Could you check your lab reports and see if you also had high eosinophils? Eosinophilia is also a sign of tissue-invading helminthes.
I have/had every parasite there is, and multiple stool tests came back negative. The only blood test I had was for strongyloides and it came back positive.
My early blood work showed low red blood cells, high white blood cells and high eosinophil levels.