We have posted updates of the following topics:CNS & pituitary tumors > Gliomas, glioneuronal tumors, and neuronal tumors > Neuronal and mixed neuronal-glial tumors > Dysembryoplastic neuroepithelial tumor
by Chris Dampier, M.D., P.J. Cimino, M.D., Ph.D.
Topic summary: Cortex based glioneuronal neoplasm that is often located in the mesial temporal lobe of adolescents and young adults and associated with medically refractory epilepsy, usually with activating mutations of FGFR1, CNS WHO grade 1. M:F = 1.2:1; 5.9% of epilepsy surgery cases. Most common sites: temporal lobe, especially medial (67%), frontal lobe (16%), other cortex (16.%). Presents clinically with intractable seizures; radiographically is sharply demarcated, nodular, cortical lesion(s) without edema or enhancement. Treatment: surgical resection; radiation or chemotherapy is generally not applicable. Benign lesion with low rate of recurrence after resection; rare case reports of malignant transformation.
CNS nontumor > Toxic and metabolic disorders > Wernicke-Korsakoff syndrome
by Palgun Nisarga, M.D., Kymberly A. Gyure, M.D.
Topic summary: Acute and chronic neuropsychiatric condition secondary to thiamine (vitamin B1) deficiency. Wernicke encephalopathy (WE): short lived and severe condition. Korsakoff syndrome (KS): a disproportionate impairment in memory relative to other features of cognition that is chronic, long lasting and debilitating; usually follows or accompanies Wernicke encephalopathy. Inability to utilize glucose due to deficiency of thiamine, a cofactor for 3 enzymatic processes. < 1 – 3% in autopsies of the general population; increases in cases of alcohol abuse and alcohol related death (12.5% and 29 – 59%, respectively). ~20% mortality rate (without treatment); ~80% of individuals who survive Wernicke encephalopathy will develop Korsakoff syndrome (without treatment). Treatment: parenteral thiamine administration, given before or with intravenous glucose.
Heart > Systemic conditions > Sarcoidosis
by Matthew G.K. Charles, B.A., Carolyn Glass, M.D., Ph.D.
Topic summary: Cardiac sarcoidosis is a type of infiltrative cardiomyopathy and a potential cause of heart failure. Nonnecrotizing granulomata are classic; presents with symptoms of cardiac dysfunction (arrhythmias, conduction disturbances). Electrocardiogram (ECG): PR lengthening, T wave abnormalities, Q waves; echocardiograms: decreased left ventricular ejection fraction, ventricular aneurysm, regional wall motion abnormality, basal septal thinning. Prognosis is poor if complicated by heart failure; in the U.S., 13 – 25% of deaths from sarcoidosis have been attributed to cardiac sarcoidosis; 5 year estimate of event free survival is 70 – 80%. Management largely involves treatment of underlying cardiac dysfunction and prevention of cardiovascular disease.
Informatics, digital & computational pathology > Fluorescence microscopy > Virtual staining
by Joshua Levy, Ph.D., Louis Vaickus, M.D., Ph.D.
Topic summary: Virtual staining (VS) is the conversion of an H&E (or other common standard stain, e.g., PAS) digital whole slide image (WSI) to a digital prediction of a special stain (e.g., trichrome, CK AE1 / AE3 IHC); the prediction relies on the detection of morphological features (if they exist) of the source WSI, which inform the distribution of a special stain. Virtual staining technologies leverage artificial neural networks (ANN) to generate synthetic images of tissue slides with predictions of the results of special staining reagents (chemical and IHC). Advantage: ameliorates laboratory infrastructure burdens through quick access to reflexive tissue staining at virtually no cost. Disadvantage: generative adversarial networks (GAN) may hallucinate histological features that look real but are incorrectly placed or should not be present.
Placenta > Nonneoplastic placental conditions and abnormalities > Placental findings in specific conditions > Toxemia of pregnancy (preeclampsia and eclampsia)
by Khaldoon Aljerian, M.D., M.H.Sc.
Topic summary: Preeclampsia is a pregnancy specific hypertensive disorder diagnosed by the presence of 3 main signs: hypertension, proteinuria and edema. Thrombocytopenia, recalcitrant epigastric pain, progressive renal dysfunction, pulmonary edema; some cerebral and ophthalmic manifestations could be evident. Prevalent within young pregnant women with a tendency to develop hypertension. Eclampsia: preeclampsia + convulsions; ~40% of women with eclampsia do not demonstrate conspicuous preceding symptoms before convulsions start. Treatment: delivery of baby and placenta (most effective); corticosteroids (promote lung maturation of baby); antihypertensives (treat hypertension); anticonvulsants (magnesium sulfate, treat convulsions).