CEN Case Reports最新文献

Gitelman syndrome is a rare, autosomal recessively inherited tubulopathy manifesting with hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. Common symptoms include fatigue, myalgia, reduced performance capacity, tetany, paresthesia, and delayed growth. However, as reported in the literature, diagnosis in some patients is prompted by an incidental finding of hypokalemia. GS develops due to mutations in the SLC12A3 gene, which encodes the thiazide-sensitive Na-Cl cotransporter. Many variants in the SLC12A3 gene causing GS have been reported in literature. A new pathogenic homozygous mutation (c.2612G > T), absence of hypomagnesemia, and accompanying autoimmune thyroiditis are remarkable in our patient. There are a few Gitelman syndrome cases that are complicated with autoimmune thyroiditis in the literature. In this study, we present a case of Gitelman syndrome with a novel homozygous mutation and accompanying autoimmune thyroiditis and review of the literature.

Autosomal dominant polycystic kidney disease (ADPKD) is a major cause of end-stage kidney disease (ESKD). Vasopressin plays a pivotal role in ADPKD progression; therefore, the selective vasopressin V2 receptor antagonist tolvaptan is used as a key drug in the management of ADPKD. On the other hand, sodium-glucose cotransporter-2 inhibitors (SGLT2i), which may possibly stimulate vasopressin secretion due to the diuretic effect of the drug, have been shown to have both renal and cardioprotective effects in various populations, including those with non-diabetic chronic kidney disease. However, the effect of SGLT2i in patients with ADPKD have not been fully elucidated. Herein, we report the case of a patient with ADPKD on tolvaptan who was administered the SGLT2i dapagliflozin. The patient was a Japanese woman diagnosed with ADPKD at age 30. Despite the treatment with tolvaptan, eGFR was gradually declined from 79.8 to 50 ml/min/1.73 m² in almost 5 years and 10 mg of dapagliflozin was initiated in the hope of renoprotective effects. Although a small increase in vasopressin levels was observed, eGFR decline rate was moderated after dapagliflozin initiation. This case suggested an additional renoprotective effect of dapagliflozin in patient with ADPKD receiving tolvaptan. Although there is no evidence about the renal protective effect of SGLT2i in patients with ADPKD, we hereby report a case successfully treated with dapagliflozin for approximately 2 years. Further research, including clinical trials, is needed to evaluate whether SGLT2i are effective in patients with ADPKD.

Recently, several target antigens of membranous nephropathy (MN), such as phospholipase A2 receptor (PLA2R) and exostosin 1/exostosin 2 (EXT1/2), have been discovered. A 30-year-old woman was referred to our hospital with nephrotic range proteinuria and microscopic hematuria. She was first noted to have proteinuria before pregnancy, and her proteinuria worsened in the postpartum period. A renal biopsy showed MN. Immunofluorescence microscopy showed IgG, IgA, IgM, C3, C4, and C1q depositions in the mesangial area and glomerular capillary walls (GCWs). Regarding the IgG subclass, IgG1 and IgG3 were detected on glomeruli. Electron microscopy showed subepithelial electron-dense deposits (EDDs). EDDs were also detected in paramesangial and subendothelial areas. The diagnosis of membranous lupus nephritis (MLN) was suspected, but she did not fulfill the criteria for systemic lupus erythematosus. Neither anti-nuclear antibody nor hypocomplementemia were detected. We further evaluated glomerular EXT1/2 expressions, which were evident on GCWs. In addition, PLA2R was also detected on GCWs, although serum antibody for PLA2R was negative. She responded to immunosuppressive therapy with decreased proteinuria. In the present case, glomerular PLA2R expression implied the possibility of primary MN. However, pathological findings with a full-house staining pattern and glomerular EXT1/2 expressions were very similar to those of lupus-associated MN. Glomerular PLA2R expression appeared not to reflect immunocomplexes of PLA2R and autoantibody when considering the results for glomerular IgG subclass and the absence of serum anti-PLA2R antibody. Collectively, it is plausible that this was a case of a relatively young postpartum female who developed latent MLN rather than primary MN.

A 74-year-old Japanese male with lung squamous cell carcinoma received his first dose of immune checkpoint inhibitors (ICIs): ipilimumab and nivolumab. He developed acute kidney injury (AKI) and was admitted to our department. We diagnosed kidney immune-related adverse effects (irAE), and a kidney biopsy revealed acute tubulointerstitial nephritis. We started oral prednisolone (PSL) and his AKI immediately improved. The patient maintained stable findings after PSL was tapered off. However, seven months after the ICI administration, he developed rapid progressive glomerular nephritis and was admitted to our department again. The second kidney biopsy showed findings consistent with anti-glomerular basement membrane glomerulonephritis. Although the patient was treated with pulse methylprednisolone followed by oral PSL and plasma exchange, he became dependent on maintenance hemodialysis. To our knowledge, no case report has described two different types of biopsy-proven nephritis. In cases of suspected relapsing kidney irAEs, both a relapse of previous nephritis and the development of another type of nephritis should be considered.

Clostridium perfringens can rarely cause severe systemic infections, usually from an abdominal source, associated with massive hemolysis, which is usually fatal. Hemolytic anemia and acute renal injury resulting from toxin action are critical for the development of multiple organ dysfunction syndrome (MODs), making this condition a real emergency, requiring multispecialty skills and aggressive multimodal therapies. We herein describe a case of septic shock from acute cholecystitis with massive hemolysis caused by C. perfringens in a 55 year-old man that was successfully treated with early blood purification and continuous renal replacement therapy (CRRT) along with antibiotic therapy and surgery. The effect of the enormous amount of toxins produced by Clostridium which elicit a strong cytokine response and the damage caused by the hemolysis products are the main pathogenetic mechanisms of this rare but lethal clinical entity. The main goal of treatment is to remove toxins from plasma, block toxin action, and further production by achieving bacterial killing with antimicrobial agents and controlling the infectious focus, remove waste products and prevent or limit multiorgan damage. Blood purification techniques play an important role due to a strong pathophysiological rationale, as they can remove toxins and cytokines as well as cell-free products from plasma and also replace renal function. Although this condition is rare and robust data are lacking, blood purification techniques for C. perfringens-induced massive hemolysis are promising and should be further explored.

The incidence rate of malignancy in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is higher than that in the general population. Malignancy has been indicated to be a risk factor or inducer of AAV. Herein, we report the case of a healthy 84-year-old man with seronegative microscopic polyangiitis (MPA) after the diagnosis of renal pelvic carcinoma. Four weeks before admission, his estimated glomerular filtration rate (eGFR) was 85 ml/min/1.73 m², and no hematuria or proteinuria was detected. Renal biopsy on admission revealed invasive urothelial carcinoma of the right renal pelvis. On day 15, his eGFR decreased to 30 ml/min/1.73 m² without any incitement. The renal specimen extracted via right robot-assisted nephroureterectomy indicated the presence of ANCA-associated glomerulonephritis. On day 37, urinary protein/urinary creatinine level of 6.48 g/gCre, serum albumin level of 2.1 mg/dL, and eGFR of 20 ml/min/1.73 m² indicated the presence of nephrotic syndrome. His blood sputum was analyzed via chest computed tomography, which revealed alveolar hemorrhage. Although his myeloperoxidase-ANCA was negative, he was diagnosed with MPA based on the 2022 American College of Rheumatology/European League Against Rheumatism classification criteria. This is the first case report of  MPA or AAV complicated with renal pelvic carcinoma. The clinical indicators demonstrated that renal pelvic carcinoma preceded the onset of MPA. The spatial proximity of both diseases indicated that renal pelvic carcinoma had some influence on MPA development via the mechanism of inflammatory cytokines or neutrophil extracellular traps. Our report may be useful in elucidating the mechanism of MPA development.

Duchenne muscular dystrophy (DMD) is an inherited disease characterized by progressive degeneration of the skeletal muscles. Renal dysfunction in patients with DMD has recently become more apparent as life expectancy has increased owing to advances in respiratory devices and heart failure therapies. A 23-year-old man with DMD who required nasal tube feeding was referred to our hospital with a 4-month history of renal dysfunction and anemia. The patient's serum creatinine (sCr) level was within the normal range (0.84 mg/dL), but his serum cystatin C level and estimated glomerular filtration rate calculated by cystatin C (5.90 mg/L and 7.5 mL/min/1.73 m², respectively) indicated severe renal impairment. A urinalysis revealed elevated levels of protein and tubular markers. The patient's hemoglobin and erythropoietin levels indicated renal anemia. Hypotension, a collapsed inferior vena cava, and a poor tube feeding episode suggested that the kidney injury was due to renal ischemia, which progressed to tubulointerstitial kidney injury, an intrinsic kidney injury. The angiotensin-converting enzyme inhibitors and beta-blockers were discontinued, and extracellular fluid was infused. Thereafter, the patient's renal function recovered. Subsequently, the patient's urinary findings and anemia improved. Although advances in cardioprotective agents are expected to improve the prognosis of patients with DMD, it is important to consider that the number of patients with kidney injury due to renal ischemia may increase and that it is difficult to evaluate renal function using sCr level in patients with DMD because of decreased skeletal muscle mass.

Occasionally, patients undergoing dialysis develop acute severe hypotension that requires interruption of dialysis within minutes of initiating every dialysis session. Although the underlying causes of recurrent intradialytic hypotension are evaluated extensively, including dialysis-associated allergic reactions or other possible causes, the definitive cause is sometimes missed. Dialysis is a life-sustaining procedure; therefore, prompt identification and management of the underlying cause of dialysis intolerance are crucial. Herein, we report three cases of patients undergoing dialysis who presented with hypereosinophilia-associated acute intradialytic hypotension. All three patients developed acute severe hypotension within minutes after the start of every dialysis session. The prescriptions for dialysis were changed, but episodes of intradialytic hypotension persisted. Pretreatment with methylprednisolone given intravenously before the dialysis session was also ineffective. All patients had hypereosinophilia (> 1500/μL) of different etiology. Eosinophil-lowering therapy with 0.5 mg/kg of prednisolone given orally daily was initiated, and all of them could restart dialysis without any hypotensive episodes within a few days. Our case report and literature review indicated that hypereosinophilia, regardless of its etiology, could result in severe acute hypotension shortly after the start of dialysis session. The oral administration of prednisolone daily was highly effective on hypereosinophilia-associated intradialytic hypotension, while pretreatment with intravenous corticosteroid therapy just before dialysis had no effect. Hypereosinophilia-associated acute intradialytic hypotension is an under-recognized condition; therefore, clinicians need to be aware of this clinical entity and initiate effective treatment strategies. We also provide a brief summary of previously published cases.

Pseudo-Bartter/Gitelman syndrome (PBS/PGS) is a disorder that presents with hypokalemia and metabolic alkalosis resembling Gitelman syndrome (GS) due to secondary factors, such as lifestyle and /or medicines. Notably, PBS/PGS is more likely to cause renal dysfunction than GS. We report the first case of PBS/PGS due to long-term laxative abuse leading to end-stage kidney disease (ESKD). The patient was a 49-year-old woman with a history of constipation since school, who had used excessive doses of laxatives on her own judgment for nine years at least from 22 years of age. Two years later, blood tests revealed hypokalemia (serum K 3.1 mEq/L), and nine years later, the patient's renal function began to deteriorate (Cr-eGFR 48.7 mL/min/1.73 m²). Since abuse of laxatives was suspected as the cause, it was changed to the proper dosage of laxatives. At 33 years, the patient developed acute kidney injury (AKI), due to a urinary tract infection, and required intensive treatment, including hemodialysis. Although the patient was eventually weaned off dialysis, the renal function did not recover to pre-AKI levels. In suspected GS, comprehensive genetic testing for renal disease-related genes was performed; however, no obvious pathogenic variants were identified. Thereafter, despite decreasing the laxative doses and potassium supplementation, her renal function continued to decline. At 49 years, the patient developed ESKD and was started on maintenance hemodialysis. PBS/PGS is a disease that can lead to ESKD. An early diagnosis of PBS/PGS is crucial to prevent renal function deterioration, and the underlying causes should be removed immediately.

A 50-year-old man who had undergone a living-donor kidney transplant 12 years prior for chronic renal failure due to autosomal dominant polycystic kidney disease contracted coronavirus disease 19 (COVID-19). He had a positive antigen test, mild symptoms, sore throat, and fever of 37.9 ℃. The patient was treated with molnupiravir for 5 days, and the symptoms disappeared 5 days after onset. However, 10 days after onset, he developed a fever of approximately 37 ℃ and a non-productive cough; 27 days after onset, the patient was hospitalized for anorexia and a worsening respiratory condition. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen test results on admission were negative, and no antiviral medications were administered against SARS-CoV-2. Computed tomography revealed extensive ground-glass opacities in both lung fields. The patient was treated with steroid pulse therapy, ceftriaxone, atovaquone, azithromycin, and respiratory management using a high-flow nasal cannula. The combined therapies were successful, and the patient was managed with a nasal oxygen cannula after 3 days. Oxygen administration was discontinued after 6 days of hospitalization, and the patient was discharged after 14 days. Based on the laboratory findings, bacterial, interstitial, and Pneumocystis pneumonia were unlikely. The success of the steroid pulse therapy suggested that respiratory failure was caused by pneumonia due to the immune response after COVID-19 infection.