Cytomegalovirus genotypes gB1 and gH1 are the most predominant genotypes among renal transplant recipients in Kuwait

BACKGROUND

The human cytomegalovirus (HCMV) is a common pathogen responsible for asymptomatic and persistent infections in healthy individuals. However, cytomegalovirus infections are a major cause of morbidity and mortality in immunocompromised patients, especially in recipients of solid-organ transplants and AIDS patients.

METHODS

HCMV DNA from 42 patients who received kidney transplants between 2004 and 2008 were subjected to polymerase chain reaction and restriction fragment length polymorphism to identify HCMV gB and gH genotypes.

RESULTS

HCMV gB1 and gH1 genotypes were the most the predominant HCMV genotypes (P < .05, P < .05, respectively). In addition, both HCMV gB1 and gH1 genotype were significantly more often associated with the development of fever with leukopenia and severe HCMV disease than other gB or gH2 genotypes. No significant differences were observed among viral loads between the HCMV genotypes among infected individuals.

CONCLUSION

This study demonstrated the prevalence and role of HCMV genotypes in infection and disease in renal transplant patients in Kuwait.

Active management of post-renal transplantation BK virus nephropathy: preliminary report

OBJECTIVE

To assess the efficacy of leflunomide, intravenous immunoglobulins, and ciprofloxacin as active treatment of postrenal transplant BK virus nephropathy (BKVN) in graft outcome at 1 year.

PATIENTS AND METHODS

Renal transplant recipients with positive results of 2 BK virus polymerase chain reaction tests of urine and blood underwent graft biopsy to confirm BKVN. If BKVN was diagnosed, antimetabolite therapy (mycophenolate mofetil or azathioprine) was changed to leflunomide therapy accompanied by a course of immunoglobulin and oral ciproflxacin.

RESULTS

Of 18 patients evaluated, 72% were men. Nine patients received cadaveric organs, with a mean of 3.6 HLA mismatches. All patients received induction thereapy (61% thymoglobulin), and 61% received antirejection therapy before BKVN was diagnosed. Maintenance immunosuppression therapy was primarily with prednisolone (94%); mycophenolate mofetil, 2 g/d (94%); and tacrolimus (61%). At baseline, mean (SD) creatinine clearance was 35.6 (11.5) mL/min/1.73(2), which decreased to 29.3 (17.3) mL/min/1.73(2) at 1 year (P = .01). Patients were divided into 2 groups of 9 each according to creatinine clearance values. In group 1, baseline value was 44.5 (6.6) mL/min/1.73(2), compared with 25.36 (7.8) mL/min/1.73(2) in group 2, which decreased to 42.66 (12.8) mL/min/1.73(2) (P = .23) and 16.76 (9.0) mL/min/1.73(2) (P = .009), respectively, at 1 year. Three grafts (16.7%) were lost by the end of the study, all in group 2 (P = .03).

CONCLUSION

Late diagnosis and intensive immunosuppression predispose to BKVN. Early active treatment of BKVN may improve graft outcome at 1 year posttransplantation.

Low levels of Th1-type cytokines and increased levels of Th2-type cytokines in kidney transplant recipients with active cytomegalovirus infection

BACKGROUND

Cytomegalovirus (CMV) infection is a major complication after kidney transplantation. It is clear that Th1 and Th2 cell subsets are of major importance in determining the class of immunoprotective function in infectious diseases. Given the strong influence exerted by Th1- and Th2-type immunity on the outcome of infections, we felt it important to elucidate the levels of Th1- and Th2-type cytokines to CMV-related antigens in kidney recipients and to identify antigens that play an essential role in preventing the development of CMV infection and/or disease.

METHODS

One hundred twenty subjects were followed for CMV infection by the antigenemia assay. We investigated peripheral blood mononuclear cells (PBMCs) responses to five CMV-related peptide antigens (pp65, gB, pp150, pp28, and pp38). Stimulation index was determined by radioactive thymidine uptake, while the production of Th1-type cytokines (interferon-gamma and tumor necrosis factor-alpha) and Th2-type cytokines (interleukins-4 and -10) were measured by enzyme-linked immunosorbent assay.

RESULTS

The levels of Th1-type cytokine production after stimulating PBMCs with CMV-related antigens gB and pp150 resulted in significant decreases in the levels of interferon-gamma, while pp65, pp150, and pp38 produced significant decreases in the level of tumor necrosis factor-alpha between the two groups (P < .05). For Th2-type cytokines only pp28 produced a significant increase in the level of interleukin-10 between the two groups (P < .05). Regarding the Th1:Th2 ratios, a lower Th1-bias was observed among the CMV-positive patients for PBMCs stimulated with three CMV-related antigens (pp65, pp38, and pp28).

CONCLUSION

Low levels of Th1-type cytokines and increased levels of Th2-type cytokines upon stimulation with CMV-related peptide antigens were associated with reduced cell-mediated immunity to CMV, thus seeming to correlate with active CMV infections.

Is combined pretransplantation seropositivity of kidney transplant recipients for cytomegalovirus antigens (pp150 and pp28) a predictor for protection against infection?

OBJECTIVE

This study was aimed at detecting antibodies to the antigens which may contribute to protection against cytomegalovirus (CMV) infection after organ transplantation.

MATERIALS AND METHODS

A total of 203 kidney transplant patients were enrolled in the study. Based on CMV antigenemia assay, 23 patients were antigen-positive and of the remaining 180 antigen-negative patients, 46 were selected as controls matched for age, gender and source of kidney. The 69 kidney recipients (KR) had CMV antibody due to previous infection and were followed up for a period of 6 months after transplantation for the development of active CMV infections by the antigenemia assay. Antibody responses to five CMV-related peptide antigens (pp65, gB, pp150, pp28 and pp38) were investigated by enzyme immunoassay and their presence was correlated with the results of the CMV antigenemia assay.

RESULTS

Of the five CMV-related peptide antigens, only gB antigen showed response to the antibody in 10/23 (43.5%) antigen-positive patients and 9/46 antigen-negative patients and the difference was statistically significant (p = 0.048). On the other hand, there was no significant difference in antibody responses between the antigen-positive and antigen-negative KR to the other four CMV peptide antigens (p > 0.05). However, among the antigen-positive KR there was only 1 patient who had antibodies to both pp150 and pp28 antigen, while among the antigen-negative KR, 22 of 46 (47.8%) had the antibodies (p < 0.001).

CONCLUSION

The findings suggest that the combined presence of antibodies against the pp150 and pp28 antigens may indicate a lower risk of CMV reactivation after kidney transplantation.

BK virus nephropathy in renal transplant recipients in Kuwait: a preliminary report

INTRODUCTION

BK virus nephropathy (BKVN) is a significant cause of graft loss among renal transplant recipients. The treatment outcomes of BKVN have been variably reported in the literature.

PATIENTS AND METHODS

We prospectively investigated BKV infection and BKVN among a population of renal transplant recipients with suspected BKV infection. The 42 subjects who all had acute allograft dysfunction, were categorized in three groups: those with clinical, laboratory, and histological findings that did not suggest acute rejection, drug toxicity, or obstruction (group 1, n = 24); those with findings that suggested probable acute cellular rejection but did not respond to antirejection treatment (group 2, n = 10); and those whose renal histology suggested BKVN (group 3, n = 8). Polymerase chain reaction analysis was done to detect BKV DNA in urine and blood samples from each subject. BKV DNA was detected in 19 (45%) urine samples with 11 of these subjects (26.1% of total) having BK viremia as well.

RESULTS

No evidence of BKVN was detected histologically in seven subjects with isolated BK viruria, while the others proved to be JC virus infections. Among the 11 subjects with BK viremia, eight had BKVN based on renal histology at the time of diagnosis with BKV infection, while the other three subsequently developed histological features of BKVN. BKVN developed after 5.3 +/- 2.5 (2 to 44) months after transplantation. The serum creatinine at time of BKVN diagnosis was 158.9 +/- 58 (87 to 285) micromol/L. All subjects were initially treated with a 50% reduction in immunosuppressive drug doses. Further decreases in immunosuppression were performed in all patients with close monitoring of renal function. All subjects were followed up for a of 18.2 +/- 5 (12 to 26) months. Two grafts were lost not due to BKVN, and one patient was lost to follow-up during this period. The latest serum creatinine in eight recipients is 113 + 20 (81 to 138) micromol/L, which is better than the renal function at diagnosis.

CONCLUSION

The prevalence of BKVN in suspected BKV infection was 26%. Although the study period was short (30 months), BK viremia strongly correlated with BKVN, which seemed to be successfully treated with reduction in immunosuppression.

Pattern of parvovirus B 19 infection during different trimesters of pregnancy in Kuwait

OBJECTIVE

Aims of this study were to determine the IgG and IgM seropositivity to parvovirus B19 during the three trimesters of pregnancy.

METHODS

Initially, a total of 1,047 pregnant women were included in a prospective study. Blood samples were obtained from 343, 406 and 298 cases in the first, second and third trimesters, respectively. To study the incidence of seroconversion, a second sample of blood was obtained 2-4 weeks later from the first 100 cases, who were IgG and IgM negative in the first trimester.

RESULTS

The seroprevalence of parvovirus B19 IgG and IgM was 53.3% and 2.2%, respectively. The incidence of seroconversion was 16.5%. The rate of fetal loss was 15.4% in patients with acute infection, all of which occurred in the first two trimesters.

CONCLUSIONS

The percentage of IgG positive cases is significantly higher in first and second trimesters compared to the third trimester. The seroconversion rate was 16.5%.

Pattern of parvovirus B 19 infection during different trimesters of pregnancy in Kuwait

OBJECTIVE

Aims of this study were to determine the IgG and IgM seropositivity to parvovirus B19 during the three trimesters of pregnancy.

METHODS

Initially, a total of 1,047 pregnant women were included in a prospective study. Blood samples were obtained from 343, 406 and 298 cases in the first, second and third trimesters, respectively. To study the incidence of seroconversion, a second sample of blood was obtained 2-4 weeks later from the first 100 cases, who were IgG and IgM negative in the first trimester.

RESULTS

The seroprevalence of parvovirus B19 IgG and IgM was 53.3% and 2.2%, respectively. The incidence of seroconversion was 16.5%. The rate of fetal loss was 15.4% in patients with acute infection, all of which occurred in the first two trimesters.

CONCLUSIONS

The percentage of IgG positive cases is significantly higher in first and second trimesters compared to the third trimester. The seroconversion rate was 16.5%.

Acute lower respiratory tract infections in children in Kuwait

The features of community-acquired acute lower respiratory tract infections in 390 children are described. Half (50%) presented with bronchiolitis, 37% with pneumonia and 13% with croup. Respiratory syncytial virus was the commonest agent identified (52% of bronchiolitis, 29% of pneumonia, 51% of croup). Positive bacterial blood cultures were obtained in 10% of the patients, all except one with pneumonia. Fever (> 39 degrees C), a toxic ill look, bronchial breathing, WCC > 20 x 10(9)/l, neutrophils > 5 x 10(9)/l, platelet count > 500 x 10(9)/l, ESR > 45 mm/hr, lobar consolidation and pleural effusion were more likely to be associated with bacterial than with viral pneumonia (relative risk > 1.81; p < 0.05). In areas with limited resources, a high fever, a toxic ill look, bronchial breathing and simple laboratory tests may help to identify patients with bacterial pneumonia.

Laboratory diagnosis of acute lower respiratory tract viral infections in children

This report summarizes and compares the results of complement fixation test (CFT), virus isolation (VI), and direct immunofluorescence test (DIF) for the antigen detection of respiratory syncytial virus (RSV), influenza A virus (Flu A), and adenovirus in 62 children with acute lower respiratory tract infections (ALRI) in Kuwait. It includes, as well, CFT results for parainfluenza virus and Mycoplasma pneumoniae. Combining the three methods, a potential causative agent was identified in 56 (90 per cent) children, of whom 14 (22 per cent) had evidence of infection with more than one pathogen. RSV was most frequently identified followed by Flu A, parainfluenza, Mycoplasma pneumoniae and adenovirus. Virus isolation proved the best method for identification of RSV, Flu A, and adenovirus [identified 52 (84 per cent) cases]. DIF was sensitive for RSV detection (sensitivity 84 per cent, specificity 94 per cent), and less sensitive for Flu A (sensitivity 62 per cent, specificity 98 per cent). However, DIF was completely insensitive to adenovirus (no positives). CFT was positive for the five pathogens in 44 (71 per cent) of the population studied; therefore, almost 20 per cent of positive identifications would have been missed if VI and DIF were not done. The sensitivity and specificity of CFT for RSV, adenovirus and Flu A were 71, 75, and 31 per cent, and 94, 96, and 94 per cent, respectively. Based on the results of this pilot study, it appears that a combination of the three tests yields the best rate of virus detection. Cell culture cannot be discarded for the identification of some respiratory viruses, especially adenovirus, until better techniques, or more sensitive reagents are applied. However, since RSV is the virus most commonly involved in children with ALRI, we recommend using DIF on routine basis for diagnosis. Its results compare well with virus isolation; it is simple, rapid, and inexpensive.

Seroprevalence of human parvovirus B19 in children of a desert region

A seroepidemiological study was conducted in Kuwait to evaluate the pattern of acquisition of human parvovirus B19 by children in Kuwait and to compare it with patterns described in other regions in different climatic zones. A total of 218 serum samples from children less than 16 years of age were tested for the presence of anti-B19 IgG by enzyme immunoassay. The overall seroprevalence was 17.4%. Infants in Kuwait had low levels of maternally-acquired anti-B19 IgG (8.6%). The age of peak exposure to parvovirus B19 was 10-15 years compared with less than 10 years in England and Wales and more than 20 years in Singapore. The results of this study indicate an influence of geographic differences on transmission of parvovirus B19.

Short-term IgM and IgG antibody responses to hepatitis E virus infection

53 adult patients with acute hepatitis caused by hepatitis E virus were identified by the presence of IgM antibody to hepatitis E virus, and followed for 12 months to evaluate the kinetics of anti-HEV antibodies. All but 1 female Kuwaiti patient were expatriate workers from the Indian subcontinent, temporarily working in Kuwait. Follow-up samples obtained at 1, 3, 6 and 12 months were evaluated for IgM and IgG antibodies to hepatitis E virus. IgM-class antibodies to hepatitis E virus were detectable in 12/27 (44%) patients at 1 months, in 0/26 at 3 months, in 0/8 at 6 months and 0/6 at 12 months. IgG antibodies to hepatitis E virus were detectable in 46/47 (98%) at onset, 26/27 (96%) at 1 month, in 26/29 (90%) at 3 months, 16/16 (100%) at 6 months and 8/8 (100%) at 12 months of follow-up. This study suggests that IgM antibodies to hepatitis E virus decline rapidly after an acute infection but IgG antibodies to hepatitis E virus persists for at least 1 year in many patients.

Acute sporadic hepatitis E in Kuwait

Fifty-seven adult patients with acute hepatitis and 34 comparison patients without liver disease were evaluated using a newly developed Western blot assay for IgM antibody to hepatitis E virus. The mean age of patients with hepatitis was 32 years (range, 18-55 years); 88% were male. Among patients with acute hepatitis, hepatitis A (anti-HAV IgM positive) was diagnosed in two (4%), hepatitis B (anti-HBc IgM positive) in three (5%), and hepatitis E (anti-HEV IgM positive) in 34 (60%). One hepatitis patient had CMV IgM, another had EBV IgM, and 16 others (28%) were negative for all serologic markers of acute viral hepatitis. No patient with acute hepatitis A or B and none of the comparison patients without acute hepatitis had anti-HEV IgM. All but one case of acute hepatitis E were found among expatriates of Asian origin, and acute hepatitis E was associated significantly with recent travel to the Indian subcontinent. These data suggest that acute hepatitis E is common among foreign workers in Kuwait but that little HEV transmission is occurring directly in Kuwait.

Early pregnancy varicella and associated congenital anomalies

A case of congenital anomalies following varicella infection in the 8th week of gestation is described. Though the baby demonstrated a majority of the features characteristic of the congenital varicella syndrome and had positive immunofluorescent and ELISA tests for VZ specific antibodies, no vesicles or depigmented skin areas were seen.

Interferon and beta 2-microglobulin in patients with common variable immunodeficiency or selective IgA deficiency

The production of interferon (IFN) after stimulation of peripheral blood mononuclear cells with Sendai virus or phytohemagglutinin was studied in patients with common variable immunodeficiency (CVID) or selective IgA deficiency. Cells from CVID patients produced significantly more Sendai virus-induced (alpha) and mitogen-induced (gamma) IFN than cells from healthy control subjects. By contrast, some patients with selective IgA deficiency produced subnormal amounts of IFN-alpha. Neither IFN-alpha nor IFN-gamma was detectable in sera from the two categories of patients using radioimmunoassays with sensitivity limits of 5-10 international units per milliliter. With the aid of a more sensitive bioimmunoassay, however, antiviral activity was detected more frequently in sera from patients with CVID than in sera from control individuals. Acid treatment and absorption with anti-IFN-alpha and anti-IFN-beta sera indicated that the antiviral activity was due to IFN, with no preponderance of any particular IFN type. Determination of beta-2-microglobulin (beta 2M) concentrations revealed that CVID patients had markedly, and IgA-deficient patients moderately increased serum levels of this substance, as compared to healthy blood donors. Since IFN enhances the synthesis of beta 2M the finding of increased levels of this substance in CVID would be consistent with the observed hyperproduction of IFN. The present findings are concordant with earlier observations of increased natural killer cell activity in at least some forms of CVID and suggest that increased activity of the IFN/natural killer cell system provides a mechanism which may compensate for the defective B cell function in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)