Musculoskeletal sarcoidosis: A single center experience over 15 years

Joint involvement in sarcoidosis: systematic review and meta-analysis of prevalence, clinical pattern and outcome

OBJECTIVES

To characterize joint involvement (JI) in sarcoidosis, a systematic search of MEDLINE, EMBASE and Cochrane Library was conducted from inception to July 2022 for publications reporting its prevalence, pattern, treatment and outcome.

METHODS

The pooled prevalence estimates (PPE) with 95% CI were calculated using binomial distribution and random effects. Meta-regression method was used to examine factors affecting heterogeneity between studies.

RESULTS

Forty-nine articles were identified comprising a total of 8574 sarcoidosis patients, where 12% presented with JI (95% CI 10, 14; I2 = 0%). The PPE for sarcoid arthritis (SA) was 19% (95% CI 14, 24; I2 = 95%), and 32% (95% CI 13, 51; I2 = 99%) for arthralgia. Heterogeneity was due to higher JI prevalence reported in Western Asia and the Middle East, in rheumatology clinics and via surveys. Sample size of SA varied from 12 to 117 cases. Ankles were most frequently affected (PPE 80%) followed by knees and wrists. Monoarthritis was uncommon (PPE 1%; 95% CI 0, 2; I2 = 55%). Acute SA prevailed (PPE 79%; 95% CI 72, 88; I2 = 69%) with an equal proportion of oligo and polyarthritis and was frequently accompanied by erythema nodosum (PPE 62%; 95% CI 52, 71; I2 = 16%). Chronic SA was predominantly polyarticular with a higher frequency of the upper extremity joints affected. Most common non-articular manifestations with SA included fever (52%), erythema nodosum (41%), hilar adenopathy (86%) and interstitial lung disease (23%) of which one-third required corticosteroids and/or immunosuppressants.

CONCLUSION

SA occurred early in the disease with a PPE of 19% and most frequent pattern of acute oligo- or polyarthritis predominantly affecting the lower extremity large joints.

Sarcoidosis, granulomas and myopathy syndromes: A clinical-pathology review

Muscle involvement in sarcoidosis is common by pathologic analysis, but symptomatic disorders are less frequent. Sarcoidosis-related muscle pathology includes non-caseating granulomas, muscle fiber changes that are diffuse or anatomically related to granulomas, and perimysial connective tissue with histiocyte-associated damage. The mechanisms by which granulomas form, enlarge and damage muscle tissues are incompletely understood. Sarcoidosis-related clinical syndromes with muscle involvement include: chronic myopathies with proximal weakness; nodular disorders; subacute onset disorders involving proximal or eye muscles; myalgia or fatigue syndromes; and, possibly, inclusion body myositis-like disorders. Corticosteroid treatment may benefit some syndromes, but clinical trials are necessary.

Association of spondyloarthritis and sarcoidosis: A retrospective observational population-based matched cohort study

OBJECTIVES

To investigate the association between spondyloarthritis (SpA) and sarcoidosis.

METHODS

An observational retrospective population-based matched cohort study was conducted. Using data from the Spanish Minimum Basic Data Set. All the admissions of patients with SpA reported between 1999 and 2015 were analysed and a control group matched by age, sex and year of admission was selected. Crude and age- and sex-adjusted incidence rates for sarcoidosis were calculated. Generalized linear models were used for trend analysis and unconditional logistic regression models for calculating crude and adjusted odds ratios (ORs) to assess the association between sarcoidosis and SpA.

RESULTS

The study database contained data on 214,280 hospitalisations: 107,140 admissions of patients with SpA and 107,140 of patients without SpA. Overall, 220 of the admissions were of patients with sarcoidosis: 133 (0.12%) in the SpA group and 87 (0.08%) in the non-SpA group (P<0.05). The incidence rates of sarcoidosis were 2.68 and 1.64 per 100,000 per year in the SpA and non-SpA groups, respectively. The trend was similar in the two cohorts. Regarding potential associations between SpA and sarcoidosis, the crude and adjusted ORs were 1.52 (95% CI: 1.16-2.01) and 1.50 (95% CI: 1.14-1.97) overall in patients with SpA, with adjusted ORs of 1.42 (95% CI: 1.03-1.94) and 1.81 (95% CI: 1.29-2.55) in patients with ankylosing spondylitis and psoriatic arthritis, respectively.

CONCLUSIONS

There is a relationship that is not due to chance between sarcoidosis and SpA and specifically that sarcoidosis is significantly associated with ankylosing spondylitis and psoriatic arthritis.