Preface

The kidneys, ureters, bladder, and urethra play an important role not only in urine production and transport but also in preventing the invasion of pathogens. In this book, experts from different countries demonstrate clinical and research advances in nephropathy and urinary tract infection.

Membranous nephropathy is a kind of antibody-mediated autoimmune glomerular disease. In their chapter, Dr. Omar Ragy et al. present the gene polymorphism in patients with membranous nephropathy, as well as discuss the value of proteomics and transcriptomic analysis in managing the disease. These modern techniques of analysis make it possible to minimize patients' immunosuppression exposure and identify the most effective targeted immunosuppressive therapy for each patient.

Diabetic nephropathy is a common cause of end-stage kidney disease. Interestingly, not all patients with diabetes mellitus will develop diabetic nephropathy. In their chapter, Drs. Elfiani Elfiani and Huntari Harahap present a cross-sectional comparative study to identify potential biomarkers for the occurrence of diabetic nephropathy.

A kidney transplant is considered the best treatment for patients with end-stage kidney disease. However, some conditions, such as antibody-mediated rejection and recurrent focal segmental glomerulosclerosis, may result in graft failure. Therapeutic apheresis is believed to be an effective treatment for managing these conditions since it can remove donor-specific antibodies and other circulating factors. In their chapter, Drs. Jean Jeanov Filipov and Emil Paskalev Dimitrov demonstrate the current evidence on the application of therapeutic apheresis.

Apart from urine transport, storage, and elimination, the urinary tract also acts as a barrier preventing pathogens from invading. Once pathogens break through the barrier, people will suffer from urinary tract infections. Due to the wide use of antibiotics, some bacteria have developed resistance to these drugs. In their chapter, Dr. Akosua Bonsu Karikari et al. present the characteristics of multidrug-resistant organisms isolated from patients with urinary tract infections in Northern Ghana.

Escherichia coli is the common pathogen causing urinary tract infection. Multidrug-resistant Escherichia coli has attracted broad attention. Dr. Shiela Chetri points out multidrug efflux pumps encoded in the microorganism's chromosomes are the main antibiotic-resistant mechanism in *E. coli*.

*Acinetobacter baumannii* is a kind of opportunistic bacteria related to hospitalacquired infection. In their chapter, Dr. Hussein O.M. Al-Dahmoshi et al. reveal the virulence factors of *A. baumannii* resulting in urinary tract infection. This information allows clinicians to develop targeted treatment strategies.

Besides the evolution of bacterial virulence, some conditions can also cause the body to be susceptible to urinary tract infection. Of those, pregnancy is one of the most common since it may result in temporary ureteral dilation and hydronephrosis. In their chapter, Drs. Muhamed Ali Al Kabe and Eman Th. Nadhaif Al-Fatlawy perform a case-control study that shows pregnant women are at significantly increased risk of bacteriuria.

An intact urothelium and a normal anatomical structure of the urinary tract are the foundation of a powerful barrier. Iatrogenic injury is a common factor that impairs epithelial integrity and consequently weakens the function of the barrier. In general, ureteric injuries in gynecology surgery are one of the most common Iatrogenic injuries of the urinary tract. Dr. Rama Garg presents the diagnosis, treatment, and prevention of ureteric injury in gynecology surgery.

Although this book does not cover all aspects of urinary tract infection and nephropathy, it provides readers with important updates.

> **Ran Pang** Department of Urology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China

Section 1 Introduction
