OBJECTIVE: To analyze the clinical features and laboratory characteristics of patients with cold agglutinin disease (CAD)/cold agglutinin syndrome (CAS) who were positive for acidified-serum lysis test (Ham test), and to compare them with Ham test negative CAD/CAS patients and paroxysmal nocturnal hemoglobinuria (PNH) patients, in order to provide references for the differential diagnosis of these diseases. METHODS: 53 patients diagnosed with CAD/CAS and 67 patients diagnosed with classic PNH in our hospital from January 2015 to December 2020 were retrospectively analyzed. The patients were grouped according to clinical diagnosis and results of cold agglutinin test (CAT), direct antiglobulin test (DAT), Ham test and PNH clone detection. The clinical and laboratory characteristics of each group were compared. RESULTS: The patients were grouped as follows: Ham^- CAD/CAS group, CAD/CAS patients negative for Ham test (n=36); Ham⁺ CAD/CAS group, CAD/CAS patients positive for Ham test (n=17); classic PNH group (n=67). Compared with the classic PNH group, the Ham⁺ CAD/CAS group had a higher median age (P =0.024), weaker positivity of Ham test, higher positive rates of CAT and DAT, and lower positive rate of PNH clone detection (all P <0.001). The proportions of patients with splenomegaly and cyanosis in Ham⁺ CAD/CAS group were significantly higher than those in classic PNH group (P =0.002 and P <0.001). Ham⁺ CAD/CAS group displayed lower red blood cell count (RBC) and lactate dehydrogenase (LDH) level (P =0.007 and P <0.001), and higher mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and indirect bilirubin (IBIL) level (P =0.003, P =0.004 and P =0.006) than those in classic PNH group. The levels of serum complement C3 and C4 in Ham⁺ CAD/CAS group were lower than those in classic PNH group (P =0.001 and P <0.001). The positive rate of urinary occult blood in Ham⁺ CAD/CAS group was lower than that in classic PNH group (P =0.010). The clinical and laboratory characteristics of Ham⁺ CAD/CAS group were similar to those of Ham^- CAD/CAS group, except for median age, hemoglobin (Hb), MCHC, mean corpuscular volume (MCV), reticulocyte ratio (Ret), Ham test results, DAT positive types, and proportion of splenomegaly. CONCLUSION Some clinical features and laboratory indicators of CAD/CAS patients with positive results of Ham test are different from those of classic PNH patients, but relatively similar to those of CAD/CAS patients with negative results of Ham test. These results may provide a reference for differential diagnosis of related diseases.
Humans ; Anemia, Hemolytic, Autoimmune/blood* ; Retrospective Studies ; Hemoglobinuria, Paroxysmal/diagnosis* ; Female ; Male ; Coombs Test ; Diagnosis, Differential ; Middle Aged ; Adult

OBJECTIVE: To investigate the clinical features and laboratory characteristics of primary autoimmune hemolytic anemia (AIHA) patients with negative results of direct antiglobulin test (DAT) by tube test but positive results by microcolumn gel assay, in order to provide references for the diagnosis of these patients. METHODS: 59 patients diagnosed with primary AIHA in our hospital from January 2015 to December 2020 were retrospectively analyzed. According to the results of tube test and microcolumn gel assay, the cases were divided into 3 groups, and the clinical and laboratory characteristics of each group were compared. RESULTS: The cases were grouped as follows: Group I, cases with negative results by both methods of DAT (n=5); Group II, cases with negative results by tube test but positive results by microcolumn gel assay (n=26); Group III, cases with positive results by both methods of DAT (n=28). There was no significant difference in age and sex between Group II and other groups, whereas the positive rate of anti-IgG + anti-C3d of Group II was lower than that in Group III (P=0.015). The main clinical manifestations of Group II were chest tightness, shortness of breath, fatigue, as well as yellow skin and sclera or dark urine, but the incidence rate of these symptoms was not significantly different from other groups. Anemia related indexes in Group II such as red blood cell (RBC) count and hemoglobin (Hb) were lower than the reference intervals, but there was no significant difference compared with other groups. Hemolysis related indexes in Group II such as reticulocyte (Ret) ratio, indirect bilirubin (IBIL), lactate dehydrogenase (LDH) and free-hemoglobin (F-Hb) were higher than the reference intervals, and the latter two items were signficantly higher than those in Group I (P=0.031 and P=0.036). Serum complement C3 and C4 in Group II were higher than those in Group III (P=0.010 and P=0.037). CONCLUSION Anemia severity of primary AIHA patients who were negative of DAT by tube test but positive by microcolumn gel assay was similar to those with negative or positive results by both DAT methods, but the mechanism and degree of complement system involved in hemolysis might be different. Results above may be helpful for laboratory diagnosis of this kind of patients.
Anemia, Hemolytic, Autoimmune/diagnosis* ; Bilirubin ; Complement C3 ; Coombs Test/methods* ; Erythrocytes ; Hemolysis ; Humans ; Lactate Dehydrogenases ; Negative Results ; Retrospective Studies

COVID-19 ; Humans ; Inflammation/genetics* ; Lung ; Pneumonia ; SARS-CoV-2 ; Serologic Tests

OBJECTIVE: To study the serological detection characteristics and antibody specific distribution of hemolytic disease of the newborn (HDN) caused by irregular antibodies through retrospective case analysis. METHODS: A total of 3 047 suspected cases of HDN were submitted by the Neonatal Department of our hospital from January 2014 to December 2019. Non ABO-HDN cases confirmed in our laboratory were taken as the research objects, while some cases of ABO-HDN were randomly selected as control. Disease-causing antibody specificity, serological detection characteristics, total bilirubin change trend and gender ratio of non ABO-HDN patients were explored. RESULTS: Sixty-seven cases of non ABO-HDN were confirmed from the suspected cases of HDN, Among which 45 males and 22 females were detected with the positive rate 1.48% and 0.72%, respectively. The mothers of 65 cases had two or more pregnancies. The detected irregular antibodies were mainly involved with Rh system, MNS system, Kidd system and Lewis system, among which Rh system accounted for 88.07% of the total antibody detection rate. Compared with that of ABO-HDN patients, the total bilirubin of non ABO-HDN patients developed more rapidly with a higher peak and a longer duration (P<0.001). In terms of serological detection, the positive rate of non ABO-HDN direct antibody test was 97.01%, which was higher than 47.00% of ABO-HDN (P<0.001), and the agglutination strength was often ≥ 2+, but there were still weak positive or negative cases of direct antibody test. CONCLUSION Non ABO-HDN caused by irregular antibodies mostly occurs in fetuses whose mothers experience multiple pregnancies, and the number of males is more than females. The irregular antibodies detected are mainly attributed to Rh system. The peak value of bilirubin in non ABO-HDN patients is higher and lasts longer than that in ABO-HDN patients. Direct antiglobulin test may be used to roughly distinguish ABO-HDN from non ABO-HDN.
ABO Blood-Group System ; Blood Group Incompatibility ; Coombs Test ; Erythroblastosis, Fetal ; Female ; Humans ; Infant, Newborn ; Male ; Pregnancy ; Retrospective Studies

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions. Although viral reactivation is associated with DRESS syndrome, its role in TEN remains unclear. An 80-year-old woman visited our hospital because of fever and skin eruption. DRESS syndrome was diagnosed and was thought to caused by the use of the drug allopurinol. She was treated by discontinuation of the drug and administration of systemic steroids. She recovered from DRESS syndrome and was discharged from the hospital with tapering doses of steroids prescribed. One week after discharge, she visited our hospital again as the skin rash recurred and oral pain as well as oral and ocular mucosal lesions developed. In addition to the skin rash, blisters and Nikolsky's sign that were different from the skin lesions present in the previous DRESS syndrome were observed. Unlike those in DRESS syndrome, the viral serological test results were positive for anti-cytomegalovirus (CMV) IgM and CMV polymerase chain reaction. Therefore, it was thought that TEN was due to reactivation of CMV and she was treated this with ganciclovir and intravenous immunoglobulin. Here, we report a case of TEN caused by viral reactivation after DRESS syndrome developed after use of allopurinol which recovered after steroid treatment.
Aged, 80 and over ; Allopurinol ; Blister ; Cytomegalovirus Infections ; Cytomegalovirus ; Drug Hypersensitivity Syndrome ; Eosinophilia ; Exanthema ; Female ; Fever ; Ganciclovir ; Humans ; Immunoglobulin M ; Immunoglobulins ; Polymerase Chain Reaction ; Serologic Tests ; Skin ; Steroids ; Stevens-Johnson Syndrome

OBJECTIVE: To Establish the shielding threshold value of TP antibody ELISA for unpaid blood donors, so as to shield true positive blood donors from returning to team management. METHODS: The real serological status of 517 samples with anti-TP ELISA reactivity was determined by confirmation test of Treponema pallidum particle agglutination (TPPA). The shielding threshold of TP antibody was preliminarily determined by using 99% specificity of ROC and 95% positive predictive value of percentile method, respectively. 283 TP antibody reactivity specimens routinely tested in our laboratory were selected to determine the applicability of the initial shielding values obtained by the two methods, and finally to determine the shielding threshold values of TP antibody donors. RESULTS: The specific S/CO values of reagent A 99% were 13.33-16.18, that of reagent B 99% was 6.34, that of reagent B 99% was 13.17-19.85, and that of 95% was 6.62. Empirical evidence: 99% specific threshold shielding true positive rates of reagents A and B were 100%, 95% positive expected value shielding true positive rates were 98.4%, 99%. Final determination of 99% specific shielding threshold as a low value of blood donors shielding threshold. The shielding limits of reagent A and B were 13.33 and 13.17. CONCLUSION The shielding threshold of TP antibody ELISA for blood donors established in this study can help to reduce the number of blood donors returning to team management.
Blood Donors ; Enzyme-Linked Immunosorbent Assay ; Humans ; Syphilis ; Syphilis Serodiagnosis ; Treponema pallidum

two exchange transfusions received 6 days after she was born. Her blood type was B, RhD+, and findings from antibody screening and identification tests showed strong reactivity (3+ to 4+) in all panel cells except in her autologous cells. Based on these results, we concluded that she had an alloantibody to a high-prevalence antigen. Anti-PP₁P(k) alloantibody with p phenotype was identified by additional serological tests in a foreign reference laboratory. To confirm the patient's p phenotype, polymerase chain reaction and sequencing of the A4GALT gene were performed on her blood sample. She was homozygous for c.301delG in the A4GALT gene, which finally confirmed that she had the anti-PP₁P(k) antibody with p phenotype. Fortunately, her anemia caused due to iron deficiency could be treated with iron supplementation without the need for any transfusion. However, it remains extremely difficult to find compatible red blood cells in such settings in Korea. Moreover, there has been very little research on the prevalence of the p phenotype in the Korean population. Therefore, additional research is needed on rare blood group antibodies and high-prevalence antigens, including anti-PP₁P(k) cases.]]>
Anemia ; Antibodies ; Blood Transfusion ; Erythrocytes ; Female ; Humans ; Intellectual Disability ; Iron ; Isoantibodies ; Korea ; Mass Screening ; P Blood-Group System ; Phenotype ; Polymerase Chain Reaction ; Prevalence ; Rehabilitation ; Serologic Tests ; Young Adult

Transfusion-related acute lung injury (TRALI) is defined as a new episode of acute lung injury that occurs during or within 6 hours of a completed transfusion, which is one of the leading causes of transfusion-related morbidity and mortality. We present a case of TRALI in a 29-year-old parturient with myelodysplastic syndrome scheduled for cesarean section. The parturient developed hypoxemia and dyspnea after preoperative transfusion of platelets following apheresis to eliminate a unit of leucocyte in order to correct thrombocytopenia. She underwent emergent caesarean section for fetal distress. After surgery, the chest radiograph showed diffuse haziness of both lung fields. Direct and indirect antiglobulin tests were negative, and hemolytic transfusion reaction was ruled out. Pro-BNP 347.3 pg/ml also excluded transfusion-associated circulatory overload. The parturient completely recovered after oxygen support for 2 days. It is important to recognize TRALI as soon as possible to minimize perioperative morbidity and mortality.
Acute Lung Injury* ; Adult ; Anoxia ; Blood Component Removal ; Cesarean Section ; Coombs Test ; Dyspnea ; Female ; Fetal Distress ; Humans ; Lung ; Mortality ; Myelodysplastic Syndromes* ; Oxygen ; Pregnancy ; Radiography, Thoracic ; Thrombocytopenia ; Transfusion Reaction

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, and is endemic in many Latin American countries. Diagnosis is based on serologic testing and the WHO recommends two or more serological tests for confirmation. Acidic ribosomal P protein of T. cruzi showed strong reactivity against positive sera of patients, and we cloned the protein after fragmenting it to enhance its antigenicity and solubility. Twelve positive sera of Chagas disease patients were reacted with the fragmented ribosomal P protein using western blot. Detection rate and density for each fragment were determined. Fragments F1R1, F1R2, and F2R1 showed 100% rate of detection, and average density scoring of 2.00, 1.67, and 2.42 from a maximum of 3.0, respectively. Therefore, the F2R1 fragment of the ribosomal P protein of T. cruzi could be a promising antigen to use in the diagnosis of Chagas disease in endemic regions with high specificity and sensitivity.
Blotting, Western ; Chagas Disease ; Clone Cells ; Diagnosis ; Humans ; Parasites ; Sensitivity and Specificity ; Serologic Tests ; Solubility ; Trypanosoma cruzi

Cysticercosis, a parasitic disease caused by Taenia solium metacestode (TsM), has a major global public health impact in terms of disability-adjusted life years. The parasite preferentially infects subcutaneous tissue, but may invade the central nervous system, resulting in neurocysticercosis (NC). NC is an important neglected tropical disease and an emerging disease in industrialized countries due to immigration from endemic areas. The prevalence of taeniasis in Korea declined from 0.3%–12.7% during the 1970s to below 0.02% since the 2000s. A survey conducted from 1993 to 2006 revealed that the percentage of tested samples with high levels of specific anti-TsM antibody declined from 8.3% to 2.2%, suggesting the continuing occurrence of NC in Korea. Modern imaging modalities have substantially improved the diagnostic accuracy of NC, and recent advances in the molecular biochemical characterization of the TsM cyst fluid proteome also significantly strengthened NC serodiagnosis. Two glycoproteins of 150 and 120 kDa that induce strong antibody responses against sera from patients with active-stage NC have been elucidated. The 150 kDa protein showed hydrophobic-ligand binding activities and might be critically involved in the acquisition of host-derived lipid molecules. Fasciclin and endophilin B1, both of which play roles in the homeostatic functions of TsM, showed fairly high antibody responses against calcified NC cases. NC is now controllable and manageable. Further studies should focus on controlling late-onset intractable seizures and serological diagnosis of NC patients infected with few worms. This article briefly overviews diagnostic approaches and discusses current issues relating to NC serodiagnosis.
Antibody Formation ; Central Nervous System ; Cyst Fluid ; Cysticercosis ; Developed Countries ; Diagnosis ; Emigration and Immigration ; Glycoproteins ; Humans ; Immunologic Tests ; Korea ; Neurocysticercosis ; Parasites ; Parasitic Diseases ; Prevalence ; Proteome ; Public Health ; Republic of Korea ; Seizures ; Serologic Tests ; Subcutaneous Tissue ; Taenia solium ; Taenia ; Taeniasis