Chung Hyun Nahm

Allergen Specific IgE Measurement with Polycheck Allergy: Comparison of Three Multiple Allergen Simultaneous Tests

BACKGROUND The in vivo skin prick test (SPT) or in vitro detection of allergen specific IgE in serum is commonly used for the diagnosis of allergic disease. In this study, we evaluated the usefulness of a new multiple allergen simultaneous test (MAST) immunoblot assay, Polycheck Allergy (Biocheck GmbH, Germany). METHODS A total of 100 patients with clinical findings of allergic diseases were tested by SPT and three different MAST assays: Polycheck Allergy (Biocheck GmbH, Germany), MAST CLA allergy system (Hitachi Chemical Diagnostics, USA) and Allergy Screen (R-biopharm, Germany). The results of MAST assays were compared with those of SPT. RESULTS Concordance rates of MAST assays with SPT were 79-100% for Polycheck Allergy, 88.9-100% for MAST CLA and 72.7-98.3% for Allergy Screen. In ROC curve analysis, significant differences were observed in four of 25 allergens analysed: Alternaria, Birch, Hazelnut and D. farinae. For Alternaria and Birch, Polycheck Allergy (P<0.001) and Allergy Screen (P=0.0075) showed significantly larger AUC (area under the curve) than MAST CLA. For Hazelnut, Polycheck Allergy (P=0.0021), and for D. farinae, MAST CLA (P=0.015) showed significantly larger AUCs than the other two tests. The ROC analysis for overall 16 food allergens showed better results in Polycheck Allergy (P<0.001), and that for overall 21 inhalants did not show significant differences among three MAST assays (P>0.05). CONCLUSIONS Since Polycheck Allergy showed similar or superior result to the others, it can be used for the detection of allergen specific IgE antibodies.

A Case of Blastic Plasmacytoid Dendritic Cell Neoplasm Initially Mimicking Cutaneous Lupus Erythematosus

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare disease. The prognosis is poor in most cases with rapid progression despite administering chemotherapy. A 67-year-old man complained of skin rashes on his back and this spread to the trunk, face, arms and thighs, and he was initially diagnosed with cutaneous lupus erythematosus according to the skin biopsy. The skin rashes then became aggravated on a trial of low dose methylprednisolone for 3 months. Repeated skin biopsy revealed a diffuse infiltration of lymphoid cells with medium sized nuclei, positive for CD4 and CD56, negative for Epstein-Barr virus (EBV), indicating a diagnosis of BPDCN. Further workups confirmed stage IVA BPDCN involving the skin, multiple lymph nodes, the peripheral blood and the bone marrow. He was treated with six cycles of combination chemotherapy consisting of ifosphamide, methotrexate, etoposide, prednisolone and L-asparaginase, and he achieved a partial response. Herein we report on a rare case of BPDCN that was initially misinterpreted as cutaneous lupus erythematosus.

Significance of KIT exon 17 mutation depends on mutant level rather than positivity in core-binding factor acute myeloid leukemia.

KIT exon 17 mutation is a poor prognostic factor in core-binding factor acute myeloid leukemia. However, the mutation detection method used for risk assessment is not assigned. It is necessary to verify the analytical and clinical performance before applying new methods. Herein, we firstly applied a highly sensitive allele-specific, real-time quantitative PCR (AS-qPCR) assay to analyze KIT mutations, which demonstrated excellent sensitivity and specificity. Much higher incidence of KIT mutations (62.2%, 69/111) and prevalence of multiple mutations (43.5%, 30/69) were observed using AS-qPCR, which meant the existence of multiple KIT mutant subclones. The relative KIT mutant level was variable (median, 0.3 per control allele 100 copies, 0.002–532.7) and was divided into two groups: high (⩾10, n=26) and low (<10) mutant level. Interestingly, rather than mutation positivity, mutant level was found to be associated with clinical outcome. High mutant level showed significantly inferior overall survival (P=0.005) and event-free survival (P=0.03), whereas low level did not influence the prognosis. The follow-up data showed that the mutant level were along with fusion transcripts in the majority (n=29), but moved separately in some cases, including the loss of mutations (n=5) and selective proliferation of minor clones (n=2) at relapse. This study highlighted that the KIT mutation should be analyzed using sensitive and quantitative techniques and set a cutoff level for identifying the risk group.

Aberrant cystatin‑C expression in blood from patients with breast cancer is a suitable marker for monitoring tumor burden

The present study was performed to evaluate the efficacy of circulating cystatin-C as a tumor monitoring biomarker at different clinical time points in patients with breast cancer over a long-term follow-up period. In addition, the secretory rate of circulating cystatin-C from cancer tissue was investigated by comparing the blood and tissue expression levels of cystatin-C. Blood samples from healthy volunteers (40 males and 40 females) were obtained at yearly health examinations if laboratory and imaging abnormalities were not detected. Blood samples from 34 patients with breast cancer were obtained at 205 different time points of clinical progression. Blood levels of cystatin-C were measured using ELISA and the tissue levels were measured using immunohistochemistry. No age-associated effect was observed in male and female blood cystatin-C levels. The positivity rate was 46% in patients (38/83) and 40% in samples collected at different time points (82/205). Blood cystatin-C levels were lowest following surgery compared with patients with systemic metastasis (P<0.001). The sensitivity, specificity and accuracy rates of ELISA were 53.6, 63.6 and 53.9%, respectively. The concordance rate between blood and tissue expression was 38%. The main reason for discordance between tissue and serum expression of cytostatin-C came from low serum positivity in samples showing tissue cytostatin-C (3/11, 27%). The specificity between cytostatin-C and CA-125 was highest in tumor absence state. In conclusion, elevated blood levels of cystatin-C were observed in 40% of breast cancer cases and were tumor-volume dependent. However, the concordance rate between tissue and blood was quite low, suggesting tumor heterogeneity of cystatin-C expression or co-acting pathway activation, such as cathepsin D. As one-third of breast cancer tissues express cystatin-C without cancer antigen 15-3 elevation, cystatin-C may represent a good tumor-monitoring marker in breast cancer.

A Case of Anaerobiospirillum succiniciproducens Isolated from Blood Culture

Anaerobiospirillum succiniciproducens is a spiral-shaped, gram-negative anaerobic bacterium. A. succiniciproducens is a rare cause of bacteremia in human, especially immunocompromised patients. This organism may be mistakenly identified when using an automated bacterial identification system, and may be mistaken for Campylobacter spp. when using Gram staining. We report a case of bacteremia caused by A. succiniciproducens, which was negative for catalase, oxidase, and urease and confirmed by 16S rRNA sequencing (analysis revealed a 99% similarity), in a 69-year-old patient who was undergoing chemotherapy for treatment of a malignancy. To the best of our knowledge, this is the first report of bacteremia caused by A. succiniciproducens in Korea. (Korean J Clin Microbiol 2012;15:74-77)

A case of multiple myeloma possibly cured by autologous blood stem cell transplantation

Cure of multiple myeloma is a rarity despite latest development of potent novel therapies. Although there have been handful reports of cure, no survival plateau has been achieved. A 50-year-old Korean woman was diagnosed as immunoglobulin G kappa multiple myeloma in international stage III without cytogenetic abnormality. Her serum M protein was 4.51 g/dL, beta2 microglobulin 3.8 mg/L, albumin 3.1 g/dL and creatinine 1.3 mg/dL. Marrow study revealed more than 70% cellularity with plasma cells comprising 54% of mononuclear cells (MNC). No cytogenetic abnormality was found on marrow culture. Fluorescence in situ hybridization was not carried out for it was unavailable at that time. Extensive osteolytic bony lesions were found in whole axial bones, including skull, spines, ribs and pelvis. She received 12 courses of chemotherapy consisting of cyclophosphamide 400 mg and dexamethasone 40 mg for five consecutive days every 4 weeks from August 1996 to June 1997. M protein became undetectable at the eighth cycle on serum immunofixation. As compression fracture in T9, T12 and L2, vertebral bodies ensued, radiotherapy was delivered to her dorsal spines (T7–T11) at 2100 cGy in seven fractions in January 1997 with palliative intent. In November 1997 she received high-dose chemotherapy comprising melphalan at 100 mg/m for 2 days followed by blood stem cell support at a dose of 4.88 ¥ 10 MNC/kg or 5.44 ¥ 10 CD34+ cells/kg, harvested after mobilization by cyclophosphamide at 3 g/m and granulocyte colonystimulating factor at 5 mg/kg. A bone marrow study in December 1997 documented good engraftment. She has been free of myeloma for longer than 11 years with no evidence of disease on physical exam, marrow study, blood counts and chemistries, including serum immunofixation for M protein. Although myeloma has been thought to be a chemosensitive tumour, it is very difficult to eradicate even with tandem transplantation regardless whether using double autologous or auto followed by allogeneic transplant. Autologous blood stem cell transplant has emerged as potent therapy for the extension of survival in myeloma. However, it is not clear why some patients do not benefit from a second transplant procedure. It is possible that dormant cancer stem cells are resistant to currently available high-dose chemotherapy. There are reported cases of cure by chemotherapy alone obtained using melphalan or bischlorethyl nitrosourea-based regimens. We used cyclophosphamide and dexamethasone as well as consolidation with high-dose melphalan with no novel agents. Although it is an old drug, cyclophosphamide still remains an active drug with little haemopoietic stem cell toxicity. Among 24 treatment-naïve patients in 1996–2003, the combination of cyclophosphamide and dexamethasone yielded eight very good responders in our institution. Four of them received autologous stem cell transplant with the same method, and only one remains a long-term diseasefree survivor. It is uncertain whether chemotherapy alone is adequate therapy. The case is an example of an extremely chemosensitive disease in which an excellent long-term outcome appears a cure, suggesting that biological differences in individual cases of myeloma may impact on treatment outcome more than the specifics of therapy.

Characteristics of non-anemic healthy adolescents with serum-soluble transferrin receptor concentrations outside the reference interval

Dear Editor, Iron transport in the body is carried out by the binding of iron to a specific carrier protein, transferrin. The transferrin receptor (TfR) mediates the flow of serum iron from the extracellular pool into the cytoplasm by receptor-mediated endocytosis [1]. Virtually, all cells have TfR on their surface, but most of TfR are located in the erythroid precursors of the bone marrow and the peripheral immature reticulocytes. Serum-soluble transferrin receptor (sTfR) is a truncated monomer of tissue receptor, which circulates in the form of a complex of transferrin and its receptor [2]. The sTfR has been suggested as a good estimate of body iron status and a biochemical maker of iron-deficient erythropoiesis [3, 4]. Increased sTfR concentrations are usually observed in iron deficiency anemia (IDA), or in cases of iron depletion in tissues, because iron deprivation induces a synthesis of TfR. Conditions associated with erythroid hyperplasia, such as immune hemolytic anemia and thalassemia, can also increase the value of sTfR, irrespective of body iron status [5]. Healthy subjects, who had no evidence of iron depletion and hemolytic anemia, sometimes exhibit a higher sTfR concentration than the patients with iron deficiency. Similarly, some IDA patients show much more diminished sTfR concentrations than non-anemic individuals. In the previous study, we reported that IDA patients who were not accompanied by an increase in sTfR levels are linked to the diminution of immature reticulocyte production [6]. There have been few studies that have closely examined the healthy subjects with serum sTfR concentrations outside the reference interval. In the current study, we investigated the features of the non-anemic healthy individuals, who did not reach the lower limit or exceeded the upper limit of the reference range in serum sTfR levels. A total of 92 healthy adolescents (49 males and 43 females) with a median age of 18 years (range 17–19 years), who displayed the abnormal results in serum sTfR concentrations but showed no evidence of anemia, iron depletion, or hemolytic diseases, were enrolled. Adolescents showing normal values in serum iron parameters (serum ferritin >12 μg/l; serum iron >50 μg/dl) and normal hemoglobin levels (>12 g/dl) were defined as the non-anemic healthy individuals. Subjects with the history of recent infections (n=2) and vitamin supplementation (n=2) were excluded from this study, because these conditions may influence serum iron parameters and erythropoietic activity. Subjects were investigated by measurements of hematologic variables, serum iron profiles, and reticulocyte parameters [i.e., immature reticulocyte fraction (IRF) and reticulocyte maturity index (RMI)]. The cutoff levels of sTfR for the subject populations were determined as 1.18 and 3.23 mg/l, which were based on the reference interval in age-matched adolescents [7]. Subject populations were categorized as two groups, and the subjects with decreased sTfR <1.18 mg/l (n=52) were compared to those with increased sTfR >3.23 mg/l (n=40), especially focused on IRF, RMI, and iron parameters. Ann Hematol (2008) 87:571–573 DOI 10.1007/s00277-008-0456-1