Diffuse Idiopathic Skeletal Hyperostosis (DISH)
DISH, also known as ankylosing hyperostosis and Forestier’s disease, is a non-inflammatory disease, with the most common presentation involving calcification and ossification (bone formation) of spinal ligaments and the areas where tendons and ligaments attach to bones.1,2 Though similar in some symptoms, DISH is considered to be different from simple hyperostosis (thickening of bones).
Patients suffering from DISH report a wide variety in manifestations of symptoms. Very often neck, thoracic spine, low back, and/or extremity pain is reported.3 The frequency of complaints among those with DISH varies by the site of discomfort but reports of difficulty swallowing (dysphagia) is a very common feature. This symptom is likely caused by bone formation in the spinal region that compressed the esophagus.
Other common features:
- Generalized tenderness at peripheral ligament/tendon attachment sites
- Recurrent Achilles' tendinitis and shoulder bursitis (inflammation)
- Recurrent lateral or medial epicondylitis
- Bony spurs
- Soft tissue mass adherent to quadriceps, patella, or Achilles' tendon
Causes of DISH
Though the exact mechanism underlying DISH is unknown, many possible causes have been proposed and investigated. These include many dietary and environmental factors that have been associated with simple hyperostosis such as high levels of fluoride and vitamin A exposure. Unfortunately, research has not shown direct causal relationships in any of these to DISH.6,5
Investigators have however identified some associated risk factors. These include:
- Long-term high dose retinoic acid exposure
- Male gender
- Pima Indian decent
- Age over 40 1, 7-11
Your physician is likely to order tests to investigate symptoms that may me consistent with a possible DISH diagnosis. Typically, most people with DISH will have abnormalities of the spine that can be seen on x-rays. Therefore, a physician is likely to order a chest x-ray as an initial screening test. A chest x-ray alone may diagnose up to 75% of those suffering from DISH.12
A chest computed tomography (CT ) scan may also be order as a further diagnostic test as a CT is more sensitive than plain radiography for detecting posterior longitudinal ligamentous calcification (hardening of a spinal ligament) which is a hallmark feature of DISH.13 In addition, neurologic complaints should alert the physician to the possibility of posterior longitudinal ligament involvement, with associated spinal cord compression. There are no consistent laboratory blood findings that are associated with DISH.1, 3, 6
A number of conditions may produce spinal bony changes similar to those of DISH. The two most common conditions that may be mistaken for DISH are spondylosis deformans and ankylosing spondylitis. Both may look very similar in x-ray and CT studies.
Unfortunately, there have been no controlled studies examining the effectiveness of any therapy for DISH.
Some possible treatments that have been suggested to alleviate symptoms include
- Gentle exercise
- Orthotics help with painful heel spurs and assist with ambulation
- Local corticosteroid injections
- Surgery to remedy dysphagia16
- Utsinger, PD. Diffuse idiopathic skeletal hyperostosis. Clin Rheum Dis 1985; 11:325.
- Resnick, D, Shapiro, RF, Wiesner, KB, et al. Diffuse idiopathic skeletal hyperostosis (DISH) [ankylosing hyperostosis of Forestier and Rotes-Querol]. Semin Arthritis Rheum 1978; 7:153.
- Mata, S, Fortin, PR, Fitzcharles, MA, et al. A controlled study of diffuse idiopathic skeletal hyperostosis. Clinical features and functional status. Medicine (Baltimore) 1997; 76:104.
- Schlapbach, P, Beyeler, C, Gerber, NJ, et al. The prevalence of palpable finger joint nodules in diffuse idiopathic skeletal hyperostosis (DISH). A controlled study. Br J Rheumatol 1992; 31:531.
- Troillet, N, Gerster, JC. [Forestier disease and metabolism disorders. A prospective controlled study of 25 cases]. Rev Rhum Ed Fr 1993; 60:274.
- Utsinger, PD, Resnick, D, Shapiro, R. Diffuse skeletal abnormalities in Forestier disease. Arch Intern Med 1976; 136:763.
- Julkunen, H, Knekt, P, Aromaa, A. Spondylosis deformans and diffuse idiopathic skeletal hyperostosis (DISH) in Finland. Scand J Rheumatol 1981; 10:193.
- Julkunen, H, Heinonen, OP, Knekt, P, Maatela, J. The epidemiology of hyperostosis of the spine together with its symptoms and related mortality in a general population. Scand J Rheumatol 1975; 4:23.
- Kiss, C, O’Neill, TW, Mituszova, M, et al. The prevalence of diffuse idiopathic skeletal hyperostosis in a population-based study in Hungary. Scand J Rheumatol 2002; 31:226.
- Cassim, B, Mody, GM, Rubin, DL. The prevalence of diffuse idiopathic skeletal hyperostosis in African blacks. Br J Rheumatol 1990; 29:131.
- Bloom, RA. The prevalence of ankylosing hyperostosis in a Jerusalem population–with description of a method of grading the extent of the disease. Scand J Rheumatol 1984; 13:181.
- Bruges-Armas, J, Couto, AR, Timms, A, et al. Ectopic calcification among families in the Azores: Clinical and radiologic manifestations in families with diffuse idiopathic skeletal hyperostosis and chondrocalcinosis. Arthritis Rheum 2006; 54:1340.
- Trojan, DA, Pouchot, J, Pokrupa, R, et al. Diagnosis and treatment of ossification of the posterior longitudinal ligament of the spine: Report of eight cases and literature review. Am J Med 1992; 92:296.
- Sarzi-Puttini, P, Atzeni, F. New developments in our understanding of DISH (diffuse idiopathic skeletal hyperostosis). Curr Opin Rheumatol 2004; 16:287.
- Fulton, JD. Analgesic use of etidronate in Forrestier’s disease. Lancet 1992; 340:1287.
- Castellano, DM, Sinacori, JT, Karakla, DW. Stridor and dysphagia in diffuse idiopathic skeletal hyperostosis (DISH). Laryngoscope 2006; 116:341.