Department of Infectious and Parasitic Disease Pathology, Armed Forces Institute of Pathology, American Registry of Pathology, Department of Infectious and Parasitic Disease Pathology, Armed Forces Institute of Pathology, Washington, DC
The objective of this project was to demonstrate detection of Cryptosporidium parvum DNA in fixed, paraffin-embedded tissue using the polymerase chain reaction (PCR). DNA was purified from six samples of fixed, paraffin-embedded tissue that were histologically positive for C. parvum and used in the PCR. Previously developed oligonucleotide primers specific for C. parvum were used to amplify a 452-base target sequence, and a 20-base synthetic probe labeled with digoxigenin-11-dUTP was used to detect the amplification product by chemiluminescence. All six samples were positive by PCR; negative controls showed no amplification or hybridization. This approach could provide a sensitive and specific method for detection of parasite material in fixed, paraffin-embedded tissue samples, and prove to be of significant value in retrospective studies of archival material.