Posttranslational modifications in psoriatic arthritis: A systematic literature review.

BACKGROUND AND AIMS: Psoriatic arthritis (PsA) is an inflammatory complex condition. Posttranslational modifications influence almost all aspects of normal cell biology and pathogenesis. The aim of this systematic review was to collect all published evidence regarding posttranslational modifications in PsA, and the main outcome was to evaluate an association between disease outcomes and specific posttranslational modifications in PsA. METHODS: A systematic electronic search was performed in Medline, PubMed, Cochrane, Virtual Health Library, and Embase databases. A total of 587 articles were identified; 59 were evaluated after removing duplicates and scanning, of which 47 were included. A descriptive analysis was conducted, with results grouped according to the type of posttranslational modification evaluated. The protocol was registered at the PROSPERO database. RESULTS: Seven posttranslational modifications were identified: citrullination, carbamylation, phosphorylation, glycosylation, acetylation, methylation, and oxidative stress. Anti-citrullinated peptide and anti-carbamylated protein have been evaluated in rheumatoid arthritis. There is now information suggesting that these antibodies may be helpful in improving the diagnosis of PsA and that they may demonstrate a correlation with worse disease progression (erosions, polyarticular involvement, and poor treatment response). Glycosylation was associated with increased inflammation and phosphorylation products related to the expression of SIRT2 and pSTAT3 or the presence of Th17 and cytokine interleukin-22, suggesting a possible therapeutic target. CONCLUSIONS: Posttranslational modifications often play a key role in modulating protein function in PsA and correlate with disease outcomes. Citrullination, carbamylation, phosphorylation, glycosylation, acetylation, methylation, and oxidative stress were identified as associated with diagnosis and prognosis.

Chronic inflammatory demyelinating polyradiculoneuropathy in a patient with systemic lupus erythematosus without systemic activity.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an uncommon subtype of peripheral neuropathy, especially in systemic lupus erythematosus (SLE). We report a case of SLE presenting with CIDP successfully treated. The patient presented with bilateral, progressive, ascending, sensory, and motor neuropathy. Electrodiagnostic tests reported active motor and sensitive demyelinating polyneuropathy, and the diagnosis of CIDP was confirmed according to the European Federation of Neurological Societies/Peripheral Nerve Society criteria. Initial management with intravenous immunoglobulin and high-dose steroids was administered, then 6-month intravenous cyclophosphamide was initiated with improvement according to clinical scales. In conclusion, CIDP in SLE is rare, reported in just 0.2%. Immunosuppressive therapy should be considered whether initial improvement is not evidenced, as seen in our case requiring cyclophosphamide; interestingly, systemic activity was in remission as the peripheral nervous system is not part of neurological compromise, and we suggest evaluating this unusual presentation into rheumatological practice.