This presentation offers a concise yet comprehensive exploration of Eumycetoma, a rare and complex fungal infection. Delve into its origins, clinical manifestations, and contemporary treatment approaches. An invaluable resource for healthcare professionals and enthusiasts keen on understanding and addressing this intriguing medical condition.
3. WHAT IS MYCETOMA ?
⮚ Mycetoma is a chronic granulomatous, progressive inflammatory disease
that involves the subcutaneous tissue after a traumatic inoculation of the
causative organism
⮚ 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
4. HISTORY
▪ The first reference to mycetoma dates from the Byzantine period (300-600
A.D.), with evidence from an adult skeleton whose morphological bone
structure was suggestive of a mycetoma infection
▪ First written account was found in an ancient Indian religious book, Atharva
Veda, where it was mentioned as “Anthill foot“
▪ First described in Madras, South India, by a French missionary John Gill in
1842 naming it "Madura foot"
5. EPIDEMIOLOGY
• Mycetoma is found worldwide, but endemic in tropical and subtropical countries,
mostly between the latitudes 15° south and 30° north, called “mycetoma belt”
• The endemic areas are characterized by short rainy seasons with little daily
temperature fluctuations, followed by long dry seasons with broad daily
temperature fluctuations (45-60°C to 15-18°C)
• Actinomycetoma is more prevalent in drier areas and eumycetoma in humid areas
• Male are prone to infection due to exposure to field work
6. ▪ In 1913, Pinoy observed that the disease was caused by two etiologic agents
and divided the disease into two categories:
1. Actinomycetoma (bacterial agents) and
2. Eumycetoma (fungal agents)
CLASSIFICATION
8. 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
• Feet are the most common site affected, although any site can be involved
• May be involvement of underlying fasciae and bones, producing osteolytic or
osteosclerotic bony lesions
9. EUMYCETOMA ORGANISMS
▪ Most of the agents causing eumycetoma are saprotrophic environmental fungus
▪ Taxonomically these fungi are members of either Deuteromycetes or Ascomycetes
▪ About 25 fungal species causing eumycetoma
▪ Produce two types of grains: Black and White
A. Black Grain Eumycetoma:
✔ Madurella mycetomatis
✔ Madurella grisea
✔ Exophiala jeanselmei
✔ Curvularia geniculata
B. White Grain Eumycetoma:
✔ Pseudallescheria boydii
✔ Aspergillus nidulans
✔ Acremonium falciforme
✔ Fusarium species
10. PATHOGENESIS
⮚No known vector or animal reservoir
⮚The disease most likely initiates after a minor trauma that
inoculates the causative microorganism in the subcutaneous tissue
⮚After inoculation of the causative agent, a subcutaneous infection
develops
⮚The is usually painless and processes slowly, over months and years
11. PATHOGENESIS CONTD…
Painless subcutaneous firm nodule
observed
Trauma of skin
Massive swelling with skin rupture, and sinus tract
formation
Old sinuses close and new ones open, draining exudates
with grains. Grains may sometimes be seen with naked eye
12. LABORATORY DIAGNOSIS
❖ Diagnosis of mycetoma is based on clinical presentation and identification of the
etiologic agents
❖ Detailed and proper history about occupation, trauma , geographical area of the
patient is valuable in diagnosis
❖ The most specific diagnostic tool is the examination of the grains discharged
from sinuses
13. SPECIMEN COLLECTION
✔ Clinical sample is usually grains or granules
✔ Pus , exudates or biopsy may also be taken
✔ 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
✔ The samples can be obtained from any open sinus or by deep surgical
biopsy
14. FINE-NEEDLE ASPIRATION CYTOLOGY
• Fine-needle aspiration cytology (FNAC) with
cell blocks is also used for specimen collection
• In this technique, a needle attached to a
syringe is inserted into the suspected
mycetoma lesion and aspirated under negative
pressure
• It should be performed in at least 3 different
directions
Figure: Fine-needle aspiration cytology
collection technique
15. 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
• Grains contain fungi in KOH wet mount or on histopathological examination
16. MACROSCOPIC APPEARANCE
• Madurella mycetomatis has black, big grains of 5mm or
more. Initially, colonies are yellow or brown with a
ridged surface and are frequently covered by a short
aerial gray mycelium
• Madurella grisea has black, oval or irregularly shaped
grains that measure ≥ 1-2mm
• Scedosporium apiospermum has hyaline white grains
measuring 2-4 mm in diameter that vary in shape.
Grains are soft and have septate hyphae and
chlamydospores
Madurella mycetomatis
Scedosporium apiospermum
17. Figure: Surgical biopsy showing a well-encapsulated eumycetoma lesion
with numerous black grains
18. MICROSCOPY
❖KOH Preparation:
• Add few drops of KOH and grains on glass slide
• Put coverslip
• Crush gently by applying pressure over coverslip with glass rod or handle of loop
• Leave the wet mount for few hours in petridish with moist filter paper
• Examine under microscope to look for characteristic hyphae
⮚ Grains are subjected to KOH mount, which reveals hyphae of 2–6 μm width along with
chlamydospores at margin
19. Figure: KOH wet mount direct microscopic examination of M.
mycetomatis grains showing its hyphal structure
20. HISTOPATHOLOGICAL STAINING
• Tissue sections stained with Hematoxylin & Eosin staining (H&E) and
by special staining techniques, such as the Periodic-acid-Schiff (PAS)
and Grocott-Gomori silver staining
• It reveals distinct cytological features, characterized by the presence
of suppurative granulomas surrounding the characteristic grains of
the causative organism
22. CULTURE
• Granules obtained from deep biopsies are the best specimen for culture as they
contain live organisms
• The eumycetes culture must contain antibiotics
• Sabouraud’s dextrose agar media supplemented with antibiotics eg. penicillin G
(20 U/ml), gentamicin sulphate (400 μg/ml), streptomycin (40 μg/ml), or
chloramphenicol (50 μg/ml) used for culture
23. CULTURE CONTD…
• Washed and crushed granules are inoculated in several tube of SDA media
• The media incubated in 25°C and 37°C temperature
24. COLONY
▪ M. mycetomatis:
✔ Grows in Optimum temp. 37°
✔ valvatid or powdery. Usually cream color
✔ Diffuse brown pigment present
▪ M. grisea:
✔ Better grow at normal temperature
✔ Dark leathery, folded colony
▪ Acremnium falciforne:
✔ White colony with diffuse violet pigment
Figure: M. mycetomatis
growth in SDA media
25. SERODIAGNOSIS
• The tests are:
✔ Immunodiffusion
✔ Indirect hemagglutination assays
✔ ELISA etc.
• Serological assays have been developed only for M. mycetomatis and
Pseudallescheria boydii
• For P. boydii, both an ID (Immunodiffusion) assay with crude antigens and an IHA
(indirect hemagglutination assays) were developed
26. MOLECULAR-BASED IDENTIFICATION METHODS
❖ PCR
• The technique based on the identification of the internal transcribed spacer (ITS)
• In order to identify all fungal mycetoma causative agents, the ITS regions are
usually amplified with pan-fungal
• primers and sequenced
• Identification is based on comparing the resulting sequence with sequences
already present in GenBank
28. TREATMENT
• Management of mycetoma is highly challenging for the clinicians
• Many drugs have been tried with variable results
• Oral Ketoconazole 200mg twice daily and Itraconazole 100mg twice
daily for 8-24 months
• Amphotericin B is recommended for Madurella and Fusarium species
29. DIFFERENCE BETWEEN EUMYCETOMA AND
ACTINOMYCETOMA
Clinical
manifestations
Eumycetoma Actinomycetoma
Tumor Single,
well-defined margins
Multiple tumor masses,
ill-defined margins
Sinuses Appear late,
few in number
Appear early,
numerous with raised inflamed opening
Discharge Serous Purulent
Grains Black/White White/Red
Bone Osteosclerotic lesions Osteolytic lesions
Grains contain Fungal hyphae
(> 2 um)
Filamentous bacteria
(< 2 um)
30. QUESTIONS?
1. What is Eumycetoma?
2. What are the etiological agents for eumycetomas?
3. Difference between Eumycetoma and actinomycetoma?
4. How to prepare grains sample for microscopic examination?