Table 2.
Summary of the Laboratory Data for 13 Patients With Asymptomatic Intestinal Entamoeba histolytica Infection
| Case ID | Age, y | Sex | Chief Complaint or Reason for Referral | Endoscopy | Serum Anti–Entamoeba histolytica AbTitera | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Stool Examination | Macroscopic Findings | Intestinal Fluid Examination | Histopathology of Biopsied Sample | |||||||
| O&P | PCR | O&P | PCR | |||||||
| 11 | 41 | M | Anti–E. histolytica Ab positive | Negative | Negative | Erosions in the cecum | Trophozoite | Positive | Negative | 400 |
| 104 | 40 | F | FOB test positive | Negative | Positive | Ulcer in the cecumb | NA | NA | Positiveb | NA |
| 71 | 45 | M | Extrapulmonary tuberculosis | Negative | Positive | NA | NA | NA | NA | Negative |
| 77 | 68 | F | Complete medical examination | Cyst | Positive | NA | NA | NA | NA | 400 |
| 92 | 45 | M | Anti–E. histolytica Ab positive | Cyst | Positive | NA | NA | NA | NA | 400 |
| 93 | 42 | M | Anti–E. histolytica Ab positive | Cyst | Positive | NA | NA | NA | NA | 800 |
| 99 | 29 | M | Anti–E. histolytica Ab positive and LFT elevation | Cyst | Positive | NA | NA | NA | NA | 1600 |
| 120 | 45 | M | LFT elevation | Cyst | Positive | NA | NA | NA | NA | NA |
| 124 | 56 | M | Complete medical examination | Cyst | Positive | NA | NA | NA | NA | NA |
| 53 | 38 | M | FOB test positive | NA | NA | Ulcer with exudates in the cecum | Trophozoite | Positive | Positive | 100 |
| 73 | 58 | M | FOB test positive | NA | NA | Multiple erosions with exudates in the cecum | Trophozoite | Positive | Negative | Negative |
| 105 | 52 | M | Complete medical examination | NA | NA | Multiple erosions in the cecum | Trophozoite | Positive | Positive | NA |
| 54 | 49 | M | Kaposi sarcoma | NA | NA | Multiple ulcers and bumpsc with exudates from the cecum to the transverse colon | Negative | Positive | Positive | 100 |
Abbreviations: Ab, antibody; F, female; FOB, fecal occult blood; ID, identification number; LFT, liver function test; M, male; NA, not available; O&P, ova and parasite examination; PCR, polymerase chain reaction.
aAnti–E. histolytica antibody was measured by an indirect immunofluorescence assay. This commercial antibody test was only available until 2017 in Japan, so it could not be used for the samples from 2018 (cases 104–124).
bIn case 104, endoscopy was performed by the previous doctor and only a stool test was performed at our hospital.
cBump was defined as edematous swollen mucosa caused by acute inflammation.