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Cell-mediated immunity in nutritional deficiency.

Dietary deficiencies of specific nutrients profoundly alter cell-mediated immune responses in man and experimental animals. Both moderate and severe deficiencies are associated with significant changes in immunocompetence. Diets with inadequate levels of protein, calories, vitamin A, pyridoxine, biotin and zinc result in loss of thymic cellularity. Secondary to thymic atrophy, the production of thymic hormones critical for the differentiation of T lymphocytes is reduced, especially in protein-calorie malnutrition and zinc deficiency. Confirmation of a T cell maturational defect in nutritional deprivation comes from the observations of decreased total (T3 and rosette-forming) T cells in the peripheral blood of children with kwashiorkor and marasmus, with preferential loss of helper/inducer (T4) T cell subsets. Reduced number and in vitro function of T cells have also been reported in experimental deficiencies of iron, zinc, copper, and vitamins A and E. Loss of cutaneous hypersensitivity to mitogens and antigens is a consistent sequela of dietary deficiencies of protein, vitamins A and C, pyridoxine, iron and zinc. Cell-mediated immunity directed against allogeneic histocompatibility antigens (e.g. mixed leukocyte cultures, graft versus host, skin graft rejection) may actually be enhanced by experimental protein and polyunsaturated fat deficiencies. Alternatively, pyridoxine, ascorbate and biotin deficiencies resulted in delayed rejection of skin allografts. Cytotoxic T lymphocyte (CTL) activity is impaired in zinc-, iron- and copper-deficient mice, as well as in scorbutic guinea pigs. Natural killer (NK) cell function may be either enhanced or depressed, depending upon the nutrient and its effects on interferon production. Several authors have demonstrated normal or enhanced macrophage activity in a variety of experimental deficiencies. The extrapolation of these observations to infectious disease resistance is not straightforward, and depends upon the nature of the microbe, its own nutrient needs, and the relative importance of innate, as opposed to immunologic, defense mechanisms.

Animals↗

[Surgical treatment of fractures of the clavicle--Indication, surgical technique and results].

UNLABELLED: 46 cases of clavicular fracture (25 of the middle third and 21 of the distal third) are reviewed concerning indications for surgery, surgical technique and postoperative results. In 32 cases surgery was necessary due to dislocation (in 7 cases with a rupture of the coracoclavicular ligaments), 3 times due to a complex trauma of the shoulder joint, 3 times due to a local neurovascular involvement, 3 times due to a delayed fracture healing and 3 times due to a pathological fracture. In two cases an open fracture required osteosynthesis. The most frequent surgical procedure was plate osteosynthesis using the following materials: 3.5 mm LCDC plate, the so called "Balser plate" and the "Ulrich plate", 3.5 mm reconstruction plate, 3.5 mm T-plate and compound plate. In 14 cases autogenous bone grafting was performed. Additional suture of the coracoclavicular ligaments was indicated in 7 patients. In every case early physiotherapy followed the surgical procedure. COMPLICATIONS: in 2 cases an avascular pseudarthrosis emerged after plate osteosynthesis without autogenous bone grafting. In one case a non-union developed due to infection. Moreover we found a loosening of a "Balser plate" and in one patient the development of keloid tissue. The functional outcome according to the Constant score was good. 32 patients achieved 89 out of 100 possible points (average follow up 31 months). In distal clavicle fractures we prefer the use of the "Balser plate" combined with a suture of the coracoclavicular ligaments. Due to the occurrance of delayed fracture healing with pseudarthrosis (2/25) in fractures of the middle third, the indication for surgical treatment has to be discussed. In case of local soft tissue trauma and damage of the periostal blood supply, plate osteosynthesis in combination with autogenous bone grafting should be performed.

Adolescent↗

Problems in the long-term renal allograft recipient.

Despite great improvement in patient and graft survival, the long-term morbidity and mortality in renal transplant recipients are still significant. Cardiovascular disease accounts for much of the mortality in long-term survivors; screening before the transplant procedure and adequate control of hypertension should help improve patient survival. Many of the gastrointestinal complications are due to overimmunosuppression and sepsis. Adequate management must include withdrawal of all immunosuppressive medications in order to save the patient's life. Liver disease is usually of viral origin; patients with chronic active hepatitis or cirrhosis should remain on dialysis. Chronic rejection is the major cause of graft loss in long-term survivors; it is unresponsive to antirejection treatment and its progression may be mediated by nonimmunologic mechanisms. Correctable problems such as renal artery stenosis and ureteral obstruction should be ruled out before a late deterioration in graft function is disregarded as chronic rejection. Post-transplant diabetes, osteonecrosis, cataracts, and nephrotoxicity are directly related to the various immunosuppressive drugs currently used. The lowest dose compatible with graft acceptance should help reduce the incidence of these nonfatal but significant complications. Recurrence of disease is a common histologic finding in many transplant recipients but, except for a few diseases such as HUS, FSGS, and oxalosis, it usually does not lead to graft failure. Successful transplantation restores fertility in many uremic patients. Adequate counseling on contraception is imperative in order to avoid unwanted pregnancies and to delay parenthood for at least 1 year. Current immunosuppressive agents are not teratogenic, no dose adjustments are necessary, and an ill-advised decrease in medication may precipitate a rejection episode. Premature delivery is the major problem in these patients and can be avoided by maintaining adequate graft function and controlling hypertension and infections. It is evident from this review that most of the long-term morbidity and mortality seen in renal allograft recipients are due to overimmunosuppression with sepsis or to side effects of the individual drugs, steroids being a common denominator in almost all cases. New immunosuppressive protocols must aim not only to improve patient and graft survival but also to avoid the many complications that limit the full rehabilitation of these patients.

Graft Survival↗

Acute corneal hydrops in keratoconus.

PURPOSE: To determine the clinical factors associated with the development of acute corneal hydrops and its subsequent outcome. METHODS: The authors identified 147 eyes (124 patients) with acute hydrops from a database of 5242 eyes (2723 patients) with keratoconus. They compared the clinical features of patients in whom hydrops developed with unaffected patients and assessed the progression to penetrating keratoplasty by actuarial methods. RESULTS: Patients in whom acute hydrops developed tended to be younger males who had advanced corneal ectasia and a poor corrected Snellen visual acuity at the diagnosis of their keratoconus (P < 0.001). Acute hydrops also was more common in the presence of severe allergic eye disease (P < 0.001). The development of hydrops was a very significant risk factor for subsequently receiving a penetrating keratoplasty (P < 0.00001) and at the end of the study period 87 (59%) of the 147 eyes had surgery for visual rehabilitation. These eyes had a greater rate of graft rejection than eyes grafted without hydrops (P = 0.02). After resolution of the hydrops, 46 of the 60 unoperated eyes had been refitted with contact lenses, of which 28 (61%) achieved a Snellen visual acuity of 20/40 or better, although a better visual acuity often was present in the contralateral eye. Microbial keratitis developed in two of these eyes after refitting. CONCLUSIONS: Although a penetrating keratoplasty often is indicated for visual rehabilitation after acute corneal hydrops, there is an increased rate of rejection. Only a minority of eyes were re-established in contact lenses after resolution of hydrops, but some patients achieved a functional level of visual acuity such that the procedure could be delayed or avoided.

Acute Disease↗

Marchetti nailing of humeral shaft delayed unions.

The purpose of this study is to present the results of Marchetti nailing in humeral shaft delayed unions. Fifteen humeral shaft delayed unions were treated with the Marchetti nail. The average age of patients was 52.3 years. All had been treated initially by conservative methods. Delay from trauma to surgery averaged 4.8 months. The nailing technique was retrograde, and reaming of the fracture focus was always performed. Bone graft was not added. Thirteen patients achieved union, in an average of 3.3 months. Two patients require further surgery to gain union. Shoulder and elbow motion was excellent in 10 patients, moderate in four and poor in one. The functional result was excellent in nine patients, good in two, fair in two, and poor in two. Marchetti nailing seems to be an acceptable alternative for humeral shaft delayed unions.

Adult↗

Analyses of the UNOS Scientific Renal Transplant Registry at three years--early events affecting transplant success.

The success of cadaveric renal transplants in the first year is determined largely by events that transpire during the transplant hospitalization. This conclusion is based upon analyses of data on 19,525 cadaver donor renal transplants performed since October 1987 and reported to the UNOS Scientific Renal Transplant Registry from more than 200 centers nationwide. Graft survival rates at 1 year differed by 20-30% depending upon whether or not the transplanted kidney functioned immediately and upon whether the patient required dialysis during the first week posttransplant, experienced rejection, or was discharged with a kidney that was functioning well. Recipients whose discharge serum creatinine level was less than 2.6 mg/dl or whose graft was functioning well at the time of discharge had 88% 1-year graft survival. A multistep logistic regression analysis showed cold ischemia time, transfusions, donor age and cause of death, HLA-DR mismatches, and peak sensitization to be significant factors in the first week. Prophylactic antilymphocyte antibodies (ALG/OKT3) reduced the incidence of rejection from 30% to 20% during the transplant hospitalization, but apparently only delayed rejection. By 6 months there was only a 3% reduction with ALG and a 5% reduction with OKT3 in the incidence of reported rejection and a 2% difference in 1-year graft survival. Although graft and patient survival are important measures of transplant success, graft survival is predicted upon both early and late events. The course of the transplant during the initial hospitalization and the quality of function at discharge were the strongest determinants of 1-year graft survival.

Adolescent↗

Revascularization of a seven-week-old infant lower extremity: case report.

A seven-week-old infant suffered a closed segmental fracture of the left tibia and fibula complicated by vascular disruption and a secondary compartment syndrome. Initial orthopedic assessment revealed a clinically mottled, cool, pulseless extremity 4 hr post-injury. Radiologic investigations showed multiple displaced fractures of both the tibia and fibula. The infant underwent four compartment fasciotomies and intramedullary nailing of the tibial fractures. The vascularity of the limb failed to improve significantly. Angiograms done 22 hr post-injury revealed disruption of arterial inflow just distal to the bifurcation of the tibial peroneal trunk and posterior tibial artery. Urgent revascularization utilizing a contralateral greater saphenous vein graft was undertaken with a successful outcome. Despite delay in transport from the community hospital and lack of definitive management of the vascular injury, the infant has had a good-to-excellent functional outcome.

Compartment Syndromes↗

Primary post-traumatic mandibular reconstruction in infancy: a 10-year follow-up.

Ballistic trauma to the craniofacial skeleton combines the challenges of complex bone injury and loss with severe soft tissue injury and violation of the naso-orbital or oropharyngeal cavities. The authors report a patient who experienced a unique ballistic injury at 28 months of age that resulted in loss of the mandibular ramus and condyle. A segmental injury to the facial nerve was also identified. Primary costochondral grafting and delayed interpositional nerve grafting was undertaken. After 10 years, the patient has nearly 40 mm of opening, with only slight deviation to the injured side. Her facial nerve regeneration provides complete orbicularis oculi function, oral competence, and only slight facial asymmetry. This traumatic reconstruction differs from that of patients with hemifacial microsomia or post-traumatic/arthritic ankylosis in that the joint space itself was spared. Thus, the costochondral graft benefits from the remaining articular disk and upper disk space and is able to rotate and translate. Function and growth are adequately re-established, even in this young pediatric patient.

Bone Plates↗

T cell immunity induced by allogeneic microglia in relation to neuronal retina transplantation.

Microglia share a lineage relationship with bone marrow-derived monocytes/macrophages and dendritic cells, and their inclusion in retinal and brain transplants may function as "passenger leukocytes. " In other solid allografts, passenger leukocytes are the primary sources of immunogenicity, triggering alloimmune rejection. We have conducted a series of in vitro and in vivo studies examining the capacity of microglia cultured from forebrain to activate alloreactive T cells and to induce and elicit alloimmunity. Cultured microglia expressed class II MHC molecules and costimulatory molecules (B7-1, B7-2, and CD40), and they secreted IL-12. Cultured microglia injected s.c. into naive recipients induced allospecific delayed hypersensitivity and elicited delayed hypersensitivity directed at alloantigens. Cultured microglia differed from conventional APCs by secreting significant amounts of mature TGF-beta2, but smaller amounts of IL-12. Moreover, while both cultured microglia and conventional APC stimulated T cell proliferation in vitro, microglia directed the responding T cells toward the Th2 pathway in which IL-4, but not IL-2 and IFN-gamma, was secreted. The abilities of microglia to secrete TGF-beta2, to stimulate alloreactive Th2 cells, and to induce anterior chamber associated immune deviation when injected into the eye of naive allogeneic mice suggest that they are not typical passenger leukocytes. The unique functional properties of cultured microglia may account for the capacity of neonatal retinal tissue transplanted into the eye to alter the systemic alloimmune response in a manner that delays, but does not prevent, graft rejection.

Animals↗

Prolongation of discordant renal xenograft survival by depletion of complement. Comparative effects of systemically administered cobra venom factor and soluble complement receptor type 1 in a guinea-pig to rat model.

There is an increasing body of evidence to suggest that inhibition of complement activation may be a valuable approach to avert hyperacute rejection. In our study, the guinea-pig to rat discordant kidney xenograft model was adapted for the investigation of renal transplant function and an attempt was made to delay the hyperacute rejection using systemically administered cobra venom factor (CVF) and soluble complement receptor type 1 (sCR1). The saline-treated control recipients experienced a rapid transplant rejection with a xenograft survival averaging 10.5 +/- 2.1 min. Administration of a single 60 U/kg i.v. bolus of CVF significantly prolonged renal graft survival to 20.4 +/- 2.5 h, and by a single bolus of sCR1 (50 mg/kg) a prolongation of graft survival to 18.8 +/- 2.3 h was achieved. The grafts functioned only over periods of 2.5 +/- 0.3 and 2.3 +/- 0.2 h, respectively. No complications of sCR1 were noted. We concluded that complement inhibition by sCR1 may be an important component in the therapeutic approach aiming at the prevention of hyperacute rejection in human organ transplantation.

Animals↗

Mycophenolates in transplantation.

The discovery of mycophenolic acid (MPA) as a potent immunosuppressant, able to inhibit B- and T-cell proliferation by blocking production of guanosine nucleotides required for DNA synthesis, allowed its potential in the field of transplantation to be realized. Mycophenolate mofetil (MMF), an MPA prodrug, has been shown to be an effective immunosuppressant in transplant therapy. Clinical trials in renal, heart, and liver transplant recipients have demonstrated that, in combination with cyclosporine and steroids, MMF therapy can reduce the incidence and severity of acute rejection episodes and improve graft and patient survival as well as graft function. Although MMF is generally well tolerated, optimal therapy may be limited by associated side effects, in particular gastrointestinal (GI) toxicity, which may occur in over 40% of patients. Dose changes resulting from GI side effects may potentially lead to sub-therapeutic dosing and impaired clinical outcomes. An enteric-coated formulation delivering MPA - enteric-coated mycophenolate sodium (EC-MPS) has been developed to improve MPA-related upper GI adverse events. EC-MPS delays the release of MPA, consistent with a functional enteric-coating. Recent clinical trials have demonstrated that EC-MPS is as effective and safe as MMF in both de novo and maintenance renal transplant patients.

Gastrointestinal Tract↗

A preliminary analysis of the balance between Th1 and Th2 cells after CD34+ cell-selected autologous PBSC transplantation.

BACKGROUND: CD34+ cell-selected autologous PBSC transplantation (CD34+ APBSCT) is a procedure used for the treatment of patients with malignant disease that is intended to eliminate residual tumor cells from autologous grafts. However, frequent infectious complications after CD34+ APBSCT can occur. A delay of recovery of the absolute number of CD4+ T cells after transplantation was reported to be one disadvantageous factor. As data on T-cell function after CD34+ APBSCT are scanty, we analyzed changes in T-helper cell 1 (Th1) and T-helper cell 2 (Th2) after CD34+ APBSCT to evaluate immune reconstitution. METHODS: Twelve patients underwent APBSCT (CD34+APBSCT group, n=4, and unselected APBSCT, n=8). Peripheral blood (PB) samples were obtained at 2, 4, 8, 12 and 16 weeks after the transplantation. The dynamics of the Th1 and Th2 were analyzed at a single-cell level, using flow cytometry. RESULTS: In the CD34+ APBSCT group, not only the absolute count of CD4+ T cells but also the proportion of Th1 cells in CD4+ T cells and the ratio of Th1 to Th2 after transplantation were significantly decreased at 2 and 4 weeks after transplantation compared with findings in the unselected APBSCT group. DISCUSSION: We suggest that higher rates of infectious complications after CD34+ APBSCT may be due to the inability of residual T cells from the CD34+ cell selection to generate mature T cells that function adequately against infection. Although further study would be required, our preliminary data provide some information on the immune reconstitution after CD34+ APBSCT and differentiation of T lymphocytes into Th1 and Th2 in vivo.

Adult↗

Does open fasciotomy contribute to morbidity and mortality after acute lower extremity ischemia and revascularization?

A retrospective review was undertaken of 127 lower extremity fasciotomies performed for compartment syndrome after acute ischemia and revascularization in 73 patients with vascular trauma and 49 patients with arterial occlusive disease. One hundred twelve (88%) fasciotomies were performed early (at the time revascularization); 15 (12%) were delayed because of late compartment syndrome diagnosis. Ninety-four (77%) patients had more than one accepted indication for fasciotomy. Double-incision fasciotomy was used in 98 (77%) extremities, single-incision fasciotomy was used in 19 (15%), and fasciotomy-fibulectomy was used in 10 (8%). Fasciotomies were closed in 88 (69%) patients an average of 14 days after surgery. Seven patients needed multiple skin grafting procedures or myocutaneous flaps to close the wound; none compromised limb salvage. Five other patients had minor wound infections that resolved. Functional status returned to preoperative levels by the time of discharge from the hospital in 59 (48%) patients. Thirty-one (24%) patients had residual lower extremity disability related to delayed union of the fracture (five), chronic neuropathy (20), leg swelling (one), or ischemic nonhealing fasciotomy wounds (three); two patients had unrelated disabilities. Fourteen (11%) amputations were required for refractory limb ischemia; two (1.6%) were required for wet gangrene of the foot, which infected the fasciotomy site; the others had open noninfected incisions. Eighteen (15%) patients died of cardiopulmonary failure or multisystem failure or both, without fasciotomy-related problems. Open fasciotomy for compartment syndrome after acute lower extremity ischemia and revascularization was associated with an increased risk of minor wound morbidity. However, limb loss and death resulted from persistent ischemia and underlying systemic disease processes or injuries, but not from open fasciotomy wound complications.

Adolescent↗

Long-term delayed vascularization of human neural transplants to the rat brain.

Human neural transplants are being developed to treat Parkinson's disease. Previous characterization of human transplants focused on neuronal development, while little is known of the interaction between the transplant and its environment, among which blood is of prime importance. We evaluated here the formation of blood vessels in human neural xenografts placed into the brain of rats immunosuppressed with cyclosporin A. Using capillary wall markers, we found that human transplants remain virtually nonvascularized for more than 1 month. Angiogenesis takes place very slowly and the density of blood vessels is still quite poor after 3 months, the fine structure of these capillaries, when they form, is apparently normal. Functional studies indicate that the vascular network formed in the transplant allows blood circulation and exhibits a working barrier to macromolecules. Glucose uptake and consumption and cytochrome oxidase activity are almost undetectable up to 3 months after grafting. These results demonstrate that vascularization is much delayed in human xenografts into the rat brain. This delay is likely to be dependent on the maturation of the transplanted tissue. A dedifferentiation of human endothelial cells cotransplanted with neural cells occurs since histochemical and immunocytochemical markers revealing endothelial cells in the human fetus are not present up to 1 month in the transplant. The origin of this phenomenon is a matter of speculation. How neural cells survive and mature in such conditions are issues of prime interest for the future of human neural grafting.

Animals↗

Pulsatile gonadotropin secretion in pubertal children with chronic renal failure.

We have examined physiological nocturnal secretion of gonadotropins in 6 boys and 2 girls with end-stage renal disease, who had either delayed or disturbed puberty. The 5 patients treated by dialysis had reduced gonadotropin pulsatility for their stage of pubertal maturation, whereas the 3 patients with successful kidney grafts demonstrated a higher nocturnal rise and increased amplitude of gonadotropin pulsatility. It is suggested that the improved gonadotropin pulsatility of transplanted patients is due to their restored renal function.

Adolescent↗

Immune reconstitution following bone marrow transplantation: comparison of recipients of T-cell depleted marrow with recipients of conventional marrow grafts.

The reconstitution of hematopoietic cells and in vitro assays of immunologic function have been followed in leukemic patients after conventional bone marrow transplantation (BMT) (N = 34) and T-cell depleted BMT (N = 52) from human leukocyte antigen (HLA)-identical sibling donors. No effects of the T-cell depletion could be seen on the recovery of myeloid or lymphoid cells as measured by the day to engraftment or by the absolute number of cells through day 100. Normal numbers of lytically active natural killer cells returned the earliest and were rapidly followed in both groups of patients by the appearance of circulating B cells and normalization of the responses to B-cell mitogens. However, the recovery of normal T-cell proliferative responses were more delayed in recipients of T-cell depleted grafts. Significant quantitative differences were seen only during the first 3 months after transplantation. Neither the number of CD3+ T cells nor the ratio of CD4:CD8 positive cells differed markedly between the two transplant groups. Mitogen-induced immunoglobulin production by peripheral blood lymphocytes (PBL) from patients following T-cell depleted BMT was quantitatively less than that of conventional marrow recipients through the first year, with low normal IgM production reached by 4 to 6 months in both groups. IgG production reached low normal 7 to 9 months after conventional BMT but did not remain at this level until 1 year following either type of transplant. Assessment of the incidence of infections from the day the absolute neutrophil count reached 500 until day 180 after transplant revealed no significant differences between the two groups; indeed, the overall nonleukemic mortality was higher in the recipients of conventional bone marrow. Thus, in our series, the removal of mature cells from the marrow graft did not affect the rate or degree of recovery of myeloid and lymphoid cells but did affect the regeneration of in vitro T-cell dependent functions. We noted early quantitative differences and a delay in the normalization of the T-cell functions measured rather than prolonged absolute deficiencies. The in vitro deficiencies did not result in significant clinically apparent differences between the two groups.

Adolescent↗

Human allograft acceptance is associated with immune regulation.

The ultimate goal of transplantation is drug-free allograft acceptance, which is rarely encountered in transplant recipients. Using a novel human-to-mouse "trans vivo" delayed-type hypersensitivity assay, we assessed donor-reactive cell-mediated immune responses in kidney and liver transplant patients, four of whom discontinued all immunosuppression. One of these subjects (J.B.) rejected his graft after 7 years of stable function, while the others (D.S., R.D., M.L.) continue to have excellent graft function 5, 28, and 4 years after the cessation of immunosuppression. PBMCs from J.B. exhibited strong responses to both donor and recall antigens whereas PBMCs from patients D.S., R.D., and M.L. responded strongly to recall, but not donor, antigens. Furthermore, when donor and recall antigens were colocalized, the recall response in these three patients was inhibited. This donor antigen-linked nonresponsiveness was observed in four other patients who are still maintained on immunosuppression. The weakness of donor-reactive DTH responses in these patients is due to donor alloantigen-triggered regulation that relies on either TGF-beta or IL-10. In D.S., regulation is triggered by a single donor HLA Class I antigen, either in membrane-bound or soluble form. This demonstrates that allograft acceptance in humans is associated with an immune regulation pattern, which may be useful in the diagnosis and/or monitoring of transplant patients for allograft acceptance.

Animals↗

Tangential excision of eschar for deep burns of the hand: analysis of 156 patients collected over 10 years.

Deep burns affecting the dorsum of the hand have been treated by tangential excision of the eschar in 156 patients involving 208 hands. From our 10-year experience we have concluded that: If the patient's general condition permits it all hands with deep partial and full thickness skin loss burns are suitable for early tangential excision of the eschar. The best time for the operation is within the first week after injury. If the burn is of limited extent and the requirement for autograft skin is small the operation may be carried out under nerve block anaesthesia. When the burn is more extensive (i.e. involving both hands) intravenous ketamine anaesthesia is recommended. During tangential excision sequential layers of tissue must be removed until the base of the burn appears porcelain white in colour, has a lustrous appearance with many small bleeding points and is firm in consistency. If there are deep burns of the finger webs they are incised or excised and then grafted. Postoperatively an absence of fever, pain or exudation from the wound indicates that inspection of the wound can be delayed for about 2 weeks. By this time the wound is usually healed and functional rehabilitation and physiotherapy can commence.

Acupuncture Therapy↗