Nodules (Marsella) Flashcards
1
Q
Nodules
A
Solid elevations that extend deep into the dermal or subcutaneous tissue (inflammatory or neoplastic)
2
Q
DDX for nodules: Fungal
A
- Cryptococcus
- Histoplasma
- Coccidiodomycosis
- Sporotrichosis
- Kerion
- Mycetoma/pseudomycetoma
- Phaeohyphomycosis
- Oomyces (pythiosis)
3
Q
DDX for nodules: Bacterial
A
- Deep pyoderma
- Acral lick dermatitis
- Cutaneous bacteral granuloma
- Botryomycosis
- Abscess
- Staphylococcus furunculosis
- Opportunistic/atypical mycobacteria
- Actinomyces
- Actinobacillus
- Leprosy
4
Q
DDX for nodules: non-infectious/sterile
A
- Allergy (cats)
- Eosinophilic granuloma
- Mosquito hypersensitivity
- Sterile nodular panniculitis
- Sterile nodular granuloma/pyogranuloma
- Plasma cell pododermatitis (cats)
- Neoplastic
5
Q
Nodule diagnostic approach
A
- FNA
- Biopsy for histopath & culture
- R/O other infectious causes
6
Q
Systemic fungal infections
A
- Cryptococcosis
- Histoplasmosis
- Blastomycosis
- Coccidiodomycosis
7
Q
Subcutaneous fungal infections
A
- Sporotrichosis
- Phaeohyphomycosis
- Mycetoma
- Kerion
8
Q
Sporotrichosis (general info)
A
- Sporothrix schenckii
- Thermally dipmorphic (yeast in tissues)
- In soils and decaying organic matter
- Spread by inoculation (contaminate wound) or inhalation (rare)
- ZOONOTIC
9
Q
Infection of sporotrichosis from cats (to humans)
A
- Large number of organisms in feline exudate
- No immune suppression necessary
- Wear gloves
- Wash hands in chlorohexidine and povidone iodine
10
Q
Feline sporotrichosis
A
- Draining nodules (head, distal limb, tail)
- Hx of poor response to abx
- Autoinoculation in other parts by grooming
- Most cats develop disseminated dz
11
Q
Sporotrichosis diagnosis
A
Easiery in cats due to large number of organisms
- Cytology
- Culture
- Histopath
12
Q
Sporotrichosis treatment
A
- Itraconazole
- Ketoconazole
- Iodides
- Treat at least 1 month past resolution of clinical signs
13
Q
Iodism
A
- Oral iodine treatment not tolerated well
- Vomit, anorexia, depression
- Twitching, hypothermia
- Ocular & nasal discharge
- Dry coat, excessive scaling
14
Q
Kerion
A
- Exudative nodular lesions
- Reaction to dermatophytic infection
- M. gypseum
- T. mentagrophytes
- Furunculosis
(Dermatophytes don’t like to be in dermis, usually die and act as foreign body)
15
Q
Dermatophytic psuedomycetoma
A
- Subcutaneous nodules
- Most common on trunk
- Frequent ulceration
- M. canis
- Persian cats
- Histopath - pyogranulomatous dermatitis w/ fungal hyphae, tissue grains