CEN Case Reports最新文献

Mannitol is an osmotic diuretic that can induce acute kidney injury (AKI) and hypertonic hyponatremia. Rapid mannitol removal and the avoidance of osmotic demyelination syndrome (ODS) by overcorrecting hyponatremia during dialysis are paramount. We present a case of mannitol-induced AKI and hyponatremia in a man in his 50 s with chronic kidney disease and heart failure who was undergoing chemotherapy for seminoma. After mannitol administration as a part of the chemotherapy protocol for forced diuresis, sudden anuric AKI and subsequent volume expansion developed. An estimated mannitol concentration of 728 mg/dL calculated using the osmolar gap (OG) was treated with hemodialysis (HD). Because of concerns regarding ODS caused by rapid serum sodium (sNa) correction by HD, extracorporeal ultrafiltration was initially considered for volume reduction. However, HD was ultimately chosen for mannitol removal; therefore, instead of the measured sNa, tonicity or corrected sodium (cNa) was monitored to account for transcellular free-water shifts between the intracellular and extracellular compartments. In this case, HD effectively removed mannitol, as reflected by the decreased OG, thereby resolving AKI and hyponatremia. Furthermore, tonicity (or cNa) remained stable throughout treatment, and complications were avoided. Prioritizing tonicity (or cNa) over measured sNa is important when managing hypertonic hyponatremia caused by mannitol intoxication.

Therapeutic monoclonal antibodies (mAbs) have revolutionized the treatment landscape of various diseases, offering targeted therapy options with high specificity. Under normal physiological conditions, their size prevents renal excretion. However, there is limited information about mAbs pharmacokinetics in patients with massive proteinuria, a condition often associated with a nephrotic syndrome. In this case report, we describe a 68-year-old man with non-small-cell lung carcinoma (NSCLC) and a paraneoplastic nephrotic syndrome, who was treated with pembrolizumab 200 mg every 3 weeks. Since there is limited data on pembrolizumab disposition in patients with nephrotic syndrome, we monitored pembrolizumab serum and urine concentrations to ensure adequate systemic exposure. Therapeutic drug monitoring results showed no renal excretion of pembrolizumab and therapeutic drug exposure. Treatment of the NSCLC led to an amelioration of the paraneoplastic nephrotic syndrome. We conducted a literature review on the various types of proteinuria and their effects on the excretion of mAbs. Existing literature shows that increased renal clearance of monoclonal antibodies in patients with glomerular proteinuria is possible, but it probably depends on the amount of glomerular proteinuria. Based on literature findings and our own, we suggest that in cases of severe glomerular proteinuria, like nephrotic range proteinuria, the likelihood of renal loss of monoclonal antibodies is higher than in other cases.

Seasonal influenza is prevalent globally, particularly during winter months. It is well documented that this disease causes severe, often fatal complications in hemodialysis patients. While numerous reports have focused on novel influenza viruses, there is a paucity of case reports detailing seasonal influenza viral infections in this patient population. This case presents a 71-year-old male undergoing hemodialysis who developed severe seasonal influenza A pneumonia despite receiving the influenza vaccine and early antiviral treatment. Initially presenting with fever, cough, and myalgia, the patient was diagnosed with influenza A virus infection and hospitalized due to heightened risk associated with dialysis and an elevated inflammatory response. Despite treatment with two different antiviral medications, his condition deteriorated, leading to ARDS (acute respiratory distress syndrome). The administration of steroid pulse therapy resulted in significant clinical improvement. This case underscores the severe nature of influenza virus-related illnesses in dialysis patients, even with vaccination and early antiviral intervention. It also suggests the potential benefit of early steroid pulse therapy in managing severe influenza pneumonia in high-risk individuals.

An 18-year-old female presented with palpable purpura nine months before her hospital admission, which first appeared 1 month after receiving a COVID-19 vaccine and recurred intermittently. One month prior to admission, she developed macrohematuria, abdominal pain, and a loss of appetite. Occult blood in urine had been noted during high school health check-ups. Upon admission, she continued to have macrohematuria, along with renal dysfunction and a nephritic urinalysis, serum myeloperoxidase-anti-neutrophil cytoplasmic antibodies (MPO-ANCA) positivity. A renal biopsy revealed crescentic glomerulonephritis with mesangial and endocapillary hypercellularity, and dominant IgA deposition and electron-dense deposits in the mesangial regions. The diagnosis was IgA nephropathy (IgAN) or IgA vasculitis with nephritis (IgAVN), with a possible overlap of MPO-ANCA-associated glomerulonephritis. Treatment began with methylprednisolone pulse therapy and prednisolone. After the diagnosis, rituximab (RTX) and avacopan were added to the regimen. Within two months, renal function, hematuria, and MPO-ANCA levels had normalized, and proteinuria was almost fully resolved by 13 months. If IgAN/IgAVN and ANCA-associated vasculitis were indeed triggered by the COVID-19 vaccination in this case, it is plausible that both conditions share similar pathologic mechanisms. This case emphasizes the need for a reliable laboratory method to detect pathogenic ANCA to guide both induction and maintenance therapy. Further investigation into the effectiveness of the ANCA-associated glomerulonephritis treatment protocol including corticosteroids, RTX, and avacopan in managing crescentic IgAN/IgAVN could offer valuable insights into improving patient care.

Anti-glomerular basement membrane (GBM) disease causes rapidly progressive glomerulonephritis (RPGN) and has a high mortality rate from lung hemorrhage or infection as a side effect of immunosuppressive treatment. We report a case in which a patient with anti-GBM disease experienced severe jejunal bleeding due to cytomegalovirus (CMV) enteritis during immunosuppressive treatment. A previously healthy 74-year-old female was admitted to our hospital with severe acute kidney injury due to intrinsic kidney disease. The patient was anuric, and hemodialysis was started. The initial serum anti-GBM antibody level was elevated at 1880 U/mL. Kidney biopsy demonstrated global glomerulosclerosis and diffuse crescent formation on light microscopy. Immunofluorescence revealed focal deposition of IgG along the glomerular capillaries. The patient was diagnosed with RPGN secondary to anti-GBM disease, and oral prednisolone and double filtration plasmapheresis (DFPP) were begun. During treatment, the patient developed recurrent jejunal hemorrhage refractory to endoscopic clipping. Surgical resection of the intestine was performed to control bleeding. There were CMV-positive cells within the resected jejunum on immunohistochemistry. CMV antigens were also detected in the serum. The patient was diagnosed with CMV enteritis and treated with ganciclovir. Ultimately, the patient was discharged home without any neurologic problems on the 285th day of hospitalization. When treating severe anti-GBM antibody disease, there is a dilemma between the effectiveness and the side effects, especially infections, of immunosuppressive therapy. In this case, moderate immunosuppressive therapy with corticosteroids and DFPP without cyclophosphamide contributed to controlling the CMV enteritis and the patient's survival.

A 76-year-old Japanese man was incidentally diagnosed with a pancreatic head tumor on computed tomography after surgery for colon cancer. He underwent pancreatoduodenectomy and was diagnosed with IgG4-related autoimmune pancreatitis. Concurrent chronic kidney disease gradually progressed and chronic hemodialysis was introduced 2 years later. Six months after the introduction of hemodialysis, follow-up abdominal computed tomography revealed marked enlargement of bilateral kidneys compared with previous images. Blood tests revealed persistent high IgG and IgG4 levels, and IgG4-related kidney disease was suspected. Thus, percutaneous kidney biopsy was performed. No evidence of IgG4-related kidney disease was detected, and a diagnosis of diffuse large B-cell lymphoma was made. Six courses of combination chemotherapy consisting of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone was effective, and the patient achieved and maintained complete remission for five years. This case highlights the need to consider the possible development of malignant lymphoma within several years after IgG4-related disease, especially in cases of autoimmune pancreatitis.

Type I and mixed cryoglobulinemic vasculitis differ in pathophysiology, clinical presentation, and therapeutic response. We report a case of refractory cryoglobulinemic vasculitis diagnosed following ischemic non-obstructive coronary artery disease (INOCA). The patient presented with dyspnea, as well as abdominal pain due to ischemic enteritis, purpura, and renal failure requiring dialysis. Despite the patient's IgG λ-type monoclonal gammopathy of undetermined significance (MGUS) and negative hepatitis C virus, the presence of rheumatoid factor (RF) activity and the possibility of IgM involvement were suggested by cryoglobulin analysis and strong glomerular IgM deposition. The condition was diagnosed as mixed cryoglobulinemia, and various immunomodulatory treatments, including methylprednisolone, rituximab and plasmapheresis, were administered without achieving cryoglobulin negativity. However, treatment with bortezomib and dexamethasone ultimately led to cryoglobulin negativity and clinical improvement although the patient was not weaned off dialysis, resulting in remission of the cryoglobulinemic vasculitis. This case suggests that bortezomib, a proteasome inhibitor, may be a promising treatment for refractory cryoglobulinemic vasculitis.

In March 2024, a significant public health issue involving red yeast rice supplements emerged in Japan, which may have been associated with several health problems, including kidney dysfunction. A 74-year-old man without a history of urinary abnormalities developed nephrotic syndrome 10 weeks after starting "Beni-Koji Choleste Help^®," a red yeast rice supplement. Electron microscopy showed subepithelial and intramembranous dense deposits with abnormality of the glomerular basement membrane, which led to the diagnosis of long-standing membranous nephropathy. The diagnosis of phospholipase A2 receptor (PLA2R)-positive primary membranous nephropathy was confirmed via PLA2R-positive immunostaining. Furthermore, there were findings of focal tubular necrosis without unexplained cellular infiltration. Based on previous reports, it was suggested that red yeast rice-related products have triggered the acute tubular necrosis in the patient. His nephrotic syndrome reached partial remission with oral administration of prednisolone at an initial dose of 40 mg/day. This case indicates that membranous nephropathy was coincidentally accompanied by acute tubular necrosis that was potentially associated with red yeast rice-related health foods. It may be reasonable to state that individuals consuming red yeast rice-related health products may develop subclinical focal tubular necrosis even in the absence of overt clinical symptoms or laboratory abnormalities. The currently recognized health issues associated with red yeast rice-related health foods may only represent a small portion of the overall risks.

Several cases of glomerulonephritis occurring after infection with human parvovirus B19 (PVB19) have been reported. However, the pathogenesis and clinicopathological features of PVB19-related glomerulonephritis remain elusive. We describe the case of a 34 year-old woman who showed nephrotic syndrome and microscopic hematuria 10 days after PVB19 infection. Blood pressure and renal function were within normal ranges. Laboratory tests showed positive results for anti-PVB19 immunoglobulin (Ig)M antibody and complement 3 (C3) hypocomplementemia. Antibody to streptolysin O (ASO) was slightly elevated, but bacterial cultures yielded no colonies. Light microscopy of renal biopsy was compatible with membranoproliferative glomerulonephritis (MPGN). Immunofluorescence microscopy showed intense staining for C3 and faint staining for IgG on the glomerular capillary wall and paramesangial area. Electron micrography showed subendothelial electron-dense deposits (EDDs), but hump-shaped subepithelial EDDs were not evident. PBV19-DNA was absent from renal tissue. Moreover, glomeruli showed positive staining for nephritis-associated plasmin receptor (NAPlr) and plasmin activity with similar distribution. Around 6 months after PVB19 infection, levels of anti-PVB19 IgM antibody spontaneously tuned negative with an apparent reduction of proteinuria and improvement of hypocomplementemia, although ASO level remained unchanged. This appears to represent the first description of positive glomerular staining for NAPlr in MPGN after PVB19 infection. Based on a review of 27 cases, including our own case, the MPGN lesions could be attributable to PVB19 infection. Clinicopathological features of this case were incompatible with post-streptococcal acute glomerulonephritis. We presume that a PBV19-derived glomerular pathogen that cross-reacts with anti-NAPlr antibody might be involved in the development of PVB19-related MPGN.