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Jerry A Katzmann

Publications and source records attributed to Jerry A Katzmann.

At least 19 recordsLinked to original sources
PubMed2006

Diagnosis of alpha-1-antitrypsin deficiency: An algorithm of quantification, genotyping, and phenotyping.

BACKGROUND: Laboratory testing in suspected alpha-1-antitrypsin (A1AT) deficiency involves analysis of A1AT concentrations and identification of specific alleles by genotyping or phenotyping. The purpose of this study was to define and evaluate a strategy that provides reliable laboratory evaluation of A1AT deficiency. METHODS: Samples from 512 individuals referred for A1AT phenotype analysis were analyzed by quantification, phenotype, and genotype. A1AT concentrations were measured by nephelometry. Phenotype analysis was performed by isoelectric focusing electrophoresis. The genotype assay detected the S and Z deficiency alleles by a melting curve analysis. RESULTS: Of the 512 samples analyzed, 2% of the phenotype and genotype results were discordant. Among these 10 discordant results, 7 were attributed to phenotyping errors. On the basis of these data we formulated an algorithm, according to which we analyzed samples by genotyping and quantification assays, with a reflex to phenotyping when the genotype and quantification results were not concordant. Retrospective analyses demonstrated that 4% of samples submitted for genotype and quantitative analysis were reflexed to phenotyping. Of the reflexed samples, phenotyping confirmed the genotype result in 85% of cases. In the remaining 15%, phenotyping provided further information, including identifying rare deficiency alleles and suggesting the presence of a null allele, and allowed for a more definitive interpretation of the genotype result. CONCLUSIONS: The combination of genotyping and quantification, with a reflex to phenotyping, is the optimal strategy for the laboratory evaluation of A1AT deficiency.

Algorithms↗
PubMed2006

Elevated serum IgG4 concentration in patients with primary sclerosing cholangitis.

OBJECTIVES: Biliary strictures, similar to primary sclerosing cholangitis (PSC), have been reported in patients with autoimmune pancreatitis, which is characterized by elevated serum IgG4 levels and responsiveness to corticosteroids. We sought to determine the frequency of elevated IgG4 in patients with PSC and to clinically compare PSC patients with elevated and normal IgG4 levels. METHODS: We measured serum IgG4 in 127 patients with PSC and 87 patients with primary biliary cirrhosis, as disease controls. Demographic, clinical, and laboratory characteristics were compared between the PSC groups with normal and elevated IgG4 (>140 mg/dL). RESULTS: Elevated IgG4 was found in 12 PSC patients (9%) versus one PBC patient (1.1%) (p= 0.017). Patients with elevated IgG4 had higher total bilirubin (p= 0.009), alkaline phosphatase (p= 0.01), and PSC Mayo risk score (p= 0.038), and lower frequency of IBD (p < 0.0001). Importantly, the time to liver transplantation was shorter in patients with elevated IgG4 (1.7 vs 6.5 yr, p= 0.0009). The type of biliary involvement (intrahepatic, extrahepatic, or both) and pancreatic involvement were similar in both groups. CONCLUSIONS: A small proportion of PSC patients had elevated serum IgG4. In these patients parameters of liver disease severity were more pronounced and time to liver transplantation was shorter, suggesting a more severe disease course. It is possible that this subset of patients behaves similarly to autoimmune pancreatitis patients with biliary strictures, and could potentially respond to corticosteroids. Testing PSC patients for IgG4 and treating those with elevated levels with corticosteroids in clinical trials should be considered.

Adult↗
PubMed2006

Immunoglobulin free light chains and solitary plasmacytoma of bone.

An abnormal serum immunoglobulin free light chain (FLC) ratio at diagnosis may identify risk of progression to myeloma in patients with solitary bone plasmacytoma (SBP). In the cohort of 116 patients, 43 have progressed to myeloma, with a median time to progression of 1.8 years. The FLC ratio was determined in all 116 patients on serum collected at time of diagnosis and was abnormal in 54 patients (47%). An abnormal FLC ratio was associated with a higher risk of progression to myeloma (P = .039). The risk of progression at 5 years was 44% in patients with an abnormal serum FLC ratio at diagnosis compared with 26% in those with a normal FLC ratio. One to 2 years following diagnosis, a persistent serum M protein level of 5 g/L (0.5 g/dL) or higher was an additional risk factor for progression. A risk stratification model was constructed using the 2 variables of FLC ratio and M protein level: patients with a normal FLC ratio at baseline and M protein level less than 5 g/L (0.5 g/dL) at 1 to 2 years following diagnosis (low risk, n = 31); with either risk factor abnormal (intermediate risk, n = 26); and with both an abnormal FLC ratio and M protein level of 5 g/L (0.5 g/dL) or higher (high risk, n = 18). The corresponding progression rates at 5 years were significantly different in the low, intermediate, and high groups: 13%, 26%, and 62%, respectively (P < .001).

Adult↗
PubMed2006

Prevalence of monoclonal gammopathy of undetermined significance.

BACKGROUND: The prevalence of monoclonal gammopathy of undetermined significance (MGUS), a premalignant plasma-cell disorder, among persons 50 years of age or older has not been accurately determined. We used sensitive laboratory techniques to ascertain the prevalence of MGUS in a large population in a well-defined geographic area. METHODS: We identified all living residents of Olmsted County, Minnesota, as of January 1, 1995. We obtained serum that remained after the performance of routine clinical tests at Mayo Clinic or asked subjects for whom such serum was unavailable to provide a sample. Agarose-gel electrophoresis was performed on all serum samples, and any serum sample with a discrete band of monoclonal protein or thought to have a localized band was subjected to immunofixation. RESULTS: Serum samples were obtained from 21,463 of the 28,038 enumerated residents 50 years of age or older (76.6 percent). MGUS was identified in 694 (3.2 percent) of these persons. Age-adjusted rates were higher in men than in women (4.0 percent vs. 2.7 percent, P<0.001). The prevalence of MGUS was 5.3 percent among persons 70 years of age or older and 7.5 percent among those 85 years of age or older. The concentration of monoclonal immunoglobulin was less than 1.0 g per deciliter in 63.5 percent and at least 2.0 g per deciliter in only 4.5 percent of 694 persons. The concentration of uninvolved immunoglobulins was reduced in 27.7 percent of 447 persons tested, and 21.5 percent of 79 tested had a monoclonal urinary light chain. CONCLUSIONS: Among residents of Olmsted County, Minnesota, MGUS was found in 3.2 percent of persons 50 years of age or older and 5.3 percent of persons 70 years of age or older.

Age Distribution↗
PubMed2006

Absolute values of immunoglobulin free light chains are prognostic in patients with primary systemic amyloidosis undergoing peripheral blood stem cell transplantation.

The immunoglobulin free light chain (FLC) is the precursor protein of amyloid in primary systemic amyloidosis (AL). Historically, the ability to monitor the amyloid protein precursor protein has been crude. We evaluated the utility of the FLC assay in a retrospective analysis of patients with AL undergoing peripheral blood stem cell transplantation (PBSCT). Ninety-three such patients had serial FLC measurements performed. The prognostic effects of the initial concentration and the extent of reduction of monoclonal FLC on survival were studied. There was a significantly higher risk of death in patients with higher baseline FLC (hazard ratio 2.6, P < .04). Baseline FLC correlated with serum cardiac troponin levels, and higher FLC levels were associated with more organs involved by amyloid, suggesting that high FLC levels may be associated with more advanced disease. The percent FLC reduction did not predict for survival, but the absolute level of FLC achieved after therapy did. Normalization of FLC level after PBSCT predicted for both organ response and complete hematologic response. Achievement of FLC response was a better predictor of survival than achievement of complete hematologic response or normalization of the FLC ratio. FLC measurements both before and after PBSCT are important predictors of patient outcome.

Adult↗
PubMed2006

Elimination of the need for urine studies in the screening algorithm for monoclonal gammopathies by using serum immunofixation and free light chain assays.

OBJECTIVE: To determine the relative diagnostic contribution of urine assays as part of the screening algorithm for monoclonal gammopathies. PATIENTS AND METHODS: We identified 428 patients with a monoclonal gammopathy and monoclonal urinary protein at initial diagnosis of plasma cell dyscrasia who had also undergone serum immunofixation and serum free light chain quantitation within 30 days of diagnosis. The laboratory results for serum protein electrophoresis, serum immunofixation, serum free light chain, urine protein electrophoresis, and urine immunofixation were reviewed. RESULTS: The patients had diagnoses of multiple myeloma, primary amyloid, monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, solitary plasmacytomas, and other less frequently detected monoclonal gammopathies. All 428 had a monoclonal urine protein, 85.7% had an abnormal serum free light chain kappa/lambda ratio, 80.8% had an abnormal serum protein electrophoresis, and 93.5% had an abnormal serum immunofixation result. All 3 serum assays were normal in only 2 patients, 1 of whom had monoclonal gammopathy of undetermined significance (idiopathic Bence Jones proteinuria) and 1 whose urine sample contained an intact monoclonal immunoglobulin but whose serum and subsequent urine samples showed no evidence of a monoclonal gammopathy. CONCLUSION: Discontinuation of urine studies and reliance on a diagnostic algorithm using only serum studies (protein electrophoresis, immunofixation, and free light chain quantitation) missed 2 (0.5%) of the 428 monoclonal gammopathies with urinary monoclonal proteins, and these 2 cases required no medical intervention.

Algorithms↗
PubMed2006

A comparison of morphologic features, flow cytometry, TCR-Vbeta analysis, and TCR-PCR in qualitative and quantitative assessment of peripheral blood involvement by Sézary syndrome.

The strengths and weaknesses of various laboratory methods for peripheral blood (PB) Sézary cell quantitation have not been compared rigorously. In this study, manual Sézary cell counting, qualitative and quantitative flow cytometry, T-cell receptor (TCR) Vbeta flow cytometry, and TCR polymerase chain reaction were performed on PB specimens from 11 patients with Sézary syndrome (SS), 9 with reactive erythroderma, 6 with mycosis fungoides, and 11 healthy control subjects. These methods identified neoplastic cells in more than 90% of SS cases. The diagnostic specificities of these tests varied; they were enhanced by applying criteria proposed by the International Society for Cutaneous Lymphoma. Comparison of sequentially analyzed specimens from 6 patients with SS revealed that although the absolute number of clonal cells was reduced, in some cases, these cells still constituted the vast majority of the CD4+ T-cell subset, suggesting that quantitative subset analysis might be sufficient to monitor changes in the PB tumor burden.

Adult↗
PubMed2005

Serum free light chain ratio is an independent risk factor for progression in monoclonal gammopathy of undetermined significance.

We hypothesized that the presence of monoclonal free kappa or lambda immunoglobulin light chains in monoclonal gammopathy of undetermined significance (MGUS), as detected by the serum free light chain (FLC) assay increases the risk of progression to malignancy. Of 1384 patients with MGUS from Southeastern Minnesota seen at the Mayo Clinic from 1960 to 1994, baseline serum samples obtained within 30 days of diagnosis were available in 1148. At a median follow-up of 15 years, malignant progression had occurred in 87 (7.6%) patients. An abnormal FLC ratio (kappa-lambda ratio < 0.26 or > 1.65) was detected in 379 (33%) patients. The risk of progression in patients with an abnormal FLC ratio was significantly higher compared with patients with a normal ratio (hazard ratio, 3.5; 95% confidence interval [CI], 2.3-5.5; P < .001) and was independent of the size and type of the serum monoclonal (M) protein. Patients with an abnormal serum FLC ratio, non-immunoglobulin G (non-IgG) MGUS, and a high serum M protein level (> or = 15 g/L) had a risk of progression at 20 years of 58% (high-risk MGUS) versus 37% with any 2 of these risk factors (high-intermediate risk), 21% with one risk factor (low-intermediate risk), and 5% when none of the risk factors were present (low risk).

Aged↗
PubMed2005

Diagnostic performance of quantitative kappa and lambda free light chain assays in clinical practice.

BACKGROUND: The quantitative assay for free light chains (FLCs) is a recently introduced commercial test reported to be sensitive and specific for detecting FLC diseases such as primary systemic amyloidosis (AL), light chain deposition disease (LCDD), nonsecretory multiple myeloma (NSMM), and light chain multiple myeloma. We evaluated its diagnostic performance in clinical practice. METHODS: All FLC clinical test results generated in 2003 were abstracted from the Laboratory Information System. Diagnoses were obtained from the Dysproteinemia database and the patient medical history. RESULTS: In 2003, we received samples for FLC assays from 1020 Mayo Clinic patients. The majority of these patients (88%) had bone marrow-derived monoclonal plasma cell disorders (PCDs). The 121 patients who did not have monoclonal gammopathy all had FLC kappa/lambda ratios within the range of values obtained for a reference population in our laboratory. Among the patients with monoclonal gammopathies were patients with multiple myeloma (330), AL (269), monoclonal gammopathy of undetermined significance (114), smoldering multiple myeloma (72), plasmacytoma (22), NSMM (20), macroglobulinemia (9), LCDD (7), and a variety of other PCDs. Among the 110 AL patients who had not been previously treated and who had a FLC assay performed within 120 days of diagnosis, the FLC kappa/lambda ratio was positive in 91% compared with 69% for serum immunofixation electrophoresis (IFE) and 83% for urine IFE. The combination of serum IFE and serum FLC assay detected an abnormal result in 99% (109 of 110) of patients with AL. CONCLUSION: The performance of the FLC assay in this analysis of clinical laboratory data is consistent with results from published retrospective validation studies.

Amyloidosis↗
PubMed2005

Endometrial cancer: can nodal status be predicted with curettage?

OBJECTIVE: To determine whether histologic or molecular markers assessed in pretreatment curettage specimens predict nodal metastasis in endometrial cancer. METHODS: Phenotypic and molecular variables (ploidy, proliferating cell nuclear antigen, MIB-1, p53, HER-2/neu, and bcl-2) were analyzed in preoperative specimens from 82 patients with endometrial cancer who had lymph nodes dissected. These 82 patients had been selected from a total population of 283 patients with endometrial cancer, using a case-cohort design. Weighted logistic regressions were then used to determine significant predictors of positive lymph nodes, and results were estimated for the total population of 283 patients. RESULTS: Of the overall population, 12% of patients were estimated to have positive lymph nodes. Histologic subtype, p53, and bcl-2 each were significantly correlated (P <0.05) with lymph node status. With application of stepwise logistic regression, p53 was the only independent predictor of lymph node status. In addition, a statistical model predictive of positive lymph nodes was generated which incorporated the risk factors p53, bcl-2, and histologic subtype. CONCLUSION: In pretreatment curettage specimens, the presence of unfavorable levels of p53 or bcl-2 or of nonendometrioid histologic features, or combinations of those, significantly predicted lymph node status, thus facilitating the preoperative identification of patients at risk of lymph node metastases.

Adult↗
PubMed2004

Presence of monoclonal free light chains in the serum predicts risk of progression in monoclonal gammopathy of undetermined significance.

We hypothesized that the presence of monoclonal free light chains (FLC) in the serum of patients with monoclonal gammopathy of undetermined significance (MGUS) is a marker of clonal evolution and a risk factor for progression. Forty-seven patients with MGUS and documented progression to myeloma or related malignancy were compared with 50 age- and gender-matched patients with MGUS and no evidence of progression after 5 or more years of follow-up. The presence of an abnormal kappa/lambda FLC ratio in the serum was associated with a higher risk of MGUS progression (relative risk 2.5; 95% confidence interval: 1.6-4.0; P < 0.001).

Biomarkers, Tumor↗
PubMed2004

Flow cytometric assessment of TCR-Vbeta expression in the evaluation of peripheral blood involvement by T-cell lymphoproliferative disorders: a comparison with conventional T-cell immunophenotyping and molecular genetic techniques.

Molecular genetic T-cell receptor (TCR) and flow cytometric analysis using antibodies to conventional T-cell antigens and TCR beta-chain variable region families (TCR-Vbeta) were performed in 65 peripheral blood specimens evaluated for potential involvement by a T-cell lymphoproliferative disorder (TCLPD). A normal or reactive conventional T-cell immunophenotype was present in 36 cases; TCR-Vbeta flow cytometric and molecular TCR analyses were negative for clonality in 32 and 27 of these cases, respectively. In the remaining normal and reactive cases, one or both methods seemed to detect dominant cell populations in settings with limited T-cell diversity. We identified 29 TCLPDs; all studied cases had clonal molecular TCR results; 23 TCLPDs had clonal TCR-Vbeta flow cytometric results; the remaining were suggestive of (n = 3) or negative (n = 3) for clonality. TCR-Vbeta flow cytometric analysis is a powerful clinical laboratory tool that can be used to aid in the rapid diagnosis of peripheral blood involvement by T-cell malignant neoplasms.

Antigens, Differentiation, T-Lymphocyte↗
PubMed2003

Molecular and histopathologic predictors of distant failure in endometrial cancer.

A case-cohort study was designed to correlate various histopathologic and molecular variables with distant failure in endometrial cancer by analyzing phenotypic and molecular indices in hysterectomy specimens. From an overall population of 283 patients with endometrial cancer, we selected a cohort including all 49 patients who experienced any recurrence and 76 randomly chosen patients without recurrence. Expression of nuclear proliferating cell nuclear antigen (PCNA), MIB-1 (a marker of cell proliferation), and p53 was determined with digital image analysis, and cell membrane HER-2/neu and bcl-2 were quantitated visually. Ploidy and DNA indices were determined with flow cytometry. Overall, 6 immunohistochemical and 11 flow cytometric cases were eliminated because of technical inadequacies. Distant failures were defined as primary recurrences that developed outside the pelvis or vagina. Median follow-up was 91 months. Distant failures occurred in 13% of the patients. Cervical stromal invasion, positive adnexae, myometrial invasion >50%, positive lymph nodes, positive peritoneal cytology, lymphovascular invasion, grade 3 histology, nonendometrioid subtype, p53 >33%, strong HER-2/neu membranous staining, aneuploidy, S-phase fraction > or =9%, proliferative index > or =14%, and DNA index > or =1.5 significantly (P<0.05) predicted distant failures. However, a logistic regression model identified only p53 (OR=43.73; P<0.005), lymphovascular invasion (OR=11.59; P<0.001), and cervical stromal invasion (OR=11.29; P=0.001) as cogent predictors of distant failures. Only 3% of patients without any of these three predictors developed distant failures compared with 36% of those with at least one of the three (P<0.01). Thus, locoregional therapy may be insufficient when at least one of these predictors is present.

Adult↗
PubMed2003

Prognostic impact of acute myeloid leukemia classification. Importance of detection of recurring cytogenetic abnormalities and multilineage dysplasia on survival.

To evaluate the prognostic impact of acute myeloid leukemia (AML) classifications, specimens from 300 patients with 20% or more bone marrow myeloblast cells were studied. Specimens were classified according to the French-American-British Cooperative Group (FAB), the World Health Organization (WHO), the Realistic Pathologic Classification, and a cytogenetic risk group scheme. Cases with fewer than 30% blast cells did not have a 5-year survival significantly different from cases with 30% or more blast cells, and survival was similar for the low blast cell count group and cases with multilineage dysplasia and 30% or more blasts. Categories of AML with recurrent cytogenetic abnormalities of t(15;17), t(8;21), inv(16)/t(16;16), and 11q23 showed significant differences in 5-year survival. No significant difference was identified between AMLs arising from myelodysplasia and de novo AMLs with multilineage dysplasia, but all cases with multilineage dysplasia had a worse survival than all other AMLs and other AMLs without favorable cytogenetics. FAB types M0, M3, and M4Eo showed differences in survival compared with all other FAB types, with M0 showing a significant association with high-risk cytogenetics and 11q23 abnormalities. Other FAB groups and WHO AML, not otherwise categorized subgroups did not show survival differences. These findings suggest that the detection of recurring cytogenetic abnormalities and multilineage dysplasia are the most significant features of current AML classification.

Acute Disease↗
PubMed2003

Quantitative analysis of serum free light chains. A new marker for the diagnostic evaluation of primary systemic amyloidosis.

Primary systemic amyloidosis is a plasma cell dyscrasia characterized by the accumulation of excess free immunoglobulin light chains (FLCs) as amyloid. One of the diagnostic features of amyloidosis is the presence of circulating monoclonal FLCs in the serum and urine of the patients. The FLC usually is present in small amounts, and immunofixation is required for detection. A nephelometric method for quantitating FLCs in serum has been described using antibodies that recognize only FLC not bound to heavy chain. We describe a retrospective study using this quantitative FLC method for assessing monoclonal FLCs in 95 patients with amyloidosis. The sensitivity of nephelometric serum FLC measurements is particularly useful in patients with negative immunofixation results for serum, urine, or both. In addition, the FLC assay can be used for follow-up of patients with amyloidosis who have undergone stem cell transplantation.

Amyloid↗