Tropical Fungal Diseases Flashcards
(39 cards)
What is Mycetoma?
An infection that can be either fungal or bacterial, which causes a slow insidious destruction of skin, soft tissue and bones and nodular masses with sinus and ‘grain’ formation
What is the epidemiology of Mycetoma?
Europe, Asia, Africa, Latin America
**MEXICO AND SUDAN
Associated with areas of long dry season
Associated with thorny bushes –> people who spend their time working outside are most at risk
What causes Mycetoma?
BACTERIA –> actinomyocytes, like nocardia spp.
FUNGAL –> Madurella spp.
How does Mycetoma present?
A painless slow growing nodule, usually on the foot, which eventually spreads along the skin and soft tissue and causes the formation of sinuses
What are the complications of Mycetoma?
- Disseminated infection –> amputation, death etc.
**Very insidious onset which means people are very slow to present with it
How is mycetoma diagnosed?
FNA and microscopy
PCR
Clinical diagnosis
Relevant imaging looking for bony destruction
How is mycetoma managed?
- Bacterial –> Co-trimoxazole + Streptomycin
- Fungal –> Ketoconazole 400mg OD for 1-2 years
What is a major side effect of long-term anti-fungal use?
Hepatic toxicity
What is Sporotrichosis?
A fungal sub-cut infection which frequently infects and spreads along lymph nodes
Found in SA
Associated with HIV
Rx with Antifungals
What is histoplasmosis?
Fungal infection primarily assocaited with HIV, which behaves very similarly to TB
What is the epidemiology of Histoplasmosis?
North America, South America, Africa
French Guiana (exam!) –> leading cause of HIV deaths
What is the main risk factor for developing histoplasmosis?
HIV +ve
What is the causative organism of histoplasmosis?
Histoplasma Capsulatum
2 varieties: African and Classical
How does Histoplasmosis present?
95% Asymptomatic
Acute infection: Fever, cough, malaise, lymphadopathy
Progressively worsens –> unrelenting pneumonia, weight loss, night sweats, hepatomegaly
How is histoplasmosis diagnosed?
- CXR
- Aspirate (Bone Marrow or Liver) –> microscpoy and culture
- Antigen testing
What might you see on a histoplasmosis x-ray?
Cavitating areas
Apical Lesions
Miliary Pattern
(i.e. TB es el mismo)
What is your main DDx of histoplasmosis?
TB
How do you manage Histoplasmosis?
- Liposomal Amphotericin B is recommended in disseminated illness
Itraconazole if non-severe disease (i.e. no end organ involvement, such as O2 requirement, renal impairment, hepatic failure)
What is paracoccidiomycosis?
Paracoccidioidomycosis is a granulomatous systemic infection caused by the fungus Paracoccidioides.
This fungus lives in parts of Central and South America.
Most often affects men who work outdoors in rural areas.
What is Talaromycosis?
An invasive fungal disease which predominantly occurs in Asia and affects HIV +ve people
How does Talaromycosis present?
Diffuse papular skin lesions with necrotic centre
How do you treat Talaromycosis?
Amphotericin B or L-AMB
NOT A QUESTION JUST AN IMPORTANT FACT:
Basically with the fungal infections - chuck them into your DDx whenever you have an HIV +ve patient with some weird systemic disease and rash
Testing is through Antigen testing usually
Management is usually long term
Differentiate these by their location more than anything (because for example, talaromycosis, histomplasmosis and paracoccidiomycosis present almost the same, but have different global epidemiology)
What are the side effects of Amphotericin B?
Highly toxic
Renal toxicity
Anaemia
Rigors
Needs to be given IV - challenging for long courses of medication
