Questions about Dropsy

[BlueLineAquaticsSC]

To preface, none of my fish, currently or previously, have dropsy, but I saw someone asking about it in the Coop FB group and it got me curious. Dropsy isn’t the disease, but rather a symptom right? It’s when fluid builds up in the body cavity. Every time I hear people talk about dropsy the general consensus is the fish is as good as dead. So is it the dropsy that kills the fish or is it that if your fish has dropsy the underlying issues have reached terminal levels? Anyone ever have a method with a generally good success rate for treatment, I’ve always wondered if lancing the area and draining the fluid build up would work.

[Guppysnail]

My understanding from everything I’ve read over the years is the retention of fluid that is called dropsy is kidney and gill failure. 
The kidneys and gills function to continuously push water out as water is constantly pushing into the fish. Once they no longer function you see the bloating and pine coning.
So many things bacterial, viral, parasitic, environmental toxins or injury can cause damage to  and failure of the kidneys and gills. That’s why treating just based on the ballooning symptom is not affective. The kidneys and gills are already damaged and failing and the ballooning itself is never the root cause of the illness and rarely heal once damaged that far. 
This is just what I know from reading tons of stuff over the years. I have never seen a fish recover permanently even if I get the pine cone ballooning down temporarily. 
Hope that helps.