OBJECTIVE: To analyze the results of prenatal diagnosis for fetuses with a high risk for sex chromosome aneuploidies (SCAs) indicated by non-invasive prenatal testing (NIPT), and to assess the influence of maternal chromosomal factors on the results of NIPT. METHODS: A retrospective analysis was conducted on the clinical data of 454 pregnant women with a high risk for SCAs indicated by NIPT undergoing invasive prenatal diagnosis at the Medical Genetics Center of Northwest Women's and Children's Hospital from January 2022 to September 2024. The data has included prenatal diagnosis indications, results, pregnancy outcomes, and the chromosomal results of pregnant women. RESULTS: Among the 454 women (including 10 with twin pregnancy) with a high risk for SCAs indicated by NIPT, 149 (including 4 twin cases) were diagnosed with SCAs through invasive prenatal diagnosis. These had included 47,XXX (37 cases), 47,XXY (56 cases), 47,XYY (29 cases), 45,X (1 case), 48,XXYY (1 case), mosaicism (20 cases), sex chromosome structural abnormalities (6 cases), and small-scale pathogenic copy number variations (3 cases). 383 pregnant women (including 7 with twin pregnancy) had accepted chromosomal karyotyping analysis. In total 49 cases of SCAs abnormalities were detected. Among them, 41 cases were pregnant women with SCAs but normal fetal chromosomes, which yielded a false positive rate for NIPT caused by maternal factors by 10.7%. In addition, 8 cases (including 1 twin case) had SCAs abnormalities in both the pregnant woman and the fetus. Among the 383 pregnant women, 129 cases (including 3 twin cases) of fetal SCAs were diagnosed, which yielded an overall positive predictive value (PPV) of NIPT for SCAs by 33.7% (129/383). With the 41 false positive cases caused by maternal SCAs abnormalities excluded, the PPV of NIPT for SCAs will be increased to 37.7% (129/342). Among the 454 pregnant women, twin pregnancies have accounted for 2.2% (10/454). Among the confirmed cases of SCAs abnormalities, twin cases accounted for 2.7% (4/149). Among the 383 pregnant women undergoing chromosomal karyotyping, twin cases accounted for 1.8% (7/383). Among the detected cases of chromosomal abnormalities, twin cases accounted for 2.0% (1/49). By calculation, the proportion of singleton pregnant women with a high risk for SCAs indicated by NIPT was approximately 32.1%, and the proportion of twin pregnant women was approximately 38.6%, indicating that twin pregnancies could increase the positive rate of NIPT. CONCLUSION NIPT can improve the screening efficiency for SCAs, but its PPV is limited. Therefore, pregnant women with a high risk for SCAs indicated by NIPT need to undergo invasive prenatal diagnosis for a definite diagnosis, and twin pregnancies can increase the positive rate of NIPT. The study confirmed that chromosomal abnormalities in pregnant women can significantly affect the accuracy of NIPT in detecting fetal SCAs. Therefore, when NIPT indicates SCAs abnormalities, it is recommended to simultaneously conduct chromosomal testing on the pregnant women. The combined application of chromosomal karyotyping analysis, fluorescence in situ hybridization, and copy number variation detection techniques can significantly improve the diagnostic accuracy for SCAs, especially for the detection of mosaicisms.
Humans ; Female ; Pregnancy ; Sex Chromosome Aberrations ; Adult ; Retrospective Studies ; False Positive Reactions ; Prenatal Diagnosis/methods* ; Noninvasive Prenatal Testing/methods* ; Aneuploidy ; Male ; Sex Chromosome Disorders/genetics*

OBJECTIVE: To retrospectively analyze the results of second-trimester serological prenatal screening and explore the factors which may influence the false-positive rate (FPR). METHODS: From January 2013 to December 2022, false-positive samples with follow-up outcomes from 632,825 second-trimester serological prenatal screening samples tested at Sichuan Provincial Maternity and Child Health Care Hospital were selected as the study group, while true-negative samples were 1 : 1 matched as the control group by propensity-score matching (PSM). Univariate and binary logistic regression models were used to analyze the influencing factors. This study was approved by the Medical Ethic Committee of Sichuan Provincial Maternity and Child Health Care Hospital (Ethic No. 20240607-270). RESULTS: The study and control groups were each matched with 305,998 cases. Univariate analysis showed that sampling season, the difference between ultrasound and gestational weeks calculated by last menstrual period (LMP), monthly median multiple of the median (mMoM) of alpha-fetoprotein (AFP), and monthly mMoM of free β -human chorionic gonadotropin (free β -hCG) were significantly different between the two groups (P < 0.05). Binary logistic regression analysis showed that Winter (OR = 0.938; 95%CI: 0.893 ~ 0.985), monthly AFP mMoM ≥ 1.11 (OR = 0.846; 95%CI: 0.761 ~ 0.941), monthly free β -hCG mMoM ≥ 0.89 (OR = 0.827; 95%CI: 0.737 ~ 0.929) are protective factors for FPR increase, whilst Spring (OR = 1.124; 95%CI: 1.072 ~ 1.179), Summer (OR = 1.121; 95%CI: 1.062 ~ 1.183), the difference between ultrasound and gestational weeks calculated by LMP of 8 ~ 14 days (OR = 1.319; 95%CI: 1.241 ~ 1.402), < 14 days (OR = 1.689; 95%CI: 1.542 ~ 1.850), monthly AFP mMoM of 0.90 ~ 0.94 (OR = 1.088; 95%CI: 1.046 ~ 1.131), and monthly free β -hCG mMoM of 1.05 ~ 1.10 (OR = 1.046; 95%CI: 1.000 ~ 1.094), ≥ 1.11 (OR = 1.062; 95%CI: 1.002 ~ 1.126) are risk factors for FPR increase. CONCLUSION Sampling season, difference between ultrasound and gestational weeks by LMP, monthly AFP mMoM, and monthly free β -hCG mMoM are risk factors for FPR during serological prenatal screening. Screening laboratories should look for the cause of abnormal FPR through such factors and adjust them accordingly.
Humans ; Female ; Pregnancy ; Propensity Score ; Pregnancy Trimester, Second/blood* ; Retrospective Studies ; China ; False Positive Reactions ; Adult ; Prenatal Diagnosis/methods* ; alpha-Fetoproteins/analysis* ; Logistic Models ; Chorionic Gonadotropin, beta Subunit, Human/blood*

Analysis of variance (ANOVA) is one of the most frequently used statistical methods in medical research. The need for ANOVA arises from the error of alpha level inflation, which increases Type 1 error probability (false positive) and is caused by multiple comparisons. ANOVA uses the statistic F, which is the ratio of between and within group variances. The main interest of analysis is focused on the differences of group means; however, ANOVA focuses on the difference of variances. The illustrated figures would serve as a suitable guide to understand how ANOVA determines the mean difference problems by using between and within group variance differences.
Analysis of Variance* ; False Positive Reactions ; Inflation, Economic

PURPOSE: False-positive (FP) results of fecal immunochemical tests (FITs) conducted in colorectal cancer (CRC) screening could lead to performing unnecessary colonoscopies. Hemorrhoids are a possible cause of FP FIT results; however, studies on this topic are extremely rare. We investigated whether hemorrhoids are associated with FP FIT results. MATERIALS AND METHODS: A retrospective study was conducted at a university hospital in Korea from June 2013 to May 2015. Of the 34547 individuals who underwent FITs, 3946 aged ≥50 years who underwent colonoscopies were analyzed. Logistic regression analysis was performed to determine factors associated with FP FIT results. RESULTS: Among 3946 participants, 704 (17.8%) showed positive FIT results and 1303 (33.0%) had hemorrhoids. Of the 704 participants with positive FIT results, 165 had advanced colorectal neoplasia (ACRN) and 539 had no ACRN (FP results). Of the 1303 participants with hemorrhoids, 291 showed FP results, of whom 81 showed FP results because of hemorrhoids only. Participants with hemorrhoids had a higher rate of FP results than those without hemorrhoids (291/1176, 24.7% vs. 248/2361, 10.5%; p<0.001). Additionally, the participants with hemorrhoids as the only abnormality had a higher rate of FP results than those experiencing no such abnormalities (81/531, 15.3% vs. 38/1173, 3.2%; p<0.001). In multivariate analysis, the presence of hemorrhoids was identified as an independent predictor of FP results (adjusted odds ratio, 2.76; 95% confidence interval, 2.24–3.40; p<0.001). CONCLUSION: Hemorrhoids are significantly associated with FP FIT results. Their presence seemed to be a non-negligible contributor of FP results in FIT-based CRC screening programs.
Aged ; Colonoscopy ; Colorectal Neoplasms/*diagnosis ; Confidence Intervals ; Early Detection of Cancer/methods ; False Positive Reactions ; Female ; *Hemorrhoids ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; *Occult Blood ; Odds Ratio ; Regression Analysis ; Republic of Korea ; Retrospective Studies ; Unnecessary Procedures

BACKGROUND: Specific IgE antibodies against the low-molecular-weight carbohydrate antigen that does not bridge IgE molecules on mast cells are not associated with clinical symptoms. Cross reactivity can be determined in allergen-specific IgE detection assays when the carbohydrate structures between pollen allergens and plant derived food allergens are similar; in such cases, false positive results for grain or legume allergens can be reported for pollen allergic patients who are not sensitized to those allergens. This phenomenon arises owing to the presence of cross-reactive carbohydrate determinants (CCDs). OBJECTIVE: This study aimed to assess the impact of CCD interference on the results for pollen allergen-specific IgE antibodies in the general adult population and to perform CCD inhibition tests evaluating the involvement of CCD on samples positive to pollen allergens. METHODS: Serum samples from 322 subjects were tested for IgE antibodies to pollens and CCD. The research subjects were given questionnaires about pollen allergic symptoms to help assess the presence of allergies. Allergen IgE antibodies for Japanese cedar, Japanese cypress, orchard grass, ragweed, MUXF, bromelain, horseradish peroxidase (HRP), and ascorbate oxidase (ASOD) were analyzed. RESULTS: It was observed that among individuals who tested positive to any of the pollen allergens, the positive ratio of CCD-specific IgE antibody was the highest for HRP (13.5%–50.0%). The results from the inhibition tests revealed that CCD was marginally present. Although IgE antibodies for cedar pollen did not react with CCD, IgE antibodies for Japanese cypress, orchard grass, and ragweed might be detected by the presence of CCD. CONCLUSION: The results of the inhibition tests revealed the obvious presence of CCD suggesting its involvement. Considering these findings, careful evaluation of patient IgE results should be performed for Japanese cypress, orchard grass, and ragweed.
Adult ; Allergens ; Ambrosia ; Antibodies ; Ascorbate Oxidase ; Asian Continental Ancestry Group ; Bromelains ; Cryptomeria ; Cupressus ; Dactylis ; Fabaceae ; False Positive Reactions ; Horseradish Peroxidase ; Humans ; Hypersensitivity ; Immunoglobulin E ; Mast Cells ; Plants ; Pollen ; Research Subjects ; Rhinitis, Allergic ; Rhinitis, Allergic, Seasonal

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Eating ; Esophagoscopy ; Esophagus ; diagnostic imaging ; surgery ; False Positive Reactions ; Foreign Bodies ; diagnosis ; diagnostic imaging ; Foreign-Body Migration ; diagnosis ; diagnostic imaging ; Humans ; Middle Aged ; Pharynx ; diagnostic imaging ; surgery ; Radiography ; Remission, Spontaneous ; Retrospective Studies ; Tomography, X-Ray Computed ; Young Adult

BACKGROUNDThe false positive in conventional syphilis serological test was found in patients with multiple myeloma (MM).

OBJECTIVETo investigate the relationship between the M-protein of patients with MM and the false positive in conventional syphilis serologic test.

METHODSThe M-protein of 68 MM cases was typed with immunofixation electrophoresis and 68 cases of MM were screened with non-specific and specific syphilis serologic tests, then the samples with syphilic serological positive were chosen and confirmed with immonobloting test, finally the relationship between M protein of MM and the false positive of syphilis serological test were analysed.

RESULTSFour out of 68 cases showed the positive in syphilis serological test and further were confimed to be false positive by immunoblotting test, the false positive rate was nearly 6%. The M-protein of MM patients in our hospital mostly possessed IgG, κ type, followed by IgA, κ type, light chain κ type. In general, κ : λ = 2.4 : 1. Among samples of 4 cases with syphilis serological positive 2 cases were of IgG and κ type, 1 case was of IgG, λ type, another 1 case was IgA, κ type.

CONCLUSIONThe M-protein of IgG and IgA types in MM patients results in syphilis serological false positive reaction. The clinicians and laboratorial technicians should pay a great attention to screen the MM patients for the false positive syphilis serological test so as to avoid the misdiagnosis and subsequent embarassment.

Diagnostic Errors ; False Positive Reactions ; Humans ; Immunoglobulin A ; classification ; Immunoglobulin G ; classification ; Multiple Myeloma ; diagnosis ; Myeloma Proteins ; metabolism ; Syphilis ; diagnosis ; Syphilis Serodiagnosis

OBJECTIVETo explore the effect of false positive signals during detection of BCR/ABL fusion gene by fluorescence in situ hybridization (FISH), and develop a method for calibration.

METHODSNormal specimens were mixed with BCR/ABL positive specimens in which presented signal pattern of 1-red-2-green-1-fusion (1R2G1F) using dual color dual fusion (DCDF) probes and 1-red-1-green-1-fusion (1R1G1F) using extra signal (ES) probes in different proportions. Mixed samples were detected using DCDF and ES probes. Results of DCDF probes, ES probe before calibration, ES probes after calibration and theoretical results were compared by binomial distribution in different proportions.

RESULTSThe rate of false positive signals has risen with increase of negative rate. A significant difference was found between theoretical proportion and results without calibration in negative level, 5%, 10% and 25% positive level (P<0.05). There was no significant difference between theoretical proportion and results without calibration in 50% and 90% positive level (P>0.05). Also there was no significant difference between theoretical proportion and calibrated results (P>0.05).

CONCLUSIONCalibration of FISH result can delimitate the effect of false positives, and can provide more reliable results in cases with low level positive rates.

Adult ; Calibration ; False Positive Reactions ; Female ; Fusion Proteins, bcr-abl ; genetics ; Humans ; In Situ Hybridization, Fluorescence ; methods ; standards ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; diagnosis ; genetics ; Young Adult

BACKGROUND/AIMS: To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. METHODS: A total of 107 volunteers were enrolled. All subjects underwent a 13C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. RESULTS: H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 +/- 646.7 and 604.3 +/- 594.3 mumol/L (p > 0.05), and pH was 3.37 +/- 1.64 and 2.82 +/- 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. CONCLUSIONS: HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.
Adult ; Antibodies, Monoclonal/*immunology ; Bacterial Proteins/*analysis/immunology ; Biomarkers/analysis ; Biopsy ; False Negative Reactions ; False Positive Reactions ; Female ; Gastritis, Atrophic/*diagnosis/microbiology ; Helicobacter Infections/*diagnosis/microbiology ; Helicobacter pylori/*enzymology/immunology ; Humans ; *Immunologic Tests ; Male ; Metaplasia ; Middle Aged ; Predictive Value of Tests ; Pyloric Antrum/*microbiology/pathology ; Reproducibility of Results ; Time Factors ; Urease/*analysis/immunology ; Workflow

No abstract available.
Bronchi/microbiology/pathology ; Coronavirus Infections/*microbiology/*pathology ; Delayed Diagnosis/*prevention & control ; Diagnosis, Differential ; Diagnostic Errors/*prevention & control ; False Positive Reactions ; Humans ; Male ; Middle Aged ; Reproducibility of Results ; Sensitivity and Specificity ; Specimen Handling/methods ; Sputum/*cytology/*microbiology