Mild Renal Artery Stenosis Can Induce Renovascular Hypertension and is Associated with Elevated Renal Vein Renin Secretion

Renovascular hypertension is a syndrome which encompasses the physiological response of the kidney to changes in renal blood flow and renal perfusion pressure. Such physiological changes can occur with renal artery occlusion irrespective of the severity of the lesion. We have analyzed hypertensive patients with mild renal artery stenosis and compared them to patients with no stenosis. Renal vein renin sampling from catheterization of the renal vein was performed in all these patients. Patients with mild stenosis had higher renal vein renin ratio (3.01 ± 1.5) than the patients with no stenosis (1.10 ± 0.29; p = 0.002). Patients with mild stenosis were also found to have higher diastolic blood pressure and renal artery resistive indices when compared to patients with no stenosis. We therefore conclude that mild stenosis can precipitate renin‐mediated hypertension in renovascular stenosis and also emphasis that parameters pertinent to renal physiology need to be evaluated before considering treatment options in patients with renal artery stenosis and medical management with RAAS blockade is the preferred modality of therapy for patients with renin‐mediated hypertension.     

Recurrent subependymoma of fourth ventricle with unusual atypical histological features: A case report

Subependymoma is a rare subtype of benign ependymal neoplasm with distinct histological features. Anaplastic transformation has not yet been reported in this tumor to date. We present here a very unusual case of a 62‐year‐old woman with recurrent subependymoma of the fourth ventricle with multiple atypical histological features. Histologically, the resected recurrent tumor showed characteristic small cell clusters and nests of ependymal cells with an interspersed gliofibrillary matrix as seen in a classic subependymoma. In addition, there were very unusual histological features, including multiple areas of necrosis, microvascular proliferation, thrombosed blood vessels, and scattered mitotic figures. No coexisting ependymoma component of higher World Health Organization (WHO) grade was present. Immunohistochemically, MIB‐1 labeling index was high, with up to 15% in the highest areas. Review of this patient's initial tumor, which was resected 6 years prior to recurrence, demonstrated features of a typical classic subependymoma without atypical features or a secondary tumor component. Subependymomas are known to be low‐grade tumors and are usually cured if completely excised. The tumor presented here is unique in that several atypical pathological features were found in an otherwise typical subependymoma. Our case may represent anaplastic transformation of subependymoma, although no such examples have been reported to date.     

Genomic and Functional Portrait of a Highly Virulent,CTX-M-15-Producing H30-Rx Subclone of Escherichia coli Sequence Type 131

Escherichia coli sequence type 131 (ST131) is a pandemic clone associated with multidrug-resistant, extraintestinal infections, attributable to the presence of the CTX-M-15 extended-spectrum β-lactamase gene and mutations entailing fluoroquinolone resistance. Studies on subclones within E. coli ST131 are critically required for targeting and implementation of successful control efforts. Our study comprehensively analyzed the genomic and functional attributes of the H30-Rx subclonal strains NA097 and NA114, belonging to the ST131 lineage. We carried out whole-genome sequencing, comparative analysis, phenotypic virulence assays, and profiling of the antibacterial responses of THP1 cells infected with these subclones. Phylogenomic analysis suggested that the strains were clonal in nature and confined entirely to a single clade. Comparative genomic analysis revealed that the virulence and resistance repertoires were comparable among the H30-Rx ST131 strains except for the commensal ST131 strain SE15. Similarly, seven phage-specific regions were found to be strongly associated with the H30-Rx strains but were largely absent in the genome of SE15. Phenotypic analysis confirmed the virulence and resistance similarities between the two strains. However, NA097 was found to be more robust than NA114 in terms of virulence gene carriage (dra operon), invasion ability (P < 0.05), and antimicrobial resistance (streptomycin resistance). RT² gene expression profiling revealed generic upregulation of key proinflammatory responses in THP1 cells, irrespective of ST131 lineage status. In conclusion, our study provides comprehensive, genome-inferred insights into the biology and immunological properties of ST131 strains and suggests clonal diversification of genomic and phenotypic features within the H30-Rx subclone of E. coli ST131.     

Fanconi-Bickel Syndrome - Mutation in SLC2A2 Gene

Fanconi-Bickel Syndrome (FBS) is a rare autosomal recessive disorder of carbohydrate metabolism. The defect in the GLUT 2 receptors in the hepatocytes, pancreas and renal tubules leads to symptoms secondary to glycogen storage, glucose metabolism and renal tubular dysfunction. Derangement in glucose metabolism is classical with fasting hypoglycemia and post-prandial hyperglycemia. The authors report a 4-year-old boy who presented with failure to thrive, motor delay, protuberant abdomen and was noted to have huge hepatomegaly with glycogen deposition in liver, and renal tubular acidosis. Gene sequencing revealed homozygous mutation, c.1330T > C in SLC2A2 gene, thus confirming the diagnosis of FBS. Only three mutations have been reported from India so far. The primary reason for referral to authors’ hospital was for liver transplantation, but an accurate diagnosis led to avoidance of the major surgery and streamlining of treatment with clinical benefit to the child and family.     

Plasma Exchange for Hemolytic Crisis and Acute Liver Failure in Wilson Disease

Wilson disease (WD) is a rare autosomal recessive disorder of copper metabolism which primarily involves the liver and the central nervous system. Rarely, WD can present as acute liver failure (ALF) and this disease is universally fatal in the absence of liver transplantation. The authors report a young girl with WD ALF, who showed signs of recovery after prompt initiation of plasma exchange (PE) and chelation therapy. Though liver transplantation could not be done in this child and the child died 8 d after stopping PE, this case highlights that PE can be a successful medical treatment in WD ALF and should be considered as a therapeutic measure to stabilize a patient by decreasing serum copper, reducing hemolysis, and helping to prevent renal tubular injury from copper and copper complexes until liver transplantation is possible.     

Multiple left ventricular thrombi in a patient with left ventricular noncompaction

The major clinical features of myocardial noncompaction are heart failure, arrhythmias, and thromboembolic events. Prominent myocardial trabeculae and deep recesses characteristic of myocardial noncompaction can cause stagnant blood flow and the formation of left ventricular clots. We describe the case of a 62-year-old woman who presented with symptoms of heart failure secondary to left ventricular noncompaction. Transthoracic and transesophageal echocardiography revealed multiple left ventricular thrombi, which had formed despite the patient's long-term therapy with aspirin.Anticoagulative therapy should be considered for patients with myocardial noncompaction who also have risk factors for thromboembolism, such as atrial fibrillation, a history of systemic embolism, or severe left ventricular systolic dysfunction. However, chronic antiplatelet therapy may not sufficiently prevent clot formation in patients who have myocardial noncompaction and severe left ventricular systolic dysfunction.     

Transthoracic Echocardiography of the HeartWare Left Ventricular Assist Device

BackgroundThe unique findings on transthoracic echocardiography of the HeartWare left ventricular assist device (LVAD) have not been previously described.Methods and ResultsHeartWare LVADs were implanted in 19 patients from May 2009 through December 2010; 152 comprehensive transthoracic echocardiograms (TTEs) performed postoperatively on these patients were retrospectively analyzed for device component visualization, inlet cannula/outflow conduit flow velocities, and imaging artifacts. The inlet cannula was adequately visualized in 66% of studies, incompletely visualized in 14%, and not visualized in 20%. Spectral Doppler interrogation of inlet cannula flow velocity was always uninterpretable due to artifact. Standard parasternal long-axis and apical views always included the inlet cannula in the imaging sector, resulting in a prominent “waterfall” color Doppler artifact obscuring the mitral valve. Inclusion of the inlet cannula in the imaging sector also precluded spectral Doppler interrogation of the mitral valve owing to artifact. The outflow conduit was partially visualized and interrogated by spectral Doppler in 68% of studies, and the average measured peak flow velocity was 1.4 m/s (range 1.0–1.9 m/s).ConclusionsThe HeartWare LVAD inlet cannula and outflow conduit are both readily visualized by TTE in a majority of patients. However, significant color and spectral Doppler artifacts occur when the inlet cannula is visualized in the imaging sector, necessitating routine off-axis Doppler interrogation of the mitral valve.