Severe Acute Kidney Injury and Double Tubulopathy Due to Dual Toxicity Caused by Combination Antiretroviral Therapy

An in silico molecular modeling approach of halolactone derivatives as potential inhibitors for human immunodeficiency virus type-1 reverse transcriptase enzyme

Acquired Immune Deficiency Syndrome (AIDS) is an infectious disease caused by Human Immunodeficiency Virus (HIV) infection and its replication requires the Reverse Transcriptase (RT) enzyme. RT plays a key role in the HIV life cycle, making it one of the most important targets for designing new drugs. Thus, in order to increase therapeutic options against AIDS, halolactone derivatives (D-halolactone) that have been showed as potential non-nucleoside inhibitors of the RT enzyme were studied. In the present work, a series of D-halolactone were investigated by molecular modeling studies, combining Three-dimensional Quantitative Structure-Activity Relationship (3 D-QSAR), molecular docking and Molecular Dynamics (MD) techniques, to understand the molecular characteristics that promote biological activity. The internal and external validation parameters indicated that the 3 D-QSAR model has good predictive capacity and statistical significance. Contour maps provided useful information on the structural characteristics of compounds for anti-HIV-1 activity. The docking results showed that D-halolactone present good complementarity by the RT allosteric site. In MD simulations it was observed that the formation of enzyme-ligand complexes were favorable, and from the free energy decomposition it was found that Leu100, Val106, Tyr181, Try188, and Trp229 are key residues for stabilization in the enzymatic site. Thus, the results showed that the proposed models can be used to design promising HIV-1 RT inhibitors. Communicated by Ramaswamy H. Sarma.

How to use COVID-19 antiviral drugs in patients with chronic kidney disease

Antiviral drugs such as Remdesivir (Veklury), Nirmatrelvir with Ritonavir (Paxlovid), Azvudine, and Molnupiravir (Lagevrio) can reduce the risk for severe and fatal Coronavirus Disease (COVID)-19. Although chronic kidney disease is a highly prevalent risk factor for severe and fatal COVID-19, most clinical trials with these drugs excluded patients with impaired kidney function. Advanced CKD is associated with a state of secondary immunodeficiency (SIDKD), which increases the susceptibility to severe COVID-19, COVID-19 complications, and the risk of hospitalization and mortality among COVID-19 patients. The risk to develop COVID-19 related acute kidney injury is higher in patients with precedent CKD. Selecting appropriate therapies for COVID-19 patients with impaired kidney function is a challenge for healthcare professionals. Here, we discuss the pharmacokinetics and pharmacodynamics of COVID-19-related antiviral drugs with a focus on their potential use and dosing in COVID-19 patients with different stages of CKD. Additionally, we describe the adverse effects and precautions to be taken into account when using these antivirals in COVID-19 patients with CKD. Lastly, we also discuss about the use of monoclonal antibodies in COVID-19 patients with kidney disease and related complications.

A Synopsis of Current Theories on Drug-Induced Nephrotoxicity

The overriding goal of the treatment of patients is its effectiveness and safety. However, all medications currently being used also exert some adverse pharmaceutical reactions, which may be regarded as an unintended but inevitable cost of pharmacotherapy. The kidney, as the main organ that eliminates xenobiotics, is an organ especially predisposed and vulnerable to the toxic effects of drugs and their metabolites during their excretion from the body. Moreover, some drugs (e.g., aminoglycosides, cyclosporin A, cisplatin, amphotericin B, and others) have a "preferential" nephrotoxicity potential, and their use is associated with an increased risk of kidney damage. Drug nephrotoxicity is, therefore, both a significant problem and a complication of pharmacotherapy. It should be noted that, currently, there is no generally recognized definition of drug-induced nephrotoxicity and no clear criteria for its diagnosis. This review briefly describes the epidemiology and diagnosis of drug-induced nephrotoxicity and characterizes its pathomechanisms, including immunological and inflammatory disturbances, altered kidney blood flow, tubulointerstitial injury, increased lithogenesis-crystal nephropathy, rhabdomyolysis, and thrombotic microangiopathy. The study also lists the basic drugs with nephrotoxicity potential and provides a short overview of the preventive methods for reducing the risk of drug-related kidney damage developing.

Drug-Induced Acute Kidney Injury

Medications are a common cause of AKI especially for patients admitted to hospital wards and the intensive care unit. Although drug-related kidney injury occurs through different mechanisms, this review will focus on three specific types of tubulointerstitial injury. Direct acute tubular injury develops from several medications, which are toxic to various cellular functions. Their excretory pathways through the proximal tubules contribute further to AKI. Drug-induced AKI may also develop through induction of inflammation within the tubulointerstitium. Medications can elicit a T cell-mediated immune response that promotes the development of acute interstitial nephritis leading to AKI. Although less common, a third pathway to kidney injury results from the insolubility of drugs in the urine leading to their precipitation as crystals within distal tubular lumens, causing a crystalline-related AKI. Intratubular obstruction, direct tubular injury, and localized inflammation lead to AKI. Clinicians should be familiar with the pathogenesis and clinical-pathologic manifestations of these forms of kidney injury. Prevention and treatment of AKI relies on understanding the pathogenesis and judiciously using these agents in settings where AKI risk is high.

The Crystalline Nephropathies

Crystalline nephropathies are a unique form of kidney disease characterized by the histologic finding of intrarenal crystal deposition. The intrinsic nature of some molecules and ions combined with a favorable tubular fluid physiology leads to crystal precipitation and deposition within the tubular lumens. Crystal deposition promotes kidney injury through tubular obstruction and both direct and indirect cytotoxicities. Further kidney injury develops from inflammation triggered by these crystals. From a clinical standpoint, the crystalline nephropathies are associated with abnormal urinalysis and urinary sediment findings, tubulopathies, acute kidney injury (AKI), and/or chronic kidney disease (CKD). Urine sediment examination is often helpful in alerting clinicians to the possibility of crystal-related kidney injury. The identification of crystals within the kidneys on biopsy by pathologists prompts clinicians to evaluate patients for medication-related kidney injury, dysproteinemia-related malignancies, and certain inherited disorders. This review will focus on the clinical and pathologic aspects of these 3 categories of crystalline nephropathies.

Kidney transplant dysfunction in a patient with COVID - 19 infection: role of concurrent Sars-Cov 2 nephropathy, chronic rejection and vitamin C-mediated hyperoxalosis: case report

Background

COVID-19 infection in kidney transplant recipients often lead to allograft dysfunction. The allograft injury has various histopathological manifestations. Our case illustrates the unusual combination of allograft rejection, acute kidney injury secondary to oxalate nephropathy and SARS CoV-2 nephropathy as the cause of irreversible allograft failure.

Case presentation

A 56 year old renal allograft recipient presented with a history of fever and diarrhoea for the preceding 4 weeks, tested positive for Sars-CoV2 on nasal swab and was found to have severe allograft dysfunction, necessitating haemodialysis. He subsequently underwent an allograft biopsy, which demonstrated antibody mediated rejection along with the presence of extensive oxalate deposition in the tubules. Ultrastructural examination demonstrated spherical spiked particles in the glomerular capillary endothelium and the presence of tubulo-reticular inclusions suggestive of an active COVID-19 infection within the kidney. The intra-tubular oxalate deposition was considered to be the result of high dose, supplemental Vitamin C used as an immune booster in many patients with COVID − 19 infection in India.

Conclusions

This case highlights the complex pathology that may be seen in following COVID-19 disease and the need for kidney biopsies in these patients to better understand the aetiology of disease.