Mycetoma
Mycetoma is a term for a chronic subcutaneous infection caused by aerobic actinomycetic bacteria (actinomycetoma) or fungi (eumycetoma).[1] While most cases of mycetoma occur in Sudan, Venezuela, Mexico, and India, its true prevalence and indicence are not well-known.[1][2] It appears most frequently in people living in rural areas, particularly farmers and shepards.[3] It is listed by the World Health Organization (WHO) as a neglected tropical disease.[2]
Pathogenesis
Mycetoma is caused by common saprotrophs found in the soil and on thorny shrubs in semi-desert climates.[4] The most common causative agents are:
- Madurella mycetomatis (fungus)
- Nocardia brasiliensis (bacteria)
- Actinomadure madura (bacteria)
- Streptomyces somaliensis (bacteria)
- Actinomadura pelletieri (bacteria)[2]
Infection is caused as a result of localized skin trauma, such as stepping on a needle or wood splinter, or through a pre-existing wound.[4]
The first visible symptom of mycetoma is a typically painless swelling beneath the skin; over several years, this will grow to a nodule (lump).[3] Affected people will experience massive swelling and hardening of the area, in addition to skin rupture and the formation of sinus tracts that discharge pus and grains filled with organisms.[3] In many instances, the underlying bone is affected.[4] Some people with mycetoma will not experience pain or discomfort, while others will report itching and/or pain.[3]
Risk
Frequent exposure to penetrating wounds by thorns or splinters is a risk factor.[3] This risk can be reduced by disinfecting wounds and wearing shoes.[4]
Diagnosis
There are currently no rapid diagnostic tools for mycetoma.[2] Mycetoma is diagnosed through microscopic examination of the grains in the nodule and by analysis of cultures.[4] Since the bacterial form and the fungal form of mycetoma share similar features, diagnosis can be a challenge.[1]
Treatment
While treatment will vary depending on the cause of the condition, it may include antibiotics or antifungal medication.[3] Actinomycetoma, the bacterial form, can be cured with antibiotics.[1] Eumycetoma, the fungal form, is treated with antifungals and surgery.[4][1] For both forms, extended treatment is necessary.[1]
In cats, mycetoma can be treated with complete surgical removal. Antifungal drugs are rarely effective.[5]
Research
For a list of trials that are related to mycetoma, go to this ClinicalTrials.gov link: https://www.clinicaltrials.gov/ct2/results?cond=%22Mycetoma%22
Additional Resources
- DermNet NZ: an online resource about skin diseases from the New Zealand Dermatological Society Incorporated.
- Merck Manual: a resource designed for healthcare professionals
- Monarch Initiative: a set of tools designed to bring together data from humans and other species and make it easier to compare signs and symptoms of different diseases.
- Orphanet: a reference portal from Europe that provides information on rare diseases and orphan drugs.
References
- ^ a b c d e f Welsh O, Al-Abdely HM, Salinas-Carmona MC, Fahal AH (October 2014). "Mycetoma medical therapy". PLoS Neglected Tropical Diseases. 8 (10): e3218. doi:10.1371/journal.pntd.0003218. PMC 4199551. PMID 25330342.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ a b c d van de Sande WW, Maghoub El S, Fahal AH, Goodfellow M, Welsh O, Zijlstra E (March 2014). "The mycetoma knowledge gap: identification of research priorities". PLoS Neglected Tropical Diseases. 8 (3): e2667. doi:10.1371/journal.pntd.0002667. PMC 3967943. PMID 24675533.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ a b c d e f "Mycetoma". Genetic and Rare Diseases Information Center (GARD). National Institutes of Health. Retrieved 2018-04-17.
- ^ a b c d e f RESERVED, INSERM US14 -- ALL RIGHTS. "Orphanet: Mycetoma". www.orpha.net. Retrieved 2018-04-17.
{{cite web}}: CS1 maint: numeric names: authors list (link) - ^ Eldredge, Debra M.; Carlson, Delbert G.; Carlson, Liisa D.; Giffin, James M. (2008). Cat Owner's Home Veterinary Handbook. Howell Book House. p. 160.