Clinical nephrology. Case studies最新文献

Kimura disease (KD) is a chronic benign granulomatous disease. Approximately 20% of patients with KD have renal disease. Membranous nephropathy (MN) is one of the main renal pathologies in KD; however, the underlying mechanism remains unknown. We herein present a 28-year-old male diagnosed with KD after biopsy of a left lower eyelid mass 11 years earlier. He visited our hospital with edema in the lower legs and scrotum. A blood test showed a serum creatinine level of 0.95 mg/dL and serum albumin level of 0.9 g/dL. Urinalysis revealed heavy proteinuria with mild hematuria. Renal biopsy showed spike formation by PAM staining and granular deposits of IgG and C3 in the glomerular basement membrane by direct immunofluorescence microscopy (IF). Electron microscopy revealed subepithelial electron-dense deposits (EDD). IF staining for the phospholipase A2 receptor (PLA2R) was positive in the glomerular basement membrane, leading to a diagnosis of PLA2R-associated MN. Our literature review on MN in KD included 14 cases, all of which exhibited subepithelial EDD, while subendothelial EDD was absent in 10. PLA2R staining was positive in 2 of the 3 cases examined. The results of this case and the literature review suggest the involvement of autoantibodies against podocyte antigens in the pathogenesis of MN in KD. Further studies are needed on these antigens.

Renal cortical necrosis (RCN) is a rare but severe cause of acute kidney injury primarily observed in obstetric complications. We herein present a case of RCN in a 32-year-old Mongolian primigravida transferred to our hospital with uncontrolled massive postpartum hemorrhage. Contrast-enhanced computed tomography revealed ongoing uterine hemorrhage, prompting endovascular intervention for control. It also showed the loss of cortical perfusion in the kidneys, while preserving medullary blood flow, which is consistent with RCN. The patient remained anuric from transfer and required continuous hemodiafiltration followed by intermittent hemodialysis. Renal biopsy on day 23 revealed coagulative necrosis in glomeruli and tubules in the outer cortex, consistent with RCN, while glomeruli in the deeper cortex were spared. Glomeruli in the outer cortex displayed glomerular paralysis. The patient transitioned to peritoneal dialysis (PD) to facilitate infant care at home. Over 6 months, renal function improved, allowing dialysis discontinuation. Four years post-discharge, she remains free of renal replacement therapy, with serum creatinine of 2.67 mg/dL. The present case highlights the potential for gradual renal function improvement in RCN through the recovery of residual nephrons. PD may be a promising modality for patients with RCN.

T-lymphoblastic lymphoma/leukemia (T-LBL) is a rare and aggressive hematologic malignancy characterized by a neoplastic proliferation of immature T lymphocytes that is restricted to nodal/extra-nodal sites with minimal involvement of bone marrow. While T-LBL is the second most frequent subtype of pediatric non-Hodgkin lymphoma, primary renal involvement in T-LBL is exceedingly rare and can pose a significant diagnostic challenge. We present the case of an 11-year-old male who initially presented with new-onset seizure, hypertensive crisis, and acute renal failure. Renal ultrasounds demonstrated enlarged kidneys with loss of corticomedullary differentiation suggestive of medical renal disease. A kidney biopsy was performed, revealing an atypical interstitial T-cell infiltrate with diffuse expression of CD4, CD8, and TdT, raising concern for T-cell acute lymphoblastic lymphoma (instead of leukemia) (T-ALL/LBL). A subsequent bone marrow biopsy was negative, and no other sites of involvement were identified on PET/CT, so chemotherapy was deferred until the diagnosis could be confirmed. The patient re-presented 2 months later with visual changes and diffuse leptomeningeal enhancement on MRI. Repeat kidney biopsy with flow cytometry demonstrated a population of aberrant T cells with CD4/CD8 co-expression. A repeat bone marrow biopsy contained < 1% blasts, and no aberrant lymphocytes were detected in peripheral blood. CT scan revealed new retroperitoneal adenopathy with infiltrative disease involving kidneys, pancreas, adrenal glands, and liver, consistent with stage IV T-LBL.Kidney involvement in acute LBL is uncommon, and renal failure due to leukemic infiltration is rarely reported. This case underscores the importance of performing kidney biopsies in cases of unexplained acute renal failure and considering lymphoma in the differential for interstitial nephritis, even in the absence of abnormal hematological findings.

In this clinical case report, we explore a rare type of renal involvement in a patient with rheumatoid arthritis: the polyclonal variant of immunotactoid glomerulopathy. To date, 26 cases of this rare variant have been reported, and our patient is the second solely associated with rheumatoid arthritis. Our report includes a detailed case description, follow-up, and an extensive review of immunotactoid glomerulopathy with comprehensive differential diagnostic considerations.

All-trans retinoic acid (ATRA) and arsenic trioxide (ATO)-based therapy has become the standard of care in the treatment of acute promyelocytic leukemia (APL). While ATO nephrotoxicity has been rarely reported, data on the specific mechanisms and types of renal injury remain scarce. We present a case of acute kidney injury (AKI) superimposed on chronic kidney disease (CKD) induced by ATO therapy in a patient diagnosed with APL. Biopsy findings revealed acute interstitial nephritis on a background of IgA nephropathy. The AKI resolved after the discontinuation of ATO therapy and initiating steroid treatment. The kidney function remained stable at 6-month follow-up. This case highlights the potential renal complications associated with ATO therapy and highlights the importance of monitoring kidney function in patients undergoing this treatment.

Bartter syndrome (BS) is a rare autosomal recessive disorder characterized by inherited salt-losing tubulopathies. Distinguished into six types, each associated with specific genetic mutations, type II is particularly rare in adults and typically presents early. This report documents a rare case of an adult diagnosed with type II Bartter syndrome that progressed to end-stage kidney disease (ESKD) and underwent successful kidney transplantation, marking it a first of its kind in India and only the second globally. The patient, diagnosed in adulthood, experienced a delayed onset of symptoms, including uremia, hypocalcemia, and medullary nephrocalcinosis, which progressed to ESKD. Genetic testing confirmed a homozygous missense mutation in the KCNJ1 gene. After prolonged hemodialysis, a kidney transplant from a deceased donor resulted in successful graft function and symptom resolution. This case underlines the phenotypic variability of Bartter syndrome and provides critical insights into managing severe, late-onset cases through transplantation.

Introduction: Oxalate nephropathy (ON) is a rare condition caused by calcium oxalate crystal deposition in renal tubules, leading to acute kidney injury (AKI), chronic kidney disease (CKD), or both. The etiologies of ON are divided into two main categories: primary and secondary. Linaclotide is used for the constipation subtype of irritable bowel syndrome (IBS-C), which is not reported to precipitate ON.

Case presentation: We report a unique case of linaclotide-precipitated ON in a 50-year-old female with predisposing comorbidities. The patient developed severe AKI (creatinine 8.37 mg/dL) 3 months after starting linaclotide for IBS-C. Symptoms included fatigue, flank pain, and pale stools. Kidney biopsy confirmed ON. Linaclotide was discontinued, and supportive treatment led to significant renal recovery, with creatinine returning to baseline (0.92 mg/dL) within 2 months.

Discussion: This case highlights linaclotide's potential to precipitate ON in patients with risk factors such as malabsorption and dehydration. Secretory diarrhea caused by linaclotide may increase intestinal oxalate absorption, triggering hyperoxaluria. While not inherently nephrotoxic, linaclotide may exacerbate existing susceptibilities.

Conclusion: Linaclotide can contribute to ON in predisposed patients. Clinicians should consider medication history and risk factors in unexplained AKI and pursuing kidney biopsy for diagnosis.

Introduction: The sudden onset of nephrotic syndrome (NS) and acute interstitial nephritis (AIN) seems to be an uncommon but distinct nonsteroidal anti-inflammatory drug (NSAID)-related renal syndrome.

Case presentation: We present such a case in a patient who took a "magic pill" for gout. Renal biopsy revealed minimal change disease (MCD), acute interstitial nephritis (AIN), severe acute tubular injury (ATI), and IgA nephropathy (IgAN). He was treated with an aborted course of high-dose prednisone, with complete resolution of his renal diseases. The pathologic finding of the combination of MCD and AIN raised the possibility of a drug effect. One of the pills was analyzed and found to be primarily composed of diclofenac. Initially, we considered IgAN a bystander, considering primary IgAN is the most common glomerulonephritis worldwide, especially in Asians and Hispanics. However, the complete resolution of urinary findings after discontinuation of the pill followed by a few days' treatment with prednisone, together with no recurrence of the kidney disease over 6 years, made us speculate that IgAN may have also been triggered by diclofenac.

Conclusion: We presented a case of AIN, MCD, and IgAN associated with diclofenac masquerading as a "herbal" medicine. The cause was suggested by pathology and confirmed with high-resolution liquid chromatography mass spectrometry testing of the pills. A history of NSAID use should be diligently sought in any patient who presents with NS and AIN. In addition, this is the first report of IgAN possibly induced by NSAID without recurrence after 6 years' follow-up.

Introduction: Ankylosing spondylitis (AS) is a chronic, progressive inflammatory disease that primarily affects the spine and sacroiliac joints. In recent years, biologic agents have gained increasing popularity in the treatment of AS due to their high targeting specificity and favorable side effect profiles. Among these, secukinumab has emerged as an effective treatment option. However, the safety and efficacy of secukinumab in patients undergoing hemodialysis has not yet been thoroughly verified.

Case report: Here, we report the successful treatment of AS with secukinumab in a 36-year-old male patient undergoing hemodialysis. The patient presented with recurrent lumbosacral pain and tested positive for HLA-B27. After treatment, significant improvements were observed in both the imaging characteristics of the synovial joints and the patient's symptoms.

Conclusion: This case suggests that secukinumab may have a positive effect on AS in patients on hemodialysis, without apparent adverse effects.

Karyomegalic interstitial nephritis (KIN) is a rare hereditary form of chronic interstitial nephritis that was first described over 50 years ago. It is characterized by karyomegalic tubular epithelial cells and progressive chronic kidney disease, often leading to end-stage renal disease by the fifth decade of life. Recent studies have identified FAN1 mutations as a key genetic contributor, with additional associations to environmental factors and toxic exposures, such as ochratoxin A, alkylating agents, and heavy metals, which may act as potential triggers of the disease. We present a detailed analysis of KIN cases, highlighting genetic diversity, clinical manifestations, and management challenges, complemented by a comprehensive review of the literature.