[3][8]
Emergomyces africanus was previously known as Emmonsia africanus, which has similar features to Histoplasma spp. and the family of Ajellomycetaceae.[6]
The disease has been observed among people who have a weakened immune system and risk factors include HIV, organ transplant and steroid use.[1][3]
Mechanism
The fungus is found in soil and is released in the air.[1] Transmission is by breathing in fungal spores from the air.[1] Inside the body it converts to yeast-like cells which then cause disease and invade beyond the lungs.[1] In people with HIV, Emmonsiosis has been associated with Immune reconstitution inflammatory syndrome following initiating antiretroviral treatment.[1]
Diagnosis
Diagnosis is by skin biopsy and its appearance under the microscope.[5]
Differential diagnosis
Generally, it is difficult to distinguish from histoplasmosis.[6] Other conditions that appear similar include tuberculosis,[5] blastomycosis, sporotrichosis, chicken pox, Kaposi's sarcoma and drug reactions.[4]
Treatment
Treatment usually includes amphotericin B.[3]
Prognosis
It can be fatal.[5]
Epidemiology
The disseminated type is more prevalent in South Africa, particularly in people with HIV.[5]
History
The disease was thought to be a rare condition of the lung.[2] Early cases may have been misdiagnosed as histoplasmosis.[6]
Other animals
The genus Emmonsia can cause adiaspiromycosis, a lung disease in wild animals.[9]
References
- Schwartz, Ilan S.; Govender, Nelesh P.; Sigler, Lynne; Jiang, Yanping; Maphanga, Tsidiso G.; Toplis, Barbra; Botha, Alfred; Dukik, Karolina; Hoving, J. Claire; Muñoz, Jose F.; Hoog, Sybren de; Cuomo, Christina A.; Colebunders, Robert; Kenyon, Chris (19 September 2019). "Emergomyces: The global rise of new dimorphic fungal pathogens". PLOS Pathogens. 15 (9): e1007977. doi:10.1371/journal.ppat.1007977. ISSN 1553-7374. PMC 6752945. PMID 31536607.
- "ICD-11 - ICD-11 for Mortality and Morbidity Statistics". icd.who.int. Retrieved 28 May 2021.
- Samaddar, Arghadip; Sharma, Anuradha (2021). "Emergomycosis, an Emerging Systemic Mycosis in Immunocompromised Patients: Current Trends and Future Prospects". Frontiers in Medicine. 8: 670731. doi:10.3389/fmed.2021.670731. ISSN 2296-858X. PMC 8104006. PMID 33968970.
- Kutzner, Heinz; Kempf, Werner; Feit, Josef; Sangueza, Omar (2021). "2. Fungal infections". Atlas of Clinical Dermatopathology: Infectious and Parasitic Dermatoses. Hoboken: Wiley Blackwell. p. 102. ISBN 978-1-119-64706-5.
- Schwartz, Ilan S.; Govender, Nelesh P.; Corcoran, Craig; Dlamini, Sipho; Prozesky, Hans; Burton, Rosie; Mendelson, Marc; Taljaard, Jantjie; Lehloenya, Rannakoe; Calligaro, Greg; Colebunders, Robert; Kenyon, Chris (15 September 2015). "Clinical Characteristics, Diagnosis, Management, and Outcomes of Disseminated Emmonsiosis: A Retrospective Case Series". Clinical Infectious Diseases. 61 (6): 1004–1012. doi:10.1093/cid/civ439. ISSN 1537-6591. PMID 26060283.
- Calonje, J. Eduardo; Grayson, Wayne (2020). "18. Infectious diseases of the skin". In Calonje, J. Eduardo; Brenn, Thomas; Lazar, Alexander J.; Billings, Steven D. (eds.). McKee's Pathology of the Skin, 2 Volume Set (5th ed.). Elsevier. pp. 959–960. ISBN 978-0-7020-6983-3.
- Govender, Nelesh P.; Grayson, Wayne (2019). "Emergomycosis (Emergomyces africanus) in Advanced HIV Disease". Dermatopathology. 6 (2): 63–69. doi:10.1159/000495405. ISSN 2296-3529. PMC 6827448. PMID 31700845.
- Jiang, Yanping; Dukik, Karolina; Muñoz, Jose F.; Sigler, Lynne; Schwartz, Ilan S.; Govender, Nelesh P.; Kenyon, Chris; Feng, Peiying; van den Ende, Bert Gerrits; Stielow, J. Benjamin; Stchigel, Alberto M.; Lu, Hongguang; de Hoog, Sybren (1 May 2018). "Phylogeny, ecology and taxonomy of systemic pathogens and their relatives in Ajellomycetaceae (Onygenales): Blastomyces, Emergomyces, Emmonsia, Emmonsiellopsis". Fungal Diversity. 90 (1): 245–291. doi:10.1007/s13225-018-0403-y. hdl:10067/1520590151162165141. ISSN 1878-9129. S2CID 46987097.
- Henry, Ronnie Etymologia: Emmonsia. Emerging Infectious Diseases. 2017;23(2):348. doi:10.3201/eid2302.et2302.