Thursday, September 6, 2012

Quantifiable Lymphocytic reactivity to metals can develop in 1-4 years after MOM hip revisions in asymptomatic patients


2012 Aug 31. doi: 10.1002/jor.22214. [Epub ahead of print]

Asymptomatic prospective and retrospective cohorts with metal-on-metal hip arthroplasty indicate acquired lymphocyte reactivity varies with metal ion levels on a group basis.

Source

Department of Orthopedic Surgery, Rush University Medical Center, 1735 W Harrison MC107, Chicago, Illinois 60612. nhallab@rush.edu.

Abstract

Some tissues from metal-on-metal (MoM) hip arthroplasty revisions have shown evidence of adaptive-immune reactivity (i.e., excessive peri-implant lymphocyte infiltration/activation). We hypothesized that, prior to symptoms, some people with MoM hip arthroplasty will develop quantifiable metal-induced lymphocyte reactivity responses related to peripheral metal ion levels. We tested three cohorts (Group 1: n = 21 prospective longitudinal MoM hip arthroplasty; Group 2: n = 17 retrospective MoM hip arthroplasty; and Group 3: n = 20 controls without implants). We compared implant position, metal-ion release, and immuno-reactivity. MoM cohorts had elevated (p < 0.01) amounts of serum Co and Cr compared to controls as early as 3 months post-op (Group 1:1.2 ppb Co, 1.5 ppb Cr; Group 2: 3.4 ppb Co, 5.4 ppb Cr; Group 3: 0.01 ppb Co, 0.1 ppb Cr). However, only after 1-4 years post-op did 56% of Group 1 develop metal-reactivity (vs. 5% pre-op, metal-LTT, SI > 2), compared with 76% of Group 2, and 15% of Group 3 controls (patch testing was a poor diagnostic indicator with only 1/21 Group 1 positive). Higher cup-abduction angles (50° vs. 40°) in Group 1 were associated with higher serum Cr (p < 0.07). However, sub-optimal cup-anteversion angles (9° vs. 20°) had higher serum Co (p < 0.08). Serum Cr and Co were significantly elevated in reactive versus non-reactive Group-1 participants (p < 0.04). CD4+CD69+ T-helper lymphocytes (but not CD8+) and IL-1β, IL-12, and IL-6 cytokines were all significantly elevated in metal-reactive versus non-reactive Group 1 participants. Our results showed that lymphocyte reactivity to metals can develop within the first 1-4 years after MoM arthroplasty in asymptomatic patients and lags increases in metal ion levels. This increased metal reactivity was more prevalent in those individuals with extreme cup angles and higher amounts of circulating metal. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

xxxx

[this would be me....an asymptomatic patient who would develop lymphocytic reactivity to metals in 4-5 years post implant.  the interesting thing about this is the reference to the significantly elevated interleukin and cytokine levels.  Interesting isn't it that my renal cell carcinoma recurrence would be treated with interleukin and or cytokine therapy!!!

Cytokines (Greek cyto-, cell; and -kinos, movement) are small cell-signaling protein molecules that are secreted by numerous cells and are a category of signaling molecules used extensively in intercellular communication. Cytokines can be classified as proteins, peptides, or glycoproteins; the term "cytokine" encompasses a large and diverse family of regulators produced throughout the body by cells of diverse embryological origin.[1]

The term "cytokine" has been used to refer to the immunomodulating agents, such as interleukins and interferons

An immunomodulator, also known as an immunotherapy is a substance (e. g. a drug) which has an effect on the immune system]


 

No comments:

Post a Comment