Comparing Viruses -- HIV and Hepatitis C in Mostly Men

In high-income countries today, HIV is most commonly transmitted in the following ways:

• unprotected sex
• sharing equipment for substance use

Hepatitis C virus (HCV) is also transmitted in similar ways, particularly among HIV positive men. Co-infection with both of these viruses can affect the immune system and liver. Researchers have wondered what impact co-infection might have on the kidneys. To find out more about this issue, doctors in France conducted a study. Their findings suggest that HCV co-infection can make kidney health worse.

Study Details

In the span of nine years 100 people underwent a kidney biopsy because of various complaints at the Pitie-Salpetriere Hospital in Paris. Researchers there reviewed the health records of these people and were able to perform an analysis of their kidney health based on their viral infection history.

The average profile of participants when they first sought medical care was as follows:

• 33% female, 67% male
• age -- 50 years
• 55% of participants were White and no further ethno-racial information was available
• 50% of participants had high blood pressure
• most patients had chronic kidney disease, with an average eGFR of 51

Participants were divided into the following three groups:

• HIV positive -- 40 people
• HCV positive -- 30 people
• both infections -- 30 people

Results

Biopsies of the kidneys revealed that some participants had kidney inflammation, particularly the parts of the kidney that filter blood. Inflammation of this part of the kidney is called MPGN(membranorproliferative glomerulonephritis).

MPGN can occur because antibodies get deposited in the membranes of the filtering units of the kidney -- the glomerulus. These membranes help to filter wastes out of the blood into the urine. MPGN can happen in some cases of chronic viral infections. The proportion of people with MPGN in each of the three groups was as follows:

• HIV positive -- 34%
• HCV positive -- 9%
• both infections -- 57%

Biopsies revealed that the blood vessels in the kidneys of some of the people with HIV monoinfection were prematurely stiffened, suggesting cardiovascular disease.

When the kidneys are severely injured, wastes can build up in the body. To help remove waste materials artificial filtration of the blood can be done. This is called dialysis. Only a small number of people needed this procedure, as follows:

• HIV positive -- 6 people
• HCV positive -- 6 people
• both infections -- 5 people

Not all people co-infected with HCV and HIV received treatment for these infections in the French study. However, those co-infected people who were treated had their kidney health improve.

Deaths

Twenty-one people in this study subsequently died, most of whom had either HCV or HCV and HIV. Participants who had MPGN and HCV infection were at heightened risk of death. Other factors that played a role in contributing to the death of HCV-HIV co-infected people were as follows:

• delays in getting a kidney biopsy
• being relatively young
• having a diagnosis of MPGN

Aces

Medicines called ACE-inhibitors (angiotensinconverting enzyme) are used to reduce blood pressure and were commonly prescribed to participants along with lipid-lowering medications called statins. Neither group of drugs seemed to have any negative impact on participants' survival.

The factors statistically linked to death (in general) in this study were as follows:

• HCV-HIV co-infection
• having water retention

This latter problem occurs when the kidneys are not able to flush water out of the body.

The findings from this study highlight the kidneydamaging potential of HCV infection and the need to help HCV positive people engage in and access the care that they need. The French study was done with a group made up mostly of males. Our next report focuses on co-infected women and the impact HCV might have on their kidney health.

Reference

1. Izzedine H, Sene D, Cacoub P, et al. Kidney diseases in HIV/HCV-co-infected patients. AIDS. 2009 Jun 19;23(10): 1219-26.

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