Hypervolemia, not cardiac failure, cause decompensation during the acute edematous phase of nephritis. However, signs of circulatory congestions are evident. The heart is enlarged, and increase pulmonary vascular marking are evident on x-ray examination. Increase pulmonary capillary permeability is also believed to be an important factor in the development of pulmonary edema.
ARF with persistent oliguria or anuria is an uncommon complication but one that requires an appropriate treatment regimen.