Tic-Borne Disorders Causing Chronic Arthritis? Save

Findings from a population based cross-sectional study suggests that while up to 20% of patients have antibodies to tick-borne exposures, only a minority reported musculoskeletal symptoms. 

Lyme disease is one of many tick-borne diseases (TBDs) that may include spotted fever group rickettsiosis, ehrlichiosis, galactose-α-1,3-galactose (α-gal) syndrome, and variable MSK symptoms, beg the question whether chronic disease may be attributed to prior tick exposure.

Clinical data and serum samples were derived from the Johnston County Osteoarthritis project (2017-2018) that included noninstitutionalized White and Black Johnston County residents 45 years of age or older.  The primary outcome was seropositivity with Ehrlichia IgG, Rickettsia IgG, and/or α-gal IgE and musculoskeletal symptoms.

A total of 488/605 JoCo OA project patients included serum samples (80.7%). The 488 participants had a median age of 72 years and participants were 69% female, 33% Black and (67% White. The prevalence of seropositivity was:

• 8.6% Ehrlichia IgG
• 17.1% Rickettsia IgG
• 19.6% α-gal IgE

Only α-gal IgE positivity was associated with knee pain, aching or stiffness (mean ratio 1.30).  Elevated α-gal IgE levels (>0.1 IU/mL) was significantly associated with male sex (OR, 2.63), current smoker (OR 3.55), and an attached tick bite in the past 5 years (OR 3.99).

Antibodies to Rickettsia, Ehrlichia, and α-gal were not associated with symptomatic radiographic knee osteoarthritis.

Although 17% of persons recalled a tick bite in the past 5 years, 36.5% had evidence of prior tick-borne exposure, suggesting frequent human-tick interactions in this population.

This cross-sectional sub-study from the Johnston County Osteoarthritis project shows no clear association between tick bite seropositivity and chronic musculoskeletal symptoms or osteoarthritis.

Further investigation is needed into the pathogenesis of α-gal syndrome (AGS), a potentially life-threatening allergic condition, related to a Lone Star tick bite, and a resultant alpha-gal allergy (also called red meat allergy or tick bite meat allergy). Thus, AGS, is potentially a tick bite related allergic reaction to red meat or mammalian products. MSK symptoms appear to be a minor remote sequelae to this more serious immediate systemic allergic disorder.