Treatment of hyperammonemia using in-line renal replacement and hyperosmolar therapies within an extracorporeal membrane oxygenation circuit.

After orthotopic lung transplantation, hyperammonemia can be a rare complication secondary to infection by organisms that produce urease or inhibit the urea cycle. This can cause neurotoxicity, cerebral edema, and seizures. Ammonia is unique in that it has a large volume of distribution. However, it is also readily dialyzable given its small molecular weight. As such, removal of ammonia requires renal replacement modalities that can both rapidly remove ammonia from the plasma space and allow for continuous removal to prevent rebound accumulation from intracellular stores. Prevention of iatrogenic osmotic lowering in this setting is required to prevent worsening of cerebral edema. Herein, we describe use of sequential in-line renal replacement therapy using both intermittent hemodialysis and continuous venovenous hemofiltration within an extracorporeal membrane oxygenation circuit in conjunction with higher sodium dialysate and 7.5% hypertonic saline to achieve these treatment goals.

A unique case of adamantinoma-like Ewing sarcoma in the calcaneus, exhibiting prominent squamous differentiation and displaying EWSR1 gene rearrangement.

Adamantinoma-like Ewing sarcoma is uncommonly reported in the skeletal sites, including small bones of the feet.A 15-year-old girl presented with pain and swelling in her left foot, leading to difficulty in walking for 8 months. Plain radiograph revealed an ill-defined, lytic-sclerotic lesion without significant periosteal reaction in her left calcaneus. Magnetic resonance imaging (MRI) revealed an expansile lesion involving the anterior calcaneus, which was hypointense on T1 and heterogeneously hyperintense on T2-weighted sequences, infiltrating the adjacent bones and soft tissues. On imaging, the differential diagnoses considered were a giant cell tumor and other primary bone tumors.Histopathological examination revealed a tumor composed of small round cells, with interspersed keratin pearls. Immunohistochemically, the tumor cells were positive for CD99/MIC2, pan-cytokeratin (AE1/AE3), p40, p63, NKX2.2, and synaptophysin. Diagnosis of adamantinoma-like Ewing sarcoma was offered on the initial biopsy. Furthermore, the tumor cells revealed EWSR1 gene rearrangement by fluorescence in situ hybridization, confirming this diagnosis. The patient underwent neoadjuvant chemotherapy, had a poor response, and finally underwent below-knee amputation.This constitutes a rare case of adamantinoma-like Ewing sarcoma in the calcaneus. Ewing sarcoma may be considered as a differential diagnosis for intraosseous lytic-sclerotic lesions, even without significant periosteal reaction, at unusual sites, such as the bones of the foot. Awareness of this entity and application of ancillary techniques is recommended for its exact diagnosis and in differentiating this rare variant from its diagnostic mimics. This case also indicates a poor chemotherapy response in this unusual variant of Ewing sarcoma, occurring in the calcaneus.

Perception towards Online Teaching-learning in Medical Education among Medical Students during COVID-19 Outbreak in Nepal: A Descriptive Cross-sectional Study.

INTRODUCTION: The outbreak of coronavirus disease in Nepal led medical colleges to suspend in person teaching-learning activities and ultimately online platform was introduced to deliver the contents of medical education. The objective of this study was to describe the perception of medical students towards online teaching-learning introduced during the COVID-19 outbreak in Nepal. METHODS: An online survey using a descriptive cross-sectional study design was carried out among 515 undergraduate medical students currently enrolled in medical colleges in Nepal. Ethical approval was sought from Nepal Health Research Council to conduct this study, and digital informed consent was taken from study respondents. A semi-structured questionnaire in Google form was utilized to collect data. The link of the Google form was sent to the potential respondents through email and social media. Descriptive statistics, including frequency, percentage, mean, and standard deviation were used to analyze data in Stastical Package for the Social Sciences version 20. Ethical approval was sought from Nepal Health Research Council to conduct this study, and digital informed consent was taken from study respondants. RESULTS: The overall score of perception of online teaching-learning was 17.61±7.19, which indicated many problems in this method of teaching-learning. The mean score of perception of online teaching-learning was found to be different across sex, location of enrolled medical colleges, having a personal electronic device, having an internet connection at residence, having separate room/space for attending online classes, and self-rated computer skills. Moreover, only 28 (5.4%) of respondents had perceived online teaching-learning as a better method of delivering content of medical curricula. CONCLUSIONS: Surveyed medical students in Nepal were found to perceive many problems in online teaching-learning. Moreover, management and faculty members need to take the necessary measures for enhancing the online teaching-learning quality.

High-efficiency, high-flux in-line hemofiltration using a high blood flow extracorporeal circuit.

The ability of current renal replacement therapy modalities to achieve rapid solute removal is limited by membrane surface area and blood flow rate. Extracorporeal membrane oxygenation offers high blood flow and hemodynamic support that may be harnessed to overcome limitations in traditional renal replacement therapy. Using an extracorporeal membrane oxygenation circuit, we describe a high blood flow, high-efficiency hemofiltration technique using in-line hemofilters (hemoconcentrators) and standard replacement fluid to enhance solute clearance. Using this approach and a total of 5 L of replacement volume per treatment, creatinine (Cr) clearances of 8.3 L/hour and 11.2 L/hour using one and two hemoconcentrators, respectively, were achieved. With use of a high blood flow rate of up to 5 L/min, this hemofiltration technique can potentially offer clearance of 30 times that of continuous renal replacement therapy and of 6 times that of hemodialysis which may expand the ability to remove substances traditionally not considered removable via existing extracorporeal therapies.

Plant-based diets for prevention and management of chronic kidney disease.

PURPOSE OF REVIEW: Plant-based diets have been used with growing popularity for the treatment of a wide range of lifestyle-related diseases, including diabetes, hypertension, and obesity. With the reinvigoration of the dietary management of chronic kidney disease (CKD) and the use of low protein diets for secondary prevention of CKD to delay or prevent dialysis therapy, there is an increasing interest in the potential role of plant-based diets for these patients. RECENT FINDINGS: Recently, a body of evidence related to the role of plant-based diets in preventing CKD has reemerged. Several observational studies have shown that red and processed meat have been associated with increased risk of CKD as well as faster progression in those with preexisting CKD. In several substitution analyses, replacement of one serving of red and/or processed meat has been linked with sizable reductions in CKD risk. Although limited, experimental trials for the treatment of metabolic acidosis in CKD with fruits and vegetables show outcomes comparable to oral bicarbonate. The use of plant-based diets in CKD may have other benefits in the areas of hypertension, weight, hyperphosphatemia, reductions in hyperfiltration, and, possibly, mortality. The risk of potassium overload from plant-based diets appears overstated, mostly opinion-based, and not supported by the evidence. Plant-based diets are generally well tolerated and provide adequate protein intake, including essential amino acids as long as the diet is correctly implemented. SUMMARY: Plant-based diets should be recommended for both primary and secondary prevention of CKD. Concerns of hyperkalemia and protein inadequacy related to plant-based diets may be outdated and unsupported by the current body of literature. Healthcare providers in general medicine and nephrology can consider plant-based diets as an important tool for prevention and management of CKD.

Metastatic prostate cancer presenting as tumour-induced osteomalacia.

Tumour-induced osteomalacia (TIO), or oncogenic osteomalacia, is a paraneoplastic syndrome marked by hypophosphataemia, renal phosphate wasting, bone pain, weakness, and fractures. The syndrome has been reported with both benign and malignant tumours including parotid gland basal cell tumours, thyroid carcinomas, colon adenocarcinomas, and prostate cancer. Often, the syndrome is marked by an insidious course during which patients present with generalised bony pain and weakness, which do not resolve until the underlying tumour is identified and treated. We present a case of a patient with Parkinson's disease whose subacute weakness, lower extremity paresis, and renal phosphate wasting led to the synchronous diagnosis of metastatic prostate adenocarcinoma and TIO.

Adequacy of Plant-Based Proteins in Chronic Kidney Disease.

Concerns regarding protein and amino acid deficiencies with plant-based proteins have precluded their use in chronic kidney disease (CKD) patients. Many of these concerns were debunked years ago, but recommendations persist regarding the use of "high-biological value" (animal-based) proteins in CKD patients, which may contribute to worsening of other parameters such as blood pressure, metabolic acidosis, and hyperphosphatemia. Plant-based proteins are sufficient in meeting both quantity and quality requirements. Those eating primarily plant-based diets have been observed to consume approximately 1.0 g/kg/day of protein, or more. CKD patients have been seen to consume 0.7-0.9 g/kg/day of mostly plant-based protein without any negative effects. Furthermore, those substituting animal-based proteins for plant-based proteins have shown reductions in severity of hypertension, hyperphosphatemia, and metabolic acidosis. Plant-based proteins, when consumed in a varied diet, are not only nutritionally adequate but have pleiotropic effects which may favor their use in CKD patients.

Using Electrolyte Free Water Balance to Rationalize and Treat Dysnatremias.

Dysnatremias or abnormalities in plasma [Na+] are often termed disorders of water balance, an unclear physiologic concept often confused with changes in total fluid balance. However, most clinicians clearly recognize that hypertonic or hypotonic gains or losses alter plasma [Na+], while isotonic changes do not modify plasma [Na+]. This concept can be conceptualized as the electrolyte free water balance (EFWB), which defines the non-isotonic components of inputs and outputs to determine their effect on plasma [Na+]. EFWB is mathematically proportional to the rate of change in plasma [Na+] (dPNa/dt) and, therefore, is actively regulated to zero so that plasma [Na+] remains stable at its homeostatic set point. Dysnatremias are, therefore, disorders of EFWB and the relationship between EFWB and dPNa/dt provides a rationale for therapeutic strategies incorporating mass and volume balance. Herein, we leverage dPNa/dt as a desired rate of correction of plasma [Na+] to define a stepwise approach for the treatment of dysnatremias.

A factor analytical study report on mania from Nepal.

BACKGROUND AND OBJECTIVES: Phenomenological studies on mood disorder are rare in Nepal which prompted us to undertake the current factor analytical study of mania. MATERIALS AND METHODS: It was a cross-sectional descriptive study for which we did purposive sampling technique according to certain inclusion and exclusion criteria. The study sample consists of fifty patients, who fulfilled the International Classification of Diseases, Tenth Edition (ICD-10) diagnostic criteria for Manic Episode and/or Bipolar Affective Disorder-current episode mania. Tools used were ICD-10 Diagnostic Criteria for Research, Young's Mania Rating Scale (YMRS), and Brief Psychiatric Rating Scale (BPRS). Principal component factor analysis was applied to the 35 symptoms taken from YMRS and BPRS. RESULTS: Factor analysis revealed the presence of four main factors, which explained 51.082% of the total variance. These are "pure mania" which isolated 11 manic symptoms, "dysphoric mania" which isolated five depressive symptoms, "hostile mania" which isolated six symptoms, and the fourth factor, we called it "delirious mania," isolated four symptoms. CONCLUSION: The identified factors and subtypes are a useful conceptualization of atypical features among patients with acute mania. Further validation studies are required to determine whether the identified subtypes are of clinical and theoretical importance.

Emotional prosody and diffusion tensor imaging in children after traumatic brain injury.

PRIMARY OBJECTIVE: Brain structures and their white matter connections that may contribute to emotion processing and may be vulnerable to disruption by a traumatic brain injury (TBI) occurring in childhood have not been thoroughly explored. RESEARCH DESIGN AND METHODS: The current investigation examines the relationship between diffusion tensor imaging (DTI) metrics, including fractional anisotropy (FA) and apparent diffusion coefficient (ADC), and 3-month post-injury performance on a task of emotion prosody recognition and a control task of phonological discrimination in a group of 91 children who sustained either a moderate-to-severe TBI (n = 45) or orthopaedic injury (OI) (n = 46). MAIN OUTCOMES AND RESULTS: Brain-behaviour findings within OI participants confirmed relationships between several significant white matter tracts in emotional prosody performance (i.e. the cingulum bundle, genu of the corpus callosum, inferior longitudinal fasciculus (ILF) and the inferior fronto-occipital fasciculus (IFOF). The cingulum and genu were also related to phonological discrimination performance. The TBI group demonstrated few strong brain behaviour relationships, with significant findings emerging only in the cingulum bundle for Emotional Prosody and the genu for Phonological Processing. CONCLUSION: The lack of clear relationships in the TBI group is discussed in terms of the likely disruption to cortical networks secondary to significant brain injuries.

Blastic plasmacytoid dendritic cell neoplasm presenting as fever with diffuse cutaneous nodules.

A young man, presented with high-grade fever and disseminated asymptomatic skin lesions of 6-weeks duration. Cutaneous examination revealed multiple infiltrated monomorphic skin-colored papules and nodules upto 2×2 cm all over scalp, face, trunk and extremities. Light microscopy of nodules showed diffuse infiltration of dermis and subcutis by a tumor composed of medium to large cells with round to ovoid nuclei with fine chromatin, few with visible nucleoli and scanty to moderate amounts of eosinophilic cytoplasm. Tumor cells were positive for CD4, CD8, CD56 and negative for CD30, terminal deoxynucleotidyl transferase and Alk-1. Excised axillary lymph node showed similar morphologic and immunohistochemical findings. There was bone marrow involvement with infiltrate of large atypical/immature lymphoid cells. Diagnosis of blastic plasmacytoid dendritic cell neoplasm was made. This is a rare neoplasm. presenting commonly in the skin, with or without concurrent extracutaneous disease.

Diffusion tensor imaging and volumetric analysis of the ventral striatum in adults with traumatic brain injury.

OBJECTIVES: The aim was to determine if there are changes in the integrity and volume of the ventral striatum following severe traumatic brain injury (TBI) and if these changes relate to executive functioning. METHODS: This study recruited 14 participants with severe TBI (mean age: 22 years) and 15 demographically-matched controls. All participants underwent magnetic resonance imaging with diffusion tensor imaging (DTI) and volumetric analysis at 6 months post-injury. Participants with TBI underwent neuropsychological testing and the relation between imaging data and cognitive performance was examined. RESULTS: Differences in DTI parameters (fractional anisotropy (FA) and apparent diffusion coefficient (ADC)) were found between participants with TBI and controls. Correlations between right and left ventral striatum ADC and the executive functioning factor of the Neurobehavioural Rating Scale-Revised (NRS-R) were found. Correlations between right ventral striatum FA and the Controlled Oral Word Association Test, Trails Making Test Part B (TMT-B) time and NRS-R executive functioning factor were also found. Volumetric analysis showed a difference only in left nucleus accumbens between TBI and control groups. CONCLUSIONS: The integrity of the ventral striatum is affected following severe TBI. Decreases in executive functioning are related to damage to the ventral striatum and its associated structures.

Hemodynamic characteristics and predictors of pulmonary hypertension in patients with sickle cell disease.

Pulmonary hypertension is a common co-morbidity of sickle cell disease with an associated increased mortality risk, but its etiology is not well-understood. To evaluate the hemodynamic characteristics, clinical predictors, and cardiovascular manifestations of elevated pulmonary arterial pressure in this population, we performed noninvasive hemodynamic assessments of 135 patients with sickle cell disease using Doppler echocardiography. A diagnosis of pulmonary hypertension was determined by gender-, age-, and body mass index-specific normal reference ranges for tricuspid regurgitation jet velocities (TRVs). A high TRV was noted in 34 patients (25%). Pulmonary vascular resistance was elevated in only 2 (6%) of the 34 patients with suspected pulmonary hypertension but was significantly greater than in those with normal TRV. On univariate regression, the TRV correlated with age, body mass index, left atrial pressure, and right ventricular stroke volume and was negatively associated with hemoglobin and glomerular filtration rate. The left atrial pressure, right ventricular stroke volume, and hemoglobin remained independent predictors of TRV in a multivariate model. A greater TRV was also associated with larger right ventricular and right atrial chamber sizes and greater N-terminal probrain natriuretic peptide levels. In conclusion, our results suggest that the mild elevation in TRV often observed in patients with sickle cell disease is rarely associated with a high pulmonary vascular resistance and that multiple factors-including the compensatory high output state associated with anemia, pulmonary venous hypertension, and pulmonary vasculopathy-can contribute to an elevated pulmonary arterial pressure in these patients.

The temporal stem in traumatic brain injury: preliminary findings.

The temporal stem (TS) of the temporal lobe is a major white matter (WM) region containing several major pathways that connect the temporal lobe with the rest of the brain. Because of its location, it may be particularly vulnerable to shear-strain effects resulting from traumatic brain injury (TBI). A case vignette is presented in a patient with severe brain injury and focal TS pathology. Also, 12 severe TBI subjects unselected for TS pathology were compared to demographically matched, neurologically-intact controls using diffusion tensor imaging (DTI) to examine white matter tracts associated with the TS, including the inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF), arcuate fasciculus (AF), cingulum bundle (CB) and the uncinate fasciculus (UF). For each tract, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were computed and compared between the two groups and also examined in relationship to memory performance in the TBI subjects. Significant FA and ADC differences were observed in all tracts in the TBI patients compared to controls, with several relationships with memory outcome noted in the IFOF, ILF and AF. Based on these preliminary findings, the potential role of TBI-induced WM disconnection involving the TS is discussed as well as the relationship of TS damage to neurobehavioral outcome. The need for future studies specifically examining the role of TS injury in TBI is emphasized.