Representation of information about family relatives as structured data in electronic health records

BACKGROUND

The ability to manage and leverage family history information in the electronic health record (EHR) is crucial to delivering high-quality clinical care.

OBJECTIVES

We aimed to evaluate existing standards in representing relative information, examine this information documented in EHRs, and develop a natural language processing (NLP) application to extract relative information from free-text clinical documents.

METHODS

We reviewed a random sample of 100 admission notes and 100 discharge summaries of 198 patients, and also reviewed the structured entries for these patients in an EHR system's family history module. We investigated the two standards used by Stage 2 of Meaningful Use (SNOMED CT and HL7 Family History Standard) and identified coverage gaps of each standard in coding relative information. Finally, we evaluated the performance of the MTERMS NLP system in identifying relative information from free-text documents.

RESULTS

The structure and content of SNOMED CT and HL7 for representing relative information are different in several ways. Both terminologies have high coverage to represent local relative concepts built in an ambulatory EHR system, but gaps in key concept coverage were detected; coverage rates for relative information in free-text clinical documents were 95.2% and 98.6%, respectively. Compared to structured entries, richer family history information was only available in free-text documents. Using a comprehensive lexicon that included concepts and terms of relative information from different sources, we expanded the MTERMS NLP system to extract and encode relative information in clinical documents and achieved a corresponding precision of 100% and recall of 97.4%.

CONCLUSIONS

Comprehensive assessment and user guidance are critical to adopting standards into EHR systems in a meaningful way. A significant portion of patients' family history information is only documented in free-text clinical documents and NLP can be used to extract this information.

Decision support for clinical trial eligibility determination in breast cancer

We have developed a system for clinical trial eligibility determination where patients or primary care providers can enter clinical information about a patient and obtain a ranked list of clinical trials for which the patient is likely to be eligible. We used clinical trial eligibility information from the National Cancer Institute's Physician Data Query (PDQ) database. We translated each free-text eligibility criterion into a machine executable statement using a derivation of the Arden Syntax. Clinical trial protocols were then structured as collections of these eligibility criteria using XML. The application compares the entered patient information against each of the eligibility criteria and returns a numerical score. Results are displayed in order of likelihood of match. We have tested our system using all phase II and III clinical trials for treatment of metastatic breast cancer found in the PDQ database. Preliminary results are encouraging.

Antigen receptor rearrangement and expression in acute leukemias

Twenty-two leukemias, 11 of which were undifferentiated with respect to surface antigen markers, were investigated for their antigen receptor gene rearrangement, transcription products of these antigen receptor genes, and surface antigen pattern of the cells. Among the three less-differentiated groups rearrangement was observed in 2/10 cases for the TCR beta-chain and in 4/11 cases for the heavy-chain gene. TCR beta-mRNA, however, was expressed in seven out of eight cases and the mu heavy-chain mRNA in eight out of ten cases investigated. Also mRNA of TCR alpha, the rearrangement of which could not be detected with our probes, was expressed as frequently as TCR beta. Although rearrangement of the appropriate gene was found regularly in the more mature leukemias, transcription of these genes was lower or even lacking. These findings indicate that expression of antigen receptor mRNA in undifferentiated leukemias can be activated by events other than maturational rearrangement.

Quantitative tracing of mRNAs for T- and B-lymphocyte receptor genes in individual cells by in situ hybridization with fluorochrome-labeled gene probes. I. Expression in malignancies carrying B-lineage associated antigens

Acute and chronic lymphatic leukemias were investigated on the single-cell level for the activity of genes coding for the IgM heavy chain and the alpha and beta chains of the T-cell antigen receptor (TCR). We used a new method for preparing highly fluorochrome-labeled gene probes for in situ hybridization, which allowed rapid and quantitative detection of mRNA at the individual cell level. Leukemic cell populations classified as belonging to the B lineage according to their surface antigenic patterns revealed increasing expression of mRNA for the IgM heavy chain (mu mRNA) in a maturation-dependent fashion, which was not correlated to rearrangement of the immunoglobulin mu chain gene--only 66% of the leukemias with rearranged mu gene also transcribed it. TCR mRNA was detected in B-antigen positive leukemic cells. High levels of both TCR and mu mRNA expression in all cells of some of these leukemias allowed the conclusion that these cells simultaneously transcribed the genes for T and B cell antigen receptors. TCR mRNA was also found in what are considered relatively mature B leukemias, lineage cross-over on the mRNA level being observed at a frequency of 23% (five of 22 cases), comparable with that of "inappropriate" receptor gene rearrangement. The quantitation of mRNA with fluorochrome-labeled gene probes in situ may allow determining the degree of gene activation in individual antigenically defined cells and may thus contribute a new tool for characterization of normal and malignant cells.

Antibody-dependent cellular cytotoxicity in multiple sclerosis

The blood serum of patients with multiple sclerosis (MS) was capable of recruiting autologous as well as normal mononuclear leucocytes in specific antibody-dependent cellular cytotoxicity (ADCC) of rat glial tumor CCL 107/C6 cells. The gliotoxic ADCC activity of MS patients was significantly higher than that of normal persons and patients with other neurological diseases. MS serum alone or in combination with guinea pig complement was not cytotoxic for glial targets, and MS leucocytes alone displayed only nonspecific natural killer (NK) cell activity, which did not differ from that of normal persons. MS ADCC activity was tissue-specific for glial cells, being almost negligible for embryonic human lung fibroblasts and nonspecific for HeLa cells. Gliotoxic ADCC activity was higher in more severely disabled MS patients than in those who were less disabled. Patients with chronic progressive MS displayed the most significantly raised ADCC activity against glial cells, while patients in a stationary state had almost normal ADCC activity.

A longitudinal study of immunological parameters in multiple sclerosis: cell-mediated immunity and complement profiles

In a 1 year longitudinal study of twenty-two patients with multiple sclerosis (MS) and twenty-one normal control subjects, peripheral blood leucocytes were stimulated with lipoplysaccharide (LPS), a B cell mitogen, and phytohaemagglutinin (PHA) a T cell mitogen. EA- and EAC-rosette formation was also performed to assay null and B cells respectively, and the serum concentration of the C3 component of complement was determined. For ten multiple sclerosis (MS) patients with stationary phases of the disease, percentages of lymphocytes significantly lower than normal were found with normal leucocyte counts in the peripheral blood. Lymphocyte stimulation by PHA was significantly lower than normal in stable MS, while neither LPS stimulation nor EA- and EAC-rosette formation differed significantly from the controls. The C3 serum concentration was found to be significantly higher than normal. For nine out of twelve MS patients with a fluctuating clinical course, the C3 concentration was elevated during remission, but dropped to normal levels during relapse. None of the other parameters studied could be correlated with the clinical course.

A longitudinal study of immunological parameters in multiple sclerosis. Cytotoxic antibodies

Complement-dependent gliotoxic antibody activity was determined in 22 patients with multiple sclerosis (MS) and 19 normal control persons. Peripheral blood serum was collected from MS patients at about 4-week intervals for one year, and the results of cytotoxicity tests correlated with the course of disease. For 10 MS patients with stable disease, complement-dependent cytotoxic antibodies directed against a noncytocidally infected mouse glial cell line (an as yet unidentified virus) were found in significantly higher than normal titer. For 12 MS patients with fluctuating clinical course, the gliotoxic antibody titer remained relatively constant before relapse. During relapse, the titer remained constant or dropped. With remission initially low titers increased appreciably.

Antibody in the sera of tumor-bearing mice that mediates spleen cell cytotoxicity toward the autologous tumor

Pretreatment of MTV-induced BALB/cfC3H mammary tumor cells with autologous serum results in increased spleen cell cytotoxic activity and the recruitment of previously inactive spleen cells to cytotoxic activity against the target cells. These recruiting antibodies are tumor-specific for individual tumors; pretreatment with such serum of target cells of an MTV-induced mammary tumor obtained from a different BALB/cfC3H female results in blocking of spleen cell activity. The autologous recruiting factors are active at dilutions of 1000 or more of whole serum are found in the 19S fraction after gel filtration.