When the physician leaves the patient: predictors of satisfaction with the transfer of care in a primary care clinic

OBJECTIVE

To identify independent predictors of patients' satisfaction with transfer of their care from a departing to a new resident physician.

DESIGN

A self-administered questionnaire completed by consecutive patients following up after transfer of their care, and by a randomly selected 50% of patients not returning within three months after transfer.

SETTING

An internal medicine clinic in a teaching hospital.

PATIENTS

Questionnaires were completed by 376 patients: 237 returning to clinic and 139 (91%) of 152 randomly selected patients who had not returned. Mean age of the patients was 65 years, 52% were men, and they had come to the clinic for a median of four years.

RESULTS

57% of the patients were satisfied with the transfer process, 25% were neutral, and 18% expressed frank dissatisfaction. Of nine variables significantly associated with satisfaction by univariate analysis, stepwise multiple regression identified five independent predictors. Personal notification of the patient by the departing physician was the most powerful determinant, explaining 41% of the variability in satisfaction. Other predictors were whether patients believed their physicians had done everything possible to facilitate transfer, whether the departing physician had provided opportunity for discussion of the transfer, whether this discussion was considered sufficient, and patients' impressions of the institution.

CONCLUSIONS

Most of the predictors identified can be influenced by physician behavior, suggesting that physicians should personally notify patients of their departure and provide an opportunity for discussion. This could significantly improve patient satisfaction with the transfer process and, as previous studies suggest, translate into greater compliance with medications and follow-up.

The German health care system: model or mirage?

Rising costs have spurred America's leaders to look abroad for a model upon which to pattern reform of our health care system. On the surface, at least, Germany would appear to have an ideal system combining universal access, high quality, free choice of physicians, and cost control. Germany has been particularly effective in curbing pharmaceutical and administrative expenses, and has avoided the progressive imbalance between primary care providers and medical specialists seen in America. However, Germany lags behind the US in emphasizing preventive services and in shifting services to the ambulatory setting. Also, an oversupply of physicians, lack of incentives to limit the volume of services, and a global budget cap have combined to induce physicians to do more while their incomes were falling sharply relative to those of other workers. Although selected elements of the German health care system could be beneficial to America, full-scale adoption of the German system is neither realistic nor desirable.

Absence of true seroreversion of HIV-1 antibody in seroreactive individuals

OBJECTIVES

First, to determine whether there is evidence for loss of human immunodeficiency virus type 1 (HIV-1) antibody in seroreactive individuals. Second, if true seroreversion occurs, to determine its incidence relative to errors in the testing process.

DESIGN

A retrospective cohort study reviewing the results of 5,446,161 HIV-1 antibody tests performed on 2,580,974 individuals (the US Army HIV Data System) from 1985 through 1992. For all patients with one or more seroreactive sample followed by one or more nonreactive sample, we examined available records and retested the samples.

PARTICIPANTS

Serum samples had been obtained from active-duty and retired military personnel, their dependents, and applicants to the military.

RESULTS

Of 4911 individuals reported to be seroreactive for HIV-1 by two independent samples, only six were potential seroreverters. Review of the six cases revealed that five actually were HIV-seroreactive patients who had samples from nonreactive individuals mistakenly attributed to them, while the sixth had a testing error proven by retesting the discrepant specimen. Errors in the testing process were identified (n = 23) or suspected (n = 3) in another 26 individuals who had not had independent confirmation of reactivity by a second sample. The cumulative error rate was 12.4 per 1 million patients tested. An additional group of 31 uninfected infants appeared to serorevert due to loss of antibody acquired from their HIV-1-infected mothers.

CONCLUSIONS

Review of this database demonstrates no evidence for true seroreversion of HIV-1 antibody status. We conclude that if seroreversion occurs at all, it is exceedingly rare. In fact, most (if not all) cases of apparent seroreversion represent errors of attribution or testing.

Endopeptidase inhibition and intestinal antigen processing in mice

The role of gastrointestinal digestive processes in the systemic availability of ingested protein antigens was examined by feeding the trypsin inhibitor aprotinin intragastrically to mice and measuring uptake of ovalbumin and 14C-polyethylene glycol (MW 4000) from the gastrointestinal tract. Trypsin and chymotrypsin activities in the intestinal lumen were significantly reduced by aprotinin feeding. Aprotinin slowed stomach emptying, but radioimmunoassays for immunoreactive ovalbumin in the serum of mice prefed aprotinin showed 12-fold elevations within 1 hr after ovalbumin feeding. Uptake of a nonmetabolized macromolecular probe, 14C-polyethylene glycol-4000, increased less than two-fold when fed with aprotinin under the same conditions, indicating that the increased uptake of immunoreactive ovalbumin was not due to changes in intestinal permeability. The results show that inhibition of luminal proteolysis caused significant increases in the serum concentration of immunoreactive ovalbumin, indicating that acute inhibition of luminal proteases permits larger quantities of relatively intact protein to interact with mucosal absorptive surfaces. These results support the hypothesis that pancreatic proteases modulate antigen absorption from the lumen in adult animals.

Inhibition of orally-induced immune tolerance in mice by prefeeding an endopeptidase inhibitor

Intragastric feeding of T-dependent protein antigens to mice induces substantial systemic tolerance in specific antibody and cell-mediated immune responses. To evaluate the role of gastrointestinal digestion in this phenomenon, the trypsin inhibitor aprotinin was fed to adult BDF1 mice prior to tolerogenic feedings of ovalbumin or human gamma globulin. As assessed by measurement of protein-specific antibody responses, aprotinin significantly reduced tolerance induced by feeding carrier protein, but not tolerance induced by parenteral antigen injection. Aprotinin also reduced oral tolerance to ovalbumin as measured by delayed-type hypersensitivity and T cell proliferative responses. However, aprotinin did not alter antibody tolerance to a carrier-associated hapten in the same animals. Feeding of human gamma globulin concomitantly with aprotinin induced specific antibody responses without further immunization, and reduced subsequent tolerance. Aprotinin also increased the level of immunologically detectable ovalbumin found in the serum following antigen feeding. The data support the hypothesis that aprotinin indirectly mediated changes in specific stimuli available to the lymphoid system as a result of alterations in gastrointestinal processing of fed antigens rather than to direct effects of aprotinin upon systemic immune responses.

Efficacy of bovine milk immunoglobulin concentrate in preventing illness after Shigella flexneri challenge

The protective efficacy of oral bovine immunoglobulin concentrates derived from colostrum against challenge with Shigella flexneri was studied in healthy adult volunteers in a randomized, double-blind fashion. Volunteers were given a product consisting of hyperimmune immunoglobulin concentrate with a high titer of anti-S. flexneri 2a lipopolysaccharide (LPS) with sodium bicarbonate or a control preparation with sodium bicarbonate three times a day for seven days. On the third day of treatment, volunteers received a challenge of 10(3) colony-forming units of S. flexneri 2a strain 2457T. None of the volunteers who received the high-titered hyperimmune product became ill, compared with 45% of volunteers who received the placebo (P less than 0.05). The duration of shedding of the challenge organism was decreased, and the active immune responses to S. flexneri LPS were less frequent and of lower magnitude in volunteers given the immunoglobulin concentrate than in those in the control group. High-titered, orally administered bovine immunoglobulin concentrate protects against shigellosis and may be useful in preventing shigellosis among travelers, military personnel, and individuals at risk during a Shigella outbreak.

Histopathologic and immunohistochemical changes in gut-associated lymphoid tissues after treatment of rabbits with dexamethasone

Corticosteroids cause impaired cell-mediated immunity which may encourage development of gastrointestinal and respiratory infections. In order to better understand the effects of corticosteroids on gastrointestinal immunity, immunological and histological changes in gut-associated lymphoid tissues were examined after intravenous administration of dexamethasone to rabbits. In treated animals, lymphoid domes and follicles were considerably reduced in size, and the dome epithelial layer was markedly depleted of M cells and lymphocytes. There were numerous open lesions at the luminal surface of dome epithelium, consistent with necrosis of M cells, and a striking depletion of follicular B cells in treated animals. These immunologic and histologic effects of corticosteroids could have found profound, deleterious effects on mucosal immune responses and host resistance to microbial infections.

A novel surface antigen expressed by mature and activated rabbit T-lymphocytes

The monoclonal antibody (Mab) 93C6 was used to identify a surface molecule expressed by mature and activated rabbit T-lymphocytes. This antigen was virtually absent in cells of the thymus (5% positive cells). All 93C6-positive cells expressed the rabbit pan-T marker L11-135 and proliferated in response to concanavalin A (Con A). When lymphocytes were activated in the presence of Con A, the expression of the 93C6 molecule was quantitatively increased. Con A stimulation alone did not markedly enhance expression of this antigen by thymocytes, but stimulation with both Con A and interleukin-2 (IL-2) resulted in a population of thymocytes that expressed the antigen in a manner quantitatively similar to that of mature T-cells in other tissues.

Precocious development of lectin (Ulex europaeus agglutinin I) receptors in dome epithelium of gut-associated lymphoid tissues

Dome epithelium (DE), the tissue covering lymphoid domes of gut-associated lymphoid tissues, was examined in both adult and neonatal rabbit appendix or sacculus rotundus to determine if dome epithelial cells matured earlier than epithelial cells covering adjacent villi. The localization of well-differentiated epithelial cells in rabbit gut-associated lymphoid tissues (GALT) was accomplished histochemically by use of molecular probes: fluorescein isothiocyanate or horseradish peroxidase conjugates of Ulex europaeus agglutinin I (UEA), a lectin specific for terminal L-fucose molecules on certain glycoconjugates. The villus epithelial cells of newborn and 2-, 5-, or 10-day-old rabbits did not bind UEA, but between the twelfth and fifteenth days of postnatal life, UEA receptors were expressed by well-differentiated villus epithelial cells. In contrast to villus epithelium, DE in appendix and sacculus rotundus of neonatal rabbits expressed UEA receptors two days after birth, a feature that distinguished the DE of neonatal GALT for the next two weeks. In adult rabbits, UEA receptors were associated with dome epithelial cells extending from the mouths of glandular crypts to the upper domes; in contrast to the domes, UEA receptors were only present on well-differentiated epithelial cells at the villus tips. Results suggested that in neonatal rabbits most dome epithelial cells developed UEA receptors shortly after birth, reflecting precocious development of DE as compared to villus epithelium. In adult rabbit dome epithelium UEA receptors appeared on dome epithelial cells as they left the glandular crypts, representing accelerated epithelial maturation.

A novel antigen is common to the dome epithelium of gut- and bronchus-associated lymphoid tissues

The dome epithelium (DE) covering bronchus- and gut-associated lymphoid tissues (BALT and GALT) is composed of columnar cells, groups of lymphocytes, M cells, and pre-M cells. Although the cell biology and immunologic processes of this tissue are likely important in the afferent arm of secretory immune responses, virtually nothing is known about biochemical constituents of the DE. Therefore, a monoclonal antibody, 30E5, was used to study the distribution of a novel antigen, common to dome epithelia of GALT and BALT. 30E5 was secreted by a hybridoma, prepared by fusing murine splenocytes, immunized against dome epithelial cells, with P3 X 68/Ag8 myeloma cells. Reactivity of antigens was defined by indirect immunocytochemistry on sections of rabbit tissues or with dissociated epithelial cells. In situ, 30E5-reactive antigen circumscribed each group of dome epithelial lymphocytes, most or all of which were T cells, in rabbit appendix, sacculus rotundus, cecal patch, Peyer's patch, and BALT. In the DE this antigen was associated with the apical surface and the supranuclear or perinuclear regions of epithelial cells, but it was not associated with epithelial cells of villi, epithelium, or with individual lymphocytes. In peripheral lymph nodes, spleen, and in domes and follicles of GALT or BALT, 30E5-reactive antigen was visualized in linear wisps, primarily in regions populated by thymocytes. In other adult tissues, 30E5-reactive antigen was associated with involuntary muscle, myoepithelial cells of lactating mammary gland and with what appeared to be neural dendrites; but it was not found in epithelia other than DE. In neonatal rabbit appendix, this antigen first appeared in the upper dome epithelium two days after birth, a period coinciding with T cell infiltration and M cell maturation. The histologic distribution of 30E5-reactive antigen suggested that it might be a contractile filament, a receptor, or a differentiation antigen. Since 30E5 was associated with DE of both GALT and BALT, results support the concept of a molecule common to all mucosa-associated lymphoid tissues.

Development of dome epithelium in gut-associated lymphoid tissues: association of IgA with M cells

The dome epithelium (DE), which covers gut-associated lymphoid tissues (GALT) and provides both a protective barrier over lymphoid follicles and a route for antigen uptake from the gut, develops in rabbit appendix (caecum) during the first week of neonatal life. To determine if secretory immunoglobulins from maternal milk interact with this developing tissue, their interrelationships in neonatal rabbit appendix were examined by use of immunocytochemical techniques. The glycoprotein, secretory component, was not produced by neonatal rabbits less than 15 days old, since neither the membranous nor the free, secreted forms of maternal secretory component were associated with villi or DE of neonates. Immunoglobulin A (IgA), but neither IgG nor IgM, were noted on DE by light microscopy, even though IgG was abundant in the villus lamina propria and vascular spaces. The epithelial IgA was distributed, in a patchy pattern, across the upper dome surface of some two-day-old, and all five-and ten-day old nursing animals, but IgA was not on DE of rabbits prevented from nursing. Immuno-electron microscopy of appendix from nursed rabbits revealed IgA directly over the apical surface of M cells, where it formed a continuous, thick coating without binding to adjacent immature absorptive cells; it was also within apical vacuoles of M cell cytoplasm. The distribution of IgA on the DE of rabbit appendices indicated that in differentiating GALT, maternal IgA reacted preferentially with M cells or pre-M cells, leading to speculation concerning a role for IgA in the development of GALT and in establishment of mucosal immune responses in neonates.

Diagnosis of spontaneous Clostridium spiroforme iota enterotoxemia in a barrier rabbit breeding colony

Five New Zealand White rabbits (Oryctolagus cuniculus) in a rigid barrier rabbit breeding colony developed acute diarrhea 1 week after weaning. Both Clostridium spiroforme and an iota-toxin were isolated from cecal and colon contents of all five rabbits. When pure isolates of C. spiroforme were administered to two normal healthy rabbits, the rabbits developed identical disease and shed both the organism and the iota-toxin. Results of this study suggested that C. spiroforme is an important enteric pathogen of weanling rabbits and the etiology of this diarrhea complex can be rapidly confirmed using four diagnostic criteria.

Dome epithelial M cells dissociated from rabbit gut-associated lymphoid tissues

Dome and dome epithelial cells were selectively dissociated from gut-associated lymphoid tissues of rabbits. Sequential tissue washes in dithiothreitol, EDTA, and collagenase removed the dome epithelium, without disrupting the follicles or villi, and provided a cell suspension containing 74 +/- 6% lymphocytes, 9 +/- 4% columnar epithelial cells, 10 +/- 7% tangible-body macrophages, and 4 +/- 2% M cells (follicle-associated epithelial cells). The last mentioned cells were characterized by transmission electron microscopy as large (20 to 55 microns diameter) cuboidal, round, or oval cells with eccentric nuclei and thin membranous processes surrounding empty vacuoles. The M cells were occasionally joined together by tight junctions. Histochemical and immunocytochemical analyses of M cells with the light microscope showed that they were devoid of immunoglobulins and negative for T-cell antigen and secretory component and had no detectable alkaline phosphatase or endogenous peroxidase activity. The M cells had few vacuoles with faint acid phosphatase activity; nonspecific neutral esterase was abundant. Possible uses for dome and dome epithelial cells are discussed.