CEN Case Reports最新文献

We report the case of a 39-year-old man who presented with a history of generalized fatigue, nausea, subjective fever with rigors, and renal dysfunction after receiving infliximab (IFX) therapy for Crohn's disease. A renal biopsy revealed acute tubulointerstitial nephritis (ATIN). After other causes of acute kidney injury were excluded, steroid therapy was initiated, his fever subsided, and kidney function improved. From this case report, infliximab could be a rare cause of elevated kidney function and that it should be not considered a completely safe treatment or disregarded as potential cause of ATIN.

Coronavirus disease 2019 (COVID-19) mRNA vaccines have been linked to various kidney adverse events including acute tubulointerstitial nephritis (ATIN). This report describes a 15-year-old female who developed persistent fever and fatigue 54 days after receiving her second dose of the BNT162b2 2 SARS-CoV-2 vaccine. She presented with elevated serum creatinine and urinary β2-microglobulin (β2MG) levels. Kidney biopsy revealed mononuclear infiltrate with some eosinophils, confirming the diagnosis of ATIN. Repeatedly positive lymphocyte transformation test results for the vaccine suggested a relationship between the vaccine and interstitial nephritis. Initially, treatment with prednisolone was effective. However, an increase in urinary β2MG level was observed 7 months later, and the introduction of mycophenolate mofetil (MMF) allowed for the gradual reduction and eventual cessation of prednisolone. This case represents one of the rare pediatric instances of ATIN following COVID-19 vaccination. MMF can be an effective alternative in corticosteroid-dependent cases.

Tubulointerstitial nephritis (TIN) is characterized by inflammation of the renal interstitium with the infiltration of immune cells, mainly consisting of T cells. Recently, patients with TIN with the predominant infiltration of immunoglobulin M (IgM)-positive plasma cells were reported, coined IgMPC-TIN. Here we report the case of a 70-year-old woman diagnosed with Fanconi syndrome and renal tubular acidosis. Renal biopsy revealed IgMPC-TIN. Her renal dysfunction and clinical findings improved after corticosteroid therapy. However, the patient died of progressive liver failure and spontaneous bacterial peritonitis. In laboratory tests, viral hepatitis was excluded, and autoantibodies associated with liver diseases were negative. Generally, IgMPC-TIN is often complicated by primary biliary cholangitis (PBC), whereas her autopsy revealed the local infiltration of IgM-positive plasma cells, obliterative portal venopathy, and nodular regenerative hyperplasia in liver. This case is the first demonstration that IgMPC-TIN is also seen in liver disease with nodular regenerative hyperplasia, although IgMPC-TIN is more common in anti-M2 antibody-positive disease.

Macroscopic hematuria (MH)-associated acute kidney injury (AKI) is a rare condition that causes acute tubular damage due to severe glomerular bleeding with MH. A 66-year-old Japanese woman with no significant past medical history was referred for severe kidney injury with oliguric MH. Her prior medical checkup results showed no occult blood in her urine. Seven days earlier, she had experienced transient severe acute right lumbar back pain. On admission, her serum urea nitrogen was 147 mg/dL, serum creatinine (sCr) 18.3 mg/dL, urinary red blood cells (RBCs) > 100/hpf, urinary protein 28.8 g/gCr, with no hydronephrosis in either kidney, but two stones were found in the right kidney and right ureteropelvic junction. At the start of her hemodialysis, the patient was treated with high-dose steroids because of suspected rapidly progressive glomerulonephritis. A renal biopsy of the left kidney showed acute tubular injury with massive RBC casts filling the tubular lumen. Glomerulitis was not detected, but electron microscopy revealed diffuse glomerular thin basement membrane (TBM). Despite immediate steroid discontinuation, the patient's renal function and MH improved, and she was weaned from hemodialysis. The stones resolved 2 months after onset, but microscopic hematuria persisted for 7 months post-onset. The sCr level was fixed at 1.1 mg/dL 20 months post-onset. This is the first report of MH-AKI in a TBM without the risk of MH-AKI development, such as bleeding tendency or iron overload. In this TBM, a colic attack of the renal urinary tract induced glomerular bleeding, and intolerance to hematuria may have caused severe tubular damage.

Cryptococcosis is the third most common invasive fungal infection in solid-organ transplant (SOT) recipients after candidiasis and aspergillosis. These patients are at risk of disseminated cryptococcosis because of immuosuppressive therapy. The median time to disease onset after kidney transplantation is approximately 35 months and it rarely occurs more than 10 years after transplantation. Herein, we report a case of 64-year-old kidney transplant recipient suffering from coexisting disseminated cryptococcosis with brain and skin involvement, together with cytomegalovirus (CMV) antigenemia more than 20 years after transplant. She presented with frontal headache and bilateral hand tremor, in addition to multiple nodular lesions over bilateral lower limbs. The diagnosis was made after lumbar puncture and skin biopsy. She was successfully treated with a course of anti-fungal and anti-CMV regimen without any relapse of central nervous system infection. Our case illustrates that disseminated cryptococcosis can occur very late after organ transplant. It is thus important to watch out for late-onset opportunistic infections and strike the balance between risks of infections and rejections in SOT patients.

During the unprecedented COVID-19 outbreak, new-onset or relapsing glomerulonephritis, such as ANCA-associated glomerulonephritis and Immunoglobulin A (IgA) nephropathy, following COVID-19 has been reported. However, to date, the association of COVID-19 with preexistent IgA vasculitis (IgAV) remains unclear. Here, we present the case of a 20-something old Japanese woman with preexistent IgAV who newly developed glomerulonephritis following COVID-19. At the diagnosis of IgAV, she had cutaneous purpura, joint pains, and gastrointestinal symptoms, but no signs of kidney involvement. Three months ago, she was tested positive for COVID-19 and subsequently developed hematuria and proteinuria. She was then admitted to our hospital and renal biopsy showed glomerular mesangial expansion and hypercellularity and cellular and fibrocellular crescents, accompanied by diffuse IgA and C3 deposits. With the diagnosis of de novo IgAV nephritis, the patient was treated with intravenous methylprednisolone followed by oral prednisolone. She had favorable responses to this treatment and has achieved and maintained the remission of hematuria and proteinuria after initiation of glucocorticoid therapy. Our case highlights that immune response to SARS-CoV-2 infection could trigger the onset of glomerulonephritis in the IgAV patients who have no renal involvement.

Acute interstitial nephritis (AIN) is known to cause acute kidney injury and is characterized by immunocyte infiltration and interstitial fibrosis. Primary etiologies include drugs, infections, and autoimmune disorders. Herein, we presented the case of a 78-year-old woman patient with AIN with anti-centromere antibody (ACA) positivity, secondary to an idiopathic immune system disorder. Her serum creatinine (sCr) was 0.67 mg/dL 2 months prior to consulting us, which increased to 2.79 mg/dL. The renal biopsy revealed an AIN comprising interstitial infiltration with immunocytes and CD138 + cells. Furthermore, all other antibodies tested negative using immunofluorescence on both glomeruli and tubulointerstitial lesions. The ACA was elevated to a level of ≥ 500 U/mL. The ACA positive has been known to be accompanied by worsening kidney function in patients with systemic sclerosis and primary biliary cholangitis. However, any autoimmune disease were not diagnosed. Successful treatment with an initial dose of 30 mg/day of glucocorticoids tapered to 25 mg/day resulted in a decrease in the sCr to 1.53 mg/dL 4 weeks later. Nine months later, glucocorticoids was tapered, based on the threshold of a sCr of 1.03 mg/dL and the titer of ACA of 291 U/mL. In this case, glucocorticoid treatment remarkably improved renal function in AIN containing CD138 + cells accompanied by a reduction of ACA titer. The etiology of ACA-positive AIN was unknown; however, the incidence of ACA-positive AIN should always be deliberated.

Chronic kidney disease associated with low birth weight and/or premature birth (L/P-CKD) in infants may result from a decreased number of nephrons at birth. These infants may develop acute kidney injury due to exposure to nephrotoxic substances or other events during nephrogenesis in early infancy. Nonetheless, L/P-CKD progression remains unclear. We present three cases of L/P-CKD diagnosed after neonatal intensive care unit (NICU) discharge. Three patients were born extremely prematurely (gestational age, 24-26 weeks) with extremely low birth weight (606-906 g). They were admitted to the NICU (117-311 days) anad received several nephrotoxic medications during the early postnatal period. They showed elevated serum creatinine levels at 4 weeks after birth, which decreased to normal levels at NICU discharge. Proteinuria was first detected during adolescence (10-15 years) on annual school urine screening, with a remarkable increase in their height (18 - 50.8 cm), without known episodes of urinary tract infection, dehydration, lifestyle-related issues, such as excessive salt/protein intake, and extreme lack of exercise that might have caused kidney damage. Their kidneys were smaller than normal on renal ultrasonography. Open renal biopsy findings indicated glomerulomegaly and perihilar glomerulosclerosis in two of the three patients, suggesting glomerular hypertension. The remarkable differences between the body height before CKD and the timing of diagnosis of CKD could contribute to the progress of CKD. Long-term follow-up of low birth weight and extremely premature infants, from NICU discharge until adulthood, should be established.

A middle-aged woman was found to have proteinuria during a health check-up. About sixteen months later, she was diagnosed with stage IIA invasive ductal carcinoma of the right breast. Her proteinuria progressed to nephrotic syndrome with significant hematuria. Hormone therapy was initiated for her estrogen and progesterone receptor-positive breast cancer. A kidney biopsy performed 47 days after starting the therapy revealed an IgA-dominant membranoproliferative glomerulonephritis-like pattern of injury. Electron microscopy showed subendothelial-dominant electron-dense deposits (EDD), with small amounts of mesangial EDD and a single occurrence of subepithelial hump-like EDD, along with occasional mesangial interpositions. Similar pathology can be caused by IgA vasculitis with nephritis, IgA-dominant infection-associated glomerulonephritis, and liver disease-associated glomerulopathy, but all of these were ruled out. The deposited IgA was found to be galactose-deficient IgA1. Thus, IgA nephropathy with glomerular capillary IgA deposition was considered. She underwent a right partial mastectomy and sentinel lymph node biopsy in the right axilla 75 days after starting hormone therapy, followed by adjuvant radiation. Proteinuria and hematuria tended to decrease after the treatment, and this trend continued even after corticosteroid therapy for glomerulonephritis, which was administered 156 days after starting hormone therapy. Approximately 15 months after starting hormone therapy, her proteinuria had reduced to around 1.0 g/g of creatinine, and her hematuria was negative. IgA nephropathy with glomerular capillary IgA deposition is known to be resistant to corticosteroid therapy. The favorable clinical course of the rare glomerulopathy following breast cancer treatment suggested a diagnosis of paraneoplastic glomerulopathy secondary to breast cancer in our patient.