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We studied Epstein-Barr (EB) virus excretion and antibody in 41 renal transplant recipients enrolled in a placebo-controlled trial of human leukocyte interferon. Half the patients were also treated with antithymocyte globulin. Epstein-Barr virus excretion occurred more often in recipients of cadaver kidneys (P = 0.03) and those receiving antithymocyte globulin (P = 0.04) and less often in patients given interferon (P = 0.08). Antibody to viral capsid antigen increased fourfold or more in 12 of 22 patients treated with antithymocyte globulin and in none of the non-antithymocyte globulin-treated group (P = 0.0002). Antibody to the restricted component of early antigen rose fourfold or more in eight patients and appeared related to the occurrence of syndromes similar to those attributed to cytomegalovirus in transplant recipients. We conclude that increasing immunosuppression augments the rate of EB virus reactivation and that EB virus may be an important pathogen in heretofore ill-defined syndromes. [ABSTRACT FROM AUTHOR]

Background: Endothelial dysfunction is an early key event in the development of arteriosclerotic cardiovascular disease (ASCVD), thus an early marker of subclinical ASCVD. Endothelial function is impaired in renal transplant recipients (RTR) treated with cyclosporine (CyA). Tacrolimus is associated with less hyperlipidemia and hypertension than CyA, however, there are no data on endothelial function in tacrolimus-treated RTR., Methods: High-resolution brachial ultrasonography was used to assess endothelium-dependent dilatation (EDD), and endothelium-independent dilatation (EID) in 20 stable RTR and a control group of 10 healthy subjects without clinical evidence of ASCVD. The RTR group included patients receiving CyA (n=10) and tacrolimus (n=10). EDD and EID were measured as percent increase in brachial artery diameter in response to reactive hyperemia and nitroglycerin, respectively., Results and Conclusions: EDD was significantly lower in RTR versus controls (1.7+/-0.7 vs. 7.3+/-0.7%, P<0.0001), whereas EID was similar in the two groups. No significant differences were found in EDD or in EID between CyA- and tacrolimus-treated RTR. Glomerular filtration rate, plasma homocysteine, blood pressure, and lipid profiles were similar in CyA- and tacrolimus-treated RTR.

Background: Leukopenia is not infrequently encountered following solid organ transplantation, most often in the setting of cytomegalovirus (CMV) disease and/or its treatment with ganciclovir. The present study was undertaken to determine the safety and efficacy of granulocyte colony-stimulating factor (G-CSF) in renal and liver transplant recipients with leukopenia., Methods: Between 1 June 1991 and 1 June 1998, patients received G-CSF for 2 indications: 1) white blood cell count (WBC) < 3000/mm3, with a decline from baseline; 2) to shorten the duration of leukopenia associated with chemotherapy. A retrospective review of the outcome of such therapy was undertaken., Results: 50 patients were given 100 courses of treatment with G-CSF; 35 of 168 liver transplant recipients (20.8%), 14 of 391 kidney transplant recipients (3.6%), and 1 of 4 recipients of combined liver-kidney transplants (25.0%) received from 1 to 9 courses of G-CSF. Presumed causes of leukopenia were identified as ganciclovir in 28 cases (28.0%), CMV in 21 (21.0%), chemotherapy in 12 (12.0%), sepsis in 11 (11.0%), azathioprine in 5 (5.0%), interferon in 3 (3.0%) and other causes in 20 cases (20.0%). The median length of therapy was 10.0 days (range 1-154 days) and the average dose of daily G-CSF received was 3.9+/-1.5 microg/kg/day. The average WBC was (2.4+/-1.3 )x 10(3)/microl at the beginning of therapy, and (13.8+/-9.1) x 10(3)/microl at the end of therapy. In 7 of 100 treatments (7.0%) a WBC of 5.0 x 10(3)/microl was not reached during G-CSF therapy; in 6 of these 7 cases, G-CSF therapy lasted fewer than 4 days. The mean time needed to reach a WBC count of 5 x 10(3)/microl was 3.7+/-3.3 days among 71 patients who had daily WBC counts sent. Eight G-CSF treatments (8.0%) were followed by episodes of rejection appearing during or within 2 months of treatment; 5 of them were biopsy-documented. No relation was found between the highest WBC obtained during G-CSF therapy and the risk of rejection. Eight patients (16.0%) died while receiving G-CSF, all from infection. Six of these 8 patients were receiving G-CSF for leukopenia secondary to sepsis. Overall, 25 patients (50.0%) received 49 courses of G-CSF secondary to CMV and/or ganciclovir therapy. In 40 of 49 courses (81.6%), ganciclovir could be continued at recommended doses. Twenty-one of 22 patients (95.5%) with symptomatic CMV infection had a clinical response to ganciclovir. Sixteen of 18 patients (88.9%) treated for a CMV infection and followed with serial antigenemia assays attained microbiological cure; both patients who did not were infected with ganciclovir resistant CMV., Conclusion: G-CSF was well tolerated in solid organ transplant recipients. It was particularly useful in patients with CMV disease, allowing optimal ganciclovir therapy.

Background: Although the primary treatment of symptomatic cytomegalovirus (CMV) disease in organ transplant recipients is successful in >90% of individuals, relapsing disease, particularly in those with primary infection, remains an important problem. Previously, we had observed that the rate of symptomatic recurrence was >60% in those with primary disease (seronegative for CMV prior to transplant), and approximately 20% in those who were seropositive prior to transplant. The present study was undertaken to determine whether a maintenance regimen of oral ganciclovir for 2-3 months added to the routine 14-21 days of intravenous ganciclovir would further prevent symptomatic CMV recurrence., Methods: From May 1995 until June 1998, all kidney and liver transplant recipients with confirmed tissue-invasive CMV disease or CMV syndrome were treated with 14-21 days of intravenous ganciclovir (5 mg/kg b.i.d. with dose adjusted for renal dysfunction) followed by 2-3 months of oral ganciclovir (2 g daily). The incidence of recurrence of CMV disease and/or viremia during and after oral therapy was then determined over a mean follow-up of 530.6 days., Results: Thirty-seven patients, 19 kidney and 18 liver transplant recipients, were studied; 5 had biopsy-proven tissue-invasive disease (13.5) and 32 suffered a CMV syndrome (86.5). Twenty-one of these patients (58.6) were seronegative for CMV prior to transplant and received an allograft from a seropositive donor (D+/R-). Overall, 10 patients (27.0) developed CMV recurrence. Eight of 21 patients who were D+/R- for CMV (38.1) developed recurrence as opposed to 2 of 16 patients with other serologic status (12.5) (P=0.14). Patients with recurrent CMV disease and/or viremia had a peak antigenemia assay titer during their initial CMV event of 319.2 positive cells/2 slides compared with 109.8 positive cells/2 slides for patients without recurrent CMV infection (P=0.14); the trend of having a higher peak antigenemia assay titer among patients who recurred occurred both in patients who were at risk of primary CMV infection (D+/R- for CMV) and in those who were not. Two patients developed recurrent infection with strains of CMV that were resistant to ganciclovir., Conclusions: This new therapeutic regimen of oral ganciclovir following intravenous ganciclovir slightly reduced the overall rate of recurrent CMV disease and/or viremia, but it still did not adequately prevent CMV recurrence in patients who are at risk of primary infection prior to transplant. Of particular concern, 2 patients with primary infection treated with this regimen developed ganciclovir-resistant recurrent disease.

Infection remains a significant cause of morbidity and mortality in organ transplant patients, with significant infection being found in more than half of these individuals posttransplant. The most important principles of patient treatment are prevention, early diagnosis, and specific therapy. The nature of the antimicrobial therapy required both for infection prevention and treatment is closely linked to the immunosuppressive therapy being administered. A particular challenge in the transplant patient is that the antiinflammatory effects of antirejection therapy tend to obscure the manifestations of infection until relatively late in the disease process, thus putting particular emphasis on more aggressive diagnostic approaches-imaging procedures, biopsy, and new techniques for microbial detection (antigen and DNA detection). Antimicrobial therapy can be administered in three ways: therapeutically, prophylactically, and preemptively. Particularly given the propensity for adverse interactions between antimicrobial agents and cyclosporine and tacrolimus, there is a particular emphasis on prophylactic and preemptive use of antimicrobials.

Background: Organ transplant recipients who are seropositive for cytomegalovirus (CMV) and who are treated with antilymphocyte antibody (ALA) therapy have a high rate of symptomatic CMV disease. The intravenous administration of ganciclovir therapy once daily during ALA therapy decreased the incidence from 24% to 10% in patients receiving ALA as an induction therapy and from 64% to 22% in those treated for rejection. The present study was undertaken to determine whether a more intensive and sustained antiviral regimen could be more effective., Methods: From April 1995 to December 1997, all CMV seropositive renal and liver transplant recipients who received ALA therapy were treated with intravenously administered ganciclovir (5 mg/kg/day with dose adjusted for renal dysfunction) for the length of ALA therapy and then with orally administered acyclovir (400 mg three times/day) or ganciclovir (1 gm twice/day) for 3 to 4 months. The incidence of CMV viremia and of CMV disease was determined during the 6 months after completion of ALA therapy., Results: Forty-one patients (35 renal and 6 liver transplant recipients) were studied. CMV disease occurred in 2 patients (4.9%), both of whom were treated for rejection; it occurred in 1 of 21 patients (4.8%) treated with orally administered acyclovir, and in 1 of 20 patients (5%) treated with orally administered ganciclovir. The only patient who developed CMV disease in the ganciclovir group had received only 26 days of oral antiviral therapy. No CMV disease was documented in the group of patients receiving ALA therapy as induction therapy. CMV viremia occurred in three patients in the acyclovir group (14.3%) and in one patient in the ganciclovir group (5%). Among renal transplant recipients only, 1 of 35 patients developed CMV disease (2.9%) and no case of CMV disease was documented in patients treated with orally administered ganciclovir. All six patients receiving two courses of ALA therapy each were free of CMV disease. Toxicity of the regimen was minimal, and antiviral resistance did not develop., Conclusions: Preemptive antiviral therapy with intravenously administered ganciclovir during ALA therapy and then orally administered ganciclovir for 3 to 4 months provides virtually complete protection against the excessive rate of CMV disease that occurs in CMV seropositive allograft recipients receiving ALA therapy.

The occurrence of urinary tract infection and its clinical impact is determined, as with any infectious disease, by the interaction between the virulence of the infecting organism and the host defense mechanisms that can be mobilized. In the case of urinary tract infections, an anatomically and functionally intact kidney and urinary tract are the primary host defenses, with phagocytic function and immune mechanisms coming into play to limit the consequences of those infections. Of all the categories of immunocompromised hosts, the renal transplant patient is the one most susceptible to the direct and indirect consequences of urinary tract infections. In the first 3 months post transplant, the incidence of urinary tract infection is greater than 30%, and there is a relatively high rate of bacteremia and overt pyelonephritis of the allograft. After this time period, unless anatomic or functional derangement of the urinary tract is present, the direct clinical manifestations are far more benign. In addition to the direct effects of urinary tract infection on these patients, indirect effects are also important. These include the activation of CMV by TNF released as a consequence of a urinary tract infection and the initiation of allograft injury. Fortunately, low-dose trimethoprim-sulfamethoxazole or fluoroquinolones are safe and effective prophylactic strategies for preventing the direct and indirect consequences of urinary tract infections. Although the pathogenetic mechanisms are incompletely understood, data are emerging that AIDS patients have both an increased incidence and severity of urinary tract infection. The risk for urinary tract infections seem to be correlated with the degree of immune compromise and, perhaps, the amount of malnutrition and wasting that are present. The best strategies for preventing urosepsis in AIDS patients remain to be defined.

Although cytomegalovirus (CMV) is rarely cultured from peripheral-blood leukocytes of immunocompetent patients, it may be cultured from up to 60% of renal transplant recipients, 1 to 4 months after transplantation. During this same period, renal transplant recipients are often referred for psychiatric evaluation. Since CMV may infect the central nervous system, the relationship between isolation of CMV from peripheral-blood leukocytes (viremia) and psychiatric evaluation was investigated in 80 renal allograft recipients at the Massachusetts General Hospital. Five of 16 (31%) patients with viremia and 7 of 64 (11%) patients without viremia required psychiatric consultation (P = 0.04, two-tailed Fisher exact test). CMV viremia may be an important but treatable contributor to psychiatric symptoms in the transplant recipient.

Objective: To determine whether preemptive ganciclovir therapy administered daily during antilymphocyte antibody therapy can prevent cytomegalovirus disease in renal transplant recipients who are positive for cytomegalovirus antibody., Design: Randomized, controlled, multicenter trial., Setting: 6 university-affiliated transplantation centers., Patients: 113 renal transplant recipients who were positive for cytomegalovirus antibody., Intervention: Patients were randomly assigned to receive either 1) ganciclovir, 2.5 mg/kg body weight administered intravenously on every day that antilymphocyte antibody therapy was administered or 2) no anticytomegalovirus therapy., Measurements: Patients were observed for 6 months after completion of antilymphocyte antibody therapy for development of cytomegalovirus disease and cytomegalovirus viremia., Results: Cytomegalovirus disease occurred in 14% of patients (9 of 64) who received preemptive ganciclovir therapy and in 33% of controls (16 of 49) (P = 0.018). Cytomegalovirus was isolated from buffy-coat specimens from 17% of patients (11 of 64) receiving preemptive ganciclovir and from 35% of controls (17 of 49) (P = 0.03). Controlling for the reason (induction or treatment of rejection) for using antilymphocyte antibodies in a Cox proportional hazards model, we found that preemptive ganciclovir still protected against cytomegalovirus disease (adjusted relative risk, 0.27; 95% CI, 0.12 to 0.64). No adverse events were attributed to preemptive ganciclovir therapy during or within 6 months of its administration., Conclusions: Preemptive ganciclovir therapy administered daily during courses of treatment with antilymphocyte antibodies reduced the excessive occurrence of cytomegalovirus disease in renal transplant recipients who were positive for cytomegalovirus antibody. This approach, which links the most potent immunosuppression to intensive antimicrobial therapy, allows preventive therapy to be given to those patients at greatest risk for developing infectious complications. These patients are likely to benefit most from the preventive strategy.

Approximately 30% of patients with end stage renal disease who undergo transplantation develop renal failure as a result of their long-standing diabetes mellitus. Therefore, diabetics warrant special attention in considering the infectious disease problems associated with transplantation. The three categories that should be considered in infections affecting the diabetic renal transplant recipient are discussed in this article.

Background: Prophylaxis with low-dose trimethoprim-sulfamethoxazole has been shown to be cost-effective in the prevention of urinary tract infections, pyelonephritis, urosepsis, and pneumocystis pneumonia in renal transplant recipients. Ciprofloxacin, effective against almost all urinary tract pathogens in this patient population, represents a promising alternative prophylactic agent for patients unable to tolerate trimethoprim-sulfamethoxazole due to toxicity., Methods: We conducted a randomized, double-blind trial to compare low-dose trimethoprim-sulfamethoxazole with ciprofloxacin for the prevention of urinary tract infections in renal transplant recipients. Patients received either ciprofloxacin (250 mg) or trimethoprim-sulfamethoxazole (80 mg trimethoprim, 400 mg sulfamethoxazole) daily for 6 months following transplantation. Treatment was considered successful if patients completed the 6-month course and 3-month follow-up period without evidence of urinary tract infection or drug-related toxicities., Results: Of 103 eligible patients, 51 received ciprofloxacin and 52 received trimethoprim-sulfamethoxazole. At 6 months, treatment was successful in 75% (38 of 51) receiving ciprofloxacin and 71% (37 of 52) treated with trimethoprim-sulfamethoxazole (P = 0.87, relative risk 1.04, 95% confidence limits 0.83 to 1.33). Thirteen patients (25%) receiving trimethoprim-sulfamethoxazole withdrew from the study-4 for resistant urinary tract infection and 9 for drug-related toxicity, while 3 (6%) of the patients receiving ciprofloxacin withdrew because of drug-related toxicity (P = 0.016, relative risk of urinary tract infection or adverse event 0.24, 95% confidence limits 0.07 to 0.78). At 9 months, all 38 patients who completed the 6-month course of ciprofloxacin remained free of urinary tract infection, while an additional 4 patients who had received trimethoprim-sulfamethoxazole prophylaxis (total of 8 patients over the 9 months) developed urinary tract infections (P = 0.006, Fisher's exact test for urinary tract infection alone). Pneumocystis pneumonia occurred in a total of 7 (14%) patients who were randomized to ciprofloxacin, but 2 of the 7 had withdrawn from the study at least 2 weeks prior to the diagnosis of pneumocystis pneumonia. There were no cases of pneumocystis pneumonia in patients receiving trimethoprim-sulfamethoxazole (P = 0.006). Following completion of the study, monthly aerosolized pentamidine administered in conjunction with ciprofloxacin has provided complete protection against urinary tract infection and pneumocystis pneumonia in 30 transplant recipients unable to tolerate trimethoprim-sulfamethoxazole therapy., Conclusions: Ciprofloxacin is at least as effective as trimethoprim-sulfamethoxazole in the prevention of urinary tract infection in renal transplant recipients, and is better tolerated. Ciprofloxacin prophylaxis is associated with a higher incidence of pneumocystis pneumonia than is trimethoprim-sulfamethoxazole therapy. An uncontrolled follow-up study suggests that ciprofloxacin prophylaxis combined with monthly aerosolized pentamidine may be efficacious in preventing both urinary tract infection and pneumocystis pneumonia in renal transplant recipients.

A prospective study to investigate risk factors for CMV disease was conducted in 94 renal transplant recipients. CMV disease was defined as either unexplained fever for greater than 3 days with viremia or unexplained fever for greater than 3 days with isolation of CMV from the urine or throat wash and at least one of the following: leukopenia, elevated serum alanine aminotransferase, or biopsy-proved invasive tissue infection of the lung or gastrointestinal tract. Fifty-three patients received immunosuppressive regimens consisting of prednisone and cyclosporine, with or without azathioprine. The remaining 41 patients were treated with these agents plus OKT3 (21 received OKT3 to treat rejection, 20 received OKT3 prophylactically). Thirty-seven patients were at minimal risk of CMV disease (donor and recipient seronegative for CMV); 12 patients were at risk of primary disease (donor seropositive, recipient seronegative), and 45 were at risk of reactivation disease (recipient seropositive at the time of transplantation). The incidences of CMV disease in the 3 groups were 0%, 58%, and 36%, respectively. Although the incidence of CMV disease in patients at risk of primary disease was not influenced by the immunosuppressive regimen, immunosuppression had a profound effect on the occurrence of CMV disease in CMV-seropositive transplant recipients. The incidence of CMV disease in those receiving OKT3 was 59%; but only 21% in those who did not receive OKT3. OKT3 increased the risk of CMV disease five-fold (odds ratio 5.2 (95% confidence limits 1.4-17.5)). In the CMV-seropositive patient, OKT3 was also the most important predictor of CMV disease by multivariate analysis (P less than 0.002). A pilot study of preemptive therapy with ganciclovir (2.5 mg/kg daily during OKT3 therapy) in 17 patients decreased the incidence of CMV disease without appreciable toxicity.

The risk of infection in the transplant patient is determined by two factors: the net state of immunosuppression and the environmental exposures the patient encounters. Those infections that do occur in the transplant patient are strongly modulated by the type, intensity, duration, and sequence of immunosuppressive agents administered. A central role in the pathogenesis of all forms of infection in the transplant patient is played by the immunomodulating viruses, particularly cytomegalovirus. Prevention of infection is far better than treatment; when prevention fails and clinical disease develops, patient and allograft survival are directly related to the speed with which diagnosis is made and specific therapy instituted. In order to prevent disease, both antimicrobial prophylaxis and preemptive therapy are being increasingly employed, particularly to blunt the side effects of intensive antirejection therapy.

The term urinary tract infection encompasses a broad range of clinical entities, each with its own pathology and each requiring its own form of treatment. There are at least four different modes in which antimicrobial therapy may be prescribed for urinary tract infection: single-dose therapy aimed at patients with superficial mucosal infection; a conventional seven- to 14-day course of therapy; a prolonged four- to six-week course of therapy for patients with deep tissue infection; and low-dose prophylactic therapy. Increasingly, the response to single-dose therapy is being utilized to delineate the mode of therapy needed by a patient. Patients with underlying renal disease and/or structural abnormalities of the urinary tract are prone to the development of recurrent urinary tract infection, frequently with bacteria resistant to antimicrobial agents conventionally employed to treat the infection. There has been a steady increase, even among otherwise normal persons with urinary tract infection, in the level of antimicrobial resistance exhibited by bacterial uropathogens to the drugs commonly used to treat these infections. The quinolones in general, and ciprofloxacin in particular, appear to be very promising for the treatment of urinary tract infection. It will be important to evaluate the performance of this drug in the four different therapeutic modes and in patients with renal dysfunction or anatomic abnormalities of the urinary tract.

The clinical management of urinary tract infection has changed considerably over the last two decades due to the recognition of several important factors: All urinary tract infections are not the same; in particular, deep tissue infection of the kidney and/or prostate requires a very different form of clinical management than does superficial mucosal infection of the bladder. Consistent with these differences, it is now clear that conventional 7-14 day treatment courses are not ideal for most forms of urinary tract infections; deep tissue infection requires more intensive therapy and superficial mucosal infection needs less intensive therapy. In particular, single dose antimicrobial therapy has been a major advance in the management of the most common form of urinary tract infection--acute uncomplicated urinary tract infection of the adult female; such therapy is safe, effective, inexpensive, and the response provides useful clinical information. The recognition of the etiology of the acute urethral syndrome in most patients (true bacteriuria or Chlamydia trachomatis infection) had led to an effective therapeutic approach to this problem. A logical approach to the problem of recurrent urinary tract infection has emerged that is both cost-effective and clinically effective. Finally, a clearer picture of those populations that would benefit most from anatomical study of the urinary tract has been developed. With these advances, this most common of bacterial infections affecting man throughout his lifespan has become much easier to control.

We investigated the relation between cytomegalovirus (CMV) infection and renal-allograft dysfunction in 14 patients. In seven instances (including two successive transplants in one patient), allograft dysfunction occurred during clinically manifest, viremic CMV infection. In five of these, biopsies revealed little or no tubulointerstitial change but a distinctive, diffuse glomerulopathy characterized by enlargement or necrosis of endothelial cells and accumulation of mononuclear cells and fibrillar material in glomerular capillaries. Two of these allografts recovered their function, both with cessation of high-dose immunosuppression. Biopsies in the other 10 patients revealed predominantly tubulointerstitial changes typical of cellular rejection, and most of these patients did not have viremia. One additional patient, studied prospectively, manifested both forms of allograft injury: tubulointerstitial changes occurring two weeks after transplantation and responding to increased immunosuppression, and CMV-associated glomerulopathy occurring seven weeks after transplantation and responding to decreased immunosuppression. We conclude that viremic CMV infection can cause acute glomerular injury and that recovery may be favored by a decreased in immunosuppressants.

The incidence of infection in the renal transplant patient is directly related to the net immunosuppressive effect achieved and the duration of time over which this therapy is administered. A second major factor in the causation of infections in this population is the nosocomial hazards to which these patients are exposed, ranging from invasive instrumentation to environmental contamination with Aspergillus species, Legionella pneumophila, Pseudomonas aeruginosa and other microbial pathogens. Careful surveillance is necessary to identify and eliminate such nosocomial sources of infection. The major types of infection observed can be categorized according to the time period post-transplant in which they occur: postsurgical bacterial infection in the first month after transplantation; opportunistic infection, with cytomegalovirus playing a major role, and transplant pyelonephritis in the period one to four months post-transplant; and a mixture of conventional and opportunistic infections in the last post-transplant period. Conventional infection in this late period occurs primarily in patients with good renal function who are receiving minimal immunosuppressive therapy; opportunistic infection occurs primarily in patients with poor renal function who are receiving higher levels of immunosuppression.

Urinary tract infection (UTI) during the four months after renal transplantation occurs in 30%-40% of recipients at the Massachusetts General Hospital and is often associated with gram-negative bacteremia, significant graft dysfunction, and relapse. Of these "early" UTIs, 90% affect the graft itself. In a randomized trial of prophylaxis of UTI with trimethoprim-sulfamethoxazole (TMP-SMZ), 52 consecutive allograft recipients received either no prophylaxis or one TMP-SMZ tablet (160 mg of TMP plus 800 mg of SMZ) daily for four months, beginning on removal of the Foley catheter (usually during the first four days after transplantation). Three of the first five patients given TMP-SMZ developed oral candidiasis; they and all subsequent recipients of TMP-SMZ were given oral mycostatin throughout prophylaxis. Two of 26 patients (8%) taking TMP-SMZ developed UTIs; 10 of 26 patients (38%) not taking the drug developed UTIs with evidence of graft infection (P less than 0.05). The two groups were comparable in age, sex, history of UTI before transplantation, type of donor, type of ureteral anastomosis, and antibiotic use for other types of infection. Only one complication, a skin eruption, was observed among patients taking TMP-SMZ and mycostatin. It is concluded that TMP-SMZ is well tolerated and effective prophylaxis in this setting.

With the advances that have occurred over the last two decades in the prevention and treatment of bacterial and fungal infection, viral infection has been recognised as an important problem in renal transplant patients. Four groups of viruses--the herpesviruses, hepatitis viruses, papovaviruses, and adenoviruses - appear to have a particular impact on this patient population, especially the first two of these. The effects of these viruses can be categorised as follows: the production of infectious diseases by the virus itself; the production of an immunosuppressed state that predisposes to opportunistic superinfection; the production of a unique form of allograft injury; and the production of malignancy. It is the recognition of these last three categories of viral effect that has led to a reawakening of interest in these agents in recent years. In particular, the interaction among rejection, innovative forms of immunosuppression, and reactivated viral infection in the pathogenesis of malignant disease, which occurs at a markedly increased rate in this patient population, offers a major frontier of human biology whose importance extends far beyond the renal transplant population.

The problem of human immunodeficiency virus (HIV) infection and that of the acquired immunodeficiency syndrome (AIDS) are becoming increasingly important in clinical transplantation. The epidemiologic characteristics of this infection are important factors in determining the impact of this infection on transplant patients: in particular, the presence of a transmissible virus in the blood, tissues, and body fluids of even asymptomatic individuals for prolonged periods; the role of lymphocyte activation in accelerating the pace and effects of HIV infection, with the transplant patient having more reasons for lymphocyte activation than other patient categories; and the possible contributions of immunosuppressive therapy to the course of HIV infection. Already, at least 20 cases of primary HIV infection conveyed by infected blood or allografts at the time of transplant have been noted; a similar number of transplants have been carried out in asymptomatic carriers of the virus. The initial impression is that the course of HIV infection in these patients is accelerated, but information is incomplete and an international registry for the study of this problem has been established.

The combination of amoxicillin and potassium clavulanate will soon be marketed in 2:1 and 4:1 fixed ratio dosage forms. In vitro and in vivo evidence suggests that clavulanic acid, a potent inhibitor of many bacterial beta-lactamase enzymes, will increase the spectrum of amoxicillin to include, at achievable serum concentrations, Haemophilus influenzae, H. ducreyi, Neisseria gonorrhoeae, Staphylococcus aureus and Branhamella catarralis and, at achievable urine levels, many beta-lactamase-producing strains of E. coli, Klebsiella, Proteus and Citrobacter. Both amoxicillin and clavulanic are well absorbed after oral administration, reach peak serum levels in 40-120 min and have similar half-lives of 45 to 90 min. This combination will be suitable for the treatment of complicated urinary tract infections, otitis media, sinusitis and respiratory tract infections. However, precise recommendations for its use will need to await further clinical trials that compare amoxicillin/clavulanate to alternative therapies.

We studied the interrelation among herpes-virus infections, T-lymphocyte subsets, opportunistic infections, and renal histopathology in 28 recipients of renal allografts. All primary or reactivated herpesvirus infections occurring in the first three months after transplantation in recipients of cadaveric grafts accompanied persistent inversions in the ratio of OKT4 (helper/inducer) to OKT8 (cytotoxic/suppressor) lymphocytes. In the less heavily immunosuppressed recipients of organs of living related donors, these inversions were seen only in association with clinically apparent cytomegalovirus infections. Five of seven opportunistic infections occurred in patients with OKT4/OKT8 ratios of less than 1.0. Biopsy specimens from patients with renal dysfunction occurring in association with a low OKT4/OKT8 ratio frequently revealed glomerular damage rather than acute cellular rejection. Monitoring of T-lymphocyte subsets provides early evidence of herpesvirus infections and identifies patients at increased risk for opportunistic infection after renal transplantation.