Serologic association of human herpesvirus eight with posttransplant Kaposi's sarcoma in Saudi Arabia.

BACKGROUND: This study investigates the association between human herpesvirus eight (HHV8) and Kaposi's sarcoma (KS), the most common cancer occurring in renal transplant recipients in Saudi Arabia. METHODS: A cross-sectional study of seroreactivity to HHV8 antigens in posttransplant KS patients from a tertiary care hospital in Riyadh, Saudi Arabia, and in control subjects without KS was conducted. Seroreactivity rates were determined using immunoblotting assays to detect antibodies to two lytic cycle HHV8 antigens: p40, an antigen found in infected cells, and sVCA, an HHV8-encoded small viral capsid antigen expressed in Escherichia coli. RESULTS: Antibodies to HHV8 p40 and sVCA were present in a significantly higher proportion of renal transplant patients with KS (13 of 14 patients) compared to renal transplant patients without KS (5 of 18; P<0.001) and compared to other control individuals (6 of 44; P<0.001). HHV8 seroreactivity was more common among patients with renal failure (28%) than among other control groups (7%). CONCLUSIONS: The serologic results provide evidence of a strong association between HHV8 and posttransplant KS in Saudi Arabia.

PIP: In Saudi Arabia, Kaposi's sarcoma occurs in 4.1% of renal transplant recipients and accounts for 70% of malignancies in this group. Human herpes virus 8 (HHV8) has been identified in the DNA of many of these patients. The association between HHV8 and Kaposi's sarcoma was investigated further in post-renal transplant Kaposi's sarcoma patients from a tertiary care hospital (King Faisal Specialist Hospital and Research Center) in Riyadh, Saudi Arabia (n = 14), and non-Kaposi's sarcoma controls with renal transplant (n = 18), chronic renal failure (n = 14), other cancers that did not affect renal function (n = 15), and healthy volunteers (n = 15). The median time from transplant to Kaposi's sarcoma was 13 months. A serum sample was assumed to have antibodies to HHV8 if antibody to either p40 or sVCA was detected. The prevalence of HHV8 seroreactivity was 13/14 (93%) in cases, 5/18 (28%) in renal transplants without Kaposi's sarcoma, and 11/62 (18%) in the aggregate control group. HHV8 seroreactivity was significantly more common (p 0.001) among transplant patients with Kaposi's sarcoma than those without this cancer (odds ratio, 33.80; 95% confidence interval, 2.96-904). These findings suggest an etiologic link between HHV8 and Kaposi's sarcoma presumably due to immunologic or cellular factors that influence host-virus interactions.

Kidney transplantations at King Faisal Specialist Hospital and Research Centre.

During the five year period from 1987G to 1991G, 161 kidney transplantations were performed at King Faisal Specialist Hospital and Research Centre (KFSH&RC); 79 from cadaveric donors (CD) and 82 from living related donors (LRD). All cadaveric kidneys except one were harvested within Saudi Arabia and 67% were from Saudi nationals. The immunosuppresive protocol was a triple drug regimen comprising cyclosporin-A (CyA), azathioprine (Aza), and prednisone. The actuarial graft survival rates at one and three years were 85% and 76% for the cadaveric donor transplants and 96% and 91%, respectively for the living related donor transplants (P<0.01). The corresponding patient survival rates for cadaveric donor transplants (CDTxs) were 97% and 94% and for the living related donor transplants (LRDTxs), 99% and 97% (NS). These results compare well with the best results in the Western world. The most serious surgical complications were vascular thromboses (five cases) and infections of the arterial anastomosis line with bleeding (two cases), all leading to loss of the cadaveric graft. The most common causes of death were virus infection, varicella, cytomegalovirus, and hepatitis B and C. The organ donation rate, from cadaveric donors as well as living related donors, is stil low in Saudi Arabia. Lack of organs is the main obstacle to an expansion of this promising transplantation activity. Continuous education of the multinational medical profession as well as the lay population is necessary to improve the situation.

Urinary tract infection due to Rahnella aquatilis in a renal transplant patient.

Rahnella aquatilis is an unusual gram-negative rod belonging to the family Enterobacteriaceae. It inhabits fresh water and is rarely isolated from clinical specimens. We report the case of a urinary tract infection caused by this organism in a renal transplant patient.

Factors predictive of post-transplant erythrocytosis.

Ninety-three patients with PTE (that is, hematocrit 51% or greater) were identified among 431 renal transplant recipients, an incidence of 21.6%. Thirty-eight patients underwent blood volume measurements, and 22 of these had high red cell volume and therefore were considered to have true PTE. To analyze factors predictive of erythrocytosis, a control group with normal hematocrit was randomly selected from our renal transplant population and compared with the 93 patients with PTE, and with the 22 who had true PTE. Using step-wise logistic regression analysis, we identified three variables that were consistent predictors of PTE. In order of significance, the serum creatinine value at the onset of PTE appears to most strongly predict the occurrence of PTE (P less than 0.0001). As creatinine value increases, the probability of PTE decreases. Next was immunosuppression, where double immunosuppressive therapy was associated with a greater probability of PTE than triple therapy (P less than 0.0001). The overall incidence of PTE in patients on double therapy was 34%, while that for those on triple therapy 10.4%. Last was duration of dialysis for which increasing values correspond to increasing probability of PTE (P = 0.004). Comparison of the serum erythropoietin (EPO) levels for patients and controls yielded a nonsignificant result (P = 0.2507 and P = 0.383 for all patients with PTE and true PTE, respectively), and therefore EPO levels were inappropriately elevated for the level of hematocrit in the PTE group. Only the number of rejections and duration of follow-up (r = -0.3507) were significantly correlated with EPO (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Mycobacterial infection after renal transplantation--report of 14 cases and review of the literature.

During a nine-year period, 14 cases of mycobacterial infection (tuberculosis) developed in 403 renal transplant recipients at the King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia, an incidence of 3.5 per cent. The annual incidence of tuberculosis was about 50 times higher than that in the general population. Infection was disseminated in nine (64.3 per cent), pulmonary in four (28.6 per cent), and genitourinary in 1 (7.1 per cent). In one patient tuberculosis was transmitted by the donor's kidney. The clinical manifestations were often ill-defined and not different from that in the normal host. Cultures from all patients grew Mycobacterium tuberculosis; concomitant infection with other organisms was present in five patients (35.7 per cent). Two of 18 patients (group 1) with positive pretransplant tuberculin skin test developed tuberculosis after transplantation (11 per cent), and neither received isoniazid prophylaxis; three of 70 patients (group 2) with negative skin tests developed tuberculosis after transplantation (4.3 per cent). The difference between the two groups was not statistically significant. Review of all published cases of mycobacterial infections in renal transplant recipients revealed 130 cases. Tuberculosis was disseminated in 38.7 per cent, pulmonary in 40.2 per cent, cutaneous in 12 per cent, and miscellaneous in 9.4 per cent. Atypical mycobacteria were responsible for 29 per cent of disseminated infections, 8 per cent of pulmonary infections and all cases of cutaneous and articular tuberculosis. Invasive procedures were needed to establish the diagnosis in 21 of 33 disseminated cases but in only three of 47 cases of pulmonary tuberculosis (p less than 0.0001). The mortality rate from disseminated disease was 37 per cent and from all other forms of tuberculosis was 11 per cent (p less than 0.005). These findings (1) confirm the higher incidence of tuberculosis in renal transplant recipients, compared to the general population; (2) suggest that pretransplant skin testing probably has little value in identifying patients at risk; (3) show that disseminated tuberculosis is common after renal transplantation and requires invasive procedures for diagnosis; (4) confirm that the donor kidney may be an important source of infection; and (5) indicate that concomitant infection with other organisms is common.

Kaposi's sarcoma: the most common tumor after renal transplantation in Saudi Arabia.

Between September 1975 and November 1986, 263 renal transplant recipients at the King Faisal Specialist Hospital and Research Center were followed; 82 procedures were done by the authors using live related donors. Among the 263 patients, 14 cases of Kaposi's sarcoma were identified, an incidence of 5.3 percent compared with an incidence of 0.4 percent in renal transplant recipients from Western countries. In addition, two more patients had other types of tumors. Thus, Kaposi's sarcoma represents 87.5 percent of tumors in the King Faisal Hospital renal transplant population, in contrast to 3.7 percent in the Cincinnati Transplant Tumor Registry. The mean period between transplantation and diagnosis of Kaposi's sarcoma was 12.5 months (range, one to 37 months). Eleven patients were Saudis and three were other Arab nationals. Seven of the 11 Saudi patients were from the southwestern region of the country. Cytomegalovirus titers were not elevated in six of 10 patients. Results of tests for human immunodeficiency virus were negative in seven of eight patients. HLA-A2 antigen frequency was significantly increased in the King Faisal Hospital renal transplant patients with Kaposi's sarcoma as compared with a control population (83.3 percent versus 43.6 percent, p value = 0.006 [P = 0.06 with Bonferroni adjustment]), and increased, though nonsignificantly, compared with the live related kidney transplant recipients without Kaposi's sarcoma (83.3 percent versus 49.4 percent, p value = 0.058 [P = 0.58 with Bonferroni adjustment]), suggesting a genetic predisposition to Kaposi's sarcoma in these patients.