Oral valgancyclovir versus intravenous gancyclovir for cytomegalovirus prophylaxis in kidney transplant recipients.

BACKGROUND: Prophylaxis against cytomegalovirus (CMV) is a regular practice in organ transplantation. Oral valgancyclovir appears to be an interesting alternative to the usual intravenous form. PATIENTS AND METHODS: We prospectively compared the response of intravenous gancyclovir for 2 weeks (GAN; n=41) to oral valgancyclovir for 2 weeks (VAL2w; n=23) or 3 months (VAL3m; n=46) in kidney transplant recipients receiving induction immunosuppression. CMV antigenemia assay and/or polymerase chain reaction (PCR) were used for viral detection. Patients were followed for a minimum of 6 months posttransplantation. SPSS software was used for statistical analysis using a cutoff of significance as P<.05. RESULTS: There was no statistical difference in the demographic features among the study groups. However, human leukocyte antigen (HLA) match was better in the VAL3m group and the patients of this group received less ATG induction immunosuppression (41.3%) compared with the GAN group (100%). The incidence of acute rejection was not different among the study groups. There was a higher incidence of fever with positive CMV tests in the VAL2w group (P=.035) compared with the other groups, while leukopenia with a negative CMV test was significantly higher in the VAL3m group (P=.04). The incidence of CMV disease was higher in the VAL2w group (30.4%) compared with the GAN group (14.6%) or the VAL3m group (8.7%). Renal function was significantly worse in the VAL2w group at 3 and 6 months (P=.011 and .02, respectively). CONCLUSIONS: Three months oral valgancyclovir prophylaxis for CMV was a more effective regimen compared with intravenous gancyclovir for 2 weeks. Shorter courses were associated with a higher incidence of CMV infection and poorer graft function. Leukopenia observed in patients receiving valgancyclovir may be a drug-related side effect.

Genotypic characterization of rotaviruses and prevalence of serotype-specific serum antibodies in children in Kuwait.

There are no data on the serotypes of rotaviruses prevalent in Kuwait, which has a large expatriate population and hence a focal point for transmission of pathogens. The serotype information will contribute to the fund of knowledge on the world epidemiology of rotavirus serotypes and will predict the outcome of vaccination in Kuwait. Of the 75 rotavirus-positive samples from 172 children (aged <5 years) with severe diarrhoea, 69 were genotyped. The distribution of genotypes was G1 (63.8%) followed by G9 (10.2%), G2 (7.3%), G4 (7.3%) and G3 (4.4%). Among the P types, P[8] was the most common type found across all G types. By fluorescent focus neutralization test, serum antibodies to genotypes G1 (94%), G4 (68%) and G9 (46%) were found in 120 other children. These results show that G1 is the predominant serotype in Kuwait and that a vaccine that contains G1 will be most effective.

Significance of atypical pathogens among community-acquired pneumonia adult patients admitted to hospital in Kuwait.

OBJECTIVES: The aim of this study is to determine the microbial etiology and severity of community-acquired pneumonia (CAP) in Kuwait. SUBJECTS AND METHODS: The severity of consecutive adult CAP cases admitted to 3 hospitals over a 1-year period was classified according to the Pneumonia Outcome Research Team (PORT) severity index. The microbial etiology was determined using standard methods for bacteria and serological tests for atypical and viral pathogens. RESULTS: The study population was 124 of the 135 admissions; 63 female, 61 male; mean age 41.3+/-18 years. The severity class distribution was: class I 31%, class II 37%, class III 17%, class IV 13%, and class V 2%. Etiological agents were identified from 44 patients (35%), with one pathogen in 31 (25%), two in 9 (7%), and three or more in 4 (3%). The most common pathogens identified were: Mycoplasma pneumoniae in 14 patients (11%), Legionella pneumophila in 10 (8%), Chlamydia pneumoniae in 8 (6%), influenza B virus in 8 (6%), influenza A virus in 5 (4%), Haemophilus influenzae in 4 (3%), Streptococcus pneumoniae in 3 (2%), Staphylococcus aureus in 3 (2%), gram-negative enterobacteria in 5 (4%), Moraxellacatarrhalis in 2 (2%), and viruses in 4 (3%). The yields from laboratory tests were 48% for paired serology, 20% from adequate sputum sample, and 3% from blood culture. CONCLUSION: Our study shows that a large percentage of mild CAP cases are admitted to hospitals in Kuwait. Atypical pathogens have a significant role in the etiology of CAP. There is overtreatment of CAP with a combination treatment consisting mainly of third-generation chephalosporins and macrolides.

Cytomegalovirus prophylaxis with ganciclovir in kidney transplant recipients receiving induction antilymphocyte antibodies.

BACKGROUND: Cytomegalovirus (CMV) is one of the serious viral infections after organ transplantation, especially in patients receiving anti-lymphocyte antibodies. Prevention of the infection using antiviral chemotherapy (ganciclovir) has gained interest in the transplant community due to the availability of quantitative methods for viral detection and monitoring. METHODS: Forty-six CMV seropositive kidney transplant recipients were assigned to receive induction immunosuppression with anti-thymocyte globulin (ATG, Fresenius). Prophylactic intravenous ganciclovir was administered for 2 weeks at a dose of 5 mg/kg/d (adjusted to kidney function) starting from the day of surgery. Patients were monitored regularly for CMV infection or disease over 1 year posttransplant. The time to CMV manifestation, the number of antigenemia assay-positive cells, the clinical severity of infection, the incidence of acute rejection, the graft function, and the duration of hospital stay were evaluated. This group was compared to a historical matched control cohort (n = 37) transplanted earlier who did not receive prophylactic ganciclovir. RESULT: The incidence of CMV disease was significantly less among the prophylaxis than the control group (6/46 patients [13%] vs 16/37 patients [43.2%], P = <.004). The time to develop CMV manifestations was much longer in the prophylaxis group than in the control group (median 92 vs 32 days, P

Correlation between CMV genotypes, multiple infections with herpesviruses (HHV-6, 7) and development of CMV disease in kidney recipients in Kuwait.

The possible correlation between cytomegalovirus, human herpesvirus types 6, 7 and cytomegalovirus-related clinical symptoms was studied in kidney transplant patients in Kuwait. Cytomegalovirus infection was diagnosed using the pp65 antigenemia assay. DNA of cytomegalovirus was detected by nested polymerase chain reaction (nested-PCR). PCR was also used to amplify the genes coding for structural proteins of human herpesvirus-6 (240 bp) and human herpesvirus-7 (186 bp). Glycoprotein B genotypes of cytomegalovirus were determined by restriction fragment length polymorphism. The average number of cells positive for cytomegalovirus pp65 antigen showed a steady increase with the severity of the cytomegalovirus-related symptoms. Furthermore, cytomegalovirus pp65 antigen positivity was significantly more frequent among recipients of cadaver kidney (45.5%) than among those who received live related kidneys (22.6%). Cytomegalovirus gB genotype 1 was detected more frequently (P<0.036) in recipients with live related donor kidney (38%) than in patients of cadaver kidney (13%). The genome of human herpesvirus-6 was detected at the same rate in patients with or without cytomegalovirus-related symptoms. However, the genome of human herpesvirus-7 was detected significantly more frequently (P<0.0001) in asymptomatic patients (41.7%) than in recipients with symptomatic cytomegalovirus infection (17%). We conclude that cytomegalovirus gB genotypes are not associated with the outcome of a cytomegalovirus infection in kidney transplant patients, that human herpesvirus-6 does not play a role in cytomegalovirus pathogenesis and that the role of human herpesvirus-7 in cytomegalovirus-related morbidity in kidney recipients remains unclear.

Seroprevalence of three emerging arboviral infections in Kuwaiti nationals.

Diseases caused by dengue, sandfly fever and hanta viruses pose a major health risk in many countries. We determined the threat of these arboviral infections through a serologic using enzyme linked immunosorbent assay (ELISA) based tests. Hantavirus-specific antibodies were also detected using immunofluorescence. Of 499 samples tested for dengue virus IgG antibodies l4% were as positive for dengue positive by all the ELISA tests. Among the 42 showing strong IgG reactivity, only 1 was positive for dengue virus IgM antibodies. All samples tested for IgG antibodies to sandfly fever virus were negative. Hantavirus antibodies were detected in 11% of the 46 samples from high-risk individuals. The low prevalences suggest that at present these infections are not a serious problem in Kuwait.

Seroprevalence of three emerging arboviral infections in Kuwaiti nationals

Diseases caused by dengue, s and fly fever and hanta viruses pose a major health risk in many countries. We determined the threat of these arboviral infections through a serologic using enzyme linked immunosorbent assay [ELISA] based tests. Hantavirus-specific antibodies were also detected using immunofluorescence. Of 499 samples tested for dengue virus IgG antibodies l4% were as positive for dengue positive by all the ELISA tests. Among the 42 showing strong IgG reactivity, only 1 was positive for dengue virus IgM antibodies. All samples tested for IgG antibodies to s and fly fever virus were negative. Hantavirus antibodies were detected in 11% of the 46 samples from high-risk individuals. The low prevalences suggest that at present these infections are not a serious problem in Kuwait

Hantavirus-specific antibodies in rodents and humans living in Kuwait.

Hantaviruses are found in widely scattered areas of the world and are transmitted by inhalation of virus-contaminated aerosols of rodent excreta. The present study was undertaken in Kuwait to investigate the serological evidence for hantavirus infection in rodents and humans. Sera were collected from 283 wild rodents and 183 human subjects (46 Kuwaitis and 137 non-Kuwaitis). The rodent sera were investigated for the presence of antibodies against the Seoul and Puumala strains of the hantaviruses by enzyme-linked immunosorbent assay and immunofluorescence technique using the virus-infected Vero E6 cells. The findings showed the presence of anti-hantavirus antibodies in seven out of the 283 (2.8%) rodents. Antibodies against the Seoul strain were present in six (2.1%) and against the Puumala strain in three (1%) rodents. Further, it was observed that three out of 84 (3.6%) of the Rattus norvegicus and four out of 174 (2.3%) Mus musculus had anti-hantavirus antibodies. Two rodents belonging to species Mus musculus had antibodies against both strains of the hantaviruses. Out of 183 human sera, 13 (7%) were positive for hantavirus antibodies. Among the Kuwaitis 5/46 (11%) and among the non-Kuwaitis 8/137 (6%) were positive for the hantavirus antibodies. Antibodies to both Puumala and Hantaan strains were detected in Kuwaitis as well as in non-Kuwaitis. Although no human case of hantavirus illness has yet been reported in Kuwait, the serological evidence of infection suggests a constant vigil.

A study of dengue imported to Kuwait during 1997-1999.

This study was carried out on sera from 210 patients in Kuwait in 1997-1999. All of the patients were suffering from febrile illness and had recently visited dengue- (DEN) endemic areas. The sera were screened for DEN virus by inoculation into cultures of the Aedes albopictus cell clone C6/36 (virus isolation) and by IgM capture ELISA (detection of DEN virus-specific IgM antibodies). In the cell cultures, DEN virus could not be isolated from any of the patients' sera. However, sera from 19 patients were positive for DEN virus-specific IgM antibodies. All these 19 sera were tested for the presence of DEN virus-specific RNA by reverse transcription-PCR (RT-PCR) using DEN virus types-common (consensus) primers. In addition, the type of DEN virus was identified by using type-specific primers in a semi-nested PCR. The results showed that two of the 19 patients were infected with DEN virus type 2. This report of 19 patients with serological evidence of DEN infection indicates that imported DEN is a real threat to Kuwait, a country non-endemic for DEN but with a large portion of the population vacationing in DEN-hyperendemic areas during the peak DEN season and then returning to Kuwait.

Role of interleukin-12 in patients with dengue hemorrhagic fever.

Interleukin (IL)-12 has a broad range of activities including regulation of cytokine synthesis and selective promotion of Th1-type cell development. A shift from a Th1-type response to Th2-type has been suggested to be important in the pathogenesis of dengue hemorrhagic fever (DHF). This study was undertaken to investigate the possible role of IL-12 in this shift. A total of 76 patients with various grades of dengue illness and 21 normal healthy controls were tested for IL-12 levels in serum samples and IL-12 mRNA in their peripheral blood mononuclear cells. The results showed that the levels of IL-12 were the highest in patients with dengue fever (270+/-102 pg ml(-1)) followed by decreasing levels in the patients with DHF grade I (198+/-86 pg ml(-1); P<0.05) and DHF grade II (84+/-52 pg ml(-1); P<0.001). Neither IL-12 nor its mRNA could be detected in the patients with DHF grades III and IV. The cytokine appeared and reached peak levels during the first 4 days of illness, started to decline by day 5-8 and disappeared by day 9 onwards. The absence of IL-12 during severe illness and late phases of the disease may be responsible for the shift to a Th2-type response and thus for the pathogenesis of DHF.

The use of flow cytometry for the detection of CMV-specific antigen (pp65) in leukocytes of kidney recipients.

Flow cytometric assay (FCA) was used to detect a cytomegalovirus (CMV) specific antigen (pp65) in CMV-infected fibroblast cells and in leukocytes of kidney recipients. FCA distinguished clearly between the infected and non-infected fibroblast cells. Regarding transplant patients, the FCA was positive when the number of antigenemia assay (AA) positive cells was five or more per 5 x 10(4). Moreover, the percentage of antigenemia-positive cells by FCA correlated well with symptomatic CMV infections.

Th1-type cytokines production is decreased in kidney transplant recipients with active cytomegalovirus infection.

Cytomegalovirus (CMV) infection is a major complication after kidney transplantation. Despite antiviral therapy the infection contributes significantly to high morbidity. The present study was aimed at determining: (a) the stimulation index (S.I.) of phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) and (b) the levels of Th1- and Th2- related cytokines in kidney transplant recipients with and without active CMV infection. Thirty-five patients with, and 44 without active CMV infections, as diagnosed by a CMV antigenemia assay, were inducted into this study. After PHA stimulation of PBMC from patients, stimulation index (S.I.) was determined by radioactive thymidine uptake while the production of Th1-type cytokines (interleukin-2 [IL-2], interferon-gamma [IFN-gamma], and tumor necrosis factor-alpha [TNF-alpha]) and Th2-type cytokines (IL-4, IL-10) were measured by enzyme-linked immunosorbent assay. PBMC of patients with active CMV infection showed significantly lower S.I. values than patients without an ongoing CMV infection (P <.0001). Levels of Th2-type cytokines in CMV-infected and uninfected kidney recipients were similar; however, the levels of the Th1-type cytokines were significantly lower in CMV-infected patients. Low levels of Th1-type cytokines seem to correlate well with active CMV infection in kidney recipients.

The prevalence of antibody to human parvovirus B19 in pregnant women in Kuwait.

Infection with parvovirus B19 during pregnancy is known to be associated with various fetal damage, such as aplastic anemia and hydrops fetalis. Our objective was to study the seroprevalence of parvovirus B19 in the obstetric population in Kuwait and to compare this with that in the adult population in other regions. Blood samples from 1047 pregnant women were used in this prospective study. Information regarding patient's age, parity, nationality and symptoms was obtained at the time of collection of the sample. Blood was tested for IgG and IgM antibodies specific for parvovirus B19 using the ELISA technique. The overall prevalence for IgG and IgM was 53.3 and 2.2%, respectively. IgG seropositivity was higher in non-Kuwaiti women, while IgM antibodies was more frequent in Kuwaiti women. A total of 17.4% of the acutely infected patients were symptomatic. Prevalence of parvovirus B19 infection in Kuwait is comparable with that in the other countries.

Sequential production of cytokines by dengue virus-infected human peripheral blood leukocyte cultures.

The study was undertaken to elucidate the sequence of appearance of T helper (Th)1- and Th2-type cytokines in human peripheral blood leucocyte cultures infected in vitro with dengue type 2 virus. Commercial sandwich enzyme-linked immunosorbent assay kits were used to assay the levels of tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin (IL)-2, IL-4, IL-5, IL-6, and IL-10 in culture supernatants. Culture supernatants were also screened for the cytotoxic factor and the dengue virus titres determined. The cytokines that appeared in the culture supernatants on the first day post-infection (p.i.) were cytotoxic factor, TNF-alpha, IL-2, and IL-6; their levels were highest on the second day p.i. IFN-gamma appeared on the second day with a peak on the third day p.i. The levels of these cytokines declined quickly, except for human cytotoxic factor (hCF) and IL-2. The cytokines that appeared later were IL-10 and IL-5 on the fourth day and IL-4 on the sixth day p.i. Dengue virus replicated in the peripheral blood leucocyte (PBL) cultures and was present throughout the course of the study. The findings of the present study show that dengue virus induced a predominant Th1-type cytokine response during the first 3 days of infection of PBL cultures that was replaced by a Th2-type response later.

Immunologic factors contributing to the initiation of labor--lymphocyte reactivity in term labor and threatened preterm delivery.

To obtain data on the immunologic events during labor, we investigated cytotoxic activity, progesterone-prostaglandin F2 alpha and prostaglandin E2 sensitivity of the lymphocytes in late pregnancy at early and late stages of labor and in the puerperium. In an attempt to investigate common determinants between the behavior of lymphocytes during labor and threatened preterm delivery, the same parameters of lymphocytes obtained from women with threatened preterm delivery were tested in parallel. At the beginning of labor, cytotoxic activity of the lymphocytes significantly increased and remained at a high level till the end of labor. A negative correlation (r = -0.803) was found between the increase of cytotoxicity and the duration of labor. High progesterone sensitivity of pregnancy lymphocytes decreased while low sensitivity to prostaglandin E2 increased during labor. Sensitivity of the lymphocytes to prostaglandin F2 alpha was similar in all of the groups examined. Except for prostaglandin E2 sensitivity all parameters of the lymphocytes obtained from women with threatened preterm delivery were similar to those of lymphocytes obtained during labor.

ELISA detectable virulence marker antigen of enteroinvasive Escherichia coli is coded by a 140 megadalton plasmid.

The ELISA reactive virulence marker antigen, characteristic of enteroinvasive Escherichia coli and virulent Shigella, expressed in an E. coli K-12 recipient after the 140 Md plasmid of an enteroinvasive E. coli strain had been introduced into it. Similarly to the epithelial cell penetration and Congo red binding capacities--known to be coded by the above plasmid--the virulence marker antigen expressed also only at 37 degrees C but not at 30 degrees C. These data suggest the plasmid coded nature of the virulence marker antigen.

The mechanism of the inhibitory effect of progesterone on lymphocyte cytotoxicity: I. Progesterone-treated lymphocytes release a substance inhibiting cytotoxicity and prostaglandin synthesis.

Progesterone-treated lymphocytes (generator lymphocytes) of healthy pregnant women release a nondialyzable factor that inhibits both cytotoxic activity and prostaglandin F2 alpha synthesis of test lymphocytes. Production of this factor is blocked by protein synthesis inhibitors (cycloheximide and actinomycin D). Sodium dodecylsulfate polyacrylamide electrophoresis of the partially purified material revealed a main 34,000 MW protein band. Progesterone-treated lymphocytes of pregnant women showing clinical symptoms of threatened preterm delivery (risk group) failed to release this substance.

The mechanism of the inhibitory effect of progesterone on lymphocyte cytotoxicity: II. Relationship between cytotoxicity and the cyclooxygenase pathway of arachidonic acid metabolism.

In the previous paper we have demonstrated that progesterone-treated lymphocytes of healthy pregnant women produce a 34,000 MW protein that inhibits cytotoxic activity and prostaglandin F2 alpha synthesis. Since recently it has been shown that certain leukotrienes have a stimulatory effect on natural killer activity, in this study an attempt was made to determine whether there is a relationship between cytotoxicity and PGF2 alpha synthesis or if alterations in the values of these parameters are independent. Arachidonic acid increased cytotoxic activity of healthy pregnant women's peripheral blood mononuclear cells (PBMC) in a concentration-dependent manner. Exogenous arachidonic acid was able to counteract the blocking effect of the above-mentioned protein produced by progesterone-treated lymphocytes. To determine whether the products of the cyclooxygenase or the lipoxygenase pathway of arachidonic acid metabolism are responsible for increased cytotoxicity, both enzyme systems were blocked separately. Both indomethacin and the lipoxygenase inhibitor BW 755C reduced cytotoxicity in a dose-dependent fashion. However, the lipoxygenase inhibitor prevented prostaglandin synthesis to the same extent, or even more than indomethacin, in all concentrations used; so, its blocking effect cannot be considered as supportive evidence for the role of leukotrienes in cytotoxicity. On the other hand, lipopolysaccharide, with a selective stimulatory effect on prostaglandin synthesis, increased cytotoxicity. Lipopolysaccharide had no effect on progesterone-pretreated PBMC. The above data allow the assumption that besides leukotrienes, cyclooxygenase products may also increase cytotoxicity.