Contents
DOCTOR FAX ISSUE 62- Intermittent selection pressure with zidovudine plus zalcitabine treatment reduces the emergence in vivo of zidovudine resistance HIV mutations.
- Lack of Longer-Term Effects of In Utero Exposure to Zidovudine Among Uninfected Children Born to HIV-Infected Women
- Maternal Zidovudine Use Linked to Gestational Age and Birthweight
- Regimens that include protease inhibitors effectively suppress HIV in lymph tissue
- Discontinuation of Prophylaxis for Pneumocystis Carinii Pneumonia in HIV-1-Infected Patients Treated With Highly Active Antiretroviral Therapy
- Prognostic value of JC virus load in cerebrospinal fluid of patients with progressive multifocal leukoencephalopathy.
- M. kansasii disease burden estimated in UK's HIV-positive population
- Older patients at higher risk of AIDS-related distal symmetrical polyneuropathy
- Would Nef-deleted Vaccines be Safe?
- One Third of Gay HIV-infected Men in UK Don't Know their HIV Status
- HIV prevalence in UK is low relative to elsewhere in Europe
- UK urged to implement HIV antenatal screening recommendations
- Cancer and AIDS: A Symbiotic Relationship
- Sustaining the Investment in AIDS Research
|
ANTIRETROVIRALS
|
Intermittent selection pressure with zidovudine plus zalcitabine treatment reduces the emergence in vivo of zidovudine resistance HIV mutations.
Abstract
The development of mutations conferring drug resistance was investigated in 49 antiretroviral-naive asymptomatic HIV-1 subjects with CD4+ cell counts of 250-500/mm3 given intermittent (6-week courses, 6 weeks apart) or continuous treatment with zidovudine (AZT) plus zalcitabine (ddC) over 54 weeks. The concentration of human immunodeficiency virus type 1 RNA in the plasma and the CD4 cell counts were measured every 6 weeks. The rate of decrease of HIV-1 RNA concentration in plasma after a 6-week course of AZT + ddC was similar for each treatment cycle (approximately 1-log reduction). The plasma HIV-1 RNA concentration returned to its initial level at each treatment interruption. The mean CD4 cell counts after 54 weeks in the two treatment groups were similar. Genotype analysis by sequencing the reverse transcriptase coding region from plasma viral RNA on treatment showed a lower frequency of AZT resistance mutations after 54 weeks in patients given intermittent treatment (18%) than in those treated continuously (79 %, P < 0.001). No mutations conferring ddC resistance or multidideoxynucleoside resistance were observed in either group. These findings may have clinical implications for long-term treatment strategies.
Ref: Izopet J, Sailler L, Sandres K, et al. J Med Virol 1999 Feb;57(2):163-8.
Lack of Longer-Term Effects of In Utero Exposure to Zidovudine Among Uninfected Children Born to HIV-Infected Women
Children exposed to zidovudine (ZDV, AZT) in utero and as new-borns and who escaped acquiring HIV from their infected mothers show no cancers or other adverse health effects up through pre-school age, according to a new study from the National Institutes of Health (NIH). It is the first report to assess the late effects of AZT exposure in healthy HIV-uninfected children born to mothers who took the drug to prevent transmitting HIV to their offspring.
The study, sponsored by the Paediatric AIDS Clinical Trials Group (PACTG) and funded by the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institute of Child Health and Human Development (NICHD), appears in the Jan. 13 issue of the Journal of the American Medical Association (JAMA).
"These data are critically important because the current recommendation is to treat HIV-infected pregnant women with regimens that include AZT to prevent perinatal HIV transmission," says NIAID Director Anthony S. Fauci, M.D. "Although these findings are reassuring," he adds, "we need to continue to monitor these children for long-term adverse effects of the drug." The investigators plan to follow these children until at least age 21.
The 234 HIV-uninfected children evaluated in this report are part of PACTG 219, a long-term follow-up study that includes more than 2,200 children who have been enrolled in PACTG prevention and treatment protocols. The 234 children were born to mothers who participated in PACTG 076. This landmark NIH study showed that AZT can reduce HIV transmission from an infected woman to her infant by approximately two-thirds. The children in PACTG 076 were exposed to AZT or a placebo in utero and during labour and delivery, and also as new-borns for six weeks.
The randomised design of PACTG 076 and subsequent follow-up in this study makes it easier to clearly evaluate AZT's potential toxicity, the investigators note. The health of children who received AZT (122 children) can be compared with that of a similar number of children (112) who received a placebo.
For the current study, the investigators evaluated the children at regular intervals. The main measures of interest included physical growth, cognitive and development milestones, immunologic function, cardiac and ophthalmologic evaluations, the occurrence of malignancies, and mortality.
"The good news is that there are no differences in growth and cognitive development between the children exposed to AZT versus the children who were not," comments lead author Mary Culnane, M.S., C.R.N.P, of NIAID's paediatric medicine branch in the Division of AIDS. "It also is reassuring that none of the children have developed cancers or died."
The JAMA article reports on data collected through February 1997. The median age of the children was 4.2 years (range 3.2 to 5.6 years). They continue to be followed in the PACTG clinics.
The authors conclude that their findings complement the earlier findings of PACTG 076, which found no evidence of AZT toxicity in children up to 18 months of age, and are consistent with the limited other early safety data concerning perinatal exposure to AZT. Future evaluations of these and other children in PACTG 219 will help define the long-term safety of AZT use during the perinatal period. Paediatric HIV specialists also hope to establish a registry to track the health of all children exposed to antiretrovirals, a proposal that is being actively discussed within the medical community.
Source: FASTFAX #213, January 22, 1999 published by We The People Living with AIDS/HIV of the Delaware Valley, Inc. [http://www.critpath.org/wtp]
Abstract
Context: With the success of zidovudine chemoprophylaxis for prevention of perinatal transmission of the human immunodeficiency virus (HIV), an increasing number of HIV-exposed but uninfected children will have in utero exposure to zidovudine and other antiretroviral drugs.
Objective: To evaluate the long-term effects of in utero exposure to zidovudine vs placebo among a randomised cohort of uninfected children.
Design: Prospective cohort study based on data collected during Paediatric AIDS Clinical Trials Group Protocol 076, a perinatal zidovudine HIV prevention trial, and Protocol 219, a long-term observational protocol.
Setting: Paediatric research clinics in the United States.
Patients: Two hundred thirty-four uninfected children born to 230 HIV-infected women enrolled in Protocol 076 and followed up through February 28, 1997, in Protocol 219 (122 in the zidovudine group and 112 in the placebo group).
Main Outcome Measures: Physical growth measurements, immunologic parameters, cognitive/developmental function, occurrence of neoplasms, and mortality data assessed every 6 months for children younger than 24 months and yearly thereafter or as clinically indicated. Baseline echocardiogram and funduscopic evaluations were collected before 36 months of age.
Results: Median age of children at time of last follow-up visit was 4.2 years (range, 3.2-5.6 years). There were no significant differences between children exposed to zidovudine and those who received placebo in terms of sequential data on lymphocyte subsets; weight, height, and head circumference z scores; and cognitive/developmental function. No deaths or malignancies occurred. Two children (both exposed to zidovudine) are being followed up for abnormal, unexplained ophthalmic findings. One child exposed to zidovudine had a mild cardiomyopathy on echocardiogram at the age of 48 months; the child is clinically asymptomatic.
Conclusions: No adverse effects were observed in HIV-uninfected children with in utero and neonatal exposure to zidovudine followed up for as long as 5.6 years. Continued prospective evaluations of children born to HIV-infected women who are exposed to antiretroviral or immunotherapeutic agents are critical to assess the long-term safety of interventions that prevent perinatal HIV transmission.
Ref: Culnane, Mary; Fowler, MaryGlenn; Lee, Sophia S et al.; Journal of the American Medical Association (01/13/99) Vol. 281, No. 2, P. 151.
|
No adverse effects were observed in children exposed to zidovudine in utero, but further surveillance of children exposed to antiretroviral or immunotherapeutic medications should be conducted to determine the long-term effects of such measures. |
Maternal Zidovudine Use Linked to Gestational Age and Birthweight
Researchers with the European Collaborative Study have concluded that maternal zidovudine therapy may help reduce the risk of premature birth and low birthweight. Using data from the study, which focused on HIV-infected pregnant women and their children in seven European nations, the researchers found that, among nearly 2,300 mothers who received zidovudine, the risk of premature delivery was decreased by 25 percent and the risk of low birthweight was cut almost in half. Consideration of maternal CD4 cell count and mode of delivery had no major impact on the odds ratios. And the results of "...multivariate analysis suggested that prophylactic zidovudine and prematurity were independently associated with risk of transmission." While the authors did not find a definite causal relationship between zidovudine and lower risk of prematurity, the findings, if confirmed, could be significant for the timing of the commencement of treatment with zidovudine.
Ref: AIDS 1999;13:119-124. Source: CDC HIV/STD/TB Prevention News Update
Regimens that include protease inhibitors effectively suppress HIV in lymph tissue
Combination antiretroviral regimens that include a protease inhibitor appear to be more effective in targeting HIV reservoirs in lymphoid tissue, and in preserving or restoring lymph node architecture than combination regimens containing nucleoside analogues only, according to a report that appears in the January 14th issue of AIDS.
Dr. Jan van Lunzen of the Universitatskrankenhaus Eppendorf in Hamburg, Germany, and a multinational team evaluated axillary lymph node biopsies from 12 patients. They used in situ hybridisation and coculture techniques to detect the presence of HIV.
Following antiretroviral treatment, all the subjects had fewer than 20 copies/mL of plasma HIV RNA for a mean of 25 months. They also had maintained a mean CD4 cell count of 525/µL for at least 10 months. Seven subjects were receiving a protease inhibitor-containing regimen (group I). Four were receiving nucleoside analogue drugs only, and one patient was receiving suboptimal levels of a protease inhibitor (group II).
The results of in situ hybridisation indicated that group II patients had more productively infected CD4+ T cells in lymphoid tissue compared with group I patients, who had "[v]ery low numbers of productively infected lymph node cells." And while the investigators detected no sign of virions on the follicular dendritic cell (FDC) network among the group I subjects, "...large deposits of FDC-bound virions were observed in three out of five patients from group II." In addition, Dr. van Lunzen's group found that lymph node viral cultures in these three patients were positive, "...compared with only one out of seven patients from group I."
Overall, Dr. van Lunzen and associates observed that the protease inhibitor-treated subjects had fewer signs of immunopathological change and a more preserved lymph node architecture compared with the subjects who received nucleoside analogues only.
They point out that it is still not known if these effects are due to a "...particular feature of protease inhibitors or to the potency of the regimen, which may be also achievable with highly potent regimens not containing a protease inhibitor."
Ref: AIDS 1999;13:F1-F8. Source: CDC HIV/STD/TB Prevention News Update
|
OPPORTUNISTIC ILLNESS
|
Discontinuation of Prophylaxis for Pneumocystis Carinii Pneumonia in HIV-1-Infected Patients Treated With Highly Active Antiretroviral Therapy
Researchers from the University Hospital Utrecht and Utrecht University in the Netherlands report that Pneumocystis carinii pneumonia (PCP) prophylaxis can be safely stopped in HIV-1 infected patients on highly active antiretroviral therapy (HAART) who have CD4 cell counts greater than 200 cells per microliter. The researchers, led by Margriet M. E. Schneider, investigated the cessation of PCP prophylaxis in 78 patients on HAART with CD4 cell counts greater than 200 cells per microliter. After a mean follow-up of 12.7 months, none of the patients developed PCP. The authors suggest additional studies that include more patients, an immunological substudy, and longer follow-up to determine treatment recommendations.
Ref: Schneider, Margriet M.E.; Borleffs, Jan C.C.; Stolk, Ronald P. et al. Lancet (16/01/99) Vol. 353, No. 9148, P. 201. Source: CDC HIV/STD/TB Prevention News Update
Prognostic value of JC virus load in cerebrospinal fluid of patients with progressive multifocal leukoencephalopathy.
JC virus (JCV) load was determined by using quantitative polymerase chain reaction in cerebrospinal fluid (CSF) of 12 patients with AIDS-associated progressive multifocal leukoencephalopathy (PML) and compared with clinical outcome. JCV loads varied widely (3-7 log10 JCV equivalents/mL of CSF) and were apparently not related to absolute CD4 cell counts or CSF and plasma human immunodeficiency virus type 1 loads. A significant correlation was observed between JCV load and survival time (Spearman's rank correlation, -0.83; P<. 01). Moreover, CSF JCV load decreased and then became undetectable in 1 PML patient receiving cidofovir treatment, and this was associated with clinical improvement. These results show that CSF JCV load may be useful as a prognostic parameter and in monitoring the effectiveness of anti-JCV therapies in PML patients.
Ref: Taoufik Y, Gasnault J, Karaterki A, Pierre Ferey M, Marchadier E, Goujard C, Lannuzel A, Delfraissy JF, Dussaix E. J Infect Dis 1998 Dec;178(6):1816-20
M. kansasii disease burden estimated in UK's HIV-positive population
Investigators from London report that the incidence of HIV-related Mycobacterium kansasii infection in the UK is similar to that reported in high prevalence areas in the US.
They also note that "...frequent isolation of M. kansasii from the stool suggests that the gastrointestinal tract may be a significant source of disseminated infection."
M. kansasii infection is known to be endemic in the UK, but the disease burden and characteristics of this infection in HIV-positive individuals are not well established, Dr. J. L. Klein of St. Thomas' Hospital and colleagues explain.
To further investigate this, Dr. Klein's group conducted a retrospective review of M. kansasii infections reported at two London HIV Units. Their findings on 26 patients appear in the November issue of the Journal of Infection.
Nine patients had pulmonary disease and 10 had disseminated M. kansasii infection. Dr. Klein and others identified M. kansasii in colonies in the respiratory or gastrointestinal tracts of the remaining seven patients. In addition, they were able to isolate M. kansasii from the stool of 9 of the 26 patients.
"Disseminated M. kansasii infection occurred in 0.44% of AIDS cases seen in our two units and all isolates were resistant to isoniazid in vitro," they report. Of the 13 subjects who received antimycobacterial therapy, 11 achieved a clinical response. The four patients who relapsed had all received suboptimal therapy.
"In our study," the UK team said, "...the symptoms reported by patients with M. kansasii infection were nonspecific, and thus often difficult to distinguish from those of symptomatic HIV infection."
According to Dr. Klein's group, this is the first UK study to "...demonstrate rates of M. kansasii infection in the HIV-seropositive population comparable to those reported from highly endemic areas of the US."
Ref: J Infect 1998;37:252-259. Source: CDC HIV/STD/TB Prevention News Update
Older patients at higher risk of AIDS-related distal symmetrical polyneuropathy
Several factors appear to contribute to the development of AIDS-related distal symmetrical polyneuropathy (DSP), according to New York City researchers. These include older age, greater immunosuppression, poor nutritional status and the presence of chronic disease.
Peripheral neuropathy is one of the most common HIV-related neuropathies, and DSP is the type most frequently seen in AIDS patients, Dr. Michele Tagliati and colleagues at the Mount Sinai Medical Center explain.
However, "[t]he cause of DSP in AIDS is unknown," they report in the January issue of the Archives of Neurology. To further investigate the factors associated with this condition, Dr. Tagliati's group evaluated 251 consecutive patients seen for neurologic complications of HIV infection.
Thirty-eight percent were diagnosed with DSP, which was most commonly characterised by "...nonpainful paraesthesia (71%), abnormalities of pain and temperature perception (71%), and reduced or absent ankle reflexes (66%)." The researchers also noted that the DSP patients were "significantly older" than those without DSP and had lower CD4 cell counts and haemoglobin levels. These features, along with abnormal serum albumin levels and weight loss, also correlated with poor scores on nerve conduction studies, regardless of whether or not DSP was diagnosed.
Overall, Dr. Tagliati's group concludes that the "...combination of age, immunosuppression, markers of chronic disease, and nutritional deficiency effects provide a substantial contribution to the development of DSP and electrophysiologic abnormalities in patients with AIDS."
They believe that additional studies are needed to establish the pathogenesis of AIDS-related DSP, as well as possible therapeutic strategies, such as the use of nutritional support and treatment with nerve growth factor and cytokine antagonists.
Source: CDC HIV/STD/TB Prevention News Update Abstract Objective: To determine the effects of immunodeficiency, nutritional status, and concurrent systemic disease on peripheral nerve function in acquired immunodeficiency syndrome.
Design: Survey of subjects infected with human immunodeficiency virus (HIV), recruited as part of a prospective study of neuromuscular complications of HIV infection.
Setting: A neuro-acquired immunodeficiency syndrome outpatient clinic in a university medical centre.
Patients: A consecutive sample of 251 HIV-infected individuals. Primary care providers referred subjects to the study for evaluation of neurologic symptoms or for prospective neurologic assessment.
Main Outcome Measures: Standardised history and neurologic examination, laboratory tests (complete blood cell count, serum albumin level, vitamin B12 level, and T-lymphocyte subsets), and electrophysiologic testing of sural, tibial, and ulnar nerves.
Results: The most frequent neurologic diagnosis was distal symmetrical polyneuropathy (DSP) (38%). The most common clinical features were nonpainful paraesthesias (71%), abnormalities of pain and temperature perception (71%), and reduced or absent ankle reflexes (66%). Patients with DSP were significantly older (P=.009), and had lower CD4 lymphocyte cell counts (P=.004) and lower haemoglobin levels (P=.004) than those without DSP. Deterioration of values on nerve conduction studies, irrespective of the clinical diagnosis of DSP, was significantly correlated with low CD4 counts, ageing, abnormal serum albumin and haemoglobin levels, and weight loss. Most of these factors co-correlated, and, with the exception of age, no single variable significantly accounted for changes in results of nerve conduction studies when the influence of other factors was eliminated.
Conclusion: The combination of several factors, including age, immunosuppression, nutritional status, and chronic disease, contributes to distal peripheral nerve dysfunction in HIV infection.
Ref: Michele Tagliati, MD; Juliet Grinnell, BA. Et al. Arch Neurol 1999;56:84-89.
|
OTHER NEWS
|
Would Nef-deleted Vaccines be Safe?
HIV is composed of many genes, one of which is called nef. Researchers have noted that some people infected with HIV who remain symptom-free are infected with strains of the virus that are missing the nef gene. In 1995, researchers in the USA reported the case of a long-term non-progressor with relatively high CD4+ counts and low viral load. Analysis of the man's HIV revealed that the virus's nef genes were defective.
Researchers in Australia have also reported the absence of the nef gene in a group of HIV non-progressors. These reports suggest a link between nef and HIV progression. Indeed, studies involving monkeys infected with SIV have shown that nef plays a crucial role in the development of AIDS. This has given rise to the hope that an HIV strain missing nef might be used to create an anti-HIV vaccine (despite many attempts, vaccine designers have not yet been able to create a product that protects anyone from HIV).
However, in a recent letter to the New England Journal of Medicine, that hope suffered a serious blow. In the letter, American researchers report on the long-term follow-up of a subject whose HIV was missing the nef gene. This subject had previously been classified as a long-term non-progressor. Recently, however, his CD4+ count declined to almost 200 cells, while his viral load remained below 50 copies. Interestingly, the man's CD8+ count remained high, indicating that viral replication was quite active. Despite the use of two nucleoside analogues and nevirapine, the man's CD8+ cell count continued to increase, thereby raising questions about the ability of this therapy to fully suppress viral activity.
This case, among others, of disease progression despite missing or damaged nef genes raises questions about the effectiveness of a "nef-deleted" vaccine.
Indeed, these results remind scientists about the pitfalls of designing vaccines without a clear understanding of why some people are able to withstand HIV without developing disease.
Ref: New England Journal of Medicine 1999;340(3):236-237. Source: CATIE News.
|
The authors comment that..."various hypotheses could explain this disease progression. It is possible that viral replication (albeit at levels that cannot be detected by current plasma viral-RNA assays) is sufficient to cause the loss of CD4 T cells through a direct virus-induced cytopathic effect, strong cellular immune responses to virus-infected cells, or indirect mechanisms. It is also possible that thymic regenerative capacity has declined to a point at which the production of CD4 T cells cannot match the destruction." The nef deletions observed in March 1998 were similar to those in samples obtained from the patient in 1997, 1994, and 1993. A separate publication reported on cytotoxic T-cell responses to HIV in subjects with nef-deleted HIV-infection ("Strong human immunodeficiency virus (HIV)-specific cytotoxic T-lymphocyte activity in Sydney blood bank cohort patients infected with nef-defective HIV type 1" Dyer WB, Ogg GS et al. J Virol 1999 Jan;73(1):436-43.). Proposals for the use of live attenuated human immunodeficiency virus (HIV) type 1 (HIV-1) as a vaccine candidate in humans have been based on the protection afforded by attenuated simian immunodeficiency virus in the macaque model. Although it is not yet known if this strategy could succeed in humans, a study of the Sydney Blood Bank Cohort (SBBC), infected with an attenuated HIV-1 quasispecies with natural nef and nef/long terminal repeat deletions for up to 17 years, could provide insights into the long-term immunological consequences of living with an attenuated HIV-1 infection. In this study, HIV-specific cytoxic T-lymphocyte (CTL) responses in an SBBC donor and six recipients were examined over a 3-year period with enzyme-linked immunospot, tetrameric complex binding, direct CTL lysis, and CTL precursor level techniques. Strong HIV-specific CTL responses were detected in four of seven patients, including one patient with an undetectable viral load. Two of seven patients had weak CTL responses, and in one recipient, no HIV-specific CTLs were detected. High levels of circulating effector and memory HIV-specific CTLs can be maintained for prolonged periods in these patients despite very low viral loads. |
One Third of Gay HIV-infected Men in UK Don't Know their HIV Status
New statistics from Britain's Public Health Laboratory Service show that one-third of the HIV-infected homosexual men in the country are unaware of their HIV status. The data, which are derived from studies intended to determine how many HIV-infected individuals are in different communities, emphasise the risk of unprotected sex, noted the Terrence Higgins Trusts' Colin Dixon. Furthermore, whereas about 90 percent of homosexual men in the United States and other European nations have been tested for HIV, only about 55 percent in Britain have. In Britain, almost 32,000 individuals have been diagnosed with HIV since the early 1980s.
Source: CDC HIV/STD/TB Prevention News Update
HIV prevalence in UK is low relative to elsewhere in Europe
Britain has a relatively low prevalence of HIV infection compared with other west European countries, but transmission is continuing, especially among homosexual and bisexual men, according to public health officials.
In its latest report on HIV prevalence, the Public Health Laboratory Service says that around 40% of HIV infections among homosexuals and bisexuals attending specialist genitourinary clinics remain undiagnosed. The figure for undiagnosed infections among heterosexuals is more than 50%. "This shows the need for continuing health promotion and offering HIV testing as a routine part of GU (genitourinary) medicine care everywhere," public health officials write.
The latest estimates of prevalence are based on an unlinked anonymous HIV survey using blood samples from people attending specialist genitourinary clinics in England and Wales. The data cover the period from 1990 to 1997.
The officials report that HIV prevalence remains higher in London than elsewhere in the country. Prevalence among homosexual or bisexual men attending the specialist clinics in London is estimated to be about 1 in 11. Outside London, prevalence is about 1 in 26. Prevalence among injecting drug users in London is about 1 in 25 for men and 1 in 66 for women. Outside London, the prevalence drops to 1 in 268 for men and 1 in 245 for women.
Prevalence among heterosexuals attending the clinics in London is estimated at about 1 in 125 among men and 1 in 142 among women. Outside London, the prevalence is 1 in 801 for men and 1 in 978 for women.
The prevalence of HIV among women giving birth in London is estimated at 1 in 533 and the percentage of undiagnosed infections is about 70%. "This is of particular concern as it was not therefore possible to offer these women either interventions, which would have decreased the risk of their child becoming infected, or treatment for themselves," the authors say.
Overall, 1 out of every 1,000 UK residents between the ages of 15 and 49 years is estimated to be infected with HIV. This is low by European standards, the authors say. In Western Europe, only Germany, Sweden, Norway and Finland have lower prevalence rates.
"The relatively low prevalence of HIV in the UK is likely to be associated with targeted interventions among behaviourally vulnerable groups, the early introduction of public education campaigns in the mid-1980s, the availability of free and open access GUM (genitourinary medicine) clinics and needle exchange schemes," the authors say.
Source: CDC HIV/STD/TB Prevention News Update
UK urged to implement HIV antenatal screening recommendations
Britain risks falling further behind France and the US in detecting HIV-infected mothers unless clinicians move quickly to implement new antenatal screening recommendations for high HIV prevalence areas, such as London, according to a British public health official.
Dr. Angus Nicoll of the Public Health Laboratory Service writes that a new group, with African representation, has been set up in London to ensure that women in the city receive an HIV test as a routine part of antenatal care. The new screening initiative follows the publication of a report in April 1998 in which representatives of government and the medical royal colleges recommend making routine testing available in high prevalence areas.
"Antenatal care in London has until the year 2000 (when the intercollegiate group reconvenes) to start doing as well as colleagues do in Paris and New York," Dr. Nicoll writes. His comments appear in an editorial in the quarterly Journal of Medical Screening. Routine antenatal HIV testing has been recommended for pregnant women in London since 1992, but practice has lagged behind policy because of the ambivalent attitude of clinicians, Dr. Nicoll writes. "In the 1980s many people felt that HIV positive people would not wish to know their status, and testing should only follow lengthy specialist counselling," he says.
"This established a legacy of exceptionalism and mystification around HIV testing, which persists, particularly, in antenatal care," he comments. As a consequence, fewer than 30% of HIV-positive mothers were diagnosed before delivering a child in 1997. Adjusting this figure for previously diagnosed infection, the diagnostic rate was 13%, he says.
In light of the failure of the earlier policy, an intercollegiate group convened and drew up fresh recommendations last April. Besides urging that screening be made available for all women in high prevalence areas, it urges clinicians to counsel mothers found to be HIV positive.
For areas of low HIV prevalence, the report recommends selective screening with special care for women at high risk. "The challenge is now to those providing antenatal care to implement these recommendations," Nicoll writes.
Ref: J Med Screening 1998;5:170-171. Source: CDC HIV/STD/TB Prevention News Update
Cancer and AIDS: A Symbiotic Relationship
AIDS and cancer research discoveries are often beneficial to both fields. The two fields are intertwined; HIV infection has resulted in an increase in the number of cancer patients, with an estimated one-third of people with AIDS acquiring cancer. Some malignancies have become associated with HIV infection, such as Kaposi's sarcoma, lymphoma, and anal and genital cancers. While it does not directly cause cancer, HIV can influence the development of the disease, with infection leading to increases in cytokines and growth factors. Dr. Robert Gallo, of the Institute of Human Virology at the University of Maryland and head of the tumor biology program at Baltimore Cancer Center, said that "we will probably learn more from HIV about indirect mechanisms that influence cancer than we have ... ever learned from combined research in all medical research history." AIDS advocacy groups have also provided a model for cancer advocates to follow for both fundraising and education programs.
Ref: Scientist (01/18/99) Vol. 13, No. 2, P. 1; Rayl, A.J.S. Source: CDC HIV/STD/TB Prevention News Update
Sustaining the Investment in AIDS Research
In an opinion piece in the Scientist, Neal Nathanson, the director of the Office of AIDS Research at the National Institutes of Health, outlines the reasons for disproportionate funding for HIV/AIDS research, explaining why the continuation of investment in research is vital for the future. Nathanson first states that, while the AIDS death rate has declined in the United States, HIV incidence remains stable and is increasing in some sub-populations. Worldwide, new HIV epidemics are emerging. According to Nathanson, HIV/AIDS research needs sustained funding because it is transmissible. A breakdown in the fight against HIV could lead to an outbreak of infections. Diseases like cancer and heart disease, which may not receive as much funding per individual affected, are not infectious. The research done for HIV/AIDS has also led to treatments for other diseases and other discoveries. Still, HIV drugs have not eliminated viral replication in the hosts, and more research needs to be done on the long-term effects, the development of drug resistance, adherence issues, and differential access to the drugs. Prevention efforts must be maintained and fostered. Heterosexual transmission has become the chief route of HIV infection in most of the world, and drug users and their partners are the quickest growing segment of AIDS cases in many countries, including the United States. The development of an HIV vaccine is of the utmost priority, Nathanson concludes, and the process will be exceedingly difficult.
Ref: Scientist (01/04/99) Vol. 13, No. 1, P. 9; Nathanson, Neal. Source: CDC HIV/STD/TB Prevention News Update
|
The next issue of AIDS Treatment Projects "Doctor Fax" due for distribution on 12th February will be reporting from the 6th Conference on Retroviruses and Opportunistic Infections, Chicago, 1st - 5th February. Next Morning Summaries from the 6th Conference on Retroviruses and Opportunistic Infections -- will be available to users of Medscape (formerly Healthcare Communications) at: http://hiv.medscape.com/hiv/
|
ATP DR FAX SYMPOSIUM II NEW HIV TREATMENTS: IMPLICATIONS FOR CLINICAL PRACTICE A One Day Symposium
DATE: Thursday 25 February 1999
VENUE: Royal College of Physicians, London
CO-CHAIRS: Stefano Vella, Istituto Superiore di Sanita-Roma, Rome Italy
Anton Pozniak, Chelsea & Westminster Hospital, London, UK
INVITED SPEAKERS INCLUDE: Dominique Costagliola (France), Heather Leake (UK), Marty Markowitz (USA), Francis Rotblatt (UK) Programme will include discussion of new treatments: FTC, MKC-442, ABT-378, new capsule ritonavir, efavirenz, 3 newer NNRTI's, abacavir, amprenavir, enteric coated ddI, adefovir, T-20, tipranavir, F-ddA.
PLACES STRICTLY LIMITED: