Letter to the Editor
Premature arthritis is a distinct type II collagen phenotype: Comment on the article by Kannu et al
Version of Record online: 28 JAN 2011
Copyright © 2011 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 63, Issue 2, page 569, February 2011
How to Cite
Li, K. and Thorne, C. (2011), Premature arthritis is a distinct type II collagen phenotype: Comment on the article by Kannu et al. Arthritis & Rheumatism, 63: 569. doi: 10.1002/art.30091
- Issue online: 28 JAN 2011
- Version of Record online: 28 JAN 2011
- Accepted manuscript online: 15 OCT 2010 01:46PM EST
To the Editor:
We read with interest the recent report by Kannu et al, in which they describe 2 Australian families with early-onset osteoarthritis (OA) in multiple generations, correlating with COL2A1 mutations (1). Of the type II collagenopathies, Stickler syndrome is most common and is classified into 3 types, each of which has distinct features (Table 1) (2). Kannu and colleagues reported premature onset of degenerative joint disease as being associated with type II collagen mutations but did not classify the additional features suggesting a type III phenotype.
|Feature||Type I||Type II||Type III|
|Ocular||Myopia, vitreoretinal degeneration, cataracts, retinal detachment||Congenital nonprogressive myopia, cataracts||None|
|Musculoskeletal||Mild degenerative changes, hypermobility||Mild degenerative changes, hypermobility||Early-onset osteoarthritis|
|Auditory||Normal to slight hearing impairment||Early-onset sensorineural hearing loss||High-tone sensorineural hearing loss|
|Craniofacial||Cleft palate||Cleft palate||Pierre-Robin sequence|
We previously provided a detailed description of a 42-year-old woman who presented with a 22-year history of primarily bilateral knee pain; this presentation was similar to that of the members of the 2 families described by Kannu et al (2). Specifically, Stickler syndrome type III was distinctly diagnosed based on the clinical features of our patient.
To our knowledge, our group was the first to describe a clinical case of Stickler syndrome type III presenting in an adult, and the diagnosis was made only after the presentation of early OA in family members from 3 generations (3). As in the 2 families described by Kannu et al, the patterns of skeletal and auditory features in the absence of ocular abnormalities should be noted. We agree with Kannu et al that early-onset OA or an unrecognized skeletal dysplasia can be considered a rationale for genetic testing, screening, and surveillance of both past and present family members of a patient with Stickler syndrome. However, the distinction of the type of Stickler syndrome, especially in light of the relevant combination of findings, should be made to direct specific interventions and monitoring.
- 1Premature arthritis is a distinct type II collagen phenotype. Arthritis Rheum 2010; 62: 1421–30., , , , , , et al.
- 2Adult presentation of Stickler syndrome type III. Clin Rheumatol 2010; 29: 795–7., .
- 3Early-onset osteoarthritis due to otospondylomegaepiphyseal dysplasia in a family with a novel splicing mutation of the COL11A2 gene. J Rheumatol 2008; 35: 920–6., , , , , , et al.
Kayi Li BHSc*, Carter Thorne MD, FRCPC, FACP, * University of Toronto, Toronto, Ontario, Canada, The Arthritis Centre, Newmarket, Ontario, Canada.