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==Cryptococcosis==
==Cryptococcosis==
*Over 19 species
**''C. neoformans'' only major pathogen
*Worldwide
*Occurs in high concentrations in pigeon droppings (high creatinine concentration)
**The pigeon is not infected
**''C. neoformis'' colonise the droppings after they have been excreted
**Also found in fruit, milk and soil
*Exogenous, inhaled infection which is generally sporadic (non-contageous)
**Can also be absorbed via skin penetration and ingestion
*May be a primary pathogen or opportunistic
*Targets the respiratory system
**Including the paranasal sinuses
**Also can be systemic, cutaneous, visceral, skeletal or ocular
*Causes sporadic mastitis in cattle
**Can spread within the herd
*Affects the CNS of dogs and cats
**Paranasal sinuses and pharynx can be infected with dissemination to the CNS and other tissues
***E.g. Lungs, kidneys and joints
**Also causes subcutaneous granulomas
**The tip of the nose is a common site of infection in cats
*Causes myxoma-like lesions of the lung and lip in horses
*Causes cryptococcal meningitis in humans
*Also affects dolphins, foxes, ferrets, monkeys, birds, cheetahs and guinea-pigs
*Large yeast with capsule seen using India ink stain
*Stains with PAS (Periodic acis Schiff)
*Gram positive
*Grows on blood agar and Sabouraud's Dextrose agar forming white, granular colonies which become slimy, mucoid and turn cream/brown within a week
*Species identified by carbohydrate assimilation tests
*Antigen and antibody should be tested for as antibody formed by the body is soon overwhelmed and neutralised by abundent polysaccharide antigen from the capsule, in active, systemic infections
**Latex agglutination for antigen, complement fixation, ELISA and IFAT can be used
==Geotrichosis==
==Geotrichosis==