Pseudohyperphosphatemia in multiple myeloma: Removal of interfering paraproteins.
BackgroundMultiple myeloma patients may present with spuriously elevated serum phosphate levels resulting from the presence of paraproteins interfering in the phosphomolybdate UV assay. If this phenomenon is not recognized, patients possibly receive unnecessary treatments. This short report highlights the existence of paraprotein-related pseudohyperphosphatemia, and aims to provide accessible solutions to eliminate this interference.Material and MethodsIn a patient known with IgG multiple myeloma and unexplained hyperphosphatemia, the correlation between serum phosphate levels (phosphomolybdate UV assay) and IgG concentrations (immunoturbidimetry) was evaluated. To investigate the effect of the paraprotein on phosphate levels, phosphate was measured in one serum sample before and after protein removal by either dilution, protein precipitation with sulfosalicylic acid or zinc sulphate, or ultrafiltration.ResultsA patient with multiple myeloma presented with an unexplained hyperphosphatemia which correlated positively with serum IgG concentrations. As serum dilution normalized the phosphate level, it was hypothesized that precipitation of the paraprotein during the assay reaction interfered with the measurement and resulted in pseudohyperphosphatemia. Protein removal by precipitation with sulfosalicylic acid or zinc sulphate efficiently reduced the IgG level below the detection limit but did not result in a reliable phosphate measurement. Successful removal of proteins and a serum phosphate level that matched the patient's other biochemistry parameters and clinical condition were obtained by ultrafiltration.ConclusionParaproteins can interfere with the reaction components in the phosphomolybdate UV assay and result in pseudohyperphosphatemia. If the presence of this phenomenon is established, a reliable phosphate concentration can be obtained after ultrafiltration of the sample.
8
- 10.1016/j.cca.2014.11.028
- Dec 6, 2014
- Clinica Chimica Acta
84
- 10.1179/acb.2004.039
- Oct 1, 2004
- Acta Clinica Belgica
1
- 10.1016/j.amjmed.2019.10.022
- Nov 9, 2019
- The American Journal of Medicine
5
- 10.1002/ccr3.2264
- Jun 14, 2019
- Clinical Case Reports
2
- 10.1093/labmed/lmad012
- Mar 21, 2023
- Laboratory Medicine
15
- 10.5049/ebp.2007.5.2.131
- Dec 1, 2007
- Electrolytes & Blood Pressure : E & BP
18
- 10.1373/clinchem.2009.136895
- Jun 1, 2010
- Clinical Chemistry
- Research Article
51
- 10.2460/javma.229.8.1282
- Oct 15, 2006
- Journal of the American Veterinary Medical Association
To evaluate effects of 2 commercially available colostrum replacement products on serum IgG and total protein concentrations in dairy calves. Prospective clinical trial. 84 Holstein bull calves from a single dairy. Calves were randomly assigned to be given 4 quarts of colostrum (group 1; n = 21), 2 packages of a colostrum replacement product (product A; group 2; 21), 1 package of a different colostrum replacement product (product B; group 3; 21), or 2 packages of product B (group 4; 21). Treatments were given within 3 hours after birth, and blood samples were collected 24 hours later and submitted for determination of serum total protein and IgG concentrations. Group 1 calves had significantly higher serum total protein and IgG concentrations than did calves in the other 3 groups. However, the percentage of calves with adequate passive transfer (ie, serum IgG concentration > 1,000 mg/dL) was not significantly different among groups 1 (90%), 3 (81%), and 4 (95%). In contrast, only 10% of calves in group 2 had adequate passive transfer. It was predicted that calves fed product B that had serum total protein concentrations > 5.2 g/dL would have serum IgG concentrations > 1,000 mg/dL at least 90% of the time. Results indicated that product B could be considered as an alternative to colostrum in dairy calves, but product A failed to routinely provide adequate serum IgG concentrations when fed according to label directions.
- Research Article
32
- 10.1186/s12917-014-0178-7
- Aug 15, 2014
- BMC Veterinary Research
BackgroundEstimation of the quantity of colostral IgG or serum IgG absorbed following ingestion of colostrum by calves is essential for monitoring the effectiveness of colostrum feeding practices on dairy farms. Milk total solids concentrations determination is a critical part of quality assessment of nonsaleable whole milk prior to feeding to calves. To date, on-farm methods to assess colostral IgG, serum IgG or milk total solids concentrations have been performed separately with various instruments. The objective of this study was to evaluate the diagnostic performance of a single electronic, hand-held refractometer for assessing colostral and serum IgG concentrations and milk total solids in dairy cattle. Colostral IgG, serum IgG and milk total solids concentrations were determined by the refractometer. Corresponding analysis of colostral and serum IgG concentrations were determined by radial immunodiffusion (RID) while milk total solids were determined by spectrophotometry. Sensitivity and specificity of the refractometer for colostrum and serum samples were calculated as determined by RID. Sensitivity and specificity of the refractometer for milk samples was calculated as determined by spectrophotometry.ResultsThe sensitivity of the refractometer was 1 for colostral IgG, serum IgG and milk total solids determinations. Specificity of the refractometer was 0.66, 0.24 and 0 for colostral IgG, serum IgG and milk total solids determinations, respectively. The refractometer underestimated colostral IgG, serum IgG and milk total solids concentrations compared to the concentrations determined by RID or spectrophotometry.ConclusionsThe refractometer was an acceptable, rapid, convenient on-farm method for determining colostral IgG and milk total solids. The refractometer was not an acceptable method for determination of serum IgG concentrations as it severely underestimated the serum IgG concentrations.
- Research Article
- 10.3760/cma.j.issn.0254-1416.2012.02.007
- Feb 20, 2012
- Chinese Journal of Anesthesiology
Objective To investigate the effect of tertamethylpyrazine on perioperative humoral immune function in patients required for autologous blood transfusion.Methods Sixty ASA Ⅰ or Ⅱ patients aged 20-60 yr weighing 50-75 kg undergoing elective spinal surgery were randomly divided into 2 groups ( n =30 each):test group and control group.In test group,tertamethylpyrazine 2 mg/kg was infused intravenously over 5 min at 30 min before the autologous blood was collected.Tertamethylpyrazine was added to the heparinized saline and washing saline at the same time (25 mg per 500 ml) until the final concentration reached 0.005 %.Tertamethylpyrazine was not given in control group.Venous blood samples were taken before anesthesia induction (T0) and at 1 h after operation (T1),and on day 1 and 5 after operation (T2.3) for measurement of serum IgG and IgM concentrations by ELISA.The operation time,intraoperative blood loss and amount of salvaged blood reinfused were recorded.Results There was no significant difference in the operation time,intraoperative blood loss and amount of salvaged blood reinfused between the two groups (P > 0.05).Compared with the baseline value at T0,serum IgG and IgM concentrations were significantly decreased at T1-3 in control group and the serum IgG concentration was significantly decreased at T1.2 in test group ( P < 0.05 or 0.01 ).The serum IgG concentration at T2.3 and serum IgM concentration at T1-3 were significantly higher in test group than in control group ( P < 0.05 or 0.01 ).Conclusion Tertamethylpyrazine can reduce humoral immunosuppression to some extent and improve the balance of humoral immunity in patients required for autologous blood transfusion. Key words: TETRAMETHYLPYRAZINE; Blood transfusion, autologous; Antibody formation
- Research Article
16
- 10.2460/javma.1989.195.01.64
- Jul 1, 1989
- Journal of the American Veterinary Medical Association
SUMMARY Immunoglobulin G, IgM, and IgA concentrations were measured in serum collected from 36 Standardbred mares within 12 hours of foaling, in colostrum collected within 6 hours of foaling, and in serum collected from foals 24 to 48 hours after birth. In serum collected from mares after parturition, mean concentrations of IgG, IgM, and IgA were 2,463.9 ± 1,337.3 mg/dl, 136.4 ± 218 mg/dl, and 305.2 ± 237.5 mg/dl, respectively. In serum from foals, mean concentrations of IgG, IgM, and IgA were 1,953.3 ± 1,635 mg/dl, 33.8 ± 30.4 mg/dl, and 58.4 ± 42.2 mg/dl, respectively. In colostrum, mean concentrations of IgG, IgM, and IgA were 8,911.9 ± 6,282.2 mg/dl, 957 ± 1088.1 mg/dl, and 122.9 ± 77.3 mg/dl, respectively. The IgG concentrations in foal serum were poorly correlated with IgG concentrations in colostrum (r = 0.462, P < 0.01). Correlations of IgM or IgA concentrations in serum from foals with IgM or IgA concentrations in colostrum and correlations of IgG concentrations in serum from mares with those in colostrum were not significant (P < 0.01). Of 36 foals, 1 (2.8%) had a serum IgG concentration < 400 mg/dl. Of 36 foals monitored for 4 months, 6 developed infectious respiratory tract disease requiring antimicrobial therapy at ages varying from 55 to 113 days; these infections were probably not related to failure or partial failure of passive transfer of antibody.
- Research Article
4
- 10.1016/j.livsci.2010.06.008
- Jul 9, 2010
- Livestock Science
Effect of dietary supplementation of β-1,3–1,6-glucan on reproductive performance and immunity of New Zealand White does and their pups
- Research Article
33
- 10.1016/j.yebeh.2004.11.017
- Jan 29, 2005
- Epilepsy & Behavior
Serum IgA, IgG, and IgM concentrations in patients with epilepsy and matched controls: a cohort-based cross-sectional study
- Research Article
4
- 10.1023/a:1014431819413
- Jan 1, 2002
- Journal of clinical immunology
Serum concentrations of immunoglobulins IgG, IgG1, and IgG2 were determined in 62 Finnish subjects who were also typed for Gm(n) allele of IgG2 and R131 and H131 alleles of the Fcy receptor IIa. Statistically significant G2m-allotype-associated differences in serum concentrations of IgG2 were found; the mean concentration of IgG2 was high in Gm(n)-positive homozygotes (3.9 g/liter) and low in Gm(n)-negative individuals (2.6 g/liter; P = 0.0036), which is in accordance with previous reports. Contrary to an earlier report, no statistically significant R131/ H131-allotype-associated differences were found in serum concentrations of IgG2, not even in the case where the IgG2 concentration was calculated relative to the IgGI or IgG concentration (IgG2/IgG1 or IgG2/IgG). The gene frequencies of R131 and H131 alleles were 0.516 and 0.484, respectively, which did not differ significantly from those reported earlier for Finnish or other Caucasian populations.
- Research Article
3
- 10.1016/0300-9629(72)90121-1
- Jun 1, 1972
- Comparative Biochemistry and Physiology -- Part A: Physiology
Seasonal variations in serum concentration and half-life of hedgehog IgG2
- Research Article
9
- 10.3168/jdsc.2022-0236
- Oct 8, 2022
- JDS Communications
The aim of the present study was to describe the dynamics of serum IgG (determined with radial immunodiffusion) and total protein (TP; determined with refractometry) concentrations during the first 16 d of life. Secondary objectives were to evaluate the transfer of passive immunity (TPI) classification at d 1 of life as a conditional factor for the aforementioned dynamics, and to describe over time changes on calves' TPI classification. At a commercial raising operation, 36 calves (19 Holstein, 17 Jersey) were sampled immediately after arrival (d 1) and at d 4, 8, 12 and 16 of life, for serum IgG and TP concentration, and hematocrit determination (HCT). Transfer of passive immunity was categorized based on serum IgG (IgG-Poor: IgG <18 g/L; IgG-Good: IgG 18 to <25 g/L; IgG-Excellent: IgG ≥25 g/L) and TP concentrations (TP-Poor: <5.8 g/dL; TP-Good: 5.8 to <6.2 g/dL; TP-Excellent: ≥6.2 g/dL). Multiple linear regression was used to evaluate serum IgG and TP changes over time, considering the effects of time after birth, breed, HCT, and TPI classification at d 1 of life. At d 1, median serum IgG and TP concentrations were 29.9 g/L and 6.3 g/dL, respectively (interquartile ranges: 21.3–42.3 g/L and 5.6–6.7 g/dL, respectively). Dynamics of serum IgG and TP concentrations were conditional to TPI at d 1 of life. Serum IgG concentration declined over time for IgG-Excellent and IgG-Good calves (18.1 and 4.6 g/L, respectively), but remained constant for IgG-Poor calves. Serum TP concentration declined over time in the 3 TPI groups but it was more marked for TP-Excellent (27%) and TP-Good (19%) than for TP-Poor (14%) calves. At d 1, 83.3% of the calves were classified as IgG-Excellent or IgG-Good, whereas 77.8, 55.6, 41.7, and 58.3% of calves were classified within these categories at d 4, 8, 12, and 16 of life, respectively. Similarly, at d 1, 66.7% of calves were classified as TP-Excellent or TP-Good, whereas 47.2, 36.1, 25.0, and 2.8% were classified within these categories at d 4, 8, 12, and 16 of life, respectively. In summary, our results indicate that serum IgG and TP concentrations decline over 16 d of life, and the decline is associated with TPI classification at d 1 of life. Further studies are needed to determine the biological implications of serum IgG and TP decline after d 1 of life, and to elucidate the factors determining the different dynamics. Our results suggest that current thresholds for TPI classification should be interpreted carefully when the age of calves is unknown or outside the age range used to define those thresholds (>24 h to 7 d).
- Research Article
4
- 10.2460/ajvr.1984.45.09.1812
- Sep 1, 1984
- American Journal of Veterinary Research
SUMMARY Determinations were made by laser nephelometry of serum and csf immunoglobulin (Ig) G concentrations in Suffolk sheep with naturally occurring scrapie. The serum IgG concentrations in 3 sheep with confirmed or suspected scrapie were between 2,140 and 3,290 mg of IgG/100 ml, and the csf values were between < 10 and 75 mg of IgG/100 ml. In 8 clinically healthy (control) sheep, serum IgG concentrations were 2,647 to 7,380 mg/100 ml and csf IgG concentrations were between 0 (undetectable) and 162 mg/100 ml. A sheep with pulmonary adenomatosis had 1,445 mg of IgG/100 ml of serum. The results indicated that neither serum nor csf IgG concentrations were increased in sheep with naturally occurring infection with scrapie and that the severity of the disease did not correspond with the IgG concentration.
- Research Article
7
- 10.3389/fonc.2023.1123029
- Feb 8, 2023
- Frontiers in Oncology
The analysis of the immunogenetic background of multiple myeloma (MM) has proven key to understanding disease ontogeny. However, limited information is available regarding the immunoglobulin (IG) gene repertoire in MM cases carrying different heavy chain isotypes. Here, we studied the IG gene repertoire in a series of 523 MM patients, of whom 165 and 358 belonged to the IgA and IgG MM groups, respectively. IGHV3 subgroup genes predominated in both groups. However, at the individual gene level, significant (p<0.05) differences were identified regarding IGHV3-21 (frequent in IgG MM) and IGHV5-51 (frequent in IgA MM). Moreover, biased pairings were identified between certain IGHV genes and IGHD genes in IgA versus IgG MM. Turning to the imprints of somatic hypermutation (SHM), the bulk of rearrangements (IgA: 90.9%, IgG: 87.4%) were heavily mutated [exhibiting an IGHV germline identity (GI) <95%]. SHM topology analysis disclosed distinct patterns in IgA MM versus IgG MM cases expressing B cell receptor IG encoded by the same IGHV gene: the most pronounced examples concerned the IGHV3-23, IGHV3-30 and IGHV3-9 genes. Furthermore, differential SHM targeting was also identified between IgA MM versus IgG MM, particularly in cases utilizing certain IGHV genes, alluding to functional selection. Altogether, our detailed immunogenetic evaluation in the largest to-date series of IgA and IgG MM patients reveals certain distinct features in the IGH gene repertoires and SHM. These findings suggest distinct immune trajectories for IgA versus IgG MM, further underlining the role of external drive in the natural history of MM.
- Research Article
15
- 10.2460/ajvr.1985.46.11.2294
- Nov 1, 1985
- American Journal of Veterinary Research
SUMMARY A prospective study was performed to determine the incidence and associated maternal and managemental factors of failure of passive transfer (fpt) in foals on a breeding farm. The zinc sulfate turbidity test (zstt) and latex agglutination test (lat) were compared for accuracy in estimating serum immunoglobulin (Ig)G of foals, as determined by single radial immunodiffusion (srid). Complete past and present foaling histories of 136 Standardbred mares were obtained. All foalings were witnessed by farm attendents, and colostral samples were collected from mares within 2 hours after parturition. Foals that did not rise and nurse were supplemented with colostrum from the dam, using a bottle or nasogastric tube. Serum samples were prepared from foals and mares between 24 and 36 hours after parturition, and from some mares 45 to 90 days before parturition. Serum IgG concentrations of mares and foals and colostral whey were determined, using srid. Serum IgG also was estimated in foals, using zstt and a commercially available lat. Four of the 136 foals (2.9%) had fpt (serum IgG ≤ 400 mg/dl), Serum IgG concentrations in foals significantly correlated with colostral IgG (P < 0.001). A significantly larger proportion of foals with fpt were bottle-fed their colostrum (P < 0.01). Month of parturition, mare age, parity, number of barren seasons, incidence of assisted births or retained placenta, or prepartum serum IgG concentrations did not significantly affect colostral IgG concentrations or serum IgG concentrations in foals. As serum IgG concentrations in foals decreased and as colostral IgG concentrations decreased, the proportion of mares that prelactated significantly (P < 0.01) increased, A significant positive correlation was found between postpartum serum IgG and colostral IgG in mares that did not prelactate (P < 0.05). Immunization of mares for salmonellosis during gestation was positively correlated with higher colostral IgG concentrations (P < 0.05). A significant agreement was found between zstt, lat, and srid for estimation of serum IgG concentrations in foals (P < 0.001). For determination of serum IgG concentrations in foals, zstt results highly correlated with srid results; however, lat results were significantly more accurate for estimation of serum IgG concentrations ≤ 400 mg/dl (P < 0.001) than were zstt results.
- Research Article
17
- 10.1080/00480169.2011.627063
- Jan 1, 2012
- New Zealand Veterinary Journal
AIMS: To study the occurrence and spatial distribution of Shiga toxin-producing Escherichia coli (STEC) O157 in calves less than 1-week-old (bobby calves) born on dairy farms in the North Island of New Zealand, and to determine the association of concentration of IgG in serum, carcass weight, gender and breed with occurrence of E. coli O157 in these calves. METHODS: In total, 309 recto-anal mucosal swabs and blood samples were collected from bobby calves at two slaughter plants in the North Island of New Zealand. The address of the farm, tag number, carcass weight, gender and breed of the sampled animals were recorded. Swabs were tested for the presence of E. coli O157 using real time PCR (RT-PCR). All the farms were mapped geographically to determine the spatial distribution of farms positive for E. coli O157. K function analysis was used to test for clustering of these farms. Multiplex PCR was used for the detection of Shiga toxin 1 (stx1), Shiga toxin 2 (stx2), E. coli attaching and effacing (eae) and Enterohaemolysin (ehxA) genes in E. coli O157 isolates. Genotypes of isolates from this study (n = 10) along with human (n = 18) and bovine isolates (n = 4) obtained elsewhere were determined using bacteriophage insertion typing for stx encoding. RESULTS: Of the 309 samples, 55 (17.7%) were positive for E. coli O157 by RT-PCR and originated from 47/197 (23.8%) farms. E. coli O157 was isolated from 10 samples of which seven isolates were positive for stx2, eae and ehxA genes and the other three isolates were positive for stx1, stx2, eae and ehxA. Bacteriophage insertion typing for stx encoding revealed that 12/18 (67%) human and 13/14 (93%) bovine isolates belonged to genotypes 1 and 3. K function analysis showed some clustering of farms positive for E. coli O157. There was no association between concentration of IgG in serum, carcass weight and gender of the calves, and samples positive for E. coli O157, assessed using linear mixed-effects models. However, Jersey calves were less likely to be positive for E. coli O157 by RT-PCR than Friesian calves (p = 0.055). CONCLUSIONS: Healthy bobby calves are an asymptomatic reservoir of E. coli O157 in New Zealand and may represent an important source of infection for humans. Carriage was not associated with concentration of IgG in serum, carcass weight or gender.
- Abstract
6
- 10.1016/j.cca.2019.03.920
- May 15, 2019
- Clinica Chimica Acta
QIP-MS: A specific, sensitive, accurate, and quantitative alternative to electrophoresis that can identify endogenous m-proteins and distinguish them from therapeutic monoclonal antibodies in patients being treated for multiple myeloma
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11
- 10.1016/j.pathol.2019.04.002
- Jun 25, 2019
- Pathology
Heavy/light chain assay in the monitoring of multiple myeloma
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