Evaluation of anti-human leukocyte antigen allo-immunization in pediatric cadaveric kidney transplantation

Forty-eight pediatric cadaveric renal transplantations, performed between May 1986 and February 1997, were retrospectively screened, pre- and post-transplant, for antibodies to human leukocyte antigen (anti-HLA) using complement-dependent cytotoxicity (CDC) assay and enzyme immunoassay (EIA). The correlation between anti-HLA immunization and graft outcome was investigated. The combined analysis of CDC and EIA enabled the differentiation between complement-fixing and non-complement-fixing, anti-HLA class I and anti-HLA class II antibodies. The median post-transplant follow-up for all patients with a functioning graft was 86 months (range 10-138 months). In the whole population, 16 grafts were lost: six following a non-immunologic complication; and 10 as a result of rejection. Of these 10 grafts lost, eight were in patients with pre- and/or post-transplant donor antigen specific (DAS) anti-HLA class I or class I + II antibodies; and two were in patients with DAS anti-HLA class II antibodies only. Three of these grafts were lost in patients with weak pre-existing DAS anti-HLA class I antibodies. Immunological graft loss appeared at a median post-transplant time of 38 months (range 2-68 months). All patients without DAS anti-HLA antibodies had a good graft outcome. The presence of pre- and post-transplant DAS anti-HLA antibodies, especially if directed against HLA class I, were associated with a poor graft outcome. A systematic search for, and identification of, anti-HLA antibodies should therefore be part of a pretransplant evaluation to allow the identification of 'unacceptable' donor HLA antigens, following which the impact of the HLA-cross-match on graft outcome will improve. Screening for DAS anti-HLA antibodies post-transplant could be helpful for detecting patients with an increased risk for graft loss following rejection episodes.

Reading for empathy

As our preoccupation with empathy grows, we cast about for means of inculcating it. Literature has been proposed as an enabling factor for physicians in developing a creative imagination. This essay, using a number of examples, points out that reading for pleasure in areas not necessarily related to medicine, can yield insights into its practice. Thus, sensitizing students and young physicians to the nuances of human interaction described by great writers could constitute part of basic and continuing medical education and might be one way of instilling empathy.

[Quo vadis laparoscopic appendectomy?]

The authors evaluated a group of 282 patients subjected between January 1993 and December 1998 to appendectomy, either by the open or laparoscopic route. They compared the period of work incapacity in the two groups to confirm or rule out the fact that after laparoscopic appendectomy the return to work is faster. The results are more favourable in the group of patients operated by the mini-invasive procedure, but even then the period of work incapacity is twice as long, as compared with other countries.

Sandimmune to Neoral conversion and value of abbreviated AUC monitoring in stable pediatric kidney transplant recipients

Neoral is a new microemulsion formulation of cyclosporin A (CsA) that has been reported to have better absorption characteristics than sandimmune. We converted 25 long-term pediatric renal transplant recipients with a mean age of 14.1 yr and a mean follow-up period of 6.4 yr from sandimmune (SIM) to neoral (NEO) on a 1:1 basis. The mean dosage of SIM or NEO required to maintain 'therapeutic range' steady-state trough levels between 100 and 200 ng/mL was similar. We compared 6-h CsA pharmacokinetic profiles taken approximately 6 months after the conversion to NEO with the previous SIM profiles of the same patients. Generally, in the NEO profiles the time to reach the maximum concentration was shorter and the maximum concentration was higher, showing a rapid decline towards the trough-level when compared to the previous SIM profiles. During intake of NEO the AUC0-12 h in the 12-h profiles correlates strongly with the AUC0-6 h in the 6-h profiles (r = 0.98), a similar finding to that which we reported previously for SIM. The median AUC0-6 h for NEO demonstrates a 70% increase compared to the median AUC0-6 h for SIM. Despite the increased drug exposure NEO was well tolerated and did not cause any apparent toxicity within the first 6 months after conversion. The CsA blood level 2 h after intake of NEO showed a higher correlation with the AUC0-12 h (r = 0.91) than the trough level (r = 0.64). The abbreviated profile based on three early sampling points and calculated by AUCPRED = 335.9 + 1.1*(C1) + 1.1*(C2) + 5.4*(C4) correlated well with the full AUC (r2 = 0.98, p < 0.0001). Mean prediction error (+/- SD) was 0.16% (+/- 4.32), and in no patients did the calculated values fall outside the 10% prediction error limit. We therefore conclude that NEO exhibits a higher bioavailability in children compared to SIM without causing apparent toxicity. Monitoring of the C2 might be a better alternative for trough level monitoring in daily clinical practice. A strategy of three early sampling points (C1, C2 and C4) allows a reliable AUC0-12 h prediction and can reduce the length of observation, making it a useful and cost-effective tool in clinical practice.

[Endoscopic mobilization of the proximal portion of the great saphenous vein]

The authors describe a mini-invasive procedure in surgery of varicosities of the lower extremities. The objective is to reduce surgical trauma and improve the resulting cosmetic effect after extirpation of the great saphenous vein. The method was used in 9 patients of 35 operated between September and December 1998. The initial experience with endoscopic dissection of the proximal portion of the saphenous vein is favourable. The tissue traumatization is smaller, haematoma of the thigh is less common.

Collaborative practice agreements for advanced practice nurses: what you should know

Advanced practice nurses (APNs) seeking employment are often presented with employment practice agreements. A collaborative practice agreement is a written statement that defines the joint practice of a physician and an APN in a collaborative and complementary working relationship. It provides a mechanism for the legal protection of the APN and sets out the rights and responsibilities of each party involved. All APNs, regardless of practice setting, should be knowledgeable about aspects of a collaborative practice agreement before they sign one. The purposes of this article are to delineate basic guidelines for evaluating and developing a collaborative practice agreement and to identify areas of special concern for APNs.

Practice standards: the need for a personal element

With rare exceptions, guidelines for clinical practice lack a personal element that allows for physicians' varying goals and patients' differing preferences. The importance of this element is illustrated by means of four examples: 1, hormone replacement therapy for the menopause; 2, early detection of breast cancer; 3, the treatment of acute streptococcal pharyngitis and 4, the diagnosis of symptoms that do not implicate any specific organ system. The advantages and disadvantages of guidelines are pointed out. Among the advantages are their usefulness as standards for audit and the fact that, in the process of reaching consensus, personal experience is taken into consideration. Chief among the disadvantages is their possible misuse by people outside of the profession. It is concluded that guidelines can be improved if their recommendations consider individual goals and preferences. They can become more influential if attention is paid to their proper dissemination.

Erythropoietin treatment in children with renal failure

Erythropoietin (EPO) treatment dramatically changes the life of a child with end-stage renal disease. The administration of recombinant human (rHu)EPO is beneficial and safe in the predialysis period, during hemodialysis or peritoneal dialysis, and after renal transplantation. The goal of hemoglobin correction should be the level at which normal quality of life is possible without adverse events: in children this is usually 10-11 g/dl. rHuEPO is administered once to twice a week subcutaneously to children before dialysis, during peritoneal dialysis, and after transplantation. There is no real benefit of intraperitoneal administration. In children on hemodialysis two to three times a week IV administration is preferred. Among the many reasons for non-response to rHuEPO, iron deficiency (absolute or functional), infections, and hyperparathyroidism are the most common in the pediatric renal patient. Hypertension is the most-frequent side effect of rHuEPO treatment and needs careful monitoring. Iron should be supplemented orally or IV. No significant beneficial effect of rHuEPO on growth has been demonstrated. However, the association with recombinant human growth hormone therapy is not detrimental in children.

Differences in the recognition by CTL of peptides presented by the HLA-B*4402 and the HLA-B*4403 molecules which differ by a single amino acid

The HLA-B*4402 and B*4403 molecules differ only at residue 156, which borders the peptide binding site. Strong in vivo allogeneic reactions mediated by cytolytic T lymphocytes (CTLs) were reported in patients who received a bone marrow graft mismatched for these B44 subtypes, indicating that HLA-B*4402 and B*4403 molecules present distinct antigens. This could be due either to the presentation of different sets of antigenic peptides or to the recognition by CTLs of conformational epitopes formed by the MHC molecules alone or in association with antigenic peptides. To address this question, we compared the two B44 subtypes in their presentation to tumor-specific CTLs of three peptides, encoded by genes MAGE-3, MUM-1 and Tyrosinase. The peptides bound with similar affinities to B*4402 or B*4403 molecules, as assessed by lytic competition assays. One HLA-B*4402-restricted and one HLA-B*4403-restricted CTL clone were derived against each peptide. When tested for lysis of B*4402 and B*4403 cells incubated with the antigenic peptides, most CTLs showed a marked preference for one of the two B44 subtypes. Using variant peptides incorporating single alanine substitutions, we compared a given CTLs' recognition of its antigenic peptide presented by both B44 subtypes. Some substitutions, which had no effect on the binding of the peptide, affected its recognition by the same CTL differently on B*4402 and B*4403 molecules. These results imply that the conformations adopted by the same peptide on the two HLA-B44 subtypes are different. We conclude that the B44 subtype specificity of T cells results mostly from distinct conformations adopted by the same peptides in the two B44 molecules. This does not exclude the possibility that in some cases the B44 subtype specificity results from the selective binding of a peptide to one subtype. We found several peptides, different from the three mentioned above, that contain the canonical HLA-B44 binding motif and bind to B*4403 but not to B*4402 molecules.

[The changing clinical picture of gastroduodenal ulcer disease]

OBJECTIVE

The authors evaluate the changing clinical picture of gastroduodenal ulceration in recent years.

METHOD

They analysed their own clinical material from January 1994 till April 1998 when at the Second Surgical Clinic in Olomouc 188 patients were hospitalised on account of gastroduodenal ulceration.

RESULTS

The group of patients comprised a high proportion of patients above 60 years of age (102, i.e. 55%) and twice as many cases of duodenal ulcers as compared with gastric ones. In 4% ulcers were present at both sites. In 92% (173 patients) acute admissions were involved and only in 8% (15 patients a planned admission for elective treatment was involved. As to complications haemorrhage was most frequent (84%), perforations in 13% and pylorostenosis in 3%. Of the acute admissions 56 patients were operated, i.e. 32%, the rest were treated by conservative methods. The surgical lethality was 12%, the lethality of the conservatively treated patients 5%.

CONCLUSION

Gastroduodenal ulceration is at present characterised by a predominance of conservative treatment, a decline of elective operations, a high percentage of complications in particular in advanced age, more frequent affection of the duodenum and late indication for surgery, when conservative treatment is not very successful.

Shortcomings of the randomized controlled trial: a view from the boondocks

The randomized controlled trial (RCT), despite its well-known limitations, continues to be regarded as a gold standard in determining whether an intervention does more harm than good. Some recent evidence suggests that it tends to overvalue the modalities it tests. Moreover, the accuracy with which the disorder under consideration is diagnosed can be critical to the performance of a new intervention designed for it. When technological progress allows us to diagnose milder instances, some therapies, possibly useful in dire circumstances, will appear ineffective if most of a trial population is at low risk. Human individuality makes it impossible to duplicate a RCT. As a result, Popper's criterion of falsifiability may not be met and so the carrying out of a large-scale therapeutic experiment may not be a scientific activity. Finally, it is doubtful whether group probabilities derived from RCTs can be safely applied to individuals. These and other reservations concerning the applicability of the RCT to clinical practice are discussed.

[Chronic venous insufficiency--a mini-invasive therapeutic approach]

The authors describe their own experience assembled with treatment of chronic venous insufficiency. During the period from VII/95 to III/98 they operated 257 patients with diseases of the venous system. In 22 patients (8%) they operated 24 times by miniinvasive procedures. Eight times retroperitoneoscopic lumbar sympathectomy and sixteen times endoscopic subfascial dissection of the perforators was performed. The remaining patients (92%) were treated by classical operations of the superficial venous system.

Forecasting the nursing workforce in a dynamic health care market

The ability to discern the interacting factors that affect supply and demand for nurses could help nurse educators and nurse leaders allocate resources to meet these needs. Forecasting models must take into account the interactions of three crucial groups of health care providers--physicians, nurse practitioners, and physician's assistants. Buerhaus has noted that market size, wages, preferences for nursing services, and availability of substitutes influence the demand for nursing services. Changes in nurse supply resulting from Medicare reimbursement for nursing services have not been studied, though it could safely be projected that such reimbursement will increase nurse supply. Nurses with baccalaureate degrees and advanced practice preparation will be in the greatest demand in ambulatory care, managed care, public health, and home care settings, raising concerns again that the educational mix is in need of adjustment upwards.

Mechanisms of inactivation of E-cadherin in breast cancer cell lines

Loss of E-cadherin (CDH1) function is thought to contribute to progression in breast cancer and other solid tumors by increasing proliferation, invasion, and/or metastasis. In some cases, the restoration of CDH1 function may be an important therapeutic option. This possibility will depend on the mechanism by which CDH1 is inactivated. Here we present analyses of CDH1 expression, genetic mutation, and promoter methylation in CDH1 in 10 commonly used breast cancer cell lines. Five cell lines (BT-474, MCF-7, MDA-MB-361, MDA-MB-468, and T-47D) expressed CDH1 and were genetically normal. Five others (SK-BR-3, 600 MPE, MDA-MB-134 IV, CAMA1, and MDA-MB-435) did not express CDH1. Fluorescence in situ hybridization analyses of each of these cell lines showed evidence for the physical deletion of one allele of CDH1, and three cell lines were found to carry homozygous deletions. SK-BR-3 was deleted from exon 12 through the promoter; exon 6 was deleted in MDA-MB-134 IV cells, and 600 MPE cells carried a 21-bp deletion in the splicing acceptor site for exon 9. CAMA1 seemed to have been inactivated through promoter methylation. No explanation was found for the inactivation of CDH1 in MDA-MB-435.