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Background@#Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. @*Methods@#S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. @*Results@#Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. @*Conclusions@#Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.
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Background@#In Korea, the first community outbreak of coronavirus disease 2019 (COVID-19) occurred in Daegu on February 18, 2020. This study was performed to investigate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in healthcare workers (HCWs) at 6 major hospitals in Daegu. @*Methods@#Blood specimens of 2,935 HCWs at 6 major hospitals in Daegu from January 2021 to February 2021 were collected. Every specimen was tested for antibody against SARS-CoV-2 using both Elecsys Anti-SARS-CoV-2 electrochemiluminescence immunoassay (Roche Diagnostics, Rotkreuz, Switzerland) and R-FIND COVID-19 IgG/M/A enzyme-linked immunosorbent assay kit (SG medical Inc., Seoul, Korea) as screening tests. If 1 or more of these screening test results was positive, 2 additional antibody tests were performed using Abbott Anti-SARS-CoV-2 IgG assay (Abbott, Abbott Park, IL, USA) and cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript USA Inc., Piscataway, NJ, USA). If 2 or more of the total 4 test results were positive, it was determined as positive for the antibody against SARS-CoV-2. @*Results@#According to the criteria of SARS-CoV-2 antibody positivity determination, 12 subjects were determined as positive. The overall positive rate of the SARS-CoV-2 antibody was 0.41% (12/2,935). Of the 12 subjects determined as positive, 7 were diagnosed with COVID-19, and the remaining 5 were nondiagnosed cases of COVID-19. @*Conclusion@#In early 2021, the overall seroprevalence of SARS-CoV-2 antibody among HCW located in Daegu was 0.41%, and 0.17% excluding COVID-19 confirmed subjects. These results were not particularly high compared with the general public and were much lower than HCWs in other countries.
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Background@#A coronavirus disease 2019 (COVID-19) outbreak started in February 2020 and was controlled at the end of March 2020 in Daegu, the epicenter of the coronavirus outbreak in Korea. The aim of this study was to describe the clinical course and outcomes of patients with COVID-19 in Daegu. @*Methods@#In collaboration with Daegu Metropolitan City and Korean Center for Diseases Control, we conducted a retrospective, multicenter cohort study. Demographic, clinical, treatment, and laboratory data, including viral RNA detection, were obtained from the electronic medical records and cohort database and compared between survivors and non-survivors. We used univariate and multi-variable logistic regression methods and Cox regression model and performed Kaplan–Meier analysis to determine the risk factors associated with the 28-day mortality and release from isolation among the patients. @*Results@#In this study, 7,057 laboratory-confirmed patients with COVID-19 (total cohort) who had been diagnosed from February 18 to July 10, 2020 were included. Of the total cohort, 5,467 were asymptomatic to mild patients (77.4%) (asymptomatic 30.6% and mild 46.8%), 985 moderate (14.0%), 380 severe (5.4%), and 225 critical (3.2%). The mortality of the patients was 2.5% (179/7,057). The Cox regression hazard model for the patients with available clinical information (core cohort) (n = 2,254) showed the risk factors for 28-day mortality: age > 70 (hazard ratio [HR], 4.219, P = 0.002), need for O 2 supply at admission (HR, 2.995; P = 0.001), fever (> 37.5°C) (HR, 2.808; P = 0.001), diabetes (HR, 2.119; P = 0.008), cancer (HR, 3.043; P = 0.011), dementia (HR, 5.252; P = 0.008), neurological disease (HR, 2.084; P = 0.039), heart failure (HR, 3.234;P = 0.012), and hypertension (HR, 2.160; P = 0.017). The median duration for release from isolation was 33 days (interquartile range, 24.0–46.0) in survivors. The Cox proportional hazard model for the long duration of isolation included severity, age > 70, and dementia. @*Conclusion@#Overall, asymptomatic to mild patients were approximately 77% of the total cohort (asymptomatic, 30.6%). The case fatality rate was 2.5%. Risk factors, including older age, need for O 2 supply, dementia, and neurological disorder at admission, could help clinicians to identify COVID-19 patients with poor prognosis at an early stage.
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The cause of epithelioid granulomatous inflammation varies widely depending on the affected organ, geographic region, and whether the granulomas morphologically contain necrosis. Compared with other organs, the etiological distribution and morphological patterns of pleural epithelioid granulomas have rarely been investigated. We evaluated the final etiologies and morphological patterns of pleural epithelioid granulomatous inflammation in a tuberculosis (TB)-prevalent country. Of 83 patients with pleural granulomas, 50 (60.2%) had confirmed TB pleurisy (TB-P) and 29 (34.9%) had probable TBP. Four patients (4.8%) with non-TB-P were diagnosed. With the exception of microbiological results, there was no significant difference in clinical characteristics and granuloma patterns between the confirmed TB-P and non-TB-P groups, or between patients with confirmed and probable TB-Ps. These findings suggest that most pleural granulomatous inflammation (95.2%) was attributable to TB-P in TB-endemic areas and that the granuloma patterns contributed little to the prediction of final diagnosis compared with other organs.
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Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in upper and lower respiratory specimens and coinfection with other respiratory pathogens in patients with coronavirus disease 2019 (COVID-19) were investigated. From the study subjects (N = 258) retrospectively enrolled when confirmed as SARS-CoV-2 positive, nasopharyngeal (NPS), oropharyngeal swabs (OPS), and sputum specimens were restored for retesting SARS-CoV-2 and detecting respiratory pathogens. Majority of the study subjects (95.7%, N = 247) were confirmed as SARS-CoV-2 positive using NPS/OPS specimens, suggesting that the upper respiratory specimen is most valuable in detecting SARS-CoV-2. Coinfection rates in COVID-19 patients (N = 258) with respiratory pathogens were 9.7% (N = 25); 8.5% (N = 22) respiratory viruses and 1.2% (N = 3) Mycoplasma pneumoniae, an atypical bacterium. Of the respiratory virus coinfection cases (N = 22), 20 (90.9%) were co-infected with a single respiratory virus and 2 (0.8%) (metapneumovirus/adenovirus and rhinovirus/bocavirus 1/2/3/4) with two viruses. Respiratory viruses in single viral coinfection cases with SARS-CoV-2 were as follows: non-SARS-CoV-2 coronaviruses (229E, NL63, and OC43, N = 5, 1.9%), rhinovirus (N = 4, 1.6%), metapneumovirus (N = 3, 1.2%), influenza A (N = 3, 1.2%), respiratory syncytial virus A and B (N = 3, 1.2%), and adenovirus (N = 2, 0.8%). No mixed coinfections with respiratory viruses and M. pneumoniae were found. In conclusion, the diagnostic value of utilizing NPS/OPS specimen is excellent, and, as the first report in Korea, coinfection with respiratory pathogens were detected at a rate of 9.7% in patients with COVID-19.
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Pestalotiopsis species are filamentous fungi that are known plant pathogens commonly isolated in tropical and subtropical regions. To the best of our knowledge, this is the first case of human infection caused by Pestalotiopsis mangiferae. An 80-year-old male farmer presented with ocular pain in the right eye. At initial presentation, slit-lamp examination showed a 3.0×2.5 mm-sized epithelial defect in the cornea of the right eye accompanied by corneal thinning. A KOH examination revealed spores, and consequently, treatment with voriconazole, ceftazidime, and moxifloxacin was initiated. One month later, a second KOH examination and fungal culture were performed. The results of the KOH examination indicated the presence of many hyphae, and fungus was isolated from the culture. Molecular identification revealed that the sequence had 100% similarity to P. mangiferae. The patient was treated with therapeutic penetrating keratoplasty. During follow-up in the outpatient clinic, signs of infection were not observed.
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BACKGROUND: Several factors contribute to differences in Streptococcus pneumoniae serotype distribution. We investigated the serotype distribution and antimicrobial resistance of S. pneumoniae isolated between 2014 and 2016 in Korea. METHODS: We collected a total of 1,855 S. pneumoniae isolates from 44 hospitals between May 2014 and May 2016, and analyzed the serotypes by sequential multiplex PCR. We investigated the distribution of each serotype by patient age, source of the clinical specimen, and antimicrobial resistance pattern. RESULTS: The most common serotypes were 11A (10.1%), followed by 19A (8.8%), 3 (8.5%), 34 (8.1%), 23A (7.3%), and 35B (6.2%). The major invasive serotypes were 3 (12.6%), 19A (7.8%), 34 (7.8%), 10A (6.8%), and 11A (6.8%). Serotypes 10A, 15B, 19A, and 12F were more common in patients ≤5 years old, while serotype 3 was more common in patients ≥65 years old compared with the other age groups. The coverage rates of pneumococcal conjugate vaccine (PCV)7, PCV10, PCV13, and pneumococcal polysaccharide vaccine 23 were 11.8%, 12.12%, 33.3%, and 53.6%, respectively. Of the 1,855 isolates, 857 (46.2%) were multi-drug resistant (MDR), with serotypes 11A and 19A predominant among the MDR strains. The resistance rates against penicillin, cefotaxime, and levofloxacin were 22.8%, 12.5%, and 9.4%, respectively. CONCLUSIONS: There were significant changes in the major S. pneumoniae serotypes in the community. Non-PCV13 serotypes increased in patients ≤5 years old following the introduction of national immunization programs with the 10- and 13-polyvalent vaccines.
Subject(s)
Humans , Cefotaxime , Immunization Programs , Korea , Levofloxacin , Multiplex Polymerase Chain Reaction , Penicillins , Pneumococcal Vaccines , Pneumonia , Serogroup , Streptococcus pneumoniae , Streptococcus , VaccinesABSTRACT
BACKGROUND: Here we investigated the clinical utilities of blast suspect, large unstained cell (LUC), delta neutrophil index ll (DN ll), and delta neutrophil index l (DN l), analyzed in peripheral blood samples with automated hematology analyzers to predict the relapse of acute leukemia. METHODS: We retrospectively reviewed the medical records of 112 patients, including 56 patients with acute leukemia relapse and 56 controls. Blast suspect, LUC, DN ll, and DN l were compared between the control and leukemia relapse groups. RESULTS: Significant differences in blast suspect (P<0.001), LUC (P<0.001), DN ll (P<0.001), and DN l (P=0.002) were observed between the leukemia relapse and control groups. The areas under the curve (AUC) value was 0.927 for blast suspect (95% confidence interval [CI]: 0.8750.978, P<0.001), 0.868 for LUC (95% CI: 0.794–0.941, P<0.001), and 0.900 for DN ll (95% CI: 0.841–0.960, P<0.001). Logistic regression analysis for the prediction of leukemia relapse revealed odds ratio values of 1.52 (95% CI: 1.26–1.96, P=0.0002) for blast suspect, 1.66 (95% CI: 1.27–2.42, P=0.0019) for LUC, 1.16 (95% CI: 1.08–1.29, P=0.0014) for DN ll, and 1.05 (95% CI: 1.01–1.13, P=0.0845) for DN l. CONCLUSIONS: Multiple parameters provided by automated blood cell analyzers may serve as powerful ancillary tools for the prediction and diagnosis of leukemia relapse.
Subject(s)
Humans , Blood Cells , Diagnosis , Hematology , Leukemia , Logistic Models , Medical Records , Neutrophils , Odds Ratio , Recurrence , Retrospective StudiesABSTRACT
Neutrophilic leukemoid reaction may occur in many situations, including hemolysis, malignancy, infection, and exposure to certain toxins. It usually shows morphological overlap with chronic myeloid leukemia in which promyelocytes are not majorly associated. Here, we present a case of promyelocytic leukemoid reaction in a patient with sepsis. A 28-year-old man was admitted for renal stone removal. After percutaneous nephrolithotomy, his condition deteriorated with fever (37.8℃), tachycardia (130/min), acute renal failure, pleural effusion, and pulmonary edema. Complete blood count indicated a white blood cell count of 73.39×10⁹/L including 82% promyelocytes, hemoglobin 8.9 g/dL, and platelet count of 85×10⁹/L. A bone marrow aspirate showed that promyelocytes accounted for 73.8% of all nucleated cells. Following bone marrow examination, treatment with all-trans retinoic acid (ATRA) was started immediately. Reverse transcription polymerase chain reaction (RT-PCR) study revealed the absence of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) and other RARA (retinoic acid receptor alpha) rearrangements. Once the chromosome analysis of bone marrow cells demonstrated the normal karyotype, ATRA was discontinued.
Subject(s)
Adult , Humans , Acute Kidney Injury , Blood Cell Count , Bone Marrow , Bone Marrow Cells , Bone Marrow Examination , Fever , Granulocyte Precursor Cells , Hemolysis , Karyotype , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Leukemia, Promyelocytic, Acute , Leukemoid Reaction , Leukocyte Count , Nephrostomy, Percutaneous , Neutrophils , Platelet Count , Pleural Effusion , Polymerase Chain Reaction , Pulmonary Edema , Reverse Transcription , Sepsis , Tachycardia , TretinoinABSTRACT
BACKGROUND: Hemorheologic indices are known to be related to vascular complications in variable clinical settings. However, little is known about the associations between hemorheologic parameters and acute myocardial infarction (AMI) in type 2 diabetes mellitus (T2DM). The purpose of this study was to demonstrate the changes of hemorheologic environment inside of blood using hemorheologic parameters, especially the elongation index (EI) and critical shear stress (CSS) in diabetics with versus without AMI. METHODS: A total of 195 patients with T2DM were enrolled. Patients were divided into the study group with AMI (AMI+, n = 77) and control group (AMI−, n = 118) who had no history of coronary artery disease. Hemorheologic parameters such as EI and CSS were measured and compared between the two groups. RESULTS: The EI was lower (30.44%±1.77% in AMI+ and 31.47%±1.48% in AMI−, P < 0.001) but the level of CSS was higher (316.13±108.20 mPa in AMI+ and 286.80±85.34 mPa in AMI−, P = 0.040) in the AMI+. The CSS was significantly related to the erythrocyte sedimentation rate (R² = 0.497, P < 0.001) and use of dipeptidyl peptidase-4 inhibitors (R² = 0.574, P = 0.048). CONCLUSION: Diabetics with AMI resulted in adverse hemorheologic changes with lower EI and higher CSS compared to diabetic subjects without AMI. Evaluation of the hemorheologic parameters may provide valuable supplementary information for managing patients with AMI and T2DM.
Subject(s)
Humans , Blood Sedimentation , Coronary Artery Disease , Diabetes Mellitus, Type 2 , Erythrocyte Deformability , Hemorheology , Myocardial InfarctionABSTRACT
BACKGROUND: Pneumocystis is difficult to culture or detect in laboratory environments. Its ecology including the timing and method of transmission as well as environmental sources and communicability remain unclear. METHODS: We retrospectively evaluated the pattern and treatment outcome of Pneumocystis jirovecii pneumonia (PCP) in children with acute lymphoblastic leukemia (ALL) who received chemotherapy. RESULTS: A total of 56 patients with ALL were evaluated. While on chemotherapy, all patients received PCP prophylaxis. PCP were found in a total of 6 patients, including definite PCP in 2, probable PCP in 2, and possible PCP in 2 patients. There were no significant differences in sex, age group, National Cancer Institute risk group, or pneumocystis prophylaxis type between PCP and non-PCP groups. However, there was a significant statistical difference in the times of ALL diagnosis. Regarding recent chemotherapy at the time of PCP diagnosis, there were one induction, one consolidation, and four maintenance cases. All PCP patients were treated with high-dose sulfamethoxazole (100 mg/kg/day) and trimethoprim (20 mg/kg/day) intravenously. Five patients survived, while one patient with endotracheal mechanical ventilation therapy died due to respiratory failure in spite of aggressive treatment. CONCLUSION: Pediatric PCP became extremely rare due to routine prophylaxis in clinical practice of pediatric malignancy. Nevertheless, we analyzed patients with acute lymphoblastic leukemia who had received PCP prophylaxis for 14 years, and analyzed the clustered outbreaks of PCP. It is still important to emphasize the need for prophylaxis and to increase the level of attention and isolation under environmental and personal risk factors.
Subject(s)
Child , Humans , Compliance , Diagnosis , Disease Outbreaks , Drug Therapy , Ecology , Methods , Pneumocystis carinii , Pneumocystis , Pneumonia , Pneumonia, Pneumocystis , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Respiration, Artificial , Respiratory Insufficiency , Retrospective Studies , Risk Factors , Sulfamethoxazole , Treatment Outcome , TrimethoprimABSTRACT
The affiliation no. 4 was misprinted.
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BACKGROUND: Invasive fungal infections (IFIs) are a life-threatening problem in immunocompromised patients. Despite timely diagnosis and appropriate antifungal therapy, clinical outcomes of IFIs remain unsatisfactory, necessitating treatment with a combination of antifungal agents. Therefore, childhood leukemic patients treated with voriconazole plus caspofungin were evaluated for the safety and efficacy of the combination antifungal therapy to treat IFIs. METHODS: In this retrospective study, medical records were retrieved for patients admitted to the Pediatric Department of Yeungnam University Hospital, Daegu, South Korea, between April 2009 and May 2013. Medical records of 22 patients were analyzed. RESULTS: Of the 22 patients studied, nine (41%) had been diagnosed with probable IFI, and 13 (59%) with possible IFI. All patients, except one, were already receiving antifungal monotherapy for the treatment of neutropenic fever. After a diagnosis of IFI was confirmed, antifungal monotherapy was replaced with combination therapy. The study's overall response rate was 90.9%, with complete responses in 86.3% of the patients. Two patients experienced a side effect of a small increase in liver enzyme levels. CONCLUSION: Voriconazole plus caspofungin combination therapy is an effective and safe treatment for serious IFI in pediatric patients with acute leukemia.
Subject(s)
Child , Humans , Antifungal Agents , Aspergillosis , Diagnosis , Echinocandins , Fever , Immunocompromised Host , Korea , Leukemia , Liver , Medical Records , Retrospective Studies , VoriconazoleABSTRACT
No abstract available.
Subject(s)
Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Multiple Myeloma , Plasma Cells , PlasmaABSTRACT
Roseomonas is a genus of pink-pigmented nonfermentative bacilli. These slow-growing, gram-negative cocobacilli form pink-colored colonies on sheep blood agar. They differ from other pink-pigmented nonfermenters, including Methylobacterium, in morphology, biochemical characteristics, and DNA sequence. Roseomonas strains are rarely isolated in clinical laboratories; therefore, we report two cases in order to improve our ability to identify these pathogens. We isolated two strains of Roseomonas mucosa from the venous blood cultures of two patients, an 84-yr-old woman with common bile duct obstruction and a 17-yr-old male with acute myeloid leukemia who had an indwelling central-venous catheter for chemotherapy. The isolated strains were confirmed as R. mucosa by 16S rRNA sequencing.
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A man aged 78 yr with no history of chemotherapy or toxic exposure presented with a history of dyspnea and intermittent red urine for 3 months and several years, respectively. Hematologic data at admission were as follows: hemoglobin, 65 g/L; white blood cell count, 4.05x109/L; platelet count, 96x109/L; and reticulocyte count, 10.9%. A peripheral blood smear revealed polychromasia, nucleated red blood cells, and neutrophils with a non-lobulated nucleus. The bone marrow was hypercellular and exhibited an increase in erythroid precursors with trilineage dysplasia and our findings were suggestive of refractory cytopenia with multilineage dysplasia (RCMD). Karyotype of bone marrow cells was as follows: 45,XY,der(9;17)(p10;q10),add(18)(q11.2)[10]/45,idem,del(3)(q21)[10]. Other laboratory findings showed decreased serum haptoglobin, increased lactate dehydrogenase, and increased indirect bilirubin levels. Moreover, results of the direct/indirect antiglobulin test (Coombs' test) and paroxysmal nocturnal hemoglobinuria analysis with CD55, CD59, fluorescent aerolysin (FLAER), and CD24 were negative. Cold agglutinin and Donath-Landsteiner antibodies were not detected. This is a case of myelodysplastic syndrome (MDS) associated with hemolytic anemia and complex chromosomal abnormalities at presentation.
Subject(s)
Anemia, Hemolytic , Antibodies , Bilirubin , Bone Marrow , Bone Marrow Cells , Chromosome Aberrations , Coombs Test , Drug Therapy , Dyspnea , Erythrocytes , Haptoglobins , Hemoglobinuria, Paroxysmal , Karyotype , L-Lactate Dehydrogenase , Leukocyte Count , Myelodysplastic Syndromes , Neutrophils , Platelet Count , Reticulocyte CountABSTRACT
Patients with hemolytic-uremic syndrome (HUS) can rapidly develop profound anemia as the disease progresses, as a consequence of red blood cell (RBC) hemolysis and inadequate erythropoietin synthesis. Therefore, RBC transfusion should be considered in HUS patients with severe anemia to avoid cardiac or pulmonary complications. Most patients who are Jehovah's Witnesses refuse blood transfusion, even in the face of life-threatening medical conditions due to their religious convictions. These patients require management alternatives to blood transfusions. Erythropoietin is a glycopeptide that enhances endogenous erythropoiesis in the bone marrow. With the availability of recombinant human erythropoietin (rHuEPO), several authors have reported its successful use in patients refusing blood transfusion. However, the optimal dose and duration of treatment with rHuEPO are not established. We report a case of a 2-year-old boy with diarrhea-associated HUS whose family members are Jehovah's Witnesses. He had severe anemia with acute kidney injury. His lowest hemoglobin level was 3.6 g/dL, but his parents refused treatment with packed RBC transfusion due to their religious beliefs. Therefore, we treated him with high-dose rHuEPO (300 IU/kg/day) as well as folic acid, vitamin B12, and intravenous iron. The hemoglobin level increased steadily to 7.4 g/dL after 10 days of treatment and his renal function improved without any complications. To our knowledge, this is the first case of successful rHuEPO treatment in a Jehovah's Witness child with severe anemia due to HUS.
Subject(s)
Child , Child, Preschool , Humans , Male , Acute Kidney Injury , Anemia , Blood Transfusion , Bone Marrow , Erythrocytes , Erythropoiesis , Erythropoietin , Folic Acid , Hemolysis , Hemolytic-Uremic Syndrome , Iron , Jehovah's Witnesses , Parents , Religion , Vitamin B 12ABSTRACT
BACKGROUND: Recently, myeloproliferative leukemia (MPL) W515 mutations have been reported to be molecular markers for myeloproliferative neoplasms (MPNs). We studied the association between MPL W515 mutations and the clinico-hematological features of patients with MPNs. METHODS: Our study included 154 consecutive patients diagnosed with MPNs (31 had polycythemia vera [PV]; 106, essential thrombocythemia [ET]; and 17, primary myelofibrosis [PMF]). MPL W515 mutations were detected by real-time PCR and direct sequencing methods. RESULTS: The MPL W515L mutation was found in 4 patients and the MPL W515A mutation was detected in 1 patient. These 5 patients were diagnosed with JAK2 V617F-negative ET, and they accounted for 12.5% of patients with JAK2 V617F-negative ET. The patients with MPL W515-positive ET showed significantly lower hemoglobin levels and WBC counts than did patients with MPL W515-negative ET or JAK2 V617F-positive ET. CONCLUSIONS: MPL W515 mutation is a useful diagnostic marker for JAK2 V617F-negative MPNs and it is associated with specific hematologic characteristics such as lower hemoglobin levels and WBC counts.
Subject(s)
Humans , Janus Kinase 2 , Leukemia , Polycythemia Vera , Primary Myelofibrosis , Real-Time Polymerase Chain Reaction , Thrombocythemia, EssentialABSTRACT
BACKGROUND: Calreticulin (CALR) mutations were recently discovered in patients with myeloproliferative neoplasms (MPNs). We studied the frequency and type of CALR mutations and their hematological characteristics. METHODS: A total of 168 MPN patients (36 polycythemia vera [PV], 114 essential thrombocythemia [ET], and 18 primary myelofibrosis [PMF] cases) were included in the study. CALR mutation was analyzed by the direct sequencing method. RESULTS: CALR mutations were detected in 21.9% of ET and 16.7% of PMF patients, which accounted for 58.5% and 33.3% of ET and PMF patients without Janus kinase 2 (JAK2) or myeloproliferative leukemia virus oncogenes (MPL) mutations, respectively. A total of five types of mutation were detected, among which, L367fs*46 (53.6%) and K385fs*47 (35.7%) were found to be the most common. ET patients with CALR mutation had lower leukocyte counts and ages compared with JAK2-mutated ET patients. CONCLUSION: Genotyping for CALR could be a useful diagnostic tool for JAK2-or MPL-negative ET or PMF patients. CALR mutation may be a distinct disease group, with different hematological characteristics than that of JAK2-positive patients.
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Amino Acid Sequence , Base Sequence , Calreticulin/genetics , DNA Mutational Analysis , Exons , Janus Kinase 2/genetics , Leukocyte Count , Molecular Sequence Data , Mutation , Myeloproliferative Disorders/diagnosis , Receptors, Thrombopoietin/geneticsABSTRACT
We report on a 2-year-old girl who developed autoimmune hemolytic anemia, which occurred with minimal change nephrotic syndrome 3 months after umbilical cord blood transplantation for acute megakaryocytic leukemia. Because the disease is regarded as chronic graft versus host disease and developed while taking cyclosporine medication, she was treated with methylprednisolone 2 mg/kg/day. However, hemolysis and proteinuria were refractory to steroid treatment. One week after starting methylprednisolone, mycophenolate mofetil was added. Hemolysis and proteinuria showed improvement after 2 weeks of mycophenolate mofetil medication.