Cost-effectiveness of the female condom in preventing HIV and STDs in commercial sex workers in rural South Africa

We assessed the cost-effectiveness of the female condom (FC) in preventing HIV infection and other STDs among commercial sex workers (CSWs) and their clients in the Mpumulanga Province of South Africa. The health and economic outcomes of current levels of male condom (MC) use in 1000 CSWs who average 25 partners per year and have an HIV prevalence of 50.3% was compared with the expected outcomes resulting from the additional provision of FCs to these CSWs. A simulation model calculated health and public sector cost outcomes assuming 5 years of HIV infectivity, 1 month of syphilis and gonorrhea infectivity, and FC use in 12% of episodes of vaginal intercourse. Delayed infections and interactions between STDs and HIV were modeled. The simulation was extended to non-CSWs with as few as one casual partner per year. We conducted multiple sensitivity analyses. The program would distribute 6000 FCs annually at a cost of $4002 and would avert 5.9 HIV, 38 syphilis, and 33 gonorrhea cases. This would save the public sector health payer $12,090 in averted HIV/AIDS treatment costs, and $1,074 in averted syphilis and gonorrhea treatment costs for a net saving of $9163. Sensitivity analyses indicate that the economic findings are robust across a wide range of values for key inputs. The program generates net savings of $5421 if HIV prevalence in CSWs is 25% rather than 50.3% and savings of S3591 if each CSW has an average of 10 clients per year rather than 25. A program focusing on non-CSWs with only one casual partner would save $199. We conclude that a well-designed FC program oriented to CSWs and other women with casual partners is likely to be highly cost-effective and can save public sector health funds in rural South Africa.

[Assessment of quality of life after antireflux surgery]

AIM OF THE STUDY

To assess the quality of life (QoL) of patients operated for gastroesophageal reflux disease (GERD).

PATIENTS AND METHODS

This prospective study included 82 consecutive patients submitted to antireflux surgery between October 1998 and January 1999. A new questionnaire was used to assess their QoL: the Gastrointestinal Quality of Life Index (GIQLI) that includes 36 items concerning 5 dimensions: symptoms, vitality, emotions, social relations and medical treatment. The series consisted of 44 men and 38 women with a mean age of 47 years (range: 18-78). QoL was assessed before and 6 months after surgery; the follow-up rate was 94% (77/82). The pre- and postoperative GIQLI scores of the study group and the GIQLY score of a control group of 110 healthy patients were compared.

RESULTS

Before surgery, the GIQLI score (90 +/- 23) was greatly impaired compared to the score (123 +/- 13) observed in the control group (p < 0.001). After surgery, the GIQLI score (110 +/- 23) increased significantly (p < 0.001), but remained statistically lower than the score of the control group (p < 0.001). The postoperative score recorded in the symptoms dimension was lower than the control group score: 55 +/- 11 versus 66 +/- 6 (p < 0.001), while no significant difference was observed in the other 4 dimensions. Univariate statistical analysis revealed that the postoperative GIQLI score (y) was correlated with the preoperative GIQLI score (x) according to the formula: y = 0.43 x + 71 (p < 0.001) and the sex of the patients, as the postoperative GIQLI score was higher in male patients (115 +/- 19) than in female patients (103 +/- 23) (p < 0.02).

CONCLUSION

The QoL of the patients was greatly improved after antireflux surgery, but remained lower than that of a control group of healthy subjects. Better patient selection should improve the results. In our series, male patients or patients with a high preoperative GIQLI score were the best candidates for antireflux surgery.

Accumulation of phosphorylated sphingoid long chain bases results in cell growth inhibition in Saccharomyces cerevisiae

Sphingolipid metabolites in mammals can function as signaling molecules with cell-specific functions. In Saccharomyces cerevisiae, phosphorylated long chain bases, such as dihydrosphingosine 1-phosphate and phytosphingosine 1-phosphate, have also been implicated in stress responses. To further explore the biological roles of these molecules, we created disruption mutants for LCB4, LCB5, DPL1, YSR2, YSR3, and SUR2. LCB4 and LCB5 encode kinases that phosphorylate long chain bases. DPL1 and YSR2/YSR3 are involved in degradation of the phosphorylated long chain bases. SUR2 catalyzes conversion of dihydrosphingosine to phytosphingosine. We adapted an HPLC method to measure intracellular concentrations of the phosphorylated long chain bases. Double mutants of dpl1 and ysr2 were inviable, whereas dpl1 ysr2 lcb4 triple mutants were viable. Further, growth inhibition associated with accumulated phosphorylated long chain bases was observed in the triple mutant dpl1 ysr2 lcb4 overexpressing LCB4 or LCB5. These results indicate that phosphorylated long chain bases can inhibit cell growth. Mutants defective in both YSR2 and SUR2, which accumulated dihydrosphingosine 1-phosphate only, grew poorly. The phenotypes of the ysr2 sur2 mutants were suppressed by overexpression of DPL1. Our results clearly show that elevated levels of phosphorylated long chain bases have an antiproliferative effect in yeast.

Induction of human cytotoxic T lymphocytes that preferentially recognise tumour cells bearing a conformational p53 mutant

The tumour-suppressor gene p53 is pivotal in the regulation of apoptosis, and point mutations within p53 are the commonest genetic alterations in human cancers. Cytotoxic T lymphocytes (CTL) recognise peptide-MHC complexes on the surface of tumour cells and bring about lysis. Therefore, p53-derived peptides are potential candidates for immunisation strategies designed to induce antitumour CTL in patients. Conformational changes in the p53 protein, generated as a result of point mutations, frequently expose the 240 epitope, RHSVV (amino acids 212-217), which may be processed differently from the wild-type protein resulting in an altered MHC-associated peptide repertoire recognised by tumour-specific CTL. In this study 42 peptides (37 overlapping nonameric peptides, from amino acids 193-237 and peptides 186-194, 187-197, 188-197, 263-272, 264-272, possessing binding motifs for HLA-A2) derived from the wild-type p53 protein sequence were assayed for their ability to stabilise HLA-A2 molecules in MHC class I stabilisation assays. Of the peptides tested, 24 stabilised HLA-A2 molecules with high affinity (fluorescence ratio >1.5) at 26 degrees C, and five (187-197, 193-200, 217-224, 263-272 and 264-272) also stabilised the complexes at 37 degrees C. Peptides 188-197, 196-203 and 217-225 have not previously been identified as binders of HLA-A2 molecules and, of these, peptide 217-225 stabilised HLA-A2 molecules with the highest fluorescence ratio. Peptide 217-225 was chosen to generate HLA-A2-restricted CTL in vitro; peptide 264-272 was used as a positive control. The two primary CTL thus generated (CTL-217 using peptide 217 225; and CTL-264 using peptide 264-272) were capable of specifically killing peptide-pulsed T2 or JY cells. In order to determine whether these peptides were endogenously processed and to test the hypothesis that mutants expressing different protein conformations would generate an alternative peptide repertoire at the cell surface, a panel of target cells was generated. HLA-A2+ SaOs-2 cells were transfected with p53 cDNA containing point mutations at either position 175 (R-->H) or 273 (R-->H) (SaOs-2/175 and SaOs-2/273). Two HLA-A2-negative cell lines, A431 and SKBr3, naturally expressing p53 mutations at positions 273 and 175 respectively, were transfected with a cDNA encoding HLA-A2. The results showed that primary CTL generated in response to both peptides were capable of killing SaOs-2/175 and SKBr3-A2 cells, which possess the same mutation, but not SaOs-2/273, A431-A2 or SKBr3 cells transfected with control vector. This suggests that these peptides are presented on the surface of SaOs-2/175 and SKBr3-A2 cells in a conformation-dependent manner and represent potentially useful target peptides for immunotherapy.

A high-performance liquid chromatographic method to measure sphingosine 1-phosphate and related compounds from sphingosine kinase assays and other biological samples

Sphingosine 1-phosphate is an intermediate of sphingosine catabolism as well as a potent signaling compound. Conditions were established for the extraction and analysis of sphingosine 1-phosphate and other sphingoid base 1-phosphates from in vitro sphingosine kinase assays and other biological samples. The sphingoid base 1-phosphates were extracted in high yield (85%) using small C-18 reverse-phase columns (LiChroprep RP-18). After the extracts were treated with 0.1 N KOH to remove glycerolipids, the sphingoid base 1-phosphates were converted to fluorescent o-phthalaldehyde derivatives that were separated by HPLC using C-18 columns with a mobile phase of methanol:10 mM potassium phosphate (pH 7.2):1 M tetrabutylammonium dihydrogen phosphate (in water) (83:16:1, v/v/v). The o-phthalaldehyde derivative of sphingosine 1-phosphate was reasonably stable (t(1/2) > or = 18 h) when EDTA was present and could be detected in picomole amounts. The HPLC retention time of the sphingoid base 1-phosphates could be shifted by adjusting the mobile phase to pH 5.5, which is useful in separating overlapping compounds (such as sphingosine 1-phosphate and 4-D-hydroxysphinganine) and in confirming the identity of sphingoid base 1-phosphates in biological samples. The extraction procedure and HPLC method facilitated assays of sphingosine kinase with different sphingoid bases as substrates and/or inhibitors and enabled the quantitation of sphingoid base 1-phosphates in human plasma, serum, and platelets as well as in strains of Saccharomyces cerevisae with mutations in sphingolipid metabolism.

Prevention of mother-to-child HIV transmission in resource-poor countries: translating research into policy and practice

Each year, an estimated 590,000 infants acquire human immunodeficiency virus type 1 (HIV) infection from their mothers, mostly in developing countries that are unable to implement interventions now standard in the industrialized world. In resource-poor settings, the HIV pandemic has eroded hard-won gains in infant and child survival. Recent clinical trial results from international settings suggest that short-course antiretroviral regimens could significantly reduce perinatal HIV transmission worldwide if research findings could be translated into practice. This article reviews current knowledge of mother-to-child HIV transmission in developing countries, summarizes key findings from the trials, outlines future research requirements, and describes public health challenges of implementing perinatal HIV prevention interventions in resource-poor settings. Public health efforts must also emphasize primary prevention strategies to reduce incident HIV infections among adolescents and women of childbearing age. Successful implementation of available perinatal HIV interventions could substantially improve global child survival.

Prevention of mother-to-child transmission of HIV in developing countries: recommendations for practice. The Ghent International Working Group on Mother-To-Child Transmission of HIV

OBJECTIVES

Different approaches to prevent mother-to-child transmission of HIV are being evaluated in developing countries. The first trials using a short regimen of zidovudine have been successful in Thailand, Côte d'Ivoire and Burkina Faso. International and local strategies are now being considered. The Ghent International Working Group on Mother-to-Child Transmission of HIV developed public health policy options to integrate these interventions into basic and maternal and child health (MCH) services.

METHODS

The following tasks were undertaken: a critical review of randomized trials; an international pooled analysis of late postnatal transmission of HIV through breastfeeding; a review of the cost-effectiveness and cost-benefit of antiretroviral prophylaxis; a feasibility assessment of preventive strategies, including a postal survey on HIV voluntary counselling and testing (VCT) of pregnant women; the identification of requirements and research priorities for prenatal, obstetric and paediatric care. These projects provided the background for a three-day workshop in Ghent, Belgium, in November 1997. Conclusions were further refined, based on 1998 research findings.

RESULTS

A summary of relevant evidence and ten public health recommendations are reported. VCT for pregnant women, a short regimen of zidovudine together with alternatives to breastfeeding currently represent the best option to reduce vertical transmission in most developing countries. The primary goal of the integrated package supporting these interventions is to alleviate overall maternal and infant morbidity and mortality.

CONCLUSION

Prevention of mother-to-child transmission of HIV should now be considered for integration into basic health and MCH services of selected countries, with the involvement of governments and donor agencies.

Ambulatory care transitioning for the rural hospital

As rural community hospitals continue their transition of health care delivery to predominantly outpatient and ambulatory services, many factors are being considered in design, planning, and operations to enact this change both efficiently and effectively. The following examines strategies that allow these changes to be incorporated successfully while maintaining the flexibility for the continued transition that these organizations will experience in the future.

Pharmacokinetics and antiretroviral activity of lamivudine alone or when coadministered with zidovudine in human immunodeficiency virus type 1-infected pregnant women and their offspring

The safety, pharmacokinetics, and antiretroviral activity of lamivudine alone and in combination with zidovudine was studied in pregnant women infected with human immunodeficiency virus type 1 (HIV-1) and their neonates. Women received the drugs orally from week 38 of pregnancy to 1 week after delivery. Neonate therapy began 12 h after delivery and continued for 1 week. Both treatment regimens were well-tolerated in women and newborns. Lamivudine and zidovudine pharmacokinetics in pregnant women were similar to those in nonpregnant adults. Lamivudine and zidovudine freely crossed the placenta and were secreted in breast milk. Neonatal lamivudine clearance was about half that in pediatric patients; zidovudine clearance was consistent with previous reports. HIV-1 RNA could be quantified in 17 of the 20 women. At the onset of labor/delivery, mean virus load had decreased by approximately 1.5 log10 copies/mL in both treatment cohorts. Although not definitive for HIV-1 infection status, all neonates had HIV-1 RNA levels below the limit of quantification at birth and at ages 1 and 2 weeks.

Protection against sexually transmitted diseases by granting sex workers in Thailand the choice of using the male or female condom: results from a randomized controlled trial

BACKGROUND

The male condom is the most effective barrier method available for protection against sexually transmitted diseases (STDs), including HIV infection. There is an urgent need to develop and evaluate other prevention methods, such as the female condom. This study estimated the additional protection against STDs offered to sex workers by giving them the option of using the female condom when clients refused to use a male condom.

METHODS

Sex establishments in four cities in Thailand were randomized into two study groups: one in which sex workers were instructed to use male condoms consistently (male condom group); and one in which sex workers had the option of using the female condom if clients refused or were not able to use male condoms (male/female condom group). Randomization was done by sex establishments, and not by individuals, to minimize sharing of female condoms across study groups. The proportion of unprotected sexual acts (defined as sexual acts in which condoms were not used, tore, or slipped in or out) and incidence rate of STDs (gonorrhoea, chlamydial infection, trichomoniasis and genital ulcer disease) were measured over a 24-week period and compared between the two study groups.

FINDINGS

Results are available from 34 sex establishments (249 women) in the male/female condom group, and 37 sex establishments (255 women) in the male condom group. Condom use was very high in both groups (97.9 and 97.3 % of all sexual acts, respectively, P > 0.05). Male condom use was lower in the male/female condom group when compared with the male condom group (88.2 and 97.5%, respectively, P < 0.001). However, this reduction in male condom use was counterbalanced by the use of female condoms in 12.0% of all sexual acts in the male/female condom group, contributing to a 17% reduction in the proportion of unprotected sexual acts in this group when compared to the male condom group (5.9 versus 7.1%, respectively, P = 0.16). Female condom use was sustained over the entire study period. There was also a 24% reduction in the weighted geometric mean incidence rate of STDs in the sex establishments of the male/female condom group compared to the male condom group (2.81 versus 3.69 per 100 person-weeks, P = 0.18).

Cost-effectiveness of antiviral drug therapy to reduce mother-to-child HIV transmission in sub-Saharan Africa

OBJECTIVE

To assess the potential cost-effectiveness of short-course antiviral regimens to prevent mother-to-child transmission (MCT) of HIV in sub-Saharan Africa.

DESIGN

Cost-effectiveness analysis.

METHODS

No intervention was compared with three regimens of twice daily zidovudine and lamivudine: regimen A, starting at 36 weeks of gestation and continuing to 1 week postpartum; regimen B, from intrapartum through 1 week postpartum; and regimen C, intrapartum only. Model inputs were estimated from published and unpublished data. Absolute percentage reductions in HIV transmission extrapolated from zidovudine monotherapy trials were estimated at 12.4, 8.6 and 4.3% for regimens A, B, and C, respectively. Outcome measures were net costs to the public sector health-care system, cost per infection averted, and cost per disability-adjusted life-year (DALY) gained. Multiple sensitivity analyses were conducted.

RESULTS

Based on the hypothetical efficacy estimates, regimen C was the most cost-effective. For a cohort of 100 women with 15% HIV prevalence, net costs to the public sector health-care systems were estimated at US$3617 for regimen A, US$ 1667 for regimen B, and US$351 for regimen C. Regimen C had a cost of US$ 1129 per HIV infection averted and a cost of US$60 per DALY. Regimens B and A cost US$2680 and 5134 per infection averted and US$143 and 274 per DALY, respectively. Cost-effectiveness declined rapidly at efficacy below 10% or HIV prevalence below 7%. Results were very sensitive to antiviral drug costs. For example, at 20% of current prices, the cost per DALY for regimen A fell to US$64, and to about US$42 for regimens B and C.

CONCLUSION

Antiviral therapy may be cost-effective compared with other health interventions if HIV prevalence is high, if clinical trials confirm estimated efficacies, and if drug prices are reduced.

Sexually transmitted disease prevalence in brothel-based commercial sex workers in Chiang Mai, Thailand: impact of the condom use campaign

One hundred and ninety five (195) brothel-based commercial sex workers (CSW) in Chiang Mai, Thailand, were screened for sexually transmitted disease (STD) between October 1994 and April 1995, prior to their enrollment in a multi-center comparative trial of the effectiveness of two strategies using male and female condoms. These CSW had a mean age of 22.2 (SD 4.3) years. Forty-seven per cent were Thai and 57.4 per cent had no formal education. Median duration of prostitution was 16 months and median cost for sexual service was 50 baht (US$ 2) per client. Ninety-four per cent of CSW reported always using condoms with clients. There were 63 (32.3%) CSW infected with at least one type of the STD screened. The prevalence of STD included chlamydial infection (16.9%), gonococcal infection (14.4%), condyloma accuminata (4.6%), moluscum contagiosum (2.6%) and trichomoniasis (1.0%). There was no statistically significant risk factor for STD found in this study. Despite an active programme for prevention of STD in CSW and the provision of free condoms, STD were diagnosed in one-third of the screened CSW in Chiang Mai. The programme needs to be strengthened by more intensive education and practice in the correct and consistent use of condoms and integrated with other STD prevention programmes.

Identification of HIV infection in pregnancy: another era

In order to be successfully implemented, some interventions to prevent vertical transmission of human immunodeficiency virus (HIV) will require prior identification of HIV-infected women. The testing and counselling of pregnant women should therefore be promoted. Promoting testing and counselling within prenatal clinics would be a good strategy; however, additional data on the social and economic implications of HIV testing are needed to demonstrate the relevance of such a strategy. Promotion of testing and counselling should be developed in collaboration with community-based organizations, non-governmental organizations and people living with HIV, in order to increase the involvement and understanding of the community at large.

Lower survival in AIDS patients receiving dapsone compared with aerosolized pentamidine for secondary prophylaxis of Pneumocystis carinii pneumonia. Study Group

A randomized, unblinded study compared aerosolized pentamidine, 300 mg every month, and dapsone, 50 mg/day, for secondary prophylaxis of pneumocystosis in 196 AIDS patients. The study was prematurely discontinued due to excess mortality in the dapsone group. After a mean follow-up of 13 +/- 6.4 months, 22 (21%) of 103 patients in the pentamidine group were dead compared with 39 (42%) of 93 receiving dapsone; the estimated mortality rates at 18 months were 24.6% and 53.1%, respectively (P < .003, log-rank test). A negative interaction was observed between zidovudine and dapsone (P < .049, interaction test of Cox model), and the mean CD4 cell count during the study was lower in the dapsone (49 +/- 61/mm3) than in the pentamidine group (83 +/- 88/mm3; P < .002, t test). The lower survival might also be related to the oxidative effect of dapsone or to the addition of iron protoxalate to dapsone in this study. These results suggest caution in using dapsone as long-term therapy in advanced human immunodeficiency virus infection, especially in those receiving zidovudine.

Use of the circular stapler in 1000 consecutive colorectal anastomoses: experience of one surgical team

BACKGROUND

This study was performed to assess the exact performance of the conventional way of stapling colorectal anastomoses. Information collected from 1000 consecutive anastomoses performed by one surgical team could be considered as reliable reference with which results obtained by new approaches could be compared.

METHODS

One thousand consecutive anastomoses were performed from 1979 to 1992. Characteristics of the procedure, intraoperative events, mortality rate, complications, and clinical outcome were detailed.

RESULTS

There were 528 men and 472 women (age range, 20 to 90 years; average age, 63 years). Anastomoses were constructed by means of a circular stapler loaded with the largest cartridge in 82.3% of the cases. Imperfections were identified during operation in 124 cases. A diverting colostomy was performed in 127 cases. Postoperative mortality rate averaged 2.2%. Clinical anastomotic leaks developed in 35 patients: in 11.4% after low stapling (less than 5 cm from the dentate line) and in 2.2% after high stapling. The presence of a diverting colostomy influenced the leakage rate in patients with very low anastomoses. Total failure rate (death, definitive colostomy) as a result of anastomotic leak was 1.6%. Among the 933 survivors who had follow-up examination, the incidence of bad functional results decreased from 10% at the first attendance to 4.3% at the last one. Transanal dilatation and restapling were required for symptomatic narrowing in three and one patients, respectively.

CONCLUSIONS

The conventional way of stapling colorectal anastomoses in reliable, but it requires strict observance of the rules for anastomosing intestine and a careful check of the stapled sutures. Results obtained by new approaches could be compared with these data.

Pyogenic and tuberculous spondylodiskitis (vertebral osteomyelitis) in 80 adult patients

Bacterial spondylodiskitis--i.e., adjacent vertebral osteomyelitis and diskitis--was studied in 80 adult patients. The infection was due to Mycobacterium tuberculosis in 31 cases (39%) and to pyogenic bacteria in 49 cases (61%). The latter pathogens included gram-negative bacilli in 16 cases (20%), Staphylococcus species in 15 (19%), Streptococcus species in 9 (11%), and Corynebacterium species in 1 (1%); the pathogens in the 8 remaining cases (10%) were not identified. Of the patients with tuberculous spondylodiskitis, 55% came from countries where tuberculosis is endemic (P < .001). Cases due to staphylococci and those due to M. tuberculosis were associated with a high frequency of previous active infection with those respective organisms at any site (47% and 42%, respectively; P < .001) and with a high rate of neurological complications (33% and 32%, respectively; P < .001). Nine patients with pyogenic spondylodiskitis (18%) but only one patient with tuberculous spondylodiskitis (3%) had diabetes mellitus (P < .05). Blood cultures were positive in 23 (56%) of the 41 cases of pyogenic spondylodiskitis due to an identified bacterium. Discovertebral needle biopsy contributed to the bacteriologic diagnosis in 29 (74%) of 39 cases.

Empiric antituberculosis treatment: benefits for earlier diagnosis and treatment of tuberculosis

SETTING

Tuberculosis may be diagnosed too late, especially in HIV-infected patients, with consequences on bacillus transmission and survival. Empiric antibuberculosis treatment (EATT) may be started before diagnosis of tuberculosis is confirmed. As rifampicin is a broad spectrum antibiotic, EATT including rifampicin may be effective in infections other than tuberculosis, leading to misdiagnosis.

OBJECTIVE

To define the efficiency criteria of EATT with or without rifampicin.

DESIGN

Between 1988 and 1991, 20 febrile patients with suspected tuberculosis (including 15 who were HIV-positive) were started on EATT in the absence of bacteriological or histological proof of tuberculosis. 10 patients (50%) received a 4-drug non-specific EATT including rifampicin, isoniazid, pyrazinamide and ethambutol, and 10 (50%), received a 3-drug specific EATT without rifampicin.

RESULTS

In 10 patients (50%), the diagnosis of tuberculosis was confirmed by positive cultures within a mean of 32 days (15-57 days) after the beginning of EATT (group TB 1). Of the 10 patients whose cultures remained negative, 4 (20%) became afebrile and showed improvement under EATT (group TB 2), and 6 (30%) remained febrile and did not improve (group No TB). Patients from groups TB 1 and TB 2 became afebrile within a mean of 11 days (1-54 days). This delay was not different between patients receiving specific or non-specific EATT. In patients receiving specific EATT, rifampicin was added to the initial 3-drug treatment after resolution of fever.

CONCLUSION

EATT appears to be a useful method for rapid presumptive diagnosis and treatment of tuberculosis.

Preparation for phase III HIV vaccine efficacy trials: methods for the determination of HIV incidence

OBJECTIVE

Accurate estimates of HIV incidence that reflect the effect of non-vaccine interventions (education, counselling, condom promotion, and possibly sexually transmitted disease treatment) and that may be provided in a Phase III vaccine efficacy trial, are needed so that vaccine trial population sample sizes can be accurately determined. In order to avoid delays in the implementation of efficacy trials, well characterized cohorts must also be developed and available to participate in such trials. We reviewed the potential study populations, the epidemiologic methods for the determination of HIV incidence (using open cohort, closed cohort, and seroprevalence data methods), and the need for the development of population cohorts in preparation for Phase III HIV vaccine efficacy trials.

SETTING

Phase III trials in developed and developing countries.

METHODS

Comparison of open and closed cohorts and those using seroprevalence data to estimate HIV incidence.

RESULTS

Open and closed cohorts each have disadvantages and advantages. However, the open cohort may be more suitable for determining estimates of HIV incidence that reflect non-vaccine interventions and for the development of a well characterized cohort available to participate in efficacy trials.

CONCLUSION

Careful preparation of research infrastructures and population cohorts will help ensure the successful conduct of scientifically and ethically sound HIV vaccine efficacy trials in the future.

Seroincidence of HIV-1 infection in African women of reproductive age: a prospective cohort study in Kigali, Rwanda, 1988-1992

OBJECTIVE

To estimate the seroincidence of HIV-1 infection among women of reproductive age in Kigali, Rwanda.

DESIGN

Fixed prospective cohort followed for 36 months between November 1988 and June 1992, as part of an ongoing study of mother-to-child transmission of HIV-1.

SETTING

Centre Hospitalier, Kigali, Rwanda.

SUBJECTS

A total of 216 HIV-seronegative women were enrolled at delivery between November 1988 and June 1989.

METHODS

A blood sample was obtained at delivery to test for HIV antibodies (by enzyme-linked immunosorbent assay and Western blot). Serum was tested every 3 months during follow-up. Incidence density rates of HIV seroconversion were estimated.

RESULTS

The follow-up rate after 3 years was 89%, assessed by the maximum person-years method. The seroincidence density rate was 3.5 per 100 women-years (95% confidence interval, 1.9-5.0). It decreased linearly from 7.6 during the first 6-months postpartum to 2.5 per 100 women-years during the last 6 months of the third year of follow-up. Maternal age did not affect HIV incidence rates. We examined the role of the cohort, counselling, and the first 6-month postpartum effects on this estimate.

CONCLUSION

This fixed cohort provided an overall estimation of the HIV infection incidence rate and its dynamics. These figures could be used for programming future HIV preventive vaccine efficacy trials in Rwanda.

Trimethoprim-sulfamethoxazole versus aerosolized pentamidine for primary prophylaxis of Pneumocystis carinii pneumonia: a prospective, randomized, controlled clinical trial. LFPMI Study Group. Ligue Française de Prévention des Maladies Infectieuses

The objective was to compare the efficacy and tolerance of monthly aerosolized pentamidine versus trimethoprim-sulfamethoxazole (TMP-SMX) to prevent the first episode of Pneumocystis carinii pneumonia (PCP) in human immunodeficiency virus (HIV)-infected patients. In an open, prospective, randomized multicentric clinical trial, HIV-infected patients (n = 214) with CD4 cell counts < 200/mm3 or 20% without a history of PCP or cerebral toxoplasmosis were randomized to receive for at least 2 years aerosolized pentamidine (300 mg monthly) or low-dose daily TMP-SMX (400-80 mg). The mean follow-up was 578 days. The two groups (except for gender) were homogeneous for age, risk group for HIV infection, initial CD4+ lymphocyte count, and mean follow-up. The PCP rate per year of observation using an intent-to-treat analysis was 3.1% and 1.3% in the groups treated with pentamidine and TMP-SMX, respectively (p > 0.05). Moderate or severe clinical and biological side effects were observed in five patients on pentamidine and 33 on TMP-SMX (p < 0.05). Nineteen episodes of cerebral toxoplasmosis were diagnosed during the study. The analysis showed no significant difference in time of development of toxoplasmosis, but only one patient was actually treated with TMP-SMX. Survival was not significantly different in the two groups. Low-dose daily TMP-SMX or monthly aerosolized pentamidine effectively prevented a first episode of PCP in HIV-infected patients, but aerosolized pentamidine was better tolerated. However, TMP-SMX is less costly and should have a preventive effect for toxoplasmosis.

Pyrimethamine plus azithromycin for treatment of acute toxoplasmic encephalitis in patients with AIDS

A prospective study was conducted to evaluate azithromycin in combination with pyrimethamine for treatment of acute Toxoplasma encephalitis in patients with AIDS. Of the 14 patients given 75 mg pyrimethamine and 500 mg azithromycin daily for four weeks, eight were evaluable for clinical response. Five responded favorably, one had an intermediate response and two an unfavorable response. Of the nine patients evaluable for radiological response, six responded favorably, and three had an intermediate response. Eleven adverse events occurred in nine patients: rash (n = 5), abnormal liver function (n = 2), vomiting (n = 3) and hypoacousia (n = 1). This pilot study suggests that the combination of pyrimethamine and azithromycin may be further investigated and that the optimal dosage of azithromycin has yet to be determined.

Urinary trypsin inhibitory activity for the diagnosis of bacterial infection: a prospective study in 690 patients

OBJECTIVES

During the acute phase response, interleukin-1 induces production of inter-alpha-trypsin inhibitor. The measurement of urinary trypsin inhibitory activity which results from the effects of inter-alpha-trypsin inhibitor degradation products is easy, quick and inexpensive. We conducted a prospective study to investigate its value as a diagnostic tool in comparison with C-reactive protein.

METHODS

Comparisons were made in 690 consecutive patients at admission to a department of internal medicine.

RESULTS

The level of urinary trypsin inhibitory activity was significantly higher in patients with bacterial infection (mean = 123 IU/g creatinine) than in patients with either viral infection (34 IU), cancer (50 IU), elevated erythrocyte sedimentation rate without infection (45 IU), miscellaneous non-inflammatory diseases (27 IU) or in non-organic controls (19 IU) (Dunnet's test, p << 0.01). The receiver operating characteristic curve showed that sensitivity and specificity of urinary trypsin inhibitory activity were higher than those of C-Reactive protein for the diagnosis of bacterial infection. For levels > or = 60 IU, sensitivity was 75% and specificity 89%. Urinary trypsin inhibitory activity levels fell within 2 days in patients treated for acute bacterial infection.

CONCLUSION

Urinary trypsin inhibitory activity could be a useful marker of bacterial infection particularly in patients with fever of unknown origin and/or elevated erythrocyte sedimentation rate.