Israel Medical Association Journal

In the absence of definitive anti-viral therapy, there is considerable interest in mitigating against severe inflammatory reactions in coronavirus disease-2019 (COVID-19) pneumonia to improve survival. These reactions are sometimes termed cytokine storm. PDE4 inhibitors (PDE4i) have anti-inflammatory properties with approved indications in inflammatory skin and joint diseases as well as chronic obstructive pulmonary disease (COPD). Furthermore, multiple animal models demonstrate strong anti-inflammatory effects of PDE4i in respiratory models of viral and bacterial infection and also after chemically mediated lung injury. The rationale for PDE4i use in COVID-19 patients comes from the multimodal mechanism of action with cytokine, chemokine, and other key pathway inhibition all achieved with an excellent safety profile. We highlight how PDE4i could be an overlooked treatment from the rheumatologic and respiratory armamentarium, which has potential beneficial immune-modulation for treating severe COVID-19 pneumonia associated with cytokine storms. The proposed use of PDE4i is also supported by age-related immune changes in inflammation severity in PDE4i modifiable pathways in primate coronavirus disease. In conclusion, over-exuberant anti-viral immune responses in older patients with COVID-19 may pose a substantial risk to patient survival and mitigation against such hyper-inflammation with PDE4i, especially with anti-viral agents, is a strategy that need to be pursed, especially in older patients

Enthesitis is a term that refers to inflammation at tendon, ligament, or joint capsule insertions. The entheses are increasinlgly considered to be the primary site of joint inflammation in the spondyloarthropathies including psoriatic arthritis (PsA). Great advances have occurred in the understanding of enthesopathy, which has resulted in a better understanding of the etiopathogenesis of PsA. Enthesitis is difficult to assess on both clinical examination and on imaging because of the overlap in features between mechanical, degenerative, and inflammatory pathologies. Ultrasonography frequently detects entheseal abnormalities in patients with psoriasis, despite the absence of clinical symptoms of arthropathy and the longitudinal value of such lesions for PsA prediction remains unknown. The role of magnetic resonance imaging (MRI) in the assessment and monitoring of enthesitis is not fully agreed on but it is clearly superior for the assessment of spinal polyenthesitis and for diffuse peri-enthseal osteitis that can occur anywhere in the skeleton. Nuclear medicine, including conventional positron-emission tomography (PET) and high-resolution PET scan (hrPET), is more of a research tool for enthesitis and can, for example, help distinguish between PsA and osteoarthritis. Entheseal abnormalities are common in osteoarthritis, which creates diagnostic difficulty from PsA. Entheseal changes, especially on imaging, may also occur in rheumatoid arthritis (RA) and likely reflect the extension of the inflammatory process from the adjacent synovium. The nail is anatomically anchored to the skeleton via a mini-enthesis network. An association between ultrasonography determined distal interphalageal joint (DIP) extensor tendon enthesopathy and clinical nail disease was found, which highlights the pivotal role of the enthesis in this PsA risk factor. This review summarizes the relevant insights and implication of imaging for enthesitis, primarily in PsA but also in other arthropathies.