Bacterial Infections Pose Major Risks for Drug Abusers
In a recently published review article, scientists say that people who abuse drugs often are vulnerable to bacterial infections, including strains that are resistant to the most powerful antibiotics. Certain antibiotic-resistant bacterial infections have been reported among men who have sex with men who use crystal methamphetamine.
Smoking and inhaling a drug and then expelling the smoke into another person's mouth can transmit bacteria that cause lung diseases. Other infections may be caused by bacteria that normally reside on a person's skin and enter the muscle tissue through injection. Pathogens may be inadvertently mixed with a drug of abuse and travel through a syringe. Also, an association may exist between infections caused by Clostridia, which causes botulism, and black-tar heroin, a form of heroin produced in Mexico.
Infections that may develop include: infective endocarditis, a potentially fatal infection that can damage or destroy the heart valves; pulmonary tuberculosis; wound botulism caused by Clostridia (untreated botulism may progress to paralyze the limbs, trunk, and respiratory muscles, and can result in death due to respiratory failure); necrotizing fasciitis, known as the "flesh-eating disease;" soft tissue infections caused by "skin popping" (injecting under the skin or into the muscle); and skin infections caused by an antibiotic-resistant strain of bacteria.
- WHAT IT MEANS: Infections are among the most serious complications of drug abuse, and people who abuse drugs risk contracting numerous and varied bacterial infections, for which there may be few effective treatments. Although injection drug use is a major path for bacterial infection, drug abusers who do not inject also are at risk. Eliminating drug abuse is the surest way to control the associated infections.
Dr. Rachel Gordon and Dr. Franklin Lowy of Columbia University published their review in the November 3, 2005 issue of the New England Journal of Medicine.
Improving HIV/AIDS Knowledge in Treatment-Seeking Cocaine Abusers
A brief educational intervention can increase HIV/AIDS knowledge among cocaine abusers in outpatient treatment.
Knowledge levels of HIV/AIDS were assessed in 83 adult cocaine abusers in outpatient treatment through completion of the Kelly and Marsch tests (multiple item, true-false tests designed to measure knowledge in three general areas: high-risk sexual and drug practices, risk-reduction steps, and misconceptions about HIV/AIDS). They then were divided into two groups. Members of the experimental group viewed a 12-minute HIV/AIDS education video and met individually with a counselor to review an educational pamphlet on HIV/AIDS. Members of the control group viewed a 10-minute excerpt of a video on the psychopharmacology of cocaine and met individually with a counselor to review a pamphlet on the psychopharmacology of stimulants. Members of both groups again completed the two tests immediately after meeting with the counselors.
The researchers reported that participants in the experimental group had higher test scores following the intervention than participants in the control group. Scores of participants in the control group also increased after crossing over and receiving the same HIV/AIDS intervention.
- WHAT IT MEANS: The results suggest that a brief educational intervention can increase HIV/AIDS knowledge among drug abusers. Although education alone may be insufficient to drive behavior changes, a brief intervention such as this may serve as a component of more extensive interventions.
Dr. Sarah Heil and her colleagues at the University of Vermont published their findings in the August 2005 issue of Experimental and Clinical Psychopharmacology.
Mouse Study Reveals Mechanisms By Which Cocaine Strengthens HIV Infection
Researchers who previously used a mouse model to confirm that cocaine increases the rate at which HIV replicates now have identified pathways and mechanisms responsible for this increase.
Working with genetically engineered mice that have deficient immune systems, Dr. Gayle Baldwin and her colleagues at the David Geffen School of Medicine at UCLA created a practical animal model to study the effects of cocaine on HIV infection.
Based on previous studies suggesting that the immune-suppressing effects of cocaine are mediated through cell-surface proteins called sigma-1 receptors, the UCLA scientists hypothesized that sigma-1 receptors were directly involved in the cocaine/HIV interaction. To test this hypothesis, they treated HIV-positive mice for 10 days with daily injections of saline, cocaine, a sigma-1 blocker called BD1047, or a combination of cocaine and BD1047. Dr. Baldwin and her colleagues observed that the combination of BD1047 and cocaine blocked the impact of cocaine on HIV replication.
- WHAT IT MEANS: The findings suggest that the dynamic interaction between cocaine and HIV, which ultimately results in enhanced HIV replication, is accomplished in part through activation of sigma-1 receptors. Blocking sigma-1 receptors may diminish the effects of cocaine on HIV replication.
The study was published in the December 2005 issue of the Journal of Leukocyte Biology.
Russian Medical System Needs To Adapt to Co-Occurring Drug Abuse, Infectious Diseases
An analysis of co-occurring heroin dependence and infectious diseases in St. Petersburg, Russia and the surrounding area, indicate that drug addiction in this country frequently co-occurs with HIV, hepatitis, and tuberculosis. This presents a serious problem to a medical system that is organized around treating specific diseases, with little focus on treating multiple disorders simultaneously.
Dr. George Woody, of the University of Pennsylvania School of Medicine, and his colleagues at Boston University and St. Petersburg State Pavlov Medical University, examined databases that reflected regional drug dependence, and also assessed personal records of HIV-positive patients from city and regional addiction treatment centers.
The St. Petersburg Addiction Center treated 10,742 patients between 1997 and 2001. In 1997, virtually none of the heroin-dependent patients had HIV; in 2001, this had risen to almost 19 percent. Similarly, the Leningrad Regional Center of Addictions (LRCA) treated 3,162 patients between 1997 and 2003 - the percentage with HIV increased from 0 in 1997 to 40 percent in 2003. In addition, data from the LRCA show that hepatitis C was found in 85 percent of drug-dependent patients in 2003. Evidence of hepatitis B infection was seen in 9 percent of drug-dependent patients and 11 percent of those who were alcohol dependent.
- WHAT IT MEANS: The data show that substance use disorders and infectious diseases constitute parallel and overlapping epidemics in this region. Educational programs aimed at the general public are needed, along with prevention and treatment programs that cross the lines of specific disease boundaries.
The research, which was funded in part by NIDA, was published in the December 2005 issue of European Addiction Research.