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Understanding the potential drought impacts on agricultural production is critical for ensuring global food security. Instead of providing a deterministic estimate, this study investigates the likelihood of yield loss of wheat, maize, rice and soybeans in response to droughts of various intensities in the 10 largest producing countries. We use crop-country specific standardized precipitation index (SPI) and census yield data for 1961–2016 to build a probabilistic modeling framework for estimating yield loss risk under a moderate (−1.2 80% probability that wheat production will fall below its long-term average when experiencing an exceptional drought, especially in USA and Canada. As for maize, India shows the highest risk of yield reduction under droughts, while rice is the crop that is most vulnerable to droughts in Vietnam and Thailand. Risk of drought-driven soybean yield loss is the highest in USA, Russian and India. Yield loss risk tends to grow faster when experiencing a shift in drought severity from moderate to severe than that from extreme to the exceptional category, demonstrating the non-linear response of yield to the increase in drought severity. Sensitivity analysis shows that temperature plays an important role in determining drought impacts, through reducing or amplifying drought-driven yield loss risk. Compared to present conditions, an ensemble of 11 crop models simulated an increase in yield loss risk by 9%–12%, 5.6%–6.3%, 18.1%–19.4% and 15.1%–16.1 for wheat, maize, rice and soybeans by the end of 21st century, respectively, without considering the benefits of CO2 fertilization and adaptations. This study highlights the non-linear response of yield loss risk to the increase in drought severity. This implies that adaptations should be more targeted, considering not only the crop type and region but also the specific drought severity of interest.

Managing primary or even secondary glomerulonephritis remains a challenge to many nephrologists. In primary focal segmental glomerulosclerosis (FSGS) with heavy proteinuria, renin aldosterone system blockade and high dose of oral prednisolone is the mainstay of treatment. Other immunosuppressive medications like Cyclophosphamide, Cyclosporine A and Mycophenolate Mofetil (MMF) are warranted if a complete remission is not achieved. We illustrate a case of 21 year old gentleman with primary FSGS that was difficult to achieve remission despite on high dose steroid and oral Cyclophosphamide. He was also not responsive to a combination of MMF and Cyclosporine A (CSA) and even throughout the therapy he developed significant steroid and CSA toxicity. He presented to our center with severe nephrotic syndrome and acute kidney injury requiring acute haemodialysis. Despite re-challenged him again on high dose prednisolone, total of 2.4g of intravenous Cyclophosphamide, and MMF, he failed to achieve remission. He was subsequently given intravenous Rituximab 500mg/weekly for 4 doses and able to attained remission for 1 year. He relapsed again and a second course of Rituximab 500mg/weekly for 6 doses were given to attain remission. This case demonstrates the difficulty in managing refractory steroid dependent FSGS and we found that Rituximab is proven beneficial in this case to induce remission.