Relapsing Peritoneal Dialysis-Associated Peritonitis due to Kocuria rhizophila: A Case Report.

Introduction: The Kocuria genus, encompassing gram-positive coccoid actinobacteria belonging to the Micrococcaceae family, has recently been discovered residing on the human skin and oral flora. Reports of Kocuria-associated infections in humans have been scarce. Herein, we present the first case of relapsing peritoneal dialysis (PD)-associated peritonitis caused by Kocuria rhizophila. Case Presentation: The patient, a 78-year-old male, presented with turbid effluent PD fluid, accompanied by an elevated white blood cell count of 253 cells/µL, of which 59% were neutrophils. A diagnosis of PD-associated peritonitis was established, leading to the initiation of intraperitoneal administration of ceftazidime and vancomycin. Subsequently, Kocuria rhizophila was identified through the bacterial culture of the dialysate. On the seventh day of initial treatment, the antibiotic regimen was changed to penicillin G, and the patient underwent a 3-week course of antibiotics. However, 1 week after discharge, the patient's dialysis fluid became cloudy once again, with subsequent detection of Kocuria rhizophila in the fluid culture. Ultimately, the decision was made to remove the patient's PD catheter and transition to hemodialysis. Conclusion: PD-associated peritonitis attributed to Kocuria species may be considered a potential risk for recurrence.

Infection-Related Cryoglobulinemic Glomerulonephritis with Serum Anti-Factor B Antibodies Identified and Staining for NAPlr/Plasmin Activity Due to Infective Endocarditis.

In this rare case of infection-related cryoglobulinemic glomerulonephritis with infective endocarditis, a 78-year-old male presented with an acute onset of fever and rapidly progressive glomerulonephritis. His blood culture results were positive for Cutibacterium modestum, and transesophageal echocardiography showed vegetation. He was diagnosed with endocarditis. His serum immunoglobulin M, IgM-cryoglobulin, and proteinase-3-anti-neutrophil cytoplasmic antibody levels were elevated, and his serum complement 3 (C3) and C4 levels were decreased. Renal biopsy results showed endocapillary proliferation, mesangial cell proliferation, and no necrotizing lesions on light microscopy, with strong positive staining for IgM, C3, and C1q in the capillary wall. Electron microscopy showed deposits in the mesangial area in the form of fibrous structures without any humps. Histological examination confirmed a diagnosis of cryoglobulinemic glomerulonephritis. Further examination showed the presence of serum anti-factor B antibodies and positive staining for nephritis-associated plasmin receptor and plasmin activity in the glomeruli, suggesting infective endocarditis-induced cryoglobulinemic glomerulonephritis.

The Effect of Add-on Acetazolamide to Conventional Diuretics for Diuretic-resistant Edema Complicated with Hypercapnia: A Report of Two Cases.

We herein report two cases in which add-on acetazolamide to furosemide was effective for diuretic-resistant volume overload and hypercapnia. Case 1 was a woman in her 40s presenting with volume overload due to the nephrotic syndrome with diabetes mellitus. Case 2 was a man in his 60s with fluid overload and non-nephrotic proteinuria and sepsis. In both cases, although fluid overload was resistant to high-dose loop diuretics and complicated with hypercapnia due to pulmonary effusion, add-on acetazolamide administration resulted in symptom resolution. The additional effect of acetazolamide occurred regardless of the degree of proteinuria and kidney function.

Functional analysis of suspected splicing variants in CLCN5 gene in Dent disease 1.

BACKGROUND: In recent years, the elucidation of splicing abnormalities as a cause of hereditary diseases has progressed. However, there are no comprehensive reports of suspected splicing variants in the CLCN5 gene in Dent disease cases. We reproduced gene mutations by mutagenesis, inserted the mutated genes into minigene vectors, and investigated the pathogenicity and onset mechanisms of these variants. METHODS: We conducted functional splicing assays using a hybrid minigene for six suspected splicing variants (c.105G>A, c.105+5G>C, c.106-17T>G, c.393+4A>G, c.517-8A>G, c.517-3C>A) in CLCN5. We extracted information on these variants from the Human Gene Mutation Database. We reproduced minigene vectors with the insertion of relevant exons with suspected splicing variants. We then transfected these minigene vectors into cultured cells and extracted and analyzed the mRNA. In addition, we conducted in silico analysis to confirm our minigene assay results. RESULTS: We successfully determined that five of these six variants are pathogenic via the production of splicing abnormalities. One showed only normal transcript production and was thus suspected of not being pathogenic (c.106-17T>G). CONCLUSION: We found that five CLCN5 variants disrupted the original splice site, resulting in aberrant splicing. It is sometimes difficult to obtain mRNA from patient samples because of the fragility of mRNA or its low expression level in peripheral leukocytes. Our in vitro system can be used as an alternative to in vivo assays to determine the pathogenicity of suspected splicing variants.

Characterization of ligV essential for catabolism of vanillin by Sphingomonas paucimobilis SYK-6.

The vanillin dehydrogenase gene (ligV), which conferred the ability to transform vanillin into vanillate on Escherichia coli, was isolated from Sphingomonas paucimobilis SYK-6. The ligV gene consists of a 1,440-bp open reading frame encoding a polypeptide with a molecular mass of 50,301 Da. The deduced amino acid sequence of ligV showed about 50% identity with the known vanillin dehydrogenases of Pseudomonas vanillin degraders. The gene product of ligV (LigV) produced in E. coli preferred NAD+ to NADP+ and exhibited a broad substrate preference, including vanillin, benzaldehyde, protocatechualdehyde, m-anisaldehyde, and p-hydroxybenzaldehyde, but the activity toward syringaldehyde was less than 5% of that toward vanillin. Insertional inactivation of ligV in SYK-6 indicated that ligV is essential for normal growth on vanillin. On the other hand, growth on syringaldehyde was only slightly affected by ligV disruption, indicating the presence of a syringaldehyde dehydrogenase gene or genes in SYK-6.