Mycetoma

Subcutaneous Mycoses
(Mycetoma)
General Introduction
Types of Mycetoma and Causative agent
Pathogenesis
Clinical manifestation
Laboratory Diagnosis
Specimen Collection
Direct Examination
Culture
Indetification
Treatment

1. SUBCUTANEOUS MYCOSES (MYCETOMA) Ankur Vashishtha Assistant Professor IIMT University, Meerut

2. SUBCUTANEOUS MYCOSES The agents of subcutaneous mycoses usually inhabit the soil. They enter the skin by traumatic inoculation with contaminated material and tend to produce the granulomatous lesions in the subcutaneous tissue.

3. MYCETOMA Mycetoma is a chronic, slowly progressive granulomatous infection of the skin and subcutaneous tissues. Clinically, it is manifested as a triad of swelling, discharging sinuses and presence of granules in the discharge Mycetoma is also known as Maduramycosis or Madura foot , as it was first described in Madurai, South India, by John Gill (1842).

4. Types of Mycetoma and Causative Agents Mycetoma can be of two types. It can be caused by either fungal agents ( eumycetoma ) or bacterial agents ( actinomycetoma ). Eumycetoma A ctinomycetoma

5. Agents of Mycetoma and types of grains they produce Eumycetoma (Fungal agent) Actinomycetoma (Bacterial agent) Black granules Madurella mycetomatis Madurella grisea Exophiala jeanselmei Curvularia species White to yellow Granules Nocardia species Streptomyces somaliensis Antinomadura madural White Granules Pseuallesceria bydii Aspergillus nidulans Acremonium species Fusarium sopecies Pink to red Geanules Actinomadura pelletieri

6. Pathogenesis The causative agents enter the skin or subcutaneous tissue from the contaminated soil, usually by the accidental trauma such as thorn prick or splinter injury.

7. Clinical Manifestations Hallmark of mycetoma is presence of clinical triad consisting of:- Tumor like swelling, i.e. tumefaction Discharging sinuses Discharge oozing from sinuses containing granules.

8. Epidemiology Mycetoma is endemic in Africa, India, the Central and South America, and has a non-uniform distribution. Overall, actinomycetoma is more common ( 60%) than eumycetoma (40%) globally, whereas eumycetoma is more common in Africa However , within a country,

9. Laboratory Diagnosis Specimen Collection The lesions should be cleaned with antiseptics and the grains should be collected on sterile gauze by pressing the sinuses from periphery or by using a loop.

10. Direct Examination Granules are thoroughly washed in sterile saline; crushed between the slides and examined. Macroscopic appearance of granules such as color, size, shape , texture may provide important clue to identify the etiological agent

11. If eumycetoma is suspected : Grains are subjected to KOH mount, which reveals hyphae of2- 6 μm width along with chlamydospores at margin If actinomycetoma is suspected : Grains are subjected to Gram staining which reveals filamentous grampositive bacilli (0.5-1 μm wide). Modified acid fast stain is performed if Nocardia is suspected, as it is partially acid fast

12. Histopathological staining H & E Satin PAS GMS

13. Culture For fungal SDA and Bacteriological such Lowenstein Jensen media. For fungal:- Inoculated on SDA with antibiotics like chloramphenicol and gentamicin, and incubated at 25°C, 37 ° C and 44°C. For bacterial:- Inoculate on Blood agar, LJ and SDA tubes.

14. IDENTIFICATION For Eumycetoma (Fungal agent) For Actinomycetoma (Bacterial agent) Observation of the growth rate Growth rate Colony Morphology Colony Morphology Production of Candida Urease test Sugar assimilation patterns Tyrosine test

15. Treatment Treatment of mycetoma consists of surgical removal of the lesion followed by use of: Antifungal agents for eumycetoma ( I traconazole or amphotericin B for 8-24 months ). Antibiotics for actinomycetoma such as ( amikacin plus cotrimoxazole ).

16. Thank You