Mycetoma and Its Clinical Features

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Questions and Answers

What is the primary reason mycetoma is often described as painless?

It primarily affects internal organs.

Nerves and tendons are preserved during infection. (correct)

The symptoms appear suddenly and dramatically.

It leads to immediate tissue necrosis.

Which site is most commonly affected by mycetoma?

Lower limbs (correct)

Internal organs

Upper limbs

Head

How is mycetoma typically diagnosed in superficial bone lesions?

By clinical symptoms observed during treatment.

Through blood tests indicating infection levels.

Accidental findings during X-ray or surgery. (correct)

Following a biopsy of the affected tissue.

What pathology is associated with advanced mycetoma cases?

Multiple abscesses and cavitary lesions. Signup and view all the answers

What distinguishes Actinomycetoma from Eumycetoma in radiological findings?

Smaller and more abundant cavities. Signup and view all the answers

What is a common outcome of the spread of mycetoma destruction?

Formation of sinuses and fistulas. Signup and view all the answers

Which population is more likely to experience internal organ infection due to mycetoma?

Immunocompromised patients. Signup and view all the answers

What duration is typical for the development of mycetoma before presentation?

3 months to 30 years. Signup and view all the answers

What factor does NOT influence the clinical picture of mycetoma?

Dietary habits of the host Signup and view all the answers

Which characteristic is associated with Eumycetoma?

Localized with well-defined margins Signup and view all the answers

What is a correct statement regarding how mycetoma of the head and neck can affect the patient?

It may cause neurological symptoms due to pressure on the brain. Signup and view all the answers

Which soft tissue tumor is NOT typically included in the differential diagnosis of mycetoma?

Rhabdomyosarcoma Signup and view all the answers

What indicates the likelihood of tuberculosis when examining mycetoma?

Bone destruction in absence of sinuses Signup and view all the answers

What is the standard treatment regimen for Actinomycetoma?

Streptomycin and Cotrimoxazole Signup and view all the answers

Which medication is the drug of choice for Eumycetoma?

Ketoconazole Signup and view all the answers

What is the recommended duration of liver function testing during Eumycetoma treatment?

Every month Signup and view all the answers

In advanced cases of mycetoma that do not respond to medical treatment, what is the common surgical intervention?

Amputation Signup and view all the answers

What is a significant reason for performing medical treatment before surgery in mycetoma cases?

To prevent local spread of organisms Signup and view all the answers

What percentage range indicates the amputation rate for advanced mycetoma cases in Sudan?

25 – 50% Signup and view all the answers

Why is a margin of healthy tissue recommended to be excised with Actinomycetoma lesions?

Due to ill-defined borders of the lesion Signup and view all the answers

What is a notable characteristic of the recurrence rate with surgical treatment for mycetoma?

It ranges between 20% and 90% Signup and view all the answers

Which of the following characteristics correctly describe Mycetoma?

It causes destructive granulomatous responses. Signup and view all the answers

What is a significant factor in the geographical distribution of Mycetoma?

It is common in areas with savanna vegetation. Signup and view all the answers

What is the primary organism responsible for Eumycetoma in Sudan?

Madurella mycetomatis Signup and view all the answers

What type of grains does Streptomyces somaliensis produce in Actinomycetoma?

Small hard yellow grains Signup and view all the answers

At what latitudes is Mycetoma most commonly found?

15° – 30° N Signup and view all the answers

What is the gender ratio for Mycetoma prevalence in affected populations?

5:1 Signup and view all the answers

Which of the following statements is true regarding the affected age group of Mycetoma?

It can affect any age group, but is common in ages 15 – 45 years. Signup and view all the answers

How does Mycetoma typically start in the body?

By direct penetration of a thorn contaminated with the organism. Signup and view all the answers

Which condition must be differentiated from primary osseous mycetoma?

Chronic osteomyelitis Signup and view all the answers

In collecting grains for diagnosis, what should be analyzed during macroscopic examination?

Shape and size Signup and view all the answers

What characteristic is most likely observed in the swelling of mycetoma during examination?

Firm, rounded, and potentially soft Signup and view all the answers

What is a key difference in cavity characteristics between eumycetoma and other types in X-ray findings?

Eumycetoma shows abundant small cavities Signup and view all the answers

What type of culture media is used for Actinomycetoma?

LJ media containing eggs Signup and view all the answers

Which factor is important for effective management of mycetoma to avoid high recurrence rates?

Incorporating medical treatment Signup and view all the answers

What aspect of patient history is crucial for assessing mycetoma?

Type of occupation and history of similar conditions Signup and view all the answers

What is the approximate number of new mycetoma cases seen in hospitals in Sudan each year?

Approximately 400 Signup and view all the answers

Study Notes

Mycetoma Overview

Mycetoma is a chronic, localized subcutaneous infection that slowly progresses and is relatively painless.
It involves destructive granulomatous and suppurative responses.
The disease is caused by either Actinomycetes (Actinomycetoma) or true fungi (Eumycetoma).

Historical Background

Initially reported from India 300 years ago.
Initially called "Madura foot," as the foot was the most common infection site.
The preferred name "Mycetoma" was introduced in 1861 to differentiate it from other tumors.

Causative Agents

A. Eumycetoma*
More common in Sudan.
Madurella mycetomatis: Forms black, hard, large grains, a very difficult type to treat. Responsible for approximately 70% of cases in Sudan.
Curvularia lunata: Less frequent but produces black grains.
Aspergillus nidulans: Produces white, soft, large grains.
B. Actinomycetoma*
Caused by bacteria.
Streptomyces somaliensis: Forms small, hard yellow grains (sandy grains).
Actinomadura madurae: Forms large, white, soft grains similar to Aspergillus.
Actinomadura Pelletieri: Forms very small red grains.
Nocardia braziliensis: Forms white or creamy grains.

Epidemiology

Common in tropical and subtropical regions.
Typically found in latitudes 15° - 30° N (Mycetoma belt).
The climate and acacia plants with thorns favor the disease.
Influences of prevalence include temperature, rainfall, and soil type.

Relation to Sex, Age & Occupation

Males are more affected than females (ratio 5:1), potentially due to genetic factors and outdoor activities.
Commonly seen in people aged 15-45 (earning age).
Occupations with frequent contact with soil, such as farmers, wood-cutters, and diggers, are at higher risk.

Pathogenesis & Pathology

Begins in subcutaneous tissue, following thorn penetration with contaminated organisms.
Organisms form colonies (grains).
The body's immune response forms a granuloma.
Initial stages present as small subcutaneous swellings, that gradually increase in size (can be hard or soft).
Eventually the skin fixes to the granuloma and sinuses discharge pus and grains. Spreading may extend to muscles and bones, but nerves and tendons are spared (hence painless).
Bone destruction occurs, replaced with grains.
Generally localized, but can affect various body parts, including limbs, head, neck, chest, back, abdomen, and perineum. Internal organs are rarely affected unless immunocompromised.
Grains in infected tissues are typically compact, up to 5 mm in diameter.

Clinical Manifestations

Duration may vary from 3 months to 30 years.
Presentation is often late due to the painless nature of the disease and lack of health education surrounding it.
Clinical manifestations are similar for both types of mycetoma . However, Actinomycetoma generally progresses more rapidly.

Radiological Examination

X-rays reveal cavities—generally small and numerous in Actinomycetoma; larger and less abundant in Eumycetoma.

Differential Diagnosis

Mycetoma is differentiated from various soft tissue tumors (Kaposi's sarcoma, neurofibroma, malignant melanoma, fibrolipoma, thorn granuloma), as well as tuberculosis and osteogenic sarcoma. It requires differentiating from other bone conditions, like chronic osteomyelitis, osteoclastoma, and bone cysts.

Lab Diagnosis

Collection of grains: Microscopic analysis of grain characteristics (size, shape, color).
Direct Microscopy: Examination of crushed grains for characteristics (hyphae in Eumycetoma).
Culture: Growing microorganisms on specialized media (blood agar, LJ media – rich media containing eggs).

Treatment

A) Medical Treatment: Combined treatment often required
Actinomycetoma: Often a combination of Streptomycin(first month, alternating days thereafter) and Cotrimoxazole or alternatives like Dapsone, Rifambicin, or Fansidar, potentially with amikacin (for non-responsive cases). Duration of cotrimoxazole approximately 5 weeks
Eumycetoma: Ketoconazole is preferred; or procaine penicillin IM.
B) Surgical Treatment: Ranges from local excision to amputation of affected parts. Surgery may also be used for diagnoses and removal of affected tissues. Used for localized areas or massive lesions.

Prevention

Health education, particularly for farmers and those in contact with soil, encompassing the use of personal protective equipment (gloves and boots).
Early diagnosis:
Early treatment.

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Description

This quiz explores the key characteristics and clinical aspects of mycetoma, including its painless nature, common sites of infection, and diagnostic methods. Additionally, it delves into differences between Actinomycetoma and Eumycetoma, treatment options, and associated pathologies. Test your knowledge on this tropical disease and its implications.