News and Updates

Change in Parasite Testing

TO:  Regional Medical Laboratory (RML) Clients
FROM: Linda Strycker, MT (ASCP), Microbiology Manager
Gerald C. Miller, PhD, Chief of Microbiology and Immunology
DATE: August 3, 2009
SUBJECT: Change in Parasite Testing

Recent literature indicates the most common parasites in the United States are Giardia lamblia and Cryptosporidium sp. Regional Medical Laboratory’s internal study also supports this data. Giardia and Cryptosporidium account for over 90% of the parasites reported at RML in the past five years. Giardia lamblia is the most common, and Cryptosporidium is the second most common of the intestinal parasites. However, Cryptosporidium may not be detected by the traditional O&P test. Therefore, antigen testing is the preferred method for screening for these organisms since it is more sensitive and effective in detecting and identifying both parasites. In an effort to provide optimal patient care testing, while decreasing costs to the patient and improving turn around time, the RML microbiology laboratory, based on the above internal information and the literature is modifying parasite testing.

Effective September 1, 2009, Regional Medical Laboratory will convert all orders for C PARASITE to the C PARA SC. The order name of C PARA SC will generate the immunoassay antigen test which screens for both Giardia lamblia and Cryptosporidium sp. When a C PARA SC is ordered and performed, specimens with negative screen results will be held for one week for convenience of the physician if further testing is desired. The test results will report either positive or negative for each organism.

A comprehensive ova and parasite test (C PARASPEC; CPT codes 87177 & 87209) will be available but only if the patient meets one or more of the following conditions. 

  • Previous Giardia/Cryptosporidium screen is negative but persistent diarrhea symptoms continue.
  • Recent travel outside the U.S.
  • Immunocompromised patient
  • New immigrant
  • Transplant patient 
  • Special circumstances

The previous orderable tests for Cryptosporidium (C CRYPTOSP) and Giardia lamblia (GIARD FEC) by DFA are no longer available. If these tests are ordered, the C PARA SC test will be performed. The CPT codes for the updated C PARA SC are 87328 and 87329.

The specimen to be submitted to the laboratory is stool placed in PVA and Formalin vials (Parapak) ASAP after passage. The tests will be performed Monday through Friday.

Please contact Linda Strycker, MT (ASCP), Microbiology Section Manager at 918-744-3131, ext 15575 or Gerald C. Miller, PhD, at 918-744-2553 or 800-722-8077 with any questions or concerns regarding parasite testing.