SONIC

Human immunodeficiency virus (HIV) is a virus that attacks the body’s immune system, particularly the dendritic and CD4 T-helper cells, which are important subsets of immune cells that help fight infection. It is transmitted via bodily fluids (e.g., sexual intercourse, breastfeeding, intravenous drug use) and risk factors include residence in West Africa, homosexual/bisexual biologically male individuals, intravenous drug use, hemophilia, blood transfusion recipients, and maternal HIV infection. Measurement of CD4 cell counts and HIV viral load are often measured to monitor disease progression. If HIV is left untreated, it can progress to AIDS, which occurs when the CD4 cell count reaches below 200 cells/microL. Individuals with AIDS are highly susceptible to opportunistic infections (i.e., infections that occur more often or are most severe in people with weakened immune systems), like cytomegalovirus (CMV).  

Since HIV/AIDS is a chronic disease, most people with HIV/AIDS will require long-term treatment with multiple medications, known as antiretroviral therapy (ART). These medications can often cause a variety of adverse effects. 

The “O” in SONIC stands for organ toxicity. Some of the ART classes are known to cause organ toxicity, particularly in the kidneys, liver, and heart. For example, tenofovir disoproxil fumarate (TDF) is an NRTI often used and causes renal toxicity. This risk is increased in individuals with a history of chronic kidney disease. TDF causes nephrotoxicity by damaging the proximal tubules of the kidneys, which causes the wasting of electrolytes and proteins to the urine. Tenofovir alafenamide (TAF) is another NRTI that contains the same active ingredient as TDF but is considered less toxic to the kidneys as its administration leads to lower drug plasma levels in the body. This means less exposure of the active drug to the kidneys. 

Another concern is hepatotoxicity, which is an adverse effect associated with certain NNRTIs like nevirapine and efavirenz, and protease inhibitors like darunavir and atazanavir. Monitoring of liver enzymes can be helpful in evaluating for these side effects. Moreover, pancreatitis has been reported with lamivudine. Serum amylase and lipase can be used to evaluate for pancreatitis. 
 
Finally, cardiovascular problems (e.g., cardiomyopathy, arrhythmia) have been associated with several ART medications. Didanosine is an NRTI that has been linked to myocarditis (i.e., inflammation of the myocardium) and zidovudine has been shown to cause cardiotoxicity due to mitochondrial dysfunction in cardiac cells. These HIV drugs should be avoided if individuals present with new-onset signs and symptoms of heart failure or cardiomyopathy (e.g., shortness of breath, tachycardia, arrhythmia). An echocardiogram (ECHO) can help evaluate the structural and functional integrity of the heart chambers.