Idiopathic membranous nephropathy and synchronous mononeuritis multiplex secondary to idiopathic small vessel vasculitis.

Membranous nephropathy has been associated with demyelinating polyneuropathies and antiglomerular membrane disease; however, an association with vasculitic neuropathy has not been described. This case describes a patient with biopsy-proven idiopathic membranous nephropathy and synchronous mononeuritis multiplex secondary to idiopathic small vessel vasculitis, who presented with lower limb microvascular ischaemia, peripheral neuropathy and active urinary sediment. Her extensive non-invasive screening for immunological disease and radiological investigations for occult malignancy were unremarkable. The patient received intravenous methylprednisolone and intravenous rituximab induction therapy resulting in complete remission of both the idiopathic membranous nephropathy and small vessel vasculitis at 7 months post treatment.

Neonatal nephrotic syndrome: all is not gloomy.

Congenital nephrotic syndrome (CNS) is a rare clinical syndrome with a constellation of proteinuria, hypoalbuminaemia and oedema, presenting within 3 months of birth. We present a rare case of neonatal nephrotic syndrome with a probable sepsis induced aetiology. The neonate was referred at day of life 15 with Klebsiella pneumonia sepsis and anasarca. On investigation, the patient had nephrotic range proteinuria, hypoalbuminaemia, generalised anasarca and ascites. The neonate was started on broad-spectrum antibiotics and furosemide. Genetic and other secondary causes of CNS were ruled out. With supportive management and resolution of sepsis, the neonate improved. This case highlights the rare cause of sepsis-induced nephrotic syndrome (NS), which required only supportive treatment without the need for aggressive management of CNS.

Antiepileptic drug-induced severe granulomatous interstitial nephritis.

Granulomatous interstitial nephritis (GIN) is a type of tubulointerstitial nephritis characterised by tubulointerstitial infiltration of mononuclear cells and eosinophils. It accounts for about 6% of all tubulointerstitial nephritis and is detected in ∼0.5%-0.9% of all renal biopsies. GIN has been linked to several antibiotics, non steroidal anti-inflammatory drugs (NSAIDs), and granulomatous disorders like tuberculosis and sarcoidosis but is rarely reported with anti-epileptic medications like phenytoin and levetiracetam. We present a case report of a man in his early 20's with previously normal renal function who developed GIN following levetiracetam and phenytoin consumption for 7 years. After withdrawal of the causative drug and starting steroid therapy, his kidney function gradually improved. In cases of GIN, medication history is important in the evaluation of aetiology.

Polyarteritis nodosa presenting with posterior reversible leukoencephalopathy syndrome.

A man in his 20s presented following a generalised tonic-clonic seizure on a background of a recent diagnosis of hepatitis B (HBV). During admission, he was severely hypertensive and imaging findings confirmed a diagnosis of posterior reversible leukoencephalopathy syndrome (PRES). The patient subsequently developed multiorgan involvement with an axonal sensorimotor neuropathy, vascular cutaneous lesions and multiple bilateral renal and splenic infarcts. Based on the 2012 Revised International Chapel Hill Consensus Criteria, a diagnosis of polyarteritis nodosa (PAN) with secondary PRES was made. The patient was given intravenous methylprednisolone, followed by a prolonged course of oral prednisolone, and tenofovir antiviral therapy to target HBV seroconversion. He made a good neurological recovery with resolution of imaging changes. This case highlights the importance of a low threshold for systemic screening for young patients presenting with PRES secondary to uncontrolled hypertension and the importance of viral screening, particularly for HBV.

Primary biliary cholangitis presenting with Fanconi syndrome: an important phenotype.

A woman in her 50s was referred to nephrology clinic due to progressive chronic kidney disease. She exhibited features of proximal renal tubulopathy, namely Fanconi syndrome, including normoglycaemic glycosuria, normal anion gap metabolic acidosis, and intermittent hypouricaemia and hypophosphataemia. Kidney biopsy showed tubulointerstitial inflammation and focal chronic damage. In addition, antimitochondrial antibodies were present and she had abnormal liver blood tests. A unifying diagnosis of primary biliary cholangitis with an associated renal tubulopathy and interstitial nephritis was made. She was commenced on sodium bicarbonate, ursodeoxycholic acid and oral prednisolone, leading to an improvement in liver biochemistry. Kidney function was stabilised, but a sustained improvement was not seen. This case acts as a reminder of the rare association of tubulointerstitial nephritis and Fanconi syndrome with primary biliary cholangitis, which may be an under-recognised phenotype.

Case of idiopathic multicentric Castleman's disease: the master mimicker.

A woman in her 20s with no medical history presented with progressive abdominal distension, right-sided abdominal discomfort, fatigue and nausea. Examination showed multifocal lymphadenopathy and hepatomegaly with tense ascites. Investigations revealed a multisystem inflammatory condition characterised by elevated acute phase reactants, anaemia, thrombocytopenia, acute kidney injury, lymphocytic ascites, hypoalbuminaemia and hypergammaglobulinaemia. HIV and human herpes virus-8 tests were both negative. In the presence of elevated ANA and SS-A/Ro antibodies, the patient was suspected to be carrying a connective tissue disease, most likely systemic lupus erythematosus (SLE). Clinical and laboratory findings fulfilled the diagnostic criteria for SLE. However, lymph node biopsy showed interfollicular plasmacytosis, associated with high interleukin 6 (IL-6) and vascular endothelial growth factor titers, together hinting towards a rare diagnosis of multicentric Castleman's disease (MCD). As we investigated further, renal biopsy was consistent with thrombotic microangiopathy which has been previously reported in MCD. Furthermore, immune staining on the renal biopsy was negative for 'full-house' immunoglobulin and complement staining pattern, which is specific for lupus nephritis, helping us exclude SLE. In light of these new findings, the patient was started on anti-IL-6 therapy which provided a successful outcome.

IgA vasculitis with severe renal manifestation.

IgA vasculitis is a rare systemic vasculitis in adults, frequently more severe than in paediatric age. It manifests with cutaneous, articular, gastrointestinal and renal involvement.We present a case of a man in his 40s diagnosed with IgA vasculitis with cutaneous, joint, gastrointestinal and renal disease. Significant proteinuria and renal biopsy findings demonstrating crescentic glomerulonephritis led to the onset of early immunosuppression with corticoid and cyclophosphamide. This case report reflects a case of more severe renal impairment due to IgA vasculitis with good outcome with the chosen therapy. The findings in the renal biopsy after treatment supported the good response to the chosen immunosuppression.

Epstein-Barr virus reactivation induced myeloperoxidase-specific antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis.

We present a patient with systemic symptoms including 4 months of dyspnoea worsened with exertion, fatigue, rhinorrhoea, intermittent facial swelling, generalised lymphadenopathy and weight loss. Laboratory studies demonstrated proteinuria and eosinophilia. His serology was consistent with Epstein-Barr Virus (EBV) reactivation. A lymph node biopsy was consistent with EBV-associated reactive lymphoid hyperplasia. He was told to continue symptomatic treatment for EBV infection. After several admissions, vasculitis workup and myeloperoxidase-antineutrophil cytoplasmic autoantibody (ANCA) studies were positive. Evolution of clinical symptoms, laboratory parameters and our literature review suggested the diagnosis of EBV-associated ANCA vasculitis. Steroids were started after the patient continued to deteriorate; the viral load started increasing, so we added valganciclovir with favourable clinical response and no relapse during the follow-up for 6 months. This suggests that with evidence of viraemia (primary or reactivation), antiviral treatment likely has clinical benefit while immunosuppression is being considered.

Not all that is 'full house' is systemic lupus erythematosus: a case of membranous nephropathy due to syphilis infection.

We describe an unusual case of membranous nephropathy precipitated by syphilis infection in a patient without systemic lupus erythematosus (SLE). A previously healthy 20-year-old man presented with leg and facial swelling. Laboratory investigation revealed nephrotic range proteinuria, acute kidney injury, hypocomplementaemia and a highly positive rapid plasma reagin. Kidney biopsy showed membranous nephropathy with 'full-house' immunofluorescence (IgG, IgA, IgM, C1q and C3), mimicking lupus nephritis class Vb. However, the patient had no features of SLE and had negative antinuclear and anti-double-stranded DNA antibodies. He was treated with high-dose methylprednisolone and mycophenolate mofetil for lupus nephritis and with penicillin for syphilis. After 2 months of therapy, his proteinuria resolved, and his renal function and C4 level normalised. This case illustrates that syphilis infection can be a mimicker of lupus nephritis. A literature review suggests that ful-house nephropathy may occur independently of lupus nephritis and may or may not develop into SLE.

Worsening membranous nephropathy in a patient with GIST treated with sunitinib.

Tyrosine kinase inhibitors (TKI) are anticancer agents widely used for a variety of malignancies including gastrointestinal stromal tumours (GIST). Although generally well-tolerated, TKIs have been associated with a number of adverse events including hypertension, proteinuria and nephrotic syndrome. We present the case of a 70-year-old patient with metastatic GIST on long-standing sunitinib who developed hypertension, oedema and hypoalbuminemia with a rising serum creatinine and was found to have nephrotic syndrome. Workup revealed elevated antiphospholipase A2 receptor (PLA2R) antibody IgG titres and a kidney biopsy confirmed PLA2R-positive membranous nephropathy without findings of thrombotic microangiopathy. Cessation of sunitinib led to reduction in anti-PLA2R antibody IgG titres while resumption, due to concern for cancer progression, led to worsening symptoms. Treatment with rituximab led to undetectable anti-PLA2R IgG titres. We highlight the importance of maintaining a systematic approach for evaluating nephrotic syndrome and provide a case showing that TKIs can exacerbate underlying nephrotic syndrome.

Anti-glomerular basement membrane disease and IgA nephropathy in a patient with previous renal cell carcinoma.

A 66-year-old Asian woman presented with severe kidney injury, microscopic haematuria and subnephrotic range proteinuria with elevated serum anti-glomerular basement membrane (anti-GBM) titre. She had a history of renal cell carcinoma. Renal biopsy revealed dual pathology with immunofluorescence showing 3+ linear glomerular IgG staining and 3+ IgA mesangial staining. Cellular crescents were present on light microscopy and electron microscopy revealed increased mesangial matrix. She was treated with plasma exchange and immunosuppression and remained in stage 4 chronic kidney disease. This case describes the coexistence of anti-GBM disease and IgA nephropathy, a phenomenon not well described in the literature. The report also explores the association of malignancy and glomerulonephritis as well as the role of genetics and the utility of human leukocyte antigen (HLA) typing in risk stratification.

Atypical presentation of allergic interstitial nephritis likely induced by ciprofloxacin.

Though the prevalence of drug induced allergic interstitial nephritis (AIN) appears to be increasing, the diagnostic and treatment strategies still remain vague. We present a 56-year-old man with a history of hypertension, chronic kidney disease stage IIIa, recent exposure to ciprofloxacin who presented with acute kidney injury. Though the suspicion of AIN was high, his urinary sediment was bland, that is, no leucocytes or leucocyte casts. A renal biopsy subsequently showed features of AIN correlating with a resolving phase of inflammation. Given the resolving nature of the pathology, we chose not to complete a course of corticosteroids despite his need for temporary haemodialysis. He was able to fully recover his renal function. In this report, we emphasise the unreliable nature of the urinary sediment in the diagnosis of AIN, the utility of a renal biopsy in helping to guide treatment, and the controversial data in corticosteroid treatment.

Proliferative glomerulonephritis with monoclonal immunoglobulin deposits associated with parvovirus B19.

Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) is included in the group of dysproteinaemias causing renal disease. Only a minority of cases are associated with a haematological malignancy. Two cases have been linked to acute parvovirus B19 infections. We report a 36-year-old African-American woman who presented with renal dysfunction, proteinuria, haematuria and a kidney biopsy reported as PGNMID with IgG3-kappa deposits. Her evaluation for a haematological malignancy was unrevealing. Her parvovirus IgM and IgG levels were positive. The patient was initially treated with an ACE inhibitor and spontaneously remitted with minimal proteinuria after 1 month. Repeat parvovirus B19 serologies 6 months later showed persistent IgG and DNA by PCR positivity but IgM negativity. Given the clinical scenario, we believe that her PGNMID was induced by acute parvovirus B19 infection, which appeared to resolve once her acute infection abated. In this report, we describe our latest understanding of PGNMID.

Early onset calciphylaxis following acute kidney injury secondary to anti-glomerular basement membrane antibody disease.

Calciphylaxis is commonly associated with end-stage renal disease (ESRD) and renal transplant. We present a rare case of early onset calciphylaxis in a patient presenting with acute kidney injury (AKI) secondary to anti-glomerular basement membrane (anti-GBM) antibody disease. A 65-year-old obese Caucasian woman with type 2 diabetes mellitus and hypertension presented with a 1-month history of painless gross haematuria and worsening lower extremity oedema. Laboratory results indicated AKI and nephrotic-range proteinuria. Anti-glomerular antibodies were elevated. Renal biopsy revealed focal crescentic glomerulonephritis with linear capillary immunoglobulin G staining consistent with anti-GBM antibody disease. She was treated with haemodialysis, plasmapheresis, steroids, bumetanide and cyclophosphamide. Two months later, she developed necrotic lesions on bilateral thighs. Wound biopsy was consistent with calciphylaxis. This case highlights that calciphylaxis, usually seen in patients with chronic kidney disease or ESRD, can manifest in patients with AKI as well.

A case of ramucirumab-induced renal failure with nephrotic-range proteinuria and its pathological findings.

Ramucirumab-induced renal dysfunction is rarely reported. The pathology of ramucirumab-associated nephropathy in past reports primarily shows thrombotic microangiopathy (TMA) lesions but podocytopathy is not yet known. We report a case of kidney injury induced by ramucirumab in a 71-year-old man with cecal cancer. He was referred to our department for increasing serum creatinine (Cr) levels from 1.08 mg/dL to 2.56 mg/dL after changing anticancer drugs from bevacizumab to ramucirumab. He showed nephrotic-range proteinuria (12.1 g/gCr). A renal biopsy revealed endothelial cell injuries, such as TMA and podocytopathy with epithelial cell hyperplasia, which looked like a crescent. After discontinuing ramucirumab, his renal function and proteinuria improved, as seen by his Cr levels and proteinuria which decreased to 1.74 mg/dL and 1.21 g/gCr, respectively, in 3 months. Unlike previous reports, we found that ramucirumab caused podocyte injuries.

Fibrillary glomerulonephritis or complement 3 glomerulopathy: a rare case of diffuse necrotising crescentic glomerulonephritis with C3-dominant glomerular deposition and positive DNAJB9.

Fibrillary glomerulonephritis (FGN) and complement 3 glomerulopathy (C3G) are rare forms of glomerulonephritis with distinct aetiologies. Both FGN and C3G can present with nephritic syndrome. FGN is associated with autoimmune disease, dysproteinaemia, malignancy and hepatitis C infection. C3G is caused by the unregulated activation of the alternative complement pathway. We present a rare case of diffuse necrotising crescentic glomerulonephritis with dominant C3 glomerular staining on immunofluorescence-consistent with C3G-but electron microscopy (EM) findings of randomly oriented fibrils with a mean diameter of 14 nm and positive immunohistochemistry for DNAJB9-suggestive of FGN. To the best of our knowledge, this is the first reported case of FGN to show dominant C3 glomerular deposits. This case report reaffirms the utility of EM in the evaluation of nephritic syndrome and highlights the value of DNAJB9-a novel biomarker with a sensitivity and specificity near 100% for FGN.

Light chain proximal tubulopathy with cast nephropathy in monoclonal gammopathy of renal significance.

Kidney tubular disorders due to monoclonal immunoglobulin light chains are common manifestations of B-cell neoplasm. Cast nephropathy (CN) is the most frequent type of these disorders and may present with acute kidney injury (AKI) due to the presence of excess light chains in the distal tubules. Light chain proximal tubulopathy (LCPT) is an uncommon form of renal disease and may present as Fanconi syndrome due to proximal tubular cell damage by intracellular deposition of light chains. The concomitant disorder of both CN and LCPT is rare given the inherent differences in the biochemical properties of the immunoglobulin light chains of each disorder. We report a 64-year-old man who presented with AKI and Fanconi syndrome who was discovered to have both CN and LCPT due to the underlying disorder of monoclonal gammopathy of renal significance and who has responded favourably with conventional chemotherapy. We also review the existing literature on this interesting subject.

Rare case of post-varicella membranoproliferative glomerulonephritis presenting with massive proteinuria.

Chicken pox caused by varicella zoster virus is usually a self-limiting disease causing rare life-threatening complications. Involvement of the kidneys is infrequent during the course of the illness. Literature shows rare reports of acute glomerulonephritis following varicella infection. We report a case of 16-year-old boy presenting with anasarca with characteristic healed rashes of chicken pox. His urinalysis revealed a 'massive' nephrotic range proteinuria (16 g/24 hours), gross hematuria and pyuria. A percutaneous renal biopsy showed membranoproliferative glomerulonephritis. Most cases of post-varicella glomerulonephritis have been described in children, massive proteinuria of this range in an immunocompetent adolescent, being an extremely rare entity. Acute proliferative glomerulonephritis in such cases is usually an immune complex hypocomplementaemic glomerulonephritis in response to the zoster infection. Proteinuria in most patients is benign and self-limiting with few fatal reports of crescentic glomerulonephritis progressing to acute renal failure.