Final answer:
Eosinophils in the urine are often associated with acute glomerulonephritis, which can be due to conditions such as Goodpasture's syndrome, Wegener's granulomatosis, and lupus nephritis. They might also indicate allergic interstitial nephritis or a parasitic kidney infection.
Step-by-step explanation:
The presence of eosinophils in the urine suggests a renal pathology such as acute glomerulonephritis. This condition can be due to various causes, including anti-glomerular basement membrane disease/Goodpasture's syndrome, Wegener’s granulomatosis, or acute lupus nephritis with systemic lupus erythematosus. Eosinophils typically fight parasitic infections and are involved in allergic reactions, so their presence in the urine can also hint at an allergic interstitial nephritis or a parasitic infection affecting the kidneys.
In cases of a suspected autoimmune condition like systemic lupus erythematosus, the presence of eosinophils could be a part of a broader set of diagnostic findings, such as proteinuria, hematuria, and possibly a low hematocrit, indicating a potential autoimmune process.