369. Tissue Based Species Level Molecular Identification of Schistosoma haematobium in Appendiceal Tissue


 
 
 Appendiceal involvement in schistosomiasis is rare, but it has been reported for the 3 major species commonly infecting humans (S. haematobium, S. mansoni, and S. japonicum). Often the diagnosis is made histologically following appendectomy. However, many times the eggs found in the appendiceal tissue are calcified or degraded to a degree that a species level diagnosis cannot be made morphologically.
 Case presentation: A 37-year-old Somali female patient presented with chronic abdominal pain. An appendectomy was performed due to the finding of appendicitis on an abdominal CT. A biopsy sent to pathology showed calcified eggs consistent with Schistosoma (Figure 1), but a species could not be defined. Serum Schistosoma IgG was negative.
 Eggs of Schistosoma Species Figure 1:Miscroscopy of degraded eggs of Schistosoma species.
 
 
 
 The biopsy was then sent to the Laboratory of Parasitic Diseases at the National Institutes of Health (NIH) for qPCR and molecular indentification. DNA was extracted from two unstained biopsy slides using standard techniques for formalin-fixed, paraffin embedded tissue and subjected to qPCR using S. heaematobium- or S.mansoni-specific primers/probes.
 
 
 
 The patient sample only amplified (Ct value -32) with the S. haematobium-specific primers/probes and not with the S. mansoni-specific primers/probes (no amplification). For both qPCR reactions, positive controls were positive and negative controls showed no amplification.
 
 
 
 Tissue-based parasite identification of S. haematobium DNA provides a definitive species assignment for the causative agent presumably driving the appendiceal inflammation. This technique further allows species-based therapeutics, should it be necessary.
 
 
 
 All Authors: No reported disclosures.
