Sirolimus-induced interstitial lung disease and resolution after conversion to everolimus

The case for the therapeutic use of mechanistic/mammalian target of rapamycin (mTOR) inhibitors in xenotransplantation

The mechanistic/mammalian target of rapamycin (mTOR) is one of the systems that are necessary to maintain cell homeostasis, such as survival, proliferation, and differentiation. mTOR inhibitors (mTOR-Is) are utilized as immunosuppressants and anti-cancer drugs. In organ allotransplantation, current regimens infrequently include an mTOR-I, which are positioned more commonly as alternative immunosuppressants. In clinical allotransplantation, long-term efficacy has been established, but there is a significant incidence of adverse events, for example, inhibition of wound healing, buccal ulceration, anemia, hyperglycemia, dyslipidemia, and thrombocytopenia, some of which are dose-dependent. mTOR-Is have properties that may be especially beneficial in xenotransplantation. These include suppression of T cell proliferation, increases in the number of T regulatory cells, inhibition of pig graft growth, and anti-inflammatory, anti-viral, and anti-cancer effects. We here review the potential benefits and risks of mTOR-Is in xenotransplantation and suggest that the benefits exceed the adverse effects.

Progressive Host-Directed Strategies to Potentiate BCG Vaccination Against Tuberculosis

The pursuit to improve the TB control program comprising one approved vaccine, M. bovis Bacille Calmette-Guerin (BCG) has directed researchers to explore progressive approaches to halt the eternal TB pandemic. Mycobacterium tuberculosis (M.tb) was first identified as the causative agent of TB in 1882 by Dr. Robert Koch. However, TB has plagued living beings since ancient times and continues to endure as an eternal scourge ravaging even with existing chemoprophylaxis and preventive therapy. We have scientifically come a long way since then, but despite accessibility to the standard antimycobacterial antibiotics and prophylactic vaccine, almost one-fourth of humankind is infected latently with M.tb. Existing therapeutics fail to control TB, due to the upsurge of drug-resistant strains and increasing incidents of co-infections in immune-compromised individuals. Unresponsiveness to established antibiotics leaves patients with no therapeutic possibilities. Hence the search for an efficacious TB immunization strategy is a global health priority. Researchers are paving the course for efficient vaccination strategies with the radically advanced operation of core principles of protective immune responses against M.tb. In this review; we have reassessed the progression of the TB vaccination program comprising BCG immunization in children and potential stratagems to reinforce BCG-induced protection in adults.

Role of Fluorodeoxyglucose Positron Emission Tomogram Scan in Sirolimus-Induced Lung Toxicity: A Rare Case Report

Lung toxicity is a rare but serious side effect of sirolimus, a mammalian target of rapamycin inhibitor used as an immunosuppressive agent in solid-organ transplant recipients. We report a case of 67-year-old man who had living-related renal transplant 12 years previously that was complicated by chronic allograft dysfunction. He presented with fever, cough, and shortness of breath, and his chest imaging showed bilateral patchy and ground glass opacities. Before symptoms of lung toxicity, the patient's sirolimus levels were in the range of high normal. Bronchoalveolar lavage ruled out infection, and a transbronchial biopsy was inconclusive. A fluorodeoxyglucose positron emission tomogram scan showed high uptake in the area of lung opacities with a standard uptake value of 4.7. His symptoms improved after he was switched from sirolimus to tacrolimus, and a thoracic computed tomography scan after 6 weeks showed complete resolution. Pulmonary toxicity should be considered in any patient on sirolimus with respiratory symptoms and opacities on chest imaging. The role of fluorodeoxyglucose positron emission tomogram scan in evaluation of sirolimus-induced lung toxicity has not been previously described, and this is the first report of this type of scan finding indicating intense inflammation in this condition.