The current study was initiated to evaluate renal nucleotide-binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome pathway activation and macrophage subtype distribution and their clinicopathological significance in a cohort of oxalate-induced acute kidney injury. Methods: Twelve patients with biopsy-proven acute oxalate nephropathy (AON) from January 2016 to October 2022 were retrospectively enrolled, with estimated glomerular filtration rate (eGFR)-matched 24 patients with acute tubulointerstitial nephritis (ATIN) as disease control. Pathological lesions as well as markers of NLRP3 inflammasome pathway and macrophage phenotype detected by immunohistochemistry staining were semi-quantitatively analyzed. Results: Oxalate depositions were found in 5% to 20% of tubules with a positive correlation with Sirius Red staining in AON specimens (rp = 0.668, p = 0.02). Disruption of tubular basement membrane and inflammatory cell reaction was more prominent in specimens of AON (both p < 0.05) as compared with ATIN specimens. The expressions of NLRP3, caspase-1, and gasdermin D were significantly increased in AON specimens as well (all p < 0.05). Patients with M1/M2 macrophage ratio <1 were found with more chronic tubulointerstitial lesions and presented with lower eGFR at the last follow-up (24.8 ± 10.6 mL/min/1.73 m2 vs. 55.1 ± 21.2 mL/ min/1.73 m2, p = 0.02) in the AON group. Conclusion: The NLRP3 inflammasome pathway was activated in the kidneys of AON patients, and the ratio of M1 and M2 macrophages was associated with chronicity of pathological changes, which needs further exploration.

The paper reports a case of coenzyme Q10 deficiency nephrotic syndrome associated with coenzyme Q2 gene mutation and reviews the literature on this topic. The patient presented with hematuria, proteinuria, and a diminution of vision as clinical manifestations. But the proteinuria was not relieved after sufficient doses of glucocorticoids for over 2 months. The patient′s birth history was unremarkable, and his parents were both healthy and not consanguineous. Whole exome sequencing revealed that the patient had a mutation of coenzyme Q2 gene at c.973A>G(p.T325A) and c.517C>T(p.R173C). Combined with renal biopsy pathology, the patient was diagnosed with hereditary nephropathy and started the supplements of coenzyme Q10 after stopping glucocorticoid treatments immediately. After 5 weeks of therapy, the patient′s 24-h urine protein quantification decreased from 6.01 g to 1.53 g.