Genetic kidney diseases are caused by mutations in specific genes that significantly affect kidney development and function. Although the underlying pathogenic genes of many kidney diseases have been identified, an understanding of their mechanisms and effective treatments remains limited. Gene editing, particularly using clustered regularly interspaced short palindromic repeats (CRISPR), has recently become a promising approach for studying genetic diseases and the CRISPR/CRISPR-associated protein 9 (CRISPR-Cas9) method has become a prominent research method. It has been shown that CRISPR-Cas9 can be targeted to knock out specific genomic sites, which enables researchers to correct gene mutations, prevent inheritance, and better understand the function of genes and the effectiveness of drugs. However, the application of CRISPR-Cas9 technology in the development of therapeutic agents against genetic kidney disease has been overlooked compared with other genetic diseases. In this paper, we provide an overview of the current research advancements in genetic kidney diseases using CRISPR technology, as well as the diverse preclinical research methods implemented, with particular emphasis on autosomal dominant polycystic kidney disease.

Alport syndrome (AS) is a hereditary nephropathy characterized by progressive kidney damage that commonly leads to end-stage kidney disease. Early diagnosis is critical, as preemptive nephroprotective therapy, such as angiotensin-converting enzyme inhibitors, can significantly delay disease progression. However, the early diagnosis of AS remains challenging due to the lack of reliable preclinical or screening biomarkers, particularly before the onset of proteinuria. Although nonspecific microhematuria is oftenpresent, itis insufficientfor definitive early detection.Recent studies have identified potential early cellular alterations as candidate biomarkers for the preclinical detection of AS, but none have been widely implemented in clinical practice. This review presents the current knowledge on early biomarkers of kidney damage for AS, highlights promising avenues for future research, and emphasizes the importance of developing effective diagnostic tools to enable timely intervention and improve patient outcomes.

Focal segmental glomerulosclerosis (FSGS), a significant cause of kidney failure in children, is a common pathological diagnosis in cases of idiopathic nephrotic syndrome, especially steroid-resistant ones. FSGS has the potential to recur after kidney transplantation, often leading to graft loss. However, not all children with FSGS experience recurrence posttransplantation, such as those with genetic or secondary forms, which have minimal risk. Moreover, advancements in management, including intensive plasmapheresis and immunosuppressive therapies like rituximab, have increased remission rates in cases of recurrence. Identifying patients at high risk of recurrence, such as those with an initial treatment response or previous failed transplantation, is crucial. These children require close monitoring of proteinuria and prompt, intensive treatment upon recurrence to improve outcomes.

Purpose: Lupus nephritis (LN) can be caused by the complement activation. This study aimed to investigate the differences and clinical implications of the activation pattern of the complement system for pediatric and adult LN patients. Methods: We retrospectively reviewed the medical records of 40 patients (14 pediatric and 26 adult patients) diagnosed with LN through kidney biopsy. Results: The mean ages at diagnosis of pediatric and adult patients were 11.7±2.92 and 37.3±13.5 years, respectively. At the first LN diagnosis, compared with adult patients, pediatric patients had a higher estimated glomerular filtration rate and milder proteinuria; however, there was no statistical significance. The age-adjusted mean serum complement 3 value was significantly lower in the pediatric group (33.0±11.3 mg/dL) than in the adult group (50.8±25.2 mg/dL) (P<0.01).Based on the findings of kidney biopsy, no significant differences were observed in the severity of pathologic classification and the positive rate of complements between adults and children. However, the chronicity index score of adult patients was significantly higher than that of pediatric patients and in the case of complement 4d, despite a similar positive rate, the intensity was significantly stronger for adults (2.35±0.83 vs. 1.54±0.52, P=0.04). Conclusions: The activation pattern of the complement system in LN differs clinicopathologically between pediatric and adult patients and these differences might play an important role in the age-dependent prognosis of LN.

We present an incidentally detected case of bilateral sub-internal limiting membrane (ILM) hemorrhage secondary to typical hemolytic uremic syndrome (HUS) along with a literature review. A 4-year-old girl presented to our emergency department with bloody diarrhea, abdominal pain, fever, and oliguria. HUS was suspected based on clinical symptoms and laboratory findings suggestive of hemolytic anemia, thrombocytopenia, and acute kidney injury. Supportive management, including intermittent dialysis, was provided during admission. However, the patient exhibited central nervous system involvement and presented with a seizure. Despite the absence of visual symptoms, a fundus examination revealed unexpected bilateral sub-ILM hemorrhages and a cotton wool spot in the right eye. Blood dyscrasia improved with repeated hemodialysis and red blood cell transfusions. The sub-ILM hemorrhage gradually resolved, as observed on consecutive fundus photographs. Multimodal retinal imaging revealed healthy capillary structures without evidence of macular ischemia or fibrosis. Typical HUS can be accompanied by a sub-ILM hemorrhage without preceding symptoms. The absence of visual symptoms, despite significant retinal abnormalities, emphasizes the importance of immediate and routine fundus examinations in patients with typical HUS. This proactive approach improves early detection of ocular involvement, enabling prompt intervention to manage potential visual complications, and ultimately improving patient outcomes.