HIV Pharmacy Association
HIV patients with renal complications
Guy Baily, consultant physician in HIV and infectious diseases at Barts
and The London NHS Trust, conducted a presentation on the management
of renal complications due to HIV infection.
HIV-associated nephropathy (HIVAN) is caused by collapsing focal segmental
glomerulosclerosis and occurs mainly in African patients with HIV. The
main symptom is proteinurea, sometimes with renal failure.
Dr Baily presented the London HIVAN study, which showed that, within
three years of diagnosis, a third of patients developed chronic end-stage
renal failure. The mainstay of treatment is to start antiretroviral therapy.
In the study, an undetectable viral load was found to correlate with
stabilised or improving renal function.
The risk of renal adverse effects in patients on tenofovir was also discussed.
This is a topical issue since Gilead recently sent all HIV physicians
a reminder letter to highlight the fact that monthly creatinine clearance
and phosphate levels need to be taken during the first year of tenofovir
therapy. Dr Baily said that although pre-licensing studies had not shown
an increased risk of renal dysfunction, post marketing surveillance has
reported Fanconi’s syndrome in 19 patients over two years, and
that this is probably a rare but important side effect of tenofovir.
Dr Baily commented that hypophosphataemia is sometimes seen in patients
on tenofovir. This could be a prelude to the development of Fanconi’s
syndrome, or possibly due to bone demineralisation or yet another phenomenon
of HIV disease. Dr Baily stated that although there are no definitive
links between tenofovir and other renal conditions, tenofovir has not
been adequately studied in patients with pre-existing renal dysfunction
and it should be used with caution in this group.
Rania Betmouni, lead renal pharmacist at Hammersmith Hospital, then gave
an in-depth overview of the management of renal disease. Ms Betmouni
discussed the “modification of diet in renal disease” calculation
for the glomurelular filtration rate. This is increasingly being used
to estimate creatinine clearance, in place of the Cockcroft-Gault equation,
with renal disease being classified over five stages of severity as opposed
to the three current classifications of mild, moderate and severe dysfunction.
This will have an impact on dosing of drugs such as antiretrovirals in
renal impairment in the future.
Finally Reena Popat, renal pharmacist at Barts and The London NHS Trust,
presented two case studies. The first was about a patient with HIVAN
and highlighted that renal HIV pharmacy is not just about adjusting doses
of antiretroviral agents. The patient had suffered from osteodystrophy
and chronic anaemia due to their renal impairment. Both HIV disease and
the drugs used in its treatment may potentially make these conditions
worse and Ms Popat discussed reviewing the HIV treatment to reduce further
renal complications.
The second case focused on renal transplantation in a patient with HIV.
The British HIV Association has recently developed guidelines on this.
Ms Popat discussed the types of patients that would be eligible for a
transplant and the importance of post-transplant immunosuppression regimens
to prevent rejection. Ms Popat discussed how to manage interactions between
antiretrovirals and some
the immunosuppressants such as ciclosporin and prednisolone. The importance
of readjusting antiretroviral doses as renal function improved post-transplant
was also discussed.
Complementary therapies in HIV
Gail Woodland, medicines information pharmacist from the Welsh Medicines
Information Centre, took an in-depth look at the use of different complementary
and alternative medicines (CAM) in HIV and their safety, efficacy and
potential for interactions with drugs.
Studies have shown that over half of patients with HIV will use complementary
therapies and the majority do not disclose this to their clinician. Some
interactions, like the one between St John’s wort and protease
inhibitors, are well documented, whereas others, such as those with echinacea,
are less understood.
Ms Woodland discussed how some complementary therapies might not be suitable
for HIV patients. For example, the use of fish oils at doses greater
than 3g daily may cause immune suppression.
Steve Davis, a nutritional therapist, gave a presentation on his work
as a complementary therapy practitioner for patients with HIV. Mr Davis
discussed how his treatment may be directed towards reducing the side
effects of antiretroviral medicines. He has a more holistic approach
to care.
David Ogden, lead pharmacist HIV services, South West London HIV Network
and Ms Woodland presented a number of case studies. There ensued a lively
discussion about the use of CAM in HIV patients and how best to build
links between the HIV pharmacy team and complementary practitioners.
Rifabutin guidance needs re-evaluation
Hasanin Khachi, rotational pharmacist at Barts and The London NHS Trust,
recently presented at the annual British HIV Association (BHIVA) conference
in March. He gave a reprise of his talk — a study on the pharmacokinetics
of rifabutin and Kaletra (lopinavir/ritonavir) in patients with mycobacterial
disease.
BHIVA guidelines state that when administering the two drugs together, the rifabutin
dose should be reduced to 150mg three times weekly. In their study, the investigators
examined rifabutin and Kaletra levels in five patients. They found that although
Kaletra levels were within therapeutic range, all five patients had subtherapeutic
levels of rifabutin and two patients had experienced a clinical deterioration.
Mr Khachi recommended using rifabutin drug levels to guide dosing on all patients
who are also on protease inhibitors and concluded that current guidance on rifabutin
dosing needs to be re-evaluated.
Online program to improve HIV knowledge
Neal Marshall, HIV pharmacist at the Royal Free Hospital and HIVPA committee
member, presented on “E-HIVe”, an online learning program
in development. It is aimed primarily at pharmacists and technicians
new to the field of HIV who want to improve their knowledge base.
The first four modules — epidemiology, virology, immunology and
disease progression are currently being compiled. Any HIV pharmacists
or technicians who would like to get involved in helping to develop e-HIVe
are invited to contact the HIVPA via its website (www.hivpa.org).
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