Liver Abscess Caused by Edwardsiella tarda: A Case Report

Edwardsiella tarda is a member of the family Enterobacteriaceae, commonly found in tropical and subtropical aquatic environments. Most E. tarda infections are linked to exposure to water or animals that inhabit water. However, it is still an uncommon pathogen in humans and causes mainly watery diarrhea. We describe a case of liver abscess caused by E. tarda. A 60-yr-old Korean man, with underlying diabetes mellitus, had a 10-day stay in Egypt 15 days before presentation. Ultrasound-guided percutaneous transhepatic abscess aspiration was performed. Pus culture revealed E. tarda, which was susceptible to all the antibiotics commonly used against Gram-negative organisms. The patient was treated with cefobactam for 10 days and piperacillin/tazobactam for another 5 days combined with an additional abscess aspiration due to recurrent fever. This therapy led to clinical improvement. The possible source of infection in this case may have been the drinking water supplied during travel in Egypt, but we cannot completely rule out a domestic source, because a liver abscess caused by E. tarda has been reported in a Japanese patient without travel history. Considering the Korean custom of eating raw fish or shrimp, climate changes, and increasing international travel, infections due to E. tarda may increase in Korea. Clinical microbiologists should be aware of this potential pathogen, and prompt investigation of the infection source and site is needed.

Distribution of Antigenic Aberration in the Bone Marrow of Acute Leukemia in Complete Remission / 대한진단검사의학회지

BACKGROUND: The aberrant, leukemia-associated antigen expression patterns allow us to discriminate leukemic blasts from normal precursor cells. Our major goal was to determine a guideline for the detection of minimal residual disease using CD20+/CD34+ and myeloid Ag+/CD19+ combination in the bone marrow of acute leukemia in complete remission (CR) after chemotherapy. METHODS: Bone marrow samples from 117 patients with acute leukemia in complete remission after chemotherapy and from 22 healthy controls were immunophenotyped by triple staining and measured by flow cytometry. RESULTS: The CD20+/CD34+ cells in the large lymphocyte gate (R1) ranged from 0% to 3.24% (0.8+/-0.82%, P=0.000) in CD20+/CD34+ B-lineage ALL CR (N=31), from 0.03% to 4.2% (0.7+/-0.83%, P=0.000) in CD20-/CD34- B-lineage ALL CR (N=66), from 0.1% to 0.96% (0.45+/-0.32%, P=0.016) in T-ALL CR (N=10), and from 0.02% to 0.48% (0.18+/-0.15%, P=0.776) in AML CR (N=10). The CD13,33+/CD19+ cells in R1 gate ranged from 0% to 2.69% (0.37+/-0.48%, P<0.001) in CD13,33+/CD19+ B-lineage ALL CR (N=31), from 0% to 1.8% (0.31+/-0.28%, P<0.001) in CD13,33-/CD19+B-lineage ALL CR (N=65), from 0.02% to 0.64% (0.29+/-0.22%, P=0.071) in T-ALL CR (N=9), and from 0% to 0.17% (0.07+/-0.09%, P=0.341) in AML CR (N=3). CONCLUSIONS: Using an immunophenotypic method for the detection of early relapse or minimal residual disease of B-lineage ALL bone marrow in CR after chemotherapy, different cutoff values should be applied according to antigen combination and gating. When the proportion of aberrant antigen combination was less than 5% in large lymphocyte gate, the results should be interpreted with caution.