DOG VALLEY FEVER?

Tavishi

ihardlyknowher

As some of you might know, I've been falling further and further and further into the pharmacology and pathology rabbit holes. I'm stuck. Someone get me out. My clinic work has also not been improving this, as I've just been spending all my free time looking at the drug cabinets.

The treatment of valley fever is pretty cool to me; valley fever just eludes all common diagnostic procedures.

Valley fever is a fungal infection, caused by infection by Coccidioides spp. (generally C. immitis and posadasii.) The fungi are generally brought into the body by dust storms. When wind makes the soil go brr, so too does the fungi go brr, thus causing valley fever. Both C. immitis and C. posadasii are found in Arizona, one of the hotspots of valley fever. Case in point: Wednesday's dust storm...

NOT tuff!!!

While humans also get valley fever, dogs are cool, so I choose to discuss them. Now, valley fever primarily is a respiratory disease, thus causing symptoms like persistent coughing, hacking, and wheezing. However, most cases include dissemination of symptoms that might set this apart from a regular upper respiratory infection.

Some of the characteristic symptoms of valley fever are the aforementioned URI symptoms, lethary, anorexia, tachypnea (fast breathing), and more. When the disease disseminates however, it can cause a wide variety of problems, from seizures to abnormal ocular discharge.

this sea lion, Wafer, was rescued in 2020 and diagnosed with valley fever

There is no way to diagnose valley fever without some specific tests looking for evidence of the Evil fungus. In the southwest, any enlarged lymph nodes, even without clinical signs, warrant tests for valley fever. With no history of valley fever, a generally reliable test is a serum antibody test; essentially, looking to see if the body is trying to defend against coccidioidomycosis. This test is called AGID, or antibody agar gel immunodiffusion. Around four weeks after initial infection, AGID tests will appear positive.

Additionally, histopathological examination quite literally just looks for the fungi in the body. This can also backfire and not necessarily be super useful, as fungi might be missed. However, it rarely has false positive tests.

big circle thing with granules is a coccidioidomycosis spherule

When neurological symptoms, like seizures, are present, sampling and testing of CSF for Coccidioides spp. is very useful. Example tests used to diagnose include MRI (looking for the intracranial lesions) and EIA (enzyme immunoassay) tests.

valley veterinary neurology!!! whooo go az

After diagnosis, we resort to antifungals to solve the issue. Now, valley fever varies in severity of disease. While some cases can be fatal, some are nothing more than a cold. If you live in Arizona, you've almost certainly heard about one of your friends getting valley fever: it's no different than ringworm in moist places.

The most common antifungal medications used to treat valley fever are fluconazole and itraconazole. Fluconazole, is, however, more commonly used than itracconazole, because it has fewer known adverse side effects. However, both belong to the same drug class, and both are imidazoles.

fluconazole! ! !

Fluconazole works like most azole drugs: making the cell membranes of the fungi more permeable. It inhibits the fungal cytochrome P450 enzyme 14α-demethylase, which converts lanosterol to ergosterol. As a result, ergosterol isn't produced, a key component of the cell wall of the fungi.

bottom half of graphic!

ok bye bye for now :p