Imaging findings of IgG4-related kidney disease without extrarenal organ involvement: A case report

RATIONALE

IgG4-related disease (IgG4-RD) is a systemic chronic inflammatory disorder that can affect almost every organ. IgG4-RD includes IgG4-related kidney disease (IgG4-RKD), but lesions affecting the kidney alone or first are very rare, and a complete understanding is lacking. Computed tomography (CT) and magnetic resonance imaging (MRI) findings can show the typical characteristics of IgG4-RKD and provide information for accurate and rapid diagnosis.

PATIENT CONCERNS

We report a case of a 60-year-old woman who was admitted to our hospital for dizziness and instability while walking, her bilateral eyelids were also slightly swollen. She had no medical history.

DIAGNOSES

CT and MRI images of the patient revealed multiple local and diffuse patchy lesions in the bilateral renal parenchyma and mass-like tissue in the bilateral renal pelvis, accompanied by right hydronephrosis. A pathological examination of renal samples showed numerous lymphocyte and plasma cell infiltration. Immunohistochemistry demonstrated approximately 50% of the IgG-positive plasma cells to be IgG4+. The serum IgG level was obviously elevated, with both C3and C4 levels were reduced. The patient was diagnosed with IgG4-RKD.

INTERVENTIONS

The patient received corticosteroid therapy at another hospital.

OUTCOMES

The bilateral kidney lesions were smaller on follow-up CT images.

LESSONS

IgG4-RKD exhibits some characteristic imaging features. Despite the relatively low incidence of IgG4-RKD, it should be included in differential diagnoses when images show multiple lesions in kidneys with mild and delayed enhancement and hypointensity on T2WI in middle-aged to elderly patients.

Successful management of twin pregnancy in a woman with advanced chronic kidney disease: A case report

RATIONALE

Twin pregnancy in women with chronic kidney disease (CKD) is very rare but poses a great risk to both mother and children. In developing countries like China, advanced CKD twin pregnancies are often terminated. Here, we report a successful case and reviewed related cases, hope to facilitate further study.

PATIENT CONCERNS

A 29-year-old woman with a twin pregnancy showed serum creatinine (Scr) 100 μmol/L (CKD2) at conception. During her 12th week, Scr reached 263 μmol/L (CKD4) with urine protein 3+ and hypertension.

DIAGNOSES

Due to her pregnancy, renal biopsy was not considered. Lab tests showed deterioration of renal function and ultrasound detections showed small kidney size.

INTERVENTIONS

The patient was given basic drug therapy to control her blood pressure and supplemental nutrition without hemodialysis.

OUTCOMES

The patient delivered 2 healthy babies weighting 0.9 and 0.7 kg by cesarean section at the 28th week, but has been under maintenance hemodialysis since then.

LESSONS

Despite low birth weight and preterm delivery, successful twin pregnancies in some patients with CKD could be realized under early multidisciplinary intervention, but this poses great risks for mothers and twins, especially for patients with advanced CKD and those on hemodialysis.

Drug-encapsulated carbon (DECON): A novel platform for enhanced drug delivery

Current drug-delivery systems are designed primarily for parenteral applications and are either lipid or polymer drug conjugates. In our quest to inhibit herpes simplex virus infection via the compounds found in commonly used cosmetic products, we found that activated carbon particles inhibit infection and, in addition, substantially improve topical delivery and, hence, the efficacy of a common antiviral drug, acyclovir (ACV). Our in vitro studies demonstrate that highly porous carbon structures trapped virions, blocked infection and substantially improved efficacy when ACV was loaded onto them. Also, using murine models of corneal and genital herpes infections, we show that the topical use of drug-encapsulated carbon (DECON) reduced dosing frequency, shortened treatment duration, and exhibited higher therapeutic efficacy than currently approved topical or systemic antivirals alone. DECON is a nontoxic, cost-effective and nonimmunogenic alternative to current topical drug-delivery systems that is uniquely triggered for drug release by virus trapping.

ANCA vasculitis presenting with acute interstitial nephritis without glomerular involvement

ANCA-associated vasculitis (AAV) with renal involvement typically causes pauci-immune glomerulonephritis. We present a case of acute interstitial nephritis (AIN) as the sole renal lesion without glomerulonephritis with myeloperoxidase (MPO) AAV. A 45-year-old female with history of Crohn’s disease, gastroesophageal reflux disease (GERD) with Barrett’s esophagus, pulmonary embolism, and polyarthralgias was evaluated in nephrology clinic in 2018. AIN without glomerulonephritis was first diagnosed in 2011 on renal biopsy. p-ANCA was positive with MPO titer of > 100 U/mL. Serum creatinine improved from 2.1 to 0.9 mg/dL with prednisone and azathioprine. Repeat biopsy in 2013 for worsening renal function showed AIN without glomerular involvement. Serum creatinine improved from 1.9 to 1.2 mg/dL with prednisone and cyclosporine. Crohn’s disease was diagnosed in 2014. AIN was attributed to Crohn’s, and cyclosporine was stopped in 2016. Adalimumab was started in 2016, without improvement in renal function or urine sediment. Attempt was made to switch proton pump inhibitor (PPI) to H2-blocker, but the latter was not tolerated. Repeat biopsy in 2/2018 showed AIN with severe fibrosis and tubular atrophy and glomerulosclerosis but no active glomerular disease. MPO titers remained high at 132 U/mL. Mycophenolic acid and prednisone were started without response, followed by rituximab for AAV-associated AIN. Serum creatinine worsened to 6.0 mg/dL in 9/2018, with plan to start peritoneal dialysis. AAV may present with isolated AIN without glomerular involvement. The rarity of this presentation may contribute to delay in appropriate management. Alternative explanations for AIN, such as Crohn’s disease or PPI use should be considered with caution in the setting of high-titer ANCA positivity.

Improved neural differentiation of normal and abnormal induced pluripotent stem cell lines in the presence of valproic acid

During the generation of induced pluripotent stem cell (iPSC) lines from cord blood CD34⁺ cells, a line having complete trisomy of Chromosome 1 and deletion of q23 to qTer of Chromosome 11 was accidentally developed in our lab. The abnormality was consistently detected even at higher passages. These chromosomal anomalies are known to manifest neurological developmental defects. In order to examine if such defects occur during in vitro differentiation of the cell line, we set up a protocol for neural differentiation. Valproic acid (VPA) was earlier reported by us to enhance neural differentiation of placental mesenchymal stem cells. Here, we induced normal and abnormal iPSC lines to neural lineage with/without VPA. Neural differentiation was observed in all four sets, but for both the iPSCs lines, VPA sets performed better. The characteristics tested were morphology, neural filament length, detection of neural markers, and electrophysiology. In summary, the karyotypically abnormal line exhibited efficient neural differentiation. This iPSC line may serve as a useful tool to study abnormalities associated with trisomy 1 and deletion of q23 to qTer of Chromosome 11.

Juxta-articular tumoral calcinosis associated with the temporomandibular joint: a case report and concise review

Background

Tumoral calcinosis is an uncommon clinicopathological condition which is characterized by the formation of calcium salt deposition in intra-articular or peri-articular soft tissues. It usually presents as a focal growth of hard tissue, either solitary or multiple, beneath the skin and connective tissue. Diagnostic techniques mainly include clinical and radiographic evaluation. The most commonly involved locations include the hip, elbow, shoulder and knee. Involvement of the head and neck regions are far less common. There have been 5 case reports of temporomandibular joint involvement in the literature so far.

Case presentation

We present a case report which describes the diagnosis and management of a 59 year old female patient with chronic right temporomandibular joint pain and localized bony hard swelling over the right pre-auricular region. Patient retained normal range of motion and mouth opening. Computed tomography taken showed a radio-opaque juxta-articular ovoid mass over the right pre-auricular region in close proximity but not fused to the mandibular condyle. Surgical excision was performed for this swelling via a pre-auricular approach under general anaesthesia. Histological examination performed confirmed the diagnosis of tumoral calcinosis. Pain at the right temporomandibular joint was resolved after the surgery. Serum calcium and phosphate levels were normal in this patient.

Conclusion

Surgical excision is the primary treatment modality for tumoral calcinosis. Tumoral calcinosis may be associated with elevated serum calcium and phosphate levels. In patients with elevated serum electrolytes, it is important to consider the overall systemic health in management of this condition. Management of serum electrolytes levels plays a role in reducing recurrence rates. This case report and review aims to discuss the diagnosis, treatment and overall systemic management of this rare condition.

Circular RNA profile in liver tissue of EpCAM knockout mice

Epithelial cell adhesion molecule (EpCAM) is highly expressed during liver development and carcinogenesis, However, its functions and underlying mechanisms remain unclear. Clustered regularly interspaced short palindromic repeats (CRISPRs)/CRISPR-associated protein 9 (Cas9) technology was used in the current study to establish EpCAM^−/− mice. The expression of EpCAM in the livers of the mice at embryonic day (E)18.5 and post-natal day (P)0 was detected by immunofluorescence staining. The expression of genes associated with the development and glycogen metabolism was also assessed by reverse transcription-quantitative PCR. Additionally, the liver tissue of the EpCAM^−/− and wild-type mice was used for non-coding RNA sequencing. The results of RNA sequencing revealed 11 up-regulated and 12 downregulated circular RNAs (circRNAs). Kyoto Encyclopedia of Genes and Genomes analysis for resource genes determined that the top altered pathways included cell junctions, cell cycle, immune signaling and metabolism. This analysis was also utilized to predict the target association of the circRNA-microRNA-mRNA network. The comprehensive liver tissue circRNA expression profiles produced in the present study may help to elucidate the functions and mechanisms of EpCAM during liver development.

Resection of liposarcoma of the greater omentum: A case report and literature review

INTRODUCTION

Liposarcoma usually occurs in the retroperitoneum and limbs. Liposarcoma of the greater omentum is rare, and most information of such liposarcomas has come from case reports.

PRESENTATION OF CASE

A 60-year-old woman was found to have an 8-cm intra-abdominal mass (suspected lipoma) by computed tomography. At the age of 63 years, she underwent a medical examination and a mass was palpated in the abdomen. Contrast-enhanced computed tomography and magnetic resonance imaging confirmed the presence of a huge intra-abdominal tumor with the omental artery passing through the mass. The tumor was simply resected. Histopathologically, the tumor was diagnosed as a well-differentiated liposarcoma, and the resection margin was microscopically negative. The patient had developed no recurrence or complications 9 months postoperatively.

DISCUSSION

Liposarcoma of the greater omentum is rare, and differentiation of liposarcoma from other tumors is challenging. Adjuvant therapy has not been established as an effective treatment, and radical (R0) resection of the tumor is recommended. Our case of liposarcoma of the greater omentum was surgically managed with good outcomes.

CONCLUSION

The diagnosis of liposarcoma with a lipomatous tumor is challenging, and resection should be considered for huge intra-abdominal lipomatous tumors.

Combination of Renal Angioplasty and Angiotensin-converting-enzyme Inhibitor Can Reduce Proteinuria in Patients with Bilateral Renal Artery Disease

Recent large clinical trials failed to show clear benefits of percutaneous transluminal renal angioplasty (PTRA) as compared with medical therapy on patients with renal artery stenosis. It was also reported that proteinuria is an adverse prognostic factor after PTRA, and PTRA is less effective in patients with overt proteinuria. From the renoprotective point of view, to reduce proteinuria after PTRA is an important therapeutic goal in patients with renal artery stenosis with overt proteinuria. We hereby describe two patients successfully treated by combination therapy with PTRA and administration of angiotensin-converting enzyme (ACE) inhibitor for bilateral renal artery disease with overt proteinuria.

Clinical features of hypermagnesemia in patients with functional constipation taking daily magnesium oxide

Although magnesium oxide is widely used as a laxative, alterations in serum magnesium concentrations among patients taking daily magnesium oxide have not been clarified. The present retrospective, cross-sectional study investigated the risk factors for hypermagnesemia in patients taking daily oral magnesium oxide. Of 2,176 patients administered daily magnesium oxide, 193 (8.9%) underwent assays of serum magnesium concentrations and were evaluated. High serum magnesium concentration and hypermagnesemia were defined as serum magnesium concentrations ≥2.5 mg/dl and ≥3.0 mg/dl, respectively. Of the 193 patients taking daily magnesium oxide, 32 (16.6%) had high serum magnesium concentration and 10 (5.2%) had hypermagnesemia. Factors associated with hypermagnesemia included chronic kidney disease (CKD) grade 4 (p = 0.014) and magnesium oxide dosage (p = 0.009). Factors associated with high serum magnesium concentration included magnesium oxide dosage >1,000 mg/day (p = 0.004), CKD grades 4 (p = 0.000) and concomitant use of stimulant laxatives (p = 0.035). Age, however, was not associated with hypermagnesemia or high serum magnesium concentration. In conclusion, renal function and magnesium oxide dosage, but not age, were associated with hypermagnesemia and high serum magnesium concentration in patients with functional constipation taking daily magnesium oxide.

Type I cryoglobulinemic vasulitis with eosinophilia: A case report and literature review

RATIONALE

Type I monoclonal cryoglobulinemia is usually associated with lymphoproliferative disorders, such as monoclonal gammopathy of undetermined significance (MGUS), myeloma, chronic lymphocytic leukemia (CLL) and lymphoplasmocytic lymphoma (LPL). Clinical symptoms related to Type I cryoglobulin (CG) isotype often include skin, neurological and renal manifestations.

PATIENT CONCERNS

A 42-year-old woman who initially presented urticaria, palpable purpura in both her upper extremities and legs, eosinophilia and Raynaud phenomenon. Skin biopsy revealed eosinophil infiltration. Monoclonal immunoglobulin (Ig) G-κprotein was detected and CG was also positive.

DIAGNOSES

The patient was finally diagnosed as MGUS related Type I CG.

INTERVENTIONS

Cyclophosphamide-dexamethasone-thalidomide (CDT) therapy was initiated.

OUTCOMES

The treatment relieved the skin symptoms efficiently.

LESSONS

To our knowledge, this is a rare case of Type I cryoglobulinemic vasulitis with eosinophilia complicated by MGUS, and the effective treatment of cyclophosphamide combined with thalidomide and prednisone may provide a new therapeutic option for cryoglobulinemic vasulitis.

Small-cell lung cancer with Mallory-Weiss syndrome as the prominent manifestation

The presence of Mallory-Weiss syndrome (MWS) in patients with small-cell lung cancer (SCLC) is uncommon. MWS is characterized by longitudinal superficial mucosal laceration at the esophagogastric junction and can be caused by a variety of causes, with upper digestive tract hemorrhage as the primary manifestation. SCLC is the most invasive histological subtype of lung cancer, and approximately a quarter of all SCLC patients undergo paraneoplastic syndrome of inappropriate antidiuretic hormone secretion, such as hyponatremia. In this study, we report a case of MWS in a middle-aged patient who was diagnosed with SCLC associated with hyponatremia. Clinicians should be alerted of the presence of MWS in upper gastrointestinal bleeding, such as epigastric pain, hematemesis, or melena, and keep SCLC in mind as a potential cause for underlying disease identification.

Renal Pathologic Findings in TAFRO Syndrome: Is There a Continuum Between Thrombotic Microangiopathy and Membranoproliferative Glomerulonephritis? A Case Report and Literature Review

Background: TAFRO syndrome is a clinical subtype of idiopathic multicentric Castleman disease (iMCD) that is characterized by thrombocytopenia, anasarca, fever and/or elevated serum C-reactive protein, renal dysfunction, and organomegaly.

Case Presentation: A 28-year-old woman with fever, weight gain of 13 kgs, lower extremity edema, hepatosplenomegaly, and multicentric peripheral lymphadenopathy was referred to our center. Laboratory investigations revealed anemia, thrombocytopenia, creatinine at 1.19 mg/dL and hypoalbuminemia at 33 g/L. Proteinuria was measured at 2 g/day including albuminuria at 1.5 g/day. Urinary sediment examination found leukocyturia at 44,000/mL and hematuria at 645,000/mL. Vascular endothelial growth factor (VEGF) level was elevated. A cervical lymph node biopsy found features consistent with the mixed histopathological subtype of iMCD. A renal biopsy revealed a membranoproliferative glomerulonephritis (MPGN) pattern. We initiated 3 days of methylprednisolone pulse-therapy at 1,000 mg per day, followed by prednisone 1 mg/kg/day and evolution was favorable.

Review of Literature: 19 iMCD patients with TAFRO syndrome had undergone a renal biopsy: 8 cases with author's diagnosis consistent with MPGN-like and 11 cases of thrombotic microangiopathy (TMA)-like glomerulopathy without fibrin thrombi in glomerular capillaries or arterioles and without typical biological signs. Clinical, biological, and outcome characteristics were similar between the cases described as having MPGN and TMA-like presentation. After a thorough review of histopathological descriptions for each case, MPGN lesions seems to be the consequences of chronic glomerular endothelial injury in persistent TMA. We suspect that VEGF and IL-6 play a key role in the physiopathology of the spectrum of renal involvement from TMA-like to MPGN observed in TAFRO syndrome.

Conclusion: We present a Caucasian iMCD patient with TAFRO syndrome with renal insufficiency secondary to MPGN, which might be secondary to a chronic TMA-like disease. We suspect that there is a continuum between TMA and MPGN lesions in TAFRO syndrome favored by VEGF and IL-6.

Novel heterozygous missense mutation of SLC12A3 gene in Gitelman syndrome: A case report

BACKGROUND

To screen for possible pathogenic loci in a patient with Gitelman syndrome by high-throughput exome sequencing and to explore the relationship between genotype and phenotype.

CASE SUMMARY

The clinical data of the patient were collected. Peripheral blood samples were obtained to isolate white blood cells and extract genomic DNA. High-throughput whole exome sequencing for candidate pathogenic genes in the proband was completed by the Huada Gene Technology Co. Ltd (Shenzhen, China). Sequencing showed a novel heterozygous missense mutation (a G to A transition at nucleotide 2582) in exon 22 of the SLC12A3 gene, which resulted in a substitution of histidine for arginine at position 816 of the LRP1B protein and caused the occurrence of disease.

CONCLUSION

This is the first report of a new pathogenic mutation in SLC12A3. Further functional studies are particularly necessary to explore potential molecular mechanisms.

Rupture of an Infected Renal Cyst Secondary to a Renocolic Fistula in Autosomal Dominant Polycystic Kidney Disease

We present a rare case of retroperitoneal rupture of an infected renal cyst secondary to a renocolic fistula in a patient with autosomal dominant polycystic kidney disease (ADPKD). Intraperitoneal rupture of infected cysts in ADPKD resulting in peritonitis has been described, but to our knowledge, this is the first reported case of retroperitoneal rupture. Cyst infections are a common complication of ADPKD and are difficult to treat, potentially leading to sepsis and death.

Arteriovenous fistula-related renal bleeding 5 days after percutaneous renal biopsy

A 32-year-old Japanese woman was admitted to our hospital for evaluation of microscopic hematuria with a positive family history. Percutaneous renal biopsy was performed under real-time ultrasound guidance using a 16-gauge automated needle and three specimens were obtained. She had no risk factors for hemorrhage. However, macroscopic hematuria developed from 5 days after biopsy and persisted for 4 days. Her Hb decreased markedly from 15.0 to 8.1 g/dL. Enhanced computed tomography revealed urinary tract hematoma, while the early arterial phase showed inflow of contrast medium into the left renal vein from a pseudoaneurysm on a branch left renal artery. Renal transcatheter arterial embolization was performed using platinum microcoils and the arteriovenous fistula was occluded. The patient did not require blood transfusion. Severe renal bleeding that causes urinary tract hematoma usually occurs within 24 h after renal biopsy, but the possibility of late-onset renal bleeding should be kept in mind.

Acute Kidney Injury Associated With Human Granulocytic Anaplasmosis: A Case Report

Tick-borne illnesses are a growing problem in the United States. Human granulocytic anaplasmosis (HGA), carried by the Ixodes scapularis tick, is caused by Anaplasma phagocytophilum. While the clinical manifestations of HGA may be protean, ranging from asymptomatic infection to life-threatening multiorgan failure, renal involvement is uncommon. We report a case of a 64-year-old man presenting with a febrile illness and acute nephritis in the setting of HGA infection. The patient's kidney biopsy was characterized by a membranoproliferative glomerulonephritis pattern and acute interstitial inflammation. After appropriate antibiotic treatment and high-dose steroids, the patient had a marked improvement in kidney function, although a subsequent recrudescence of nephritis required a 6-month course of additional steroids. As the prevalence of tick-borne diseases continues to spread across the United States, raising awareness of the potential for atypical presentations is important, particularly because early diagnosis and treatment can be curative and prevent further complications.

Clinical outcome of HCV-associated cryoglobulinemic glomerulonephritis following treatment with direct acting antiviral agents: a case-based review

Newer treatment protocols involving direct-acting antiviral agents (DAAs) have been associated with high rates of sustained virologic response (SVR) and clinical remission in patients with hepatitis C virus (HCV) associated cryoglobulinemic vasculitis (HCV-CV), but clinical response in those with renal involvement is less clear. Our goal was to evaluate the clinical course following DAA therapy in one of the largest cohorts of patients with HCV-associated cryoglobulinemic glomerulonephritis (HCV-GN) reported to date. This is an observational study of patients with chronic HCV infection and circulating cryoglobulins (CC) treated with DAAs in our department from January 2015 to January 2019. We identified a total of 67 patients with HCV and CC out of which nine patients fulfilled the criteria of HCV-GN and had adequate clinical follow-up time. We describe a cohort of nine patients with a mean age of 57 years and known duration of HCV infection ranging 3-20 years (four with evidence of compensated cirrhosis). All patients received the ritonavir-boosted paritaprevir/ombitasvir/dasabuvir regimen for 12 weeks and achieved SVR without subsequent viral relapse. Following DAAs completion, one patient developed "new-onset" cryoglobulinemic glomerulonephritis, six showed either persistent or worsening glomerulonephritis, and only two patients had a complete clinical response (CCR). Of the six patients with either persistent or worsening CV, 67% received additional immunosuppressive (IS) therapy for uncontrolled CV. Of the two patients that had a CCR, one patient received prior IS therapy while the other one improved without any additional intervention. Newer HCV treatment protocols involving DAAs are highly successful in eradication of HCV infection; however, in our experience, DAA treatment alone is insufficient in improving the renal outcomes of patients with HCV-GN and additional IS therapies should be considered.

Catheterization in a patient with end-stage renal disease through persistent left superior vena cava: a rare case report and literature review

Background

Persistent left superior vena cava (PLSVC) is a common vena cava malformation, and drains blood into the right atrium via the dilated coronary sinus in most cases. It is usually asymptomatic and detected incidentally during invasive procedures or imaging. Whether the hemodialysis catheters can be placed in PLSVC is still controversial now (Stylianou et al. Hemodial Int 11:42-45, 2007).

Case presentation

Here we report a rare case of catheterization through PLSVC in an end-stage renal disease (ESRD) male patient whose PLSVC connected with pulmonary vein with insufficient blood flow eventually. Among the other 28 cases included in the literature review, 16 cases were non-tunneled catheter and 12 cases were cuffed, tunneled catheter and most of them could provide adequate blood flow.

Conclusion

PLSVC is a rare malformation and mostly asymptotic, we believe that PLSVC drains blood into the right atrium with enough inner diameter and blood flow can serve as an alternative site for conventional dialysis access. However, the feasibility of hemodialysis catheterization through it and measures to avoid serious complications are still needed to be discussed.

Intravascular cardiac lipoproteinosis: extrarenal manifestation of lipoprotein glomerulopathy

Intracapillary lipoprotein thrombi are a distinct histopathologic finding described in the setting of lipoprotein glomerulopathy. The disease is associated with mutations in the apolipoprotein E gene and responds well to lipid-lowering treatments. Lipoprotein glomerulopathy is thought to primarily affect the kidneys, and lipoprotein thrombi have never been described in any other organ. Herein we present the first recognized case with extrarenal manifestations in the form of intravascular cardiac lipoprotein deposition.

A Case of Severe Acute Kidney Injury Exacerbated by Canagliflozin in a Patient with Type 2 Diabetes

BACKGROUND

Sodium glucose cotransport (SGLT)-2 inhibitors are the newest class of antihyperglycemic agents used as second- or third-line treatment in the management of type 2 diabetes. Although the use of SGLT-2 inhibitors has not been shown to cause nephrotoxicity, there have been case reports of SGLT-2 inhibitor use being associated with acute kidney injury.

CASE PRESENTATION

A 72-year-old woman with a history of type 2 diabetes and no known chronic renal insufficiency presented to the emergency room with a 3-day history of nausea, vomiting, and increased somnolence. She was found to have potassium level of 7.4 (normal: 3.5-5.5) mmol/L and a markedly elevated creatinine level at 1154 (normal: 45-95) μmol/L. Imaging of the abdomen and pelvis did not reveal any findings of obstruction. Urine microscopy showed many granular casts. In the absence of other causes for her clinical presentation, the patient was diagnosed with acute kidney injury secondary to ischemic acute tubular necrosis, with canagliflozin use likely an important contributing factor.

CONCLUSIONS

Physicians should inform patients to stop the use of SGLT-2 inhibitors when patients are unable to maintain hydration or during acute illness. Use of SGLT-2 inhibitors in managing type 2 diabetes should be done with caution among more vulnerable populations, including individuals with cognitive impairment and the elderly.

Clinical time course and CT detection of metastatic disease to the small bowel

PURPOSE

The purpose of this study was to identify the CT characteristics of metastatic disease of the small bowel and define the clinical time course between primary tumor diagnosis and small bowel metastasis detection.

METHODS

A retrospective search of a pathologic database for metastases to small bowel identified 242 cases. Exclusion criteria were cases without CT (N = 49), serosal or mesenteric metastases (N = 114), or cases of direct invasion to small bowel (N = 63). The clinical records and imaging were reviewed for 16 patients.

RESULTS

Melanoma was the most common malignancy to metastasize to small bowel (7 of 16 patients). Only one of the 16 cases was detected at the time of initial diagnosis of their primary malignancy. The average time from diagnosis of the primary malignancy or remission to the time of detection of the small bowel metastasis was 7.2 and 8.3 years, respectively. The most common symptoms were gastrointestinal bleeding (N = 5) and small bowel obstruction (N = 5). In 3 cases, the masses were not identified on pre-operative CT.

CONCLUSION

Metastases to the small bowel often occur many years after the initial diagnosis of the primary malignancy or entering remission and may be symptomatic. Attention to the small bowel is particularly important in melanoma patients, who may have multiple small bowel metastases, even after many years of being disease free. As oncology patients undergo numerous surveillance scans and improved therapies allow for longer survival, detection of these masses at a small size can facilitate elective resection to avert urgent surgical intervention.

A Reversible Gastric Uptake of Bone Scintigraphy in a Patient with Hypercalcemia

Hypercalcemia is a severe complication in cases of vitamin D intoxication that can result in metastatic calcification. We herein report a female case with hypercalcemia due to eldecalcitol administration associated with the increased uptake of technetium-99m hydroxymethylene diphosphonate (^99mTc-HMDP) as the bone-scanning agent in the stomach. A histologic assessment using biopsy specimens identified metastatic calcification of the stomach. After the normalization of serum calcium levels, the gastric uptake of ^99mTc-HMDP disappeared. This case indicates the usefulness of bone scintigraphy with ^99mTc-HMDP to detect visceral metastatic calcification and to monitor its therapeutic effects in patients with hypercalcemia.

Genotype-phenotype correlation and prognostic impact in Chinese patients with Alport Syndrome

BACKGROUND

Alport Syndrome (AS) is a progressive hereditary glomerular disease. It is often accompanied by sensorineural hearing loss and ocular abnormalities and can sometimes develop into end stage renal disease (ESRD), which is caused by mutations in the genes encoding the collagen type IV family of proteins.

METHODS

This study analyzed the association between the clinical data of seven AS families and genes and the disease progression of different mutation types, including COL4A3 (OMIM 120070)，COL4A4 (OMIM 120131), and COL4A5 (OMIM303630).

RESULTS

A total of six new pathogenic mutation sites, one complex heterozygous mutation at COL4A3, and a combined mutation of COL4A5 and INF2 (OMIM 610982) were identified in this study. It was revealed that the clinical manifestations of X-linked AS caused by mutations in the COL4A5 gene were more severe in males than in females. In addition, the difference in patient phenotype can be attributed to the location of gene mutations affecting the protein domain or functional domain. Our data suggested that the gene deletion and nonsense mutations had a high risk for progression to ESRD.

CONCLUSION

Our results revealed the spectrum of type IV collagen genes, which contribute to the enrichment of database resources and has important implications in the diagnosis, prognosis, and guiding treatment of AS.

Clinical courses and complications of young adults with Autosomal Recessive Polycystic Kidney Disease (ARPKD)

Autosomal recessive polycystic kidney disease (ARPKD) is a severe pediatric hepatorenal disorder with pronounced phenotypic variability. A substantial number of patients with early diagnosis reaches adulthood and some patients are not diagnosed until adulthood. Yet, clinical knowledge about adult ARPKD patients is scarce. Here, we describe forty-nine patients with longitudinal follow-up into young adulthood that were identified in the international ARPKD cohort study ARegPKD. Forty-five patients were evaluated in a cross-sectional analysis at a mean age of 21.4 (±3.3) years describing hepatorenal findings. Renal function of native kidneys was within CKD stages 1 to 3 in more than 50% of the patients. Symptoms of hepatic involvement were frequently detected. Fourteen (31%) patients had undergone kidney transplantation and six patients (13%) had undergone liver transplantation or combined liver and kidney transplantation prior to the visit revealing a wide variability of clinical courses. Hepatorenal involvement and preceding complications in other organs were also evaluated in a time-to-event analysis. In summary, we characterize the broad clinical spectrum of young adult ARPKD patients. Importantly, many patients have a stable renal and hepatic situation in young adulthood. ARPKD should also be considered as a differential diagnosis in young adults with fibrocystic hepatorenal disease.

Next-Generation-Sequencing-Based Hospital Outbreak Investigation Yields Insight into Klebsiella aerogenes Population Structure and Determinants of Carbapenem Resistance and Pathogenicity

Klebsiella aerogenes is a nosocomial pathogen associated with drug resistance and outbreaks in intensive care units. In a 5-month period in 2017, we experienced an increased incidence of cultures for carbapenem-resistant K. aerogenes (CR-KA) from an adult cardiothoracic intensive care unit (CICU) involving 15 patients. Phylogenomic analysis following whole-genome sequencing (WGS) identified the outbreak CR-KA isolates to group together as a tight monoclonal cluster (with no more than six single nucleotide polymorphisms [SNPs]), suggestive of a protracted intraward transmission event. No clonal relationships were identified between the CICU CR-KA strains and additional hospital CR-KA patient isolates from different wards and/or previous years. Carbapenemase-encoding genes and drug-resistant plasmids were absent in the outbreak strains, and carbapenem resistance was attributed to mutations impacting AmpD activity and membrane permeability. The CICU outbreak strains harbored an integrative conjugative element (ICE) which has been associated with pathogenic Klebsiella pneumoniae lineages (ICEKp10). Comparative genomics with global K. aerogenes genomes showed our outbreak strains to group closely with global sequence type 4 (ST4) strains, which, along with ST93, likely represent dominant K. aerogenes lineages associated with human infections. For poorly characterized pathogens, scaling analyses to include sequenced genomes from public databases offer the opportunity to identify emerging trends and dominant clones associated with specific attributes, syndromes, and geographical locations.

Renal sarcoidosis: approach to diagnosis and management

PURPOSE OF REVIEW

The purpose of this article is to provide understanding of renal sarcoidosis, the different types of renal sarcoidosis, disease burden of renal involvement, and treatment options.

RECENT FINDINGS

The frequency of renal involvement seems to be underestimated, but renal sarcoidosis represents a relevant group of organ manifestations and significantly adds to the patient's morbidity. Because histopathological analysis of renal biopsy specimens can reveal various entities, a diagnostic workup is necessary in every patient with sarcoidosis.

SUMMARY

If systematically screened for renal manifestations are likely to occur in up to 25-30% of all sarcoidosis patients. The most common histological form of renal sarcoidosis is the granulomatous interstitial nephritis; however, granulomas can be absent. Furthermore, one can find various forms of secondary glomerulonephritis. In cases with dysregulated calcium homeostasis, nephrocalcinosis and nephrolithiasis are commonly detectable kidney diseases. AA amyloidosis or renal masses because of granuloma formation are considered to be rare manifestations. In addition to glucocorticoids various immunosuppressive treatments such as tumor necrosis factor alpha inhibitors have proven to be effective based on case series.

Pathological findings of progressive renal involvement in a patient with TAFRO syndrome

TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly) is thought of as an atypical type of idiopathic multicentric Castleman's disease. Interleukin-6, vascular endothelial growth factor (VEGF), and other cytokines are considered etiological factors. A 45-year-old woman was admitted to hospital with unknown fever and abdominal pain. She had thrombocytopenia, anasarca, proteinuria/hematuria, and slight hepatosplenomegaly. Based on her clinical course and laboratory data, she was diagnosed as having TAFRO syndrome. Kidney biopsy showed a membranoproliferative glomerulonephritis (MPGN)-like lesion containing lobulations of glomeruli, endothelial cell swelling, double contours of the glomerular basement membrane, and mesangiolysis. She was treated with methylprednisolone pulse (500 mg/day) and oral prednisolone (60 mg/day) therapy. The pleural effusion and ascites disappeared, and renal function normalized. Cyclosporine was added to prevent relapse. She went home, with no relapse 8 months after hospitalization. MPGN-like lesions were found frequently in patients with TAFRO syndrome in recent reports. However, there are few reports of pathologically confirmed cases of progressive renal involvement in TAFRO syndrome. The relationship between VEGF expression in renal tissue and the pathogenesis of renal injury in TAFRO syndrome was investigated in the present case.

Report of Another Mutation Proven Case of Carbonic Anhydrase II Deficiency

Carbonic anhydrase (CA) II deficiency results in an uncommon type of autosomal recessive sclerosing bone dysplasia with renal tubular acidosis and intracerebral calcification. We report a classic case of CA II-associated osteopetrosis with a previously reported homozygous frameshift mutation. Child was evaluated for short stature and failure to thrive. He was diagnosed as osteopetrosis in view of the presence of hepatosplenomegaly and increased bone density though hematological parameters were normal. Further evaluation showed presence of associated distal renal tubular acidosis raising a possibility of CA II deficiency. Mutation analysis revealed a previously reported homozygous frameshift mutation c.143-146delCTGT (p.Ser48Phefs*9) in CA2. Child has normal growth after initiation of alkali therapy.

Tubular Injury and Dendritic Cell Activation Are Integral Components of Light Chain-Associated Acute Tubulointerstitial Nephritis

CONTEXT.—

Light chain-associated acute tubulointerstitial nephritis (LC-ATIN) is a variant of light chain proximal tubulopathy (LCPT). It is characterized by interstitial inflammation with tubulitis and deposition of monoclonal light chains in the tubulointerstitium. LC-ATIN is a rather poorly recognized pattern of LCPT and not much is known about this entity.

OBJECTIVE.—

To determine the clinicopathologic features of patients with LC-ATIN and investigate the proximal tubular injury and mechanism of interstitial inflammation in LC-ATIN.

DESIGN.—

A total of 38 cases of LC-ATIN were identified from the archives of 5043 renal biopsy specimens. In all cases, routine light microscopic examination, immunofluorescence, and electron microscopic examination were performed. In selected cases, immunofluorescent staining of dendritic cells and immunohistochemical staining for 4 tubular injury markers-KIM-1, p53, bcl-2, and Ki-67-were performed.

RESULTS.—

A characteristic finding in LC-ATIN cases was immunofluorescence staining of monoclonal light chains along tubular basement membranes in linear fashion and inside proximal tubular cells with a granular pattern. No monoclonal light chains were present in glomerular or vascular compartments confirmed with immunofluorescence, electron microscopy, and ultrastructural gold labeling. Ten of 15 LC-ATIN cases (67%) were concurrently positive for the 4 tubular injury markers. Dendritic cells were identified within the tubulointerstitium in the renal biopsy specimens, interacting with surrounding tubules with light-chain deposits and inflammatory cells.

CONCLUSIONS.—

Significant proximal tubular injury occurs associated with LC-ATIN, and the monoclonal light chains accumulated in proximal tubular cells contribute to the injury. Dendritic cells are involved in the pathogenesis of interstitial inflammation in LC-ATIN.

Daily Sodium Monitoring and Fluid Intake Protocol: Preventing Recurrent Hospitalization in Adipsic Diabetes Insipidus

Management of diabetes insipidus (DI) is usually facilitated by an intact thirst mechanism prompting water ingestion in times of rising osmolality. Maintenance of eunatremia can be quite difficult in patients with DI and adipsia because of the absence of this homeostatic mechanism. Few published protocols for management of these complex cases exist. We report a case of a 16-year-old girl who had a diagnosis of craniopharyngioma with preoperative hypopituitarism and central DI. She underwent transsphenoidal resection in 2013 and additionally developed postoperative cognitive impairment and hypothalamic dysfunction, including adipsia. She subsequently experienced widely dysregulated sodium levels, necessitating inpatient care ∼30% of days in 2014 and 2015. We created a protocol for this patient that uses a fixed daily dose of subcutaneous DDAVP combined with daily modulation of fluid intake based on daily serum sodium measurement. The protocol provides guidance for the day's fluid intake based on both the current sodium result and the rate of change from the previous day. Since the adoption of the protocol in June 2016, the patient has had a dramatic reduction in hospitalizations. Use of a protocol for providing recommendations for fluid intake based on the sodium level and rate of change may help to maintain normal sodium levels in such patients, decreasing hospitalization and improving quality of life.

Distal renal tubular acidosis and severe hypokalemia: a case report and review of the literature

Background

Distal renal tubular acidosis is a relatively infrequent condition with complex pathophysiology that can present with life-threatening electrolyte abnormalities.

Case presentation

We describe a case of a 57-year-old Caucasian woman with previous episodes of hypokalemia, severe muscle weakness, and fatigue. Upon further questioning, symptoms of dry eye and dry mouth became evident. Initial evaluation revealed hyperchloremic metabolic acidosis, severe hypokalemia, persistent alkaline urine, and a positive urinary anion gap, suggestive of distal renal tubular acidosis. Additional laboratory workup and renal biopsy led to the diagnosis of primary Sjögren’s syndrome with associated acute tubulointerstitial nephritis. After potassium and bicarbonate supplementation, immunomodulatory therapy with hydroxychloroquine, azathioprine, and prednisone was started. Nonetheless, her renal function failed to improve and remained steady with an estimated glomerular filtration rate of 42 ml/min/1.73 m². The literature on this topic was reviewed.

Conclusions

Cases of renal tubular acidosis should be carefully evaluated to prevent adverse complications, uncover a potentially treatable condition, and prevent the progression to chronic kidney disease. Repeated episodes of unexplained hypokalemia could be an important clue for diagnosis.

Coagulation Pathways in Neurological Diseases: Multiple Sclerosis

Significant progress has been made in understanding the complex interactions between the coagulation system and inflammation and autoimmunity. Increased blood-brain-barrier (BBB) permeability, a key event in the pathophysiology of multiple sclerosis (MS), leads to the irruption into the central nervous system of blood components that include virtually all coagulation/hemostasis factors. Besides their cytotoxic deposition and role as a possible trigger of the coagulation cascade, hemostasis components cause inflammatory response and immune activation, sustaining neurodegenerative events in MS. Early studies showing the contribution of altered hemostasis in the complex pathophysiology of MS have been strengthened by recent studies using methodologies that permitted deeper investigation. Fibrin(ogen), an abundant protein in plasma, has been identified as a key contributor to neuroinflammation. Perturbed fibrinolysis was found to be a hallmark of progressive MS with abundant cortical fibrin(ogen) deposition. The immune-modulatory function of the intrinsic coagulation pathway still remains to be elucidated in MS. New molecular details in key hemostasis components participating in MS pathophysiology, and particularly involved in inflammatory and immune responses, could favor the development of novel therapeutic targets to ameliorate the evolution of MS. This review article introduces essential information on coagulation factors, inhibitors, and the fibrinolytic pathway, and highlights key aspects of their involvement in the immune system and inflammatory response. It discusses how hemostasis components are (dys)regulated in MS, and summarizes histopathological post-mortem human brain evidence, as well as cerebrospinal fluid, plasma, and serum studies of hemostasis and fibrinolytic pathways in MS. Studies of disease-modifying treatments as potential modifiers of coagulation factor levels, and case reports of autoimmunity affecting hemostasis in MS are also discussed.

Genetic Determinants of IgA Nephropathy: Western Perspective

IgA nephropathy (IgAN) represents a genetically complex multifactorial trait. Its prevalence and clinical features vary geographically, and the disease has a range of clinical presentations that suggest multiple subtypes. Although familial aggregation of IgAN has been reported and prior linkage studies have highlighted significant locus heterogeneity, specific genetic variants underlying familial IgAN have not yet been defined. Population-based genome-wide association studies (GWAS) have discovered nearly 20 IgAN risk loci, providing novel insights into disease epidemiology and molecular mechanisms, shifting old paradigms of the disease pathogenesis. Follow-up fine-mapping studies have identified specific causal variants, and genotype-phenotype correlation studies have begun to delineate clinical consequences of GWAS risk alleles. The association between IgAN and galactose-deficient IgA1 (Gd-IgA1), a validated serum biomarker of IgAN, presented another avenue for genetic discovery because elevated serum levels of Gd-IgA1 are highly heritable. Recent GWAS for serum Gd-IgA1 levels provided novel insights into genetic regulation of this trait, but the genetic link between Gd-IgA1 and IgAN has not yet been established. In this review, we discuss these developments in the broader context of modern genetic approaches to complex traits, and provide our perspective on the critical challenges that need to be addressed to advance the field.

Outcomes with acyclovir treatment in herpes simplex encephalitis after surgery for solid CNS tumors: a case report and systematic review of the literature

Background

Herpes simplex encephalitis (HSE) occurring within 30 days after neurosurgery for solid CNS tumors is underrecognized and underreported but remains important because of high morbidity and mortality. We present the case of a 41-year-old woman who had HSE after craniopharyngioma surgery, and delayed recognition and treatment led to a poor outcome. Subsequently, we review reported HSE cases after neurosurgery for solid CNS tumors and describe outcomes after treatment with and without acyclovir.

Methods

A literature search was performed for cases meeting the above criteria. Information was gathered regarding patient demographics, tumor types, symptoms, diagnostic workup, therapy, and outcomes.

Results

Eighteen cases were studied. Encephalopathy, fever, and seizures were the most common symptoms. A majority of patients (78%) received IV acyclovir, with a 79% survival rate with treatment. Mortality rate was 100% in untreated cases. The median time to starting acyclovir was 17 postoperative days (range, 8-53 days). Most patients received steroids, but its use was not associated with a specific outcome.

Conclusions

HSE may develop following neurosurgical resection, and the threshold for suspicion of this condition should be extremely low in a patient who shows compatible symptoms (encephalopathy, fever, or seizures) or does not recover as planned. Moreover, in case of suspicion of HSE, acyclovir should be promptly started until infection can be definitely ruled out. A delay in diagnosis of HSE and failure to treat may result in severe morbidity as well as mortality. This observation may warrant further study.

Multiple Faces of Chronic Lymphocytic Leukaemia: A Patient with Renal, Cardiac, and Skeletal Complications

We describe a patient who had chronic lymphocytic leukaemia (CLL) Binet stage A at presentation with further evidence of disease at multiple sites but who initially required no treatment. However, several years later, her peripheral blood lymphocyte count started to increase, and soon after that she suffered an acute myocardial infarct (in the absence of coronary atheroma) together with proteinuric renal failure due to membranoproliferative glomerulonephritis. Her renal function improved markedly following anti-CLL chemotherapy. We postulate that her cardiac and renal disease were both complications of her CLL. In patients with CLL who develop new clinical signs or symptoms (even if apparently unrelated), consideration should be given as to whether these may be disease complications as this may serve as an indication to commence anti-CLL therapy; close liaison between different specialties is vital.

[18F-FDG positron emission tomography in non-oncological renal pathology: Current indications and perspectives]

Positron emission tomography combined with computed tomography (PET/CT) is a nuclear imaging technique which provides anatomical and functional information. PET/CT is increasingly used in non-oncological nephrology since conventional radiological approaches after injection of contrast agents are relatively contra-indicated in patients with chronic kidney disease (CKD). PET/CT after i.v. injection of ¹⁸F-fluoro-deoxy-glucose (FDG) is not toxic and is characterized by a high sensitivity. The level of irradiation (∼5mSv) is acceptable. CKD does not significantly influence tissue uptake of ¹⁸F-FDG. The purpose of the present review aims at detailing the non-oncological indications of ¹⁸F-FDG PET/CT in general nephrology and after kidney transplantation. Particularly, ¹⁸F-FDG PET/CT appears useful in the diagnosis of cyst infection in patients with autosomal dominant polycystic kidney disease, as well as in the characterization of retroperitoneal fibrosis. In kidney transplant recipients, ¹⁸F-FDG PET/CT may help in the diagnostic work-up of suspected acute rejection, thereby eventually avoiding unnecessary kidney transplant biopsy. Perspectives in ¹⁸F-FDG PET/CT imaging are discussed, including innovative approaches of image analysis.

Adult IgA vasculitis (Henoch-Schönlein purpura)

IgA vasculitis is a systemic vasculitis affecting small vessels. IgA vasculitis usually affect children whereas it is rare in adults (150 to 200 for 1) in which the disease is often more serious with more frequent and severe nephritis. Prevalence of adult IgA vasculitis is unknown and its annual incidence is 1 in 1 million. The dominant clinical features include cutaneous purpura, arthritis and gastrointestinal symptoms. Sometimes nephritis can add, typically as glomerulonephritis with IgA mesangial deposits. Pulmonary, cardiac, genital and neurological symptoms have also been observed. Although the cause is unknown, it is clear that IgA plays a pivotal role in the immunopathogenesis of IgA vasculitis. Only symptomatic treatment is advised in case of self-limited disease. Treatment of severe IgA vasculitis, nephritis or gastrointestinal manifestations, is not established but some studies, which need to be confirmed, reported the benefit of corticosteroids combined with immunosuppressive drugs. Short-term outcome depends of the severity of the gastro-intestinal manifestations. The long-term prognosis is heavily dependent on the presence and severity of nephritis. Studies with prolonged follow-up show up to one third of adult patients reaching end stage renal failure, as for IgA nephropathy. Some authors even suggest that IgA nephropathy and IgA vasculitis would be the same disease.

Collapsing glomerulopathy in older adults

Collapsing glomerulopathy has been described in settings of viral infections, drug, genetic, ischemic, renal transplant, and idiopathic conditions. It has a worse prognosis than other morphologic variants of focal segmental glomerulosclerosis, and may be treated with aggressive immunosuppression. In this study, we sought to characterize the clinical and morphologic findings in older adults with collapsing glomerulopathy. Renal biopsies and associated clinical data from patients aged 65 or older with a diagnosis of collapsing glomerulopathy were retrospectively reviewed at 3 academic institutions. Patients (n = 41, 61% male, median age 71) usually had hypertension (88%), nephrotic range proteinuria (91%), and renal insufficiency (median serum creatinine 2.5 mg/dL). A likely precipitating drug (5%) or vascular procedure (5%) was identified in a minority of cases; viral infections were infrequent. Renal biopsies contained a median of 40% globally and 16% segmentally sclerotic glomeruli. Approximately 60% of cases had moderate or severe arteriosclerosis, arteriolar hyalinosis, and/or tubular atrophy and interstitial fibrosis; 7% had atheroembolic disease and 5% had thrombotic microangiopathy. In 28 patients with available follow-up information, eight (19%) were treated with immunosuppressives, which were not tolerated by 2. At a median interval of 14 months, 5 (18%) patients had died, 12 (43%) had end stage renal disease, and 12 were alive with renal insufficiency and proteinuria. Treatment with immunosuppressive therapy did not have a significant benefit with regard to the primary outcome of overall or renal survival. One steroid-treated patient with diabetes died 6 weeks after biopsy, with invasive rhinoorbital Rhizopus infection. In conclusion, collapsing glomerulopathy in older patients is usually not associated with viral infections, and is accompanied by significant chronic injury in glomeruli, vasculature, and tubulointerstitium. Aggressive immunosuppression likely contributed to one death in a patient with diabetes, and did not yield an overall or renal survival advantage in this cohort.