Causes and associations with a low CD4/CD8 ratio
Question:
3/26/2022
A patient was referred to me for a low CD4/CD8 ratio. Her clinical profile is fibromyalgia like. We performed a complete immunologic assessment only her IgA was slightly diminished. HIV screen was negative. Her initial CD4/CD8 ratio was 0.46 and her repeat ratio was 0.66. Both times her absolute CD4 was nl but at the lower limits of normal and her CD8 was normal as well but at the upper limits of normal. Is there anything else you would do or monitor longitudinally over time?
Answer:
McBride and Striker answered this question in PLoS Pathog. 2017 Nov; 13(11): e1006624.
"A low or inverted CD4/CD8 ratio is an immune risk phenotype and is associated with altered immune function, immune senescence, and chronic inflammation in both HIV-infected and uninfected populations [8–11].
The prevalence of an inverted CD4/CD8 ratio increases with age. An inverted ratio is seen in 8% of 20- to 59-year-olds and in 16% of 60- to 94-year-olds [7]. Women across all age groups are less likely to have an inverted ratio than their male counterparts [7]. Age- and hormone-related atrophy of the thymus is theorized to explain the differences between populations. Hormonal influence on the ratio is supported by a correlation between low plasma estradiol levels, high circulating CD8, and low CD4/CD8 ratios in women with premature ovarian failure [12].
In the HIV negative population, a low CD4/CD8 immune risk phenotype reflects immune senescence, is associated with wide-ranging pathology, and may also predict morbidity and mortality [7,15–22].
Despite these associations, it is important to acknowledge that the presence of a low CD4/CD8 ratio is not clearly the cause or the effect of the above pathology. This acknowledgment is further highlighted by the presence of a low ratio in conditions outside the umbrella of traditional organic pathology, including an association between low ratios and pessimists [21]."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5667733/#:~:text=A%20low%20or%20inverted%20CD4,CD8%20ratio%20increases%20with%20age
I hope this information is helpful for you and your patient.
Eric Macy, MD, MS, FAAAAI