Compiled by Gus Cairns
HIV blamed for peripheral neuropathy
The painful and sometimes crippling condition, peripheral neuropathy, is largely
caused by HIV itself, not drugs used to treat it, study investigators have
concluded.
Researchers found certain drugs appeared to increase the chance of neuropathy
developing in the first year of treatment. But after that, with the exception
of d4T, HIV drugs appeared to protect against neuropathy.
The HOPS cohort of 7,000 patients in seven US cities has been used for different
HIV studies since 1992. This study looked at neuropathy in a subgroup of 4,400
patients.
It found new cases of neuropathy peaked at 25 cases per 100 patients a year
in 1995, before falling to five cases a year in 2002.
The strongest single predictor of whether people developed neuropathy was
having a lowest-ever CD4 count (a 'CD4 nadir') below 200, and especially below
50.
Other predictors were having a pre-treatment viral load above 10,000, being
over 40, being Caucasian, or having diabetes.
Drugs that seemed to bring on, or worsen, neuropathy during the first year
of therapy included d4T, ddI, indinavir, ritonavir, saquinavir and nevirapine
- a mixed bag of all three commonly-used classes.
Researchers suggest that people who develop neuropathy on HIV treatment have
been “predisposed to it because of injury to nerve tissue” caused
by HIV.
Meanwhile, another study has found that one of the few effective treatments
for neuropathy is the supplement acetyl L-carnitine (ALC).
When ALC was used to treat neuropathy in people with diabetes, it promoted
nerve re-growth and reduced pain. It took a year for the full effects to become
apparent, though some patients reported pain relief after six months.
Syphilis surge may wane naturally
A recent surge in syphilis cases largely among gay men in the US may be more
to do with the natural cycle of the disease than an increase in unsafe sex,
a study suggests.
And the recent steep increase in syphilis may start to die back as people
already infected become immune.
Researchers in London spotted a 10-year cycle in US syphilis figures suggesting
the recent outbreak may be due to this community having no acquired immunity
to the sexually transmitted infection in the 1990s.
Although people can catch syphilis more than once, they develop a degree of
lifelong immunity to the disease.
Epidemiologist Dr Nicholas Grassly and his team at Imperial College, London,
analysed the syphilis data from 68 American cities between 1941 and 2002.
They noticed that rises and falls in syphilis followed a regular eight- to
11-year cycle, unlike gonorrhoea which seemed to more closely mirror increases
and decreases in unprotected sex.
Gonorrhoea in the UK peaked when soldiers returned from World War Two and
again in the swinging sixties and seventies. Immunity to gonorrhoea is not
acquired and it can be caught repeatedly.
Grassly accepts that an increase in unsafe sex in the late 90s may have sparked
the recent syphilis outbreaks. But the increases were much more dramatic than
those found with other STIs.
Annual diagnoses increased 12-fold among men between 1995 and 2003 in the
UK and 21-fold (2100 per cent) among gay men. 
By contrast, gonorrhoea figures increased 75 per cent among gay men during
the same period, and HIV by about 35 per cent.
Grassly said: “It is striking how repeated epidemics of syphilis are
predicted by what we know about the natural history of infection. Troughs
in the number of cases offer an unprecedented opportunity for eradication
of the disease. However, when this opportunity is missed, an epidemic is likely
to follow.”
Syphilis is still a serious infection, although usually treatable by antibiotics.
Researchers from Dublin told the 7th Glasgow Aids Conference last November
that up to 25 per cent of HIV positive patients failed first-line syphilis
treatment, in contrast to 10 per cent of HIV negative patients.
Needle-free T-20 may be here soon
A needle-free system for injecting the drug T-20 (Fuzeon) may be here
soon. The Biojector 2000 device, which uses compressed carbon dioxide to fire
a thin stream of liquid directly through the skin, achieved equivalent blood
levels of T-20 in patients as those who used the standard needle.
A needle-free delivery system for T-20 might significantly increase its use,
as fear of injecting can be a barrier to prescribing.
Hard lumps under the skin called injection site reactions, which last for
more than a week in a quarter of cases, has also limited the number of people
using T-20.
Fuzeon distributors Roche are exploring plans to evaluate using the needle-free
system for T-20.
Tenofovir may worsen kidney problems
When the nucleotide analogue tenofovir (Viread) was developed, researchers
at its parent company Gilead paid particular attention to the state of patients'
kidneys.
This was because licensing for HIV treatment of a very similar drug, adefovir,
was stopped due to unacceptable kidney damage.
Since then most studies have found no more kidney problems in patients on
tenofovir.
However, case reports of individual patients who get kidney damage while taking
tenofovir continue to surface.
Now German scientists have discovered that the drug produces a very mild degree
of kidney malfunction, which could make problems worse in patients with pre-existing
kidney disease.
Researchers found that the kidneys of patients taking tenofovir filtered the
blood less efficiently, and that they had a third more protein in their urine
(a sign of inefficient kidneys) than patients not taking the drug.
They emphasised that kidney function in most patients on tenofovir was still
within normal limits.
In a separate study, Dr Lynda Szczech, of Duke Hill University, in the US,
estimated that around seven per cent of a group of Afro-Americans with HIV
not on treatment had detectable kidney damage. These are the patients for
whom doctors might think twice about before prescribing tenofovir.
Caesareans reduce mother-to-child infection
Risk of mother-to-child HIV transmission could be almost halved by using universal
elective Caesarean section, even in mothers taking anti-HIV drugs with an
undetectable viral load, a new study shows.
The number of babies currently infected with HIV through 'vertical transmission'
has now fallen under one per cent in the UK, largely due to improvement in
care and suppression of HIV during pregnancy and labour with HAART.
But study investigators estimate that using Caesareans universally could further
cut that rate by 40 per cent.
The study of babies born to HIV positive mothers in Western Europe between
1997 and May 2004, found that the mother-to-baby HIV transmission rate fell
from five per cent in 1997/8 to one per cent in 2001/2.
Taking HIV drugs during pregnancy was overwhelmingly the best way to protect
the baby. The transmission rate among women who did not take HIV mediation
was 11.5 per cent.
Over the whole study period, seven per cent of babies delivered vaginally
were infected compared with two per cent delivered by elective Caesarean and
three per cent by emergency Caesarean.
Only 11 babies out of 1,183 were infected with HIV by mothers taking HIV drugs.
Less than half (five) were delivered by Caesarean even though two-thirds of
deliveries were by Caesarean.
All but one of the infections occurred in women who started taking drugs late
in pregnancy rather than throughout.
Recently there has been debate about whether pregnancy guidelines still need
to recommend Caesareans. The current BHIVA guidelines state: “Although
a Caesarean section is the recommended mode of delivery for women with HIV,
some women may still wish for a vaginal delivery.
“This may be an important consideration for women who are planning to
return to a country where subsequent Caesarean section deliveries may not
be possible or safe.”
medical notes
The Pill may make you more infectious
Oral contraceptives may make women with HIV more infectious, and could make
HIV negative women more vulnerable to infection, researchers have found. Women
taking the oestrogen/progesterone pill had more of a molecule called CCR5
on the surface of the CD4 cells in their vagina. CCR5 is one of the two molecules
that the most commonly-transmitted type of HIV must latch on to infect a cell.
Dr Kapembwa, of Imperial College, London, said: “There is evidence from
previous studies showing that women using combined oral contraceptives may
shed more HIV from their cervix than non-users.”
Flu drugs recommended for HIV positive people
People with HIV who have been in contact with people with influenza should
take an anti-flu drug, especially if they have not been vaccinated this winter,
the Department of Health (DH) has said. The DH announced that the amount of
influenza A circulating this winter was now above the threshold level which
triggered access to the prescription flu drug Relenza (zanamivir) or Tamiflu
(oseltamivir) -
especially in the north of England. People with lowered immunity with no flu
jab, or where their jab did not match the type of flu circulating, should
take either to prevent infection.
Scientists discover protective monkey protein
Scientists have found that monkeys have protective protein called Trim-5 alpha
which prevents them from catching HIV.
The discovery opens up exciting new prospects for anti-HIV drugs and possible
gene therapy against HIV. Another group of scientists have created T-cells
immune to HIV by using a much-hyped hi-tech gene therapy called RNA interference
to stop them expressing
receptors on their surface
that HIV links to.
Diabetes dementia risk
People with HIV and diabetes are nearly six times more
likely to develop dementia, according to a study from Hawaii. Researchers
found that one in six HIV positive people over 50 had diabetes compared with
only one in 100 in under-50s. People with
diabetes were 5.7 times more likely to develop HIV-associated dementia independent
of other risk
factors like smoking and high blood pressure. Previous studies have found
that men taking HIV drugs
are over five times more likely to get diabetes than the general population.
Meanwhile, US scientists
have found that smoking, diabetes, high blood pressure and high cholesterol
each independently increased
the risk of dementia in middle-aged HIV negative people by 40 per cent, and
by 230 per cent if all four were present.
Increase in hep C medical accidents
The Health Protection Agency reports that nine medical workers in the UK were
infected with hepatitis C following needlestick
accidents or similar exposure between July 1996 and June 2004, compared with
just one HIV infection. Hep C infection in these situations is getting more
common, with six of the nine cases reported since July 2003 and three in the
first three months of 2004. Seven of the nine cases occurred
in hospital settings.
Last month we stated that hypersensitivity to abacavir can occur in up to
18 per cent of people treated with the drug. This rate was found in one study
of 50 patients treated with abacavir during primary (the first few weeks of)
HIV infection. During chronic infection (once the virus established in the
body) the rate of hypersensitivity to the drug commonly found is around five per cent.
