Crypto in cats refers to two different parasitic infections: Cryptosporidiosis and Cryptococcosis. Cryptosporidiosis is caused by the ingestion of the Cryptosporidium parasite through contaminated water, food, or feces. Symptoms include diarrhea, fever, and lack of appetite. Cryptococcosis, on the other hand, is caused by the inhalation of the fungal spores of the Cryptococcus neoformans or Cryptococcus gattii species complex, which are commonly found in bird droppings and decaying vegetation. Symptoms of cryptococcosis in cats can include non-painful, non-itchy nodules on or below the skin, lymph node enlargement, lethargy, and anorexia.

It is important to note that while both infections have "crypto" in their names, they are caused by different organisms and have different symptoms and treatments. Cryptosporidiosis is treated with supportive care, such as fluid therapy and electrolyte replacement, while Cryptococcosis is treated with antifungal medications. Diagnosis of Cryptosporidiosis can be done through a fecal examination, while Cryptococcosis can be diagnosed through an antigen detection test.