Treatment For Scabbies Was Started Without Testing When Patient Presented

Treatment for scabbies was started without testing when patient presented with similar symptoms.
Three doses of Permytheryn ointment and two doses of oral Ivermectin.
Scabbies was R/o as the tests suggested there was no indication and patient physical evidence indicates no intimate or sexual relationships for 7 or more years nor opportunity for exposure to occur. Elevated LDH levels, Purpura skin rash continues to present, urtikaria randomly occurs. Prednizone has been administered for a period of 2 weeks, however it has not been effective for cessation of horrific itching. This issue has been going on for 4 plus mos. What would you suggest should be the next step taken? Should a one time exposure to Avian dung be considered? What labs could be considered to have an epidemiologist Dx this? Most labs are not proficient with this type of Dx.