Multiple myeloma and renal failure: one center's experience

Renal involvement remains a major complication of multiple myeloma, particularly in advanced disease. A retrospective analysis was performed of the modes of presentation, treatment and outcome of all patients with multiple myeloma treated in our renal unit between 1987 and 1996. Thirty-four patients were identified: in 26 (76%) the diagnosis of myeloma was made only after referral. Light chains were the most common paraprotein in both serum and urine. Twenty-one (62%) patients underwent renal biopsy: myeloma cast nephropathy was the predominant histological finding in 16 cases. Thirty-one (91%) patients had severe renal failure (GFR < 20 mL/min), with 28 (82%) requiring dialysis within 2 weeks of admission. Despite treatment of presumed precipitaing causes of acute deterioration in renal function, only 1 of these 28 patients subsequently became independent of dialysis. Most had advanced stage myeloma: 29 (85%) were Durie-Salmon stage II or III. Hypercalcemia, sepsis and pathological fractures were the principal complications. Median survival overall was 5 months. The main causes of death were withdrawal of renal replacement therapy (overwhelming myeloma, severe debilitation) and sepsis. Nineteen (56%) patients received long-term (> 1 month) renal replacement therapy with a median survival of 8 months. However, five of these (26%) have survived for more than 12 months on dialysis and report a good quality of life.

Donor antigen is necessary for the prevention of chronic rejection in CTLA4Ig-treated murine cardiac allograft recipients

BACKGROUND

Optimal activation of T cells requires two signals: antigen engagement through the T cell receptor and a costimulatory signal. Previous studies have shown that blockade of the CD28:B7 costimulatory pathway using the soluble fusion protein CTLA4Ig can prevent acute rejection of organ and tissue allografts; however, long-term engraftment has not been seen universally. This study was undertaken to define the role of donor antigen in inducing long-term allograft survival in CTLA4Ig-treated recipients.

METHODS

A murine cardiac allograft model was employed using BALB/c donors and C57BL/6 recipients. Additional donor antigen in the form of donor splenocytes was given at the time of transplantation. Recipients were treated with a single dose of CTLA4Ig 2 days after transplantation.

RESULTS

We find that a single dose of CTLA4Ig prolongs cardiac allograft survival, but permanent engraftment is not observed unless the recipients receive an injection of donor-type splenocytes. Treatment of the donor cells with CTLA4Ig does not by itself prolong allograft survival, which indicates the need for systemic treatment of the recipient. Allografts from animals not receiving donor cells show classic histologic changes of chronic rejection, and most cease function from 1 to 4 months after transplantation. Lethal irradiation of the donor cells does not appreciably affect their ability to prevent late allograft loss.

CONCLUSIONS

Donor cells are required to synergize with CTLA4Ig and prevent late cardiac allograft loss in the murine system. The fact that pretreatment of the donor cells alone is not effective suggests a role for antigen presentation by recipient antigen-presenting cells in the initiation of rejection. As lethal irradiation of the donor cells does not affect their ability to promote long-term engraftment, our data suggest that long-term microchimerism is not required to prevent chronic rejection in this model.

The rapid reversal of profound hypothermia using peritoneal dialysis

Severe hypothermia is associated with serious patient morbidity and mortality. The groups most frequently affected are the elderly, the very young and substance abusers. We describe three such cases which were successfully treated using warmed peritoneal dialysis. Two patients recovered completely and were left with no long term deficits. The third patient recovered from the acute event, but succumbed later to an underlying medical condition. Warmed peritoneal lavage is an efficient, cost effective approach which is easily performed without specialist equipment, and involves minimal risk to the patient.

Evaluation of venous injury caused by a percutaneous mechanical thrombolytic device

PURPOSE

To study venous injury caused by a prototype percutaneous mechanical thrombolytic device.

METHODS

Simulated thrombolysis was performed using the device, or the Fogarty balloon catheter (FBC) as control, in the infrarenal inferior vena cava (IVC) of 40 New Zealand white rabbits. Venous injury was evaluated by cavography, Evans blue dye staining, and histology at 0, 1, and 6 weeks postprocedure.

RESULTS

Both devices resulted in near complete endothelial denudation acutely. No differences in reendothelialization were noted at any time in the proximal and mid-IVC, but there was significantly greater reendothelialization in the distal IVC in the rabbits treated 6 weeks earlier with the device (p < or = 0.04). Additionally, the inner luminal diameter at necropsy for the 1-week rabbits treated with the FBC was significantly narrower in the distal and middle sections of the IVC when compared with the device (p < or = 0.02 for both segments). There was no luminal diameter difference at 0 or 6 weeks.

CONCLUSION

Based on a rabbit model, venous injury from the device was found to be similar to, and in the distal IVC less than, the routinely used FBC.

Serotonin-induced paw edema in the rat: pharmacological profile

1. Serotonin (5-HT) induced a linear increase in paw weight in rats within 1 hr of an intraplantar injection (50 microliters vol) over a concentration range of 0.005-0.2 mg/ml. At the 0.2 mg/ml concentration, a 16-fold increase in paw weight was observed as compared to saline-injected controls. 2. Serotonin antagonists, such as LY53857, were the most effective antagonists of 5-HT induced paw swelling, producing near complete antagonism and an approximate ED50 of 0.1 mg/kg. A mixed 5-HT/histamine antagonist, cyproheptadine, also produced a nearly complete inhibition of the 5-HT response with an approximate ED50 of 1.3 mg/kg. 3. Dopamine agonists (pergolide, quinpirole), yohimbine, dexamethasone and nifedipine also produced a significant degree of antagonism of the 5-HT response. 4. Clonidine, prazocin, chlorpheniramine, cimetidine, various dopamine antagonists, imipramine, cyclosporine A, piroxicam and superoxide dismutase were all ineffective at altering the paw swelling response to 5-HT.

In vivo evaluation of iophendylate-cyanoacrylate mixtures

Cyanoacrylate glue is a rapidly polymerizing agent used for vascular embolization. Polymerization occurs when the glue comes into contact with ions in the blood or on the vascular endothelium. Mixing iophendylate with cyanoacrylate causes slowing of polymerization, allowing flow-directed embolization into the nidus of an arteriovenous malformation (AVM) or the central neovascularity of a tumor or hemangioma. The authors attempted to define the relationship between the iophendylate-glue ratio and polymerization time with an in vivo swine model. In this model, glue setup occurred much more rapidly than predicted on the basis of in vitro studies. This appeared to be due to glue polymerizing on the endothelium at vessel bifurcations and at areas of acute angulation or marked vessel narrowing. On the basis of these data, the authors substantially increased the iophendylate-glue ratio in their most recent AVM embolization procedures and achieved nidus occlusion in each case. With use of the authors' guidelines, it is possible to achieve optimal distal flow-directed embolization with cyanoacrylate.

Bacterial transport within and among various teatcup and cluster assemblies during milking

For evaluation of bacterial transport, two experiments were conducted. In Experiment 1, two nonconventional cluster designs were compared with a conventional assembly. These two units were: 1) conventional unit without a claw and 2) linerless unit without a claw. In Experiment 2, two nonconventional teatcup designs were compared with a conventional teatcup, all attached to a conventional claw. These two were: 1) partial linear teatcup assembly and 2) conventional teatcup with restricted linear wall movement. The three teatcups in Experiment 2 differed only in the lower part of the liner barrel; mouthpiece and short milk tube were identical. A culture of Serratia marcescens bacteria was infused throughout milking into the short milk tube at the right front teatcup assembly. Swabs of liners and teats were used to culture for Serratia marcescens. For Experiment 1, the number of contaminated teats (and liners) was 32 of 144 and 88 of 144 for the conventional cluster, 20 of 144 and 37 of 144 for the clawless cluster, and 10 of 144 and 16 of 144 for the linerless cluster. For Experiment 2, the total number of bacterial transfers was 14 of 25 for the conventional teatcup, 7 of 25 for the restricted liner, and 3 of 25 for the partial liner. These occurrences of transfer correlate well with previously measured reverse pressure gradients across the short milk tube.

A rapid technic for quantitating wound bacterial count

An improved technic has been developed to predict rapidly the critical number of bacteria in tissues. This technic gave reliable and accurate measurements for wounds containing more than 2 X 10(5) organisms per gram of tissue. It is fortuitous that 10(6) bacteria is the critical number of bacteria that will induced clinical infection in experimental animals and humans. The rapid slide technic is now being utilized routinely in our medical center to determine graft bed receptiveness, predict the safety of wound closure, and monitor the course of burns.