The etiology or duration of renal failure seems not to be relevant, but NSF risk greatly depends on the residual kidney function. The majority of NSF cases have been identified in patients with stage 5 CKD, but NSF has also developed in patients with stage 4 and 3 CKD, and those with acute kidney injury, even if kidney function subsequently returned to normal following GBCA administration. Thus NSF should be considered as a differential diagnosis in any patient who has been exposed to a GBCA, regardless of the kidney function level.Three GBCAs have been principally implicated in NSF: gadodiamide, gadopentetate dimeglumine, and gadoversetamide, though cases have been reported with majority of GBCAs on the market. High doses in individual GBCA administrations and high cumulative doses of GBCA over the lifetime of patients with renal dysfunction are associated with increased risk of NSF. Mechanism
De-chelation of Gd(III) is responsible for the toxicity associated with gadolinium complexes such as GBCAs, and the toxicity appears to be a consequence of Zn2+, Cu2+, and Ca2+ transmetallation in vivo. This hypothesis is supported by acute toxicity experiments, which demonstrate that despite a 50-fold range of LDse values for four Gd(III) complexes, all become lethally toxic when they release precisely the same quantity of Gd(III). It is also supported by subchronic rodent toxicity experiments, which demonstrate a set of gross and microscopic findings similar to those known to be caused by Zn2+ deficiency.
Pemirolast (INN) is a mast cell stabilizer used as an anti-allergic drug therapy. It is marketed under the tradenames Alegysal and Alamast. Clinical trials studying treatments for allergic conjunctivitis have found that an ophthalmic solution containing levocabastine with pemirolast potassium may be more effective in alleviating symptoms than levocabastine alone.It has also been studied for the treatment of asthma. Pemirolast has appeared as a possible candidate for SARS-CoV-2 (COVID-19) spike protein disruption and interference. Such results were ascertained by molecular dynamics calculations executed on the Summit supercomputer. By simulating compounds with FDA or similar regulatory approval, the authors found 4 interfacial molecules that could potentially disrupt the SARS-CoV-2 interface with ACE-2 receptors, suggesting that such small molecules could mitigate SARS-CoV-2 infection. The 4 candidate interfacial molecules included pemirolast, isoniazid pyruvate, nitrofurantoin, and eriodictyol. References
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